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Volume 61, Number 18, Page 2543


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Part III

Department of Labor

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Mine Safety and Health Administration
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30 CFR Part 75

Safety Standards for Underground Coal Mine Ventilation; Final Rule

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Department of Labor

Mine Safety and Health Administration

30 CFR Part 75

RIN 1219-AA11


Safety Standards for Underground Coal Mine Ventilation

AGENCY: Mine Safety and Health Administration, (MSHA) Labor.

ACTION: Final rule.

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SUMMARY: This final rule revises the Mine Safety and Health 
Administration's (MSHA's) existing safety standards for ventilation of 
underground coal mines. After publication of the existing standards, 
the U.S. Court of Appeals in the D.C. Circuit stayed the application of 
one standard and MSHA stayed two standards. The rule revises these 
stayed provisions, revises or clarifies other provisions in the rule 
and includes some new provisions. The provisions of the final rule are 
expected to decrease the potential for fatalities, particularly 
accidents which can result in multiple deaths, and to reduce the risk 
of injuries and illnesses in underground coal mines. For the 
convenience of the reader, MSHA has published the full text of the 
ventilation standards for underground coal mines in this document.

EFFECTIVE DATE: The final rule is effective June 10, 1996.

FOR FURTHER INFORMATION CONTACT: Patricia W. Silvey, Director, Office 
of Standards, Regulations and Variances, MSHA, phone 703/ 235-1910; fax 
703/235-5551.

SUPPLEMENTARY INFORMATION:

I. Background

    The mining of coal underground has historically been recognized as 
one of the more hazardous occupations in the world. It is a universally 
recognized principle of underground coal mine safety that there must be 
proper ventilation of the mine. Indeed, no aspect of safety in 
underground coal mining is more fundamental than proper ventilation. A 
basic tenet of mining safety states that ventilation must be 
sufficient: (1) To dilute, render harmless and carry away the hazardous 
components of mine air, such as potentially explosive methane; and (2) 
to provide necessary levels of oxygen to the miners' working 
environment. Ventilation safety programs are designed around this 
philosophy. The history of mining is replete with tragic incidents 
where one aspect or another of a necessary ventilation safety 
protection was either not in place or not followed, with disastrous 
results. Examples include the explosion at the Monogah mine in 1907 in 
which 362 miners perished, the worst mining disaster in the history of 
the United States. Other more recent examples include the Farmington 
disaster in 1968 in which 78 miners died, the Scotia mine in 1976 where 
26 died, Grundy No. 17 in 1981 where 13 died, Wilberg in 1984 where 27 
died, Pyro in 1989 with 10 deaths and Southmountain in 1992 where 8 
miners died. In 1969 and again in 1977, Congress recognized the hazards 
of improper ventilation and established a role for the government in 
addressing ventilation hazards. MSHA, with the cooperation of labor and 
industry, has met with a large measure of success in reducing the 
accidents, injuries and fatalities that have resulted from poor 
ventilation practices. For example, explosions and fires in a 29 year 
period from 1940 to 1968 resulted in the deaths of 491 miners. Since 
the passage of the Federal Coal Mine Health and Safety Act of 1969, 178 
explosion and fire related deaths have occurred. While MSHA recognizes 
that this number is still unacceptable, the significant reduction in 
loss of life cannot be ignored. To a great extent, the framework for 
this success has been the implementation of effective ventilation 
standards.
    Preventing recurrence of disasters like those of the past remains 
the top priority of MSHA. MSHA believes that a serious commitment by 
management, labor, and government is necessary to develop effective, 
yet reasonable and practical regulations that protect the safety and 
health of our nation's miners. MSHA anticipates that this rulemaking, 
which revises portions of the comprehensive ventilation rule published 
in 1992 (57 FR 20868, May 15, 1992) and adds new provisions, will bring 
the coal mining industry closer to that objective.
    The comprehensive 1992 ventilation rulemaking was closely followed 
by interested industry and labor groups, who frequently expressed 
divergent views on approaches to resolving ventilation issues. Certain 
commenters exercised their right to challenge the rule and the U.S. 
Court of Appeals for the D.C. Circuit Court stayed one provision 
relating to oxygen and carbon dioxide in the bleeder entries. MSHA held 
a series of informational meetings around the country during which it 
explained the application of the rule. In so doing, MSHA listened to 
many questions about the implementation of the rule. MSHA was sensitive 
to the views expressed at these meetings and gave serious consideration 
to these issues. Some of these comments became the basis for portions 
of this rulemaking. Internal discussions of MSHA's experience with the 
implementation of the rule led MSHA to include still other issues in 
this rulemaking. In fact, MSHA stayed the application of two additional 
provisions in response to potential problems pointed out by interested 
parties. These stayed provisions relate to actions following the 
stoppage of the main mine fan with persons underground and to a 
potential fire hazard from the enclosure of compressors in a 
noncombustible structure. MSHA addresses these issues in the 
rulemaking. Once MSHA decided that it was going to proceed with a 
rulemaking to address these issues, it added other provisions to the 
package to allow all parties an opportunity to comment where they 
expressed the view that they had insufficient opportunity to comment on 
the existing rule (The comprehensive rule that was published in the 
Federal Register on May 15, 1992). The rule MSHA proposed also included 
issues raised by parties in litigation challenging the existing rule. 
MSHA anticipates that the final rule should resolve matters included in 
the challenge raised by the litigation of the existing rule. Finally, 
in an effort to address confusion that seemed to exist with certain 
provisions of the existing ventilation rule promulgated in May of 1992, 
MSHA either proposed clarifications to the existing rule or discussed 
the affected provisions in the preambles to the proposed and final 
rules in an effort to clarify them.
    The issues in the rulemaking are complex and highly technical. 
Comments to the proposal (published on May 19, 1994, 59 FR 26536) and 
comments following the public hearings (held in September and October 
1994, in Price, Utah, Logan, West Virginia, and Washington, 
Pennsylvania) were extensive. One party alone submitted over two 
thousand pages of written comments and over 275 exhibits. Not only were 
the safety issues involved complex, but in many cases, MSHA's task was 
made more difficult by hearing diametrically opposed viewpoints.

A. General Discussion

    In developing the final rule, MSHA has made every effort to address 
the comments received during the rulemaking, and to develop practical 
requirements for real safety problems. Both the costs and the benefits 
of each standard were also considered. In addition, each standard, as 
well as revisions and deletions, was carefully considered against the 
statutory requirement that nothing in the final rule shall reduce the 
protection afforded miners by an existing mandatory health or safety 
standard. Where appropriate, MSHA has provided for a phase in period to 
allow mine operators time to effectively plan and implement the 
necessary changes.
    MSHA carefully analyzed the comments received and responded in many 
instances by revising the proposed requirements. For example, unlike 
the proposal, the final rule does not require the second level 
countersigning of records; allows the use of nonpermissible equipment 
when conducting an examination upon restart of a fan following 
unintentional fan stoppages, and requires pressure recording devices or 
an option of the use of a fan monitoring system to be used on all main 
mine fans.
    Several commenters strongly urged MSHA to proceed in this 
rulemaking on the issue of using air coursed through the belt entries 
(``belt air'') to ventilate the working face. MSHA has completed its 
consideration of the Report of the Secretary's Advisory Committee 
Report on Belt Air and has placed the issue of using belt air to 
ventilate the working face on the rulemaking agenda for development of 
a proposed rule. Thus, ``belt air'' is not addressed in this 
rulemaking.
    MSHA has also received comments and recommendations on a number of 
other issues that are outside the scope of this rulemaking. For 
example, much of the extensive testimony directed toward the use of 
atmospheric monitoring systems was beyond the issues dealt with in this 
rulemaking. Also, recommendations for the use of transparent or 
translucent material for check curtains exceed the scope of this 
rulemaking. The final rule, therefore, does not include these 
recommendations.
    Commenters to the proposal frequently included a discussion of 
various accident reports, most written by MSHA. In addition, there were 
discussions of other documents related to specific incidents or mines, 
such as MSHA Internal Review Reports or specific mine plans. In some 
cases, the documents were submitted for inclusion in the record. In 
other cases, the documents were merely referenced.
    MSHA is independently aware of the extensive history of ventilation 
related explosions, and has considered this information. Where 
appropriate, this information is discussed in the section-by-section 
analysis in the preamble of this rule. MSHA is aware that accidents can 
result from or be contributed to by the violation of one or more of the 
existing standards. In that context, MSHA has found that the solution 
is not necessarily to promulgate another standard. (The offender may be 
as likely to ignore it as well.) Instead, for demonstrated 
noncompliance with existing standards, the solution is often found in 
increased emphasis, training, or enforcement, rather than in the 
promulgation of additional rules.
    Several sections of the final rule deal with requirements for 
sections and areas where mechanized mining equipment is being installed 
or removed. These provisions, which were included in the existing 
standard published in May 1992, were reproposed without change for the 
purpose of receiving additional comments from all interested parties. 
One commenter cited the William Station mine explosion as evidence of 
the need for these requirements. Other commenters reiterated an earlier 
objection that the standards were procedurally flawed. MSHA does not 
agree that these provisions are procedurally flawed and notes that each 
of these standards was reproposed and not simply restated as part of 
this rulemaking. Comments relative to the 

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technical merits of an individual standard are addressed in the 
section-by-section portion of this preamble.

Recordkeeping Requirements in the Final Rule

    The final rule revises the recordkeeping requirements for several 
standards. The standards affected are Sec. 75.310, Installation of main 
mine fans; Sec. 75.312, Main mine fan examinations and records; 
Sec. 75.342, Methane monitors; Sec. 75.360, Preshift examination; 
Sec. 75.362, On-shift examination; Sec. 75.363, Hazardous conditions; 
posting, correcting and recording; Sec. 75.364, Weekly examinations; 
and Sec. 75.370, Mine ventilation plan; contents.
    Generally, the final rule requires examiners to record the results 
of methane tests as a percent of methane detected; records must be made 
in a book that is secure and not susceptible to alteration, or 
electronically in such a manner as to be secure and not susceptible to 
alteration; and records must be countersigned by the mine foreman by 
the end of the mine foreman's next regularly scheduled working shift. 
These rules are intended to assure that examination results are 
maintained and made available, and that the appropriate level of mine 
management is made aware of conditions or problems requiring attention. 
The revisions also help assure the integrity of records and enable mine 
management to review the quality of the examinations. MSHA intends the 
term ``secure and not susceptible to alteration'' when applied to 
electronic storage to mean that the stored record cannot be modified. 
One example of acceptable storage would be a ``write once, read many'' 
drive.
    Numerous comments were received both supporting and opposing the 
proposed recordkeeping requirements. MSHA reviewed and fully considered 
each of these comments. The proposal would have required that records 
be kept in either state-approved books or in bound books with 
sequential machine-numbered pages. Commenters argued that under the 
existing rule records may be falsified or altered. Commenters also 
stated that accident investigations have demonstrated the need for 
improved records. Other commenters asserted that the proposed 
requirement for bound books with sequential machine-numbered pages adds 
an economic burden for the majority of compliant operators and another 
way should be found, ``to foil the very few who are recalcitrant.'' 
Other commenters stated that since all records currently include dates 
and times, machine-numbered pages are unnecessary.
    Some record books that are currently in use and acceptable under 
the existing standards are vulnerable to misuse or manipulation. For 
example, under the existing rule, records could be kept in a spiral 
notebook or even a loose leaf binder. The final rule addresses this 
issue by requiring that records be made in books that are secure and 
not susceptible to alteration. Examples of books that are considered by 
MSHA to be secure and not susceptible to alteration include, but are 
not limited to, record books that are currently approved by state mine 
safety agencies, and permanently bound books. Examples of books that 
would not be considered books that are secure and not susceptible to 
alteration include loose leaf binders and spiral note books.
    Several commenters advocated the use of computers for the storage 
and retrieval of records. In support of this approach, the commenters 
cited computer records as being highly accurate, requiring less storage 
space and facilitating data retrieval. Other commenters expressed 
concern for the security of records stored electronically, and offered 
examples of breaches of security in record systems at banks and 
national security installations as evidence to support this concern.
    Electronic storage of information and assessing it through 
computers is more and more a common business practice generally and in 
the mining industry. Recognizing this trend, the final rule permits the 
use of electronically stored records provided they are secure and not 
susceptible to alteration, are able to capture the information and 
signatures required, and are accessible to the representative of the 
miners and the representatives of the Secretary. Based on the 
rulemaking record, MSHA believes that electronic records meeting these 
criteria are practical and as reliable as traditional records.
    In the preamble to the proposal, MSHA expressed its intent to 
require a hard copy printout of the information stored electronically 
to be available within 1 hour of a request, and to require backing up 
of the information within 24 hours. Commenters objected to making the 
records available within 1 hour as being too stringent and 
unnecessarily requiring a person to be on duty at all times. MSHA 
agrees that the requirement would be overly burdensome and has not 
included it in the final rule. Similarly, MSHA has not included a 
specific requirement for backing up the computer data. The final rule 
requires that the records be secure. This encompasses backing up the 
data as appropriate to the conditions and electronic storage system 
used at the mine. Upon reconsideration, MSHA has concluded that an 
additional specific requirement would be an unnecessary burden and has 
not included it in the rule.
    A variety of comments were received regarding the countersigning of 
certain records by the mine foreman, and the time frame permitted for 
countersigning. The final rule adopts the proposal that the mine 
foreman must countersign the record by the end of the mine foreman's 
next regularly scheduled working shift. The mine foreman is the person 
most responsible for the day-to-day operation of the mine. It is 
essential for the health and safety of the miners that the mine foreman 
be fully aware of the information contained in examination reports so 
as to be able to allocate resources to correct safety problems as they 
develop. Allowing until the end of the mine foreman's next regularly 
scheduled working shift to countersign the reports assures that the 
mine foreman is aware of the results of the examination in sufficient 
time to initiate corrective actions. In response to commenters, the 
final rule allows a mine official equivalent to a mine foreman to 
countersign the records.
    Some commenters suggested that the time for countersigning is 
unnecessarily long, and that the final rule should restore a previous 
requirement that countersigning be completed ``promptly.'' The term 
``promptly'' involves a level of ambiguity that is eliminated by 
specifying the time for countersigning records. The record does not 
show that the time set by the final rule would expose miners to safety 
or health risks. Also, hazardous conditions are required to be 
corrected immediately.
    Commenters suggested that the term ``mine foreman'' be replaced by 
a ``certified person responsible for ventilation of the mine or his 
designee.'' Another commenter suggested that the record could be 
countersigned by the mine foreman or any other mine official 
responsible for the day-to-day operation of the mine. Commenters stated 
that some operations no longer use the terms ``mine foreman'', ``mine 
manager,'' or ``superintendent.'' To provide for alternative management 
titles, the final rule incorporates the phrase ``or equivalent mine 
official.''
    Numerous comments were received regarding the requirement of the 
proposal for second level countersigning by the mine superintendent, 
mine manager, or other mine official to whom the mine foreman is 
directly accountable within 2 scheduled 

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production days thereafter. Commenters objecting to the proposal stated 
that higher level management should be able to delegate responsibility, 
noting that often this level of official has more than one mine to 
oversee and may not necessarily be available within the proposed two 
days. One commenter suggested allowing three days for second level 
countersigning in order to recognize that such an official often has 
numerous obligations and to allow for normal absences. Other commenters 
simply recommended that the second level countersigning be deleted.
    Another commenter stated that some states hold the mine foreman 
legally responsible, that the mine foreman should correct hazardous 
conditions immediately and withdraw miners as appropriate, and that the 
second level countersigning would add no measure of safety. One 
commenter noted that in many cases the mine manager or superintendent 
is not a certified individual and long periods may elapse during which 
this person does not go underground. In these instances, the person 
countersigning would have little or no understanding or first hand 
knowledge of the conditions in the mine. Commenters stated that 
countersigning by the mine foreman is adequate notification to the 
operator of any deficiency and that the mine foreman has the necessary 
resources and responsibility to correct any situation noted in the 
records.
    Other commenters supported the proposal noting that second level 
countersigning would provide an additional level of accountability. 
These commenters also suggested that in the event of a major accident, 
the second level countersigning requirement would be important in fully 
assessing the contributing causes.
    MSHA has determined that countersigning by the mine foreman or 
equivalent mine official, as specified in the final rule, provides the 
means necessary to detect and correct developing hazards in a mine. 
Countersigning by the mine foreman assures the necessary notification 
to an official with the knowledge of the day-to-day operation of the 
mine having the authority to maintain the mine in a safe operating 
condition. Agency experience has demonstrated that higher level mine 
officials commonly lack hands-on involvement or in-depth knowledge of 
the specific conditions underground or how the highly detailed 
ventilation rules impact upon those conditions. Therefore, 
countersigning by a mine official at a higher level does not assure any 
additional level of safety and imposes an unnecessary burden.

B. Section-by-Section Discussion

    The following section-by-section portion of the preamble discusses 
each provision affected. The text of the final rule is included at the 
end of the document.

Section 75.301 Definitions

    The final rule revises the definition of return air to permit 
operators to designate certain air courses as return air courses for 
the purpose of ventilating structures, areas or installations that are 
required to be ventilated to return air courses and for ventilating 
seals when the air in the air course will not be used to ventilate 
working places. Thus, an operator wishing to split air off of an intake 
for the purpose of ventilating shops, electrical installations, or for 
other purposes, could designate the air course into which the split is 
directed as a return provided the air in the air course would not be 
used to ventilate working places or other locations, structures, 
installations or areas required to be ventilated with intake air. 
Commenters generally agreed with the change. However, one commenter 
expressed the concern that air currents ventilating electrical 
installations could be coursed to the conveyor belt entry before being 
coursed to a redesignated return air course, and thus not vented 
directly to a return. The commenter expressed the opinion that because 
the air is not vented directly to a return under this scenario, the 
rule would not permit this practice. MSHA does not agree with the 
commenter's interpretation and the final rule, consistent with 
Sec. 75.340, permits this practice.
    MSHA does not anticipate that operators will need to redesignate 
air courses on a routine basis. When questions arise as to the need to 
redesignate an intake as a return, the operator should contact the 
local MSHA office. In order that all interested persons are made aware 
when an air course is redesignated, the final rule requires in 
Sec. 75.372, Mine ventilation map, that such redesignated air courses 
be shown on the mine's ventilation map.

Section 75.310 Installation of Main Mine Fans

    The main mine fans serve a vital role in providing ventilation to 
prevent methane accumulations and possible explosions as well as 
providing miners with a healthful working environment. Section 75.310 
is primarily directed at protecting the main mine fans from fires and 
damage in the event of an underground explosion so that necessary 
ventilation can be maintained. Monitoring of the fans to assure that 
they are operating properly is an element of this protection. The final 
rule for Sec. 75.310 revises paragraphs (a) and (c) of the existing 
rule. The revisions address: (1) automatic signals for fan stoppage, 
(2) pressure recording devices, and (3) main mine fan monitoring 
systems.
    Paragraph (a)(3) of Sec. 75.310, like the proposal, requires each 
main mine fan to be equipped with an automatic device that gives a 
signal at the mine when the fan either slows or stops. The existing 
rule does not specify where the signal is to be given. Commenters 
supported the proposal stating that a signal alarming at a location 
away from the mine site would rely on overland communication lines to 
transmit the signal, with the person receiving the signal then 
notifying the mine. These overland communication lines are subject to 
weather and other potential sources of damage, which could result in a 
disruption of the communication. Other commenters objected to the 
proposal, however, stating that the ability of a mine operator to 
consolidate monitoring of several mines at one single location is a 
very efficient and cost-effective practice and should not be 
arbitrarily prohibited. Further, they stated that there would be 
absolutely no delay in contacting the miners from this central location 
should a fan malfunction occur. For clarity and for increased safety, 
the final rule requires that the signal be given at the mine. MSHA 
believes that in the case of a fan stoppage, this will assure more 
timely notice to miners, and hence, a more effective safety response. 
The requirement that the signal be given at a surface location at the 
mine does not preclude the signal from also being given elsewhere, such 
as at a central office, as long as it is given at the mine.
    Paragraph (a)(3) of Sec. 75.310 requires that a responsible person, 
designated by the operator, shall always be at a surface location at 
the mine where the signal can be seen or heard while anyone is 
underground. In addition, the responsible person must be provided with 
two-way communication with working sections and with other established 
locations where persons are normally assigned to work. Commenters 
supported the proposal stating that the changes provide clarification 
and specificity. Other commenters agreed with the proposed concept of 
two-way communication but felt that the wording, ``established 
locations where persons are normally assigned to work'' is ambiguous 
and subject to misinterpretation. Some commenters 

[[Page 9768]]
objected to the proposed requirement stating that (1) it is redundant 
of Sec. 75.1600 Communications; (2) properly the subject of a separate 
rulemaking under Sec. 75.1600 or; (3) it is vague, ambiguous, or 
subjective. Section 75.1600 only requires two-way communication between 
the surface and working sections and does not identify that this 
communication must be provided to a location where a person can see or 
hear the fan alarm signal. Commenters suggested that the requirement be 
revised to more specifically quantify locations where persons are 
normally assigned to work. MSHA recognizes that, as proposed, the 
standard might result in misinterpretation and the final rule has been 
reworded to read, ``* * * two-way communication with working sections 
and work stations where person(s) are routinely assigned to work for 
the majority of a shift.''
    Some, but not all, outby areas where two-way communication would be 
required by the final rule include; shops, attended belt transfer 
points, attended rail car loading points, and attended underground coal 
storage bins and hoppers. It is not intended that this communications 
capability be provided in areas where secondary roof support is being 
installed or where rock dust is being applied, or at unattended 
underground pumps, or in areas such as return air courses, bleeder 
entries and conveyor belt haulageways other than at belt transfer 
points. The requirement that two-way communication be provided to work 
stations where persons are routinely assigned to work for the majority 
of a shift is intended to help assure that these persons receive prompt 
notification of fan stoppages. Because these work stations are off the 
working section, a lack of communication capabilities could result in 
delays in notification and therefore delays in egress from the mine.
    Paragraph (a)(4) of the existing rule requires that main mine fans 
be equipped with a pressure recording device or with a main mine fan 
monitoring system but exempts from this requirement mines permitted to 
shut down main mine fans under Sec. 75.311.
    The final rule eliminates this exemption and requires that all main 
mine fans be equipped with a pressure recording device or a main mine 
fan monitoring device. For mines not currently required to have such a 
device, MSHA has provided for a 1 year phase in period to allow mine 
operators time to effectively plan and implement the necessary changes. 
One commenter suggested that all main mine fans at all mines be 
required to operate continually and further suggested that all main 
mine fans be equipped with pressure recording devices and main mine fan 
monitoring systems. In support of this suggestion, the commenter stated 
that continuous fan pressure recording devices would have a positive 
impact on safety at these operations. Such devices will provide 
necessary information to operators and miners at operations affected by 
this change. MSHA has not included one commenter's suggestion that main 
mine fan monitoring systems be required for all main mine fans. While 
MSHA supports and encourages the use of this advanced technology the 
Agency does not believe that it is appropriate to mandate it for all 
mines because daily fan examinations coupled with pressure recording 
devices have proved to be adequate over the years. Also, MSHA does not 
adopt a suggestion that main mine fans at all mines be required to 
operate continuously.
    Paragraph (a)(4) of the final rule requires that when a pressure 
monitoring device is used in lieu of a pressure recording device, it 
must produce a continuous graph or chart of the fan pressure. A hard 
copy of the continuous graph or chart must be printed at regular 
intervals of not more than 7 days. This provision permits the use of 
relatively recent advances in technology for monitoring main mine fan 
pressure provided a continuous record of the fan pressure is provided. 
In the proposal, MSHA specifically solicited comments as to an 
appropriate polling frequency that would provide a record that is 
substantially continuous. In response to this request, one commenter 
proposed that a polling frequency of two seconds is necessary to take 
full advantage of available technology. This commenter stated that 
continuously means constant or unbroken and that a continuous record 
should require a polling frequency of not greater than 2 seconds. 
Another commenter, an instrument manufacturer, suggested that a one 
minute sampling interval is definitely feasible. Main mine fan 
monitoring, when used, is often part of a more comprehensive mine-wide 
atmospheric monitoring system (AMS), and to require that the fan be 
polled every two seconds could delay the polling of other important 
sensors. Additionally, because these pressure monitoring devices are 
intended to be used in lieu of the traditional circular pressure 
recorder they must provide a substantially equivalent record. 
Experience by MSHA engineers following mine explosions and during more 
routine ventilation survey work has shown that the accuracy to which a 
7-day, circular recording chart of the type normally used can be read 
is on the order of several minutes. MSHA would expect that the polling 
frequency for a pressure recording device used in lieu of a pressure 
recorder would be no more than one (1) minute.
    MSHA received a number of comments in response to the proposed 
requirement in paragraph (a)(4) that when a pressure recording device 
other than a circular pressure recorder is used, a hard copy of the 
continuous graph or chart be generated at not more than 7-day 
intervals. Comments ranged from requiring daily printouts to not 
requiring any printout except when requested by an Authorized 
Representative of the Secretary. In response to these comments, the 
final rule retains the requirement for a hard copy of the continuous 
graph or chart be generated at not more than 7-day intervals. In light 
of MSHA's stated position to permit records of examinations to be 
stored electronically, the final rule permits the record of main mine 
fan pressure to be stored electronically provided the record is secure 
and not susceptible to alteration.
    Paragraph (c) of Sec. 75.310 specifies requirements for main mine 
fan monitoring systems if used under Sec. 75.312. Commenters suggested 
that the requirements were repetitive, confusing, and would discourage 
mine operators from using monitoring systems which could provide more 
protection. MSHA believes that the requirements in paragraph (c) are 
necessary to effectively monitor a fan, particularly when these systems 
are used in lieu of daily fan examinations.
    Paragraph (c)(3) of Sec. 75.310 of the proposal would have required 
that main mine fan monitoring systems provide, on demand, a printout of 
the monitored parameters, including the mine ventilating pressure. 
Several commenters objected to the requirement that a printout be 
provided ``on demand.'' As interpreted by these commenters, this 
standard would require that the operator provide a printout at any time 
it is requested. As explained in the preamble to the proposal, ``* * * 
the monitoring system would be required to have the capability of 
providing (emphasis added), on demand, a printout of the information 
being monitored. This capability is intended to facilitate the review 
of the information by mine management required in Sec. 75.312(b).'' The 
commenters misinterpreted the purpose for the standard. MSHA 
recognizes, 

[[Page 9769]]
however, the merits of being able to obtain a printout within a 
reasonable period of time. Therefore, the final rule requires that a 
main mine fan monitoring system used to satisfy the requirements of 
Sec. 75.312 provide a printout of the monitored parameters, including 
the mine ventilating pressure, within a reasonable period, not to 
exceed the end of the next scheduled shift during which miners are 
underground.
    Paragraph (c)(5) of Sec. 75.310 requires that two-way communication 
be provided between a surface location at the mine where the signals 
from the fan monitoring system can be seen or heard and working 
sections and other established locations where persons are normally 
assigned to work for the majority of the shift. Except for minor 
editorial changes, this requirement is the same as the proposal. 
Comments on this proposal were the same as comments on proposed 
paragraph (a)(3). Several commenters supported the proposal stating 
that the changes provide clarification and specificity. Other 
commenters agreed with the proposed concept of two-way communication 
but felt that the wording, ``established locations where persons are 
normally assigned to work'' is ambiguous and subject to 
misinterpretation. Some commenters objected to the proposed requirement 
stating that (1) it is redundant of Sec. 75.1600 Communications; (2) 
properly the subject of a separate rulemaking under Sec. 75.1600 or; 
(3) it is vague, ambiguous, or subjective. Section 75.1600 only 
requires two-way communication between the surface and working sections 
and does not identify that this communication must be provided to a 
location where a person can see or hear the fan alarm signal. 
Commenters suggested that the requirement be revised to more 
specifically quantify locations where persons are normally assigned to 
work. MSHA recognizes that, as proposed, the standard might result in 
misinterpretation and the final rule has reworded the proposal to read, 
``* * * two-way communication with working sections and work stations 
where person(s) are routinely assigned to work for the majority of a 
shift.''
    Some, but not all, outby areas where two-way communication would be 
required by the final rule include; shops, attended belt transfer 
points, attended rail car loading points, and attended underground coal 
storage bins and hoppers. It is not intended that this communications 
capability be provided in areas where secondary roof support is being 
installed or where rock dust is being applied, or at unattended 
underground pumps, or in areas such as return air courses, bleeder 
entries and conveyor belt haulageways other than at belt transfer 
points. The requirement that two-way communication be provided to work 
stations where persons are routinely assigned to work for the majority 
of a shift is intended to help assure that these persons receive prompt 
notification of fan stoppages or other problems with the fan that might 
require withdrawal of miners. Because these work stations are off the 
working section, a lack of communication capabilities could result in 
delays in notification and therefore delays in egress from the mine.

Section 75.311 Main Mine Fan Operation

    The main mine fan provides the pressure that causes air to move 
through the mine to dilute and carry away explosive and toxic gases, 
dusts and fumes. As such it is the most important part of the 
ventilation system. Section 75.311 requires fans to be continuously 
operated to provide constant ventilation to underground areas and 
specifies precautions for planned fan stoppages. It also addresses the 
repair of main mine fans, monitoring of fan signal devices on the 
surface, and protection against fires around fans and intake air 
openings.
    The final rule revises paragraph (d) of Sec. 75.311, which 
addresses the notification of mine officials of any unusual variance in 
mine ventilation pressure and requires the prompt repair of electrical 
or mechanical deficiencies. The final rule requires immediate 
notification and the prompt institution of corrective action or 
repairs.
    Commenters suggested deletion of the word ``unusual'' maintaining 
that this term makes the requirement vague and subject to different 
interpretations. These commenters suggested substituting the phrase, 
``that could materially affect the safety and health of persons in the 
mine'' to describe the type of pressure variance that would require 
action. In making this recommendation, the commenters cited similar 
language in existing Sec. 75.324(a)(1) that, according to the 
commenters, is understood throughout the coal mining community. Section 
75.324(a)(1) concerns alterations of the main ventilation air current 
or any split of the main air current. The final rule does not adopt 
this recommendation. Minor fluctuations in fan operating pressure are 
normal; however, unusual changes can be indications of changes in fan 
operation or changes underground, such as roof falls or loss of 
ventilation controls, that require prompt attention and corrective 
action. In addition, MSHA has 25 years of experience with the phrase 
``unusual variances in mine ventilation pressure'' and is unaware of 
significant difficulties with this terminology.
    Commenters questioned what constitutes an ``electrical or 
mechanical deficiency'' for the purposes of Sec. 75.311. The purpose of 
the standard is to assure that a problem with main mine fans is 
corrected promptly and that the proper persons are notified that the 
problem exists. The types of electrical or mechanical deficiencies 
requiring action under paragraph (d) are those that can interfere with 
mine ventilation. In addition, MSHA has 25 years of experience with the 
phrase ``electrical and mechanical deficiencies'' and is, again, 
unaware of any significant difficulties with the use of this 
terminology during this time frame.
    Commenters also addressed the proposal that the ``mine 
superintendent, assistant mine superintendent, or mine foreman'' be 
notified immediately when an unusual variance in mine ventilation 
pressure is observed, or when an electrical or mechanical deficiency in 
a main mine fan is detected. The final rule does not retain the mine 
superintendent or the assistant mine superintendent as mine officials 
to be notified. Commenters stated that this provision provides a 
measure of safety to the miners by requiring that specific mine 
managers be notified of possible main mine fan problems, while the 
existing standard specifies that such a situation must be investigated. 
Other commenters, however, suggested that the persons identified for 
notification under the proposal may not be the most qualified to handle 
the problem. They also indicated that the notification requirement 
could unnecessarily delay appropriate action by other responsible 
persons. The commenters further stated that the mine superintendent or 
assistant mine superintendent may not be at the mine and that a 
certified person would be in charge who should be permitted to take the 
appropriate action. The proposed requirement that certain mine managers 
be notified immediately was not intended to require that these 
individuals personally take the necessary actions to respond to the 
problem with the main mine fan. Neither was it intended that they be 
notified of such a problem, to the exclusion of all others. The 
objective of the rule is to assure that the appropriate actions are 
taken as soon as possible. Additionally, notification of specified mine 
officials is intended to assure that those persons who are responsible 
for the mine are aware of the problem. The 

[[Page 9770]]
final rule, therefore, retains the requirement that certain mine 
managers be notified of any unusual variance in the mine ventilation 
pressure or if an electrical or mechanical deficiency of a main mine 
fan is detected.
    The final rule does, however, delete reference to notification of 
the mine superintendent or assistant mine superintendent. As discussed 
in relation to the countersigning of records, the mine superintendent 
is quite often not a certified person and is only periodically present 
at the mine. In addition, consistent with other sections of the final 
rule and recognizing that the term mine foreman is not used at some 
mines, the final rule requires that if an unusual variance in the mine 
ventilation pressure is observed, or if an electrical or mechanical 
deficiency of a main mine fan is detected, the mine foreman or 
equivalent mine official, or in the absence of the mine foreman or 
equivalent mine official, a designated certified person acting for the 
mine foreman or equivalent mine official shall be notified immediately. 
As with the proposal, the final rule requires that appropriate action 
or repairs shall be instituted promptly. It is not intended that the 
appropriate action or repairs be delayed until the mine foreman or 
equivalent mine official is notified.
    During a series of informational meetings held by MSHA following 
publication of the existing rule, questions arose concerning the 
operation of back-up fans. For informational purposes, the preamble to 
the proposal included a detailed discussion of questions about the 
operation of back-up fans under the ventilation regulations and 
solicited comments. MSHA did not propose any rule changes, nor does the 
final rule contain specific provisions for back-up fans. When a back-up 
fan operates in place of the main mine fan, the back-up fan is 
considered to be a main mine fan and all subpart D requirements for 
main mine fans are applicable.

Section 75.313 Main Mine Fan Stoppage With Persons Underground

    Section 75.313 was stayed by MSHA as explained in the introductory 
section of this preamble. Generally, this standard is concerned with 
protecting miners from the danger introduced when the main mine fan 
stops, such as when there is a loss of power. Under these 
circumstances, mine ventilation is interrupted, permitting gases such 
as methane to accumulate. These conditions can lead to an explosion 
ignited by electric circuits or the operation of equipment.
    Paragraph (a)(3) of the final rule requires that if a main mine fan 
stops, everyone shall be withdrawn from the working sections and from 
areas where mechanized mining equipment is being installed or removed. 
The language of the final rule is identical to the wording of stayed 
Sec. 75.313 (a)(3). An in-depth discussion of provisions concerning the 
installation and removal of mechanized mining equipment is presented in 
the General Discussion section of this preamble.
    The final rule revises paragraphs (c)(2), (c)(3), (d)(1)(i) and, 
(d)(1)(ii) of the stayed standard. Paragraphs (c)(2) and (c)(3) require 
that when a main mine fan stops with persons underground, the 
underground electric power circuits shall be deenergized and mechanized 
equipment shall be shut off. These rules further recognize an exception 
to facilitate miners' evacuation from the mine. The exception 
temporarily permits some circuits to remain energized and some 
mechanized equipment to not be shut off, provided these circuits and 
mechanized equipment are necessary to withdraw persons from the mine 
and are located in areas where methane is not likely to migrate to or 
accumulate. These circuits must be deenergized and the mechanized 
equipment must be shut off as persons are withdrawn. The final rule 
differs from the stayed standard by limiting the exception permitting 
the use of these circuits or equipment to areas where methane is not 
likely to migrate to or accumulate.
    Paragraph (d)(1)(i) requires that when a fan stoppage lasts for 
more than 15 minutes a preshift-type examination must be conducted 
before persons other than designated examiners, are permitted to enter 
any underground area of the mine. Examiners are permitted to re-enter 
the underground area of the mine from which miners have been withdrawn 
only after the fan has operated for at least 15 minutes unless a longer 
period of time is specified in the mine ventilation plan. Paragraph 
(d)(1)(ii) requires that when a fan stoppage lasts for more than 15 
minutes, underground power circuits are not to be energized and 
nonpermissible mechanized equipment is not to be started until a 
preshift-type examination is conducted, except that designated 
certified examiners may use nonpermissible transportation equipment in 
intake airways to facilitate the conduct of the required examination.
    Some commenters suggested that actions following fan stoppages are 
best handled on a mine-by-mine basis through a plan approval process. 
Along 

[[Page 9773]]
these lines, commenters suggested that the fan stoppage plan approval 
process previously used by MSHA should be used with only minor 
modification to assure that plans do not become standardized, that is, 
model the rule on a past standard with criteria for approval of fan 
stoppage plans. Other commenters, while supporting the concept of fan 
stoppage plans, proposed to tie the submission and approval of such 
plans to total mine ventilation surveys and computer simulations 
conducted by the operator every three months. According to one 
commenter the data provided by these surveys would be used to determine 
the adequacy of a fan stoppage plan.
    The final rule does not adopt the suggestions of the commenters for 
mine fan stoppage plans. One objective in this rulemaking is to reduce 
the need for paperwork, such as plans, where reasonable, uniform 
requirements can be developed. The final rule establishes the general 
requirement that after a fan stoppage lasting more than 15 minutes, 
mine power and equipment is to be shut down. However, experience shows 
that using transportation equipment to facilitate mine evacuation is 
often necessary, provided this is done where gas is not likely to 
accumulate, and circuits are deenergized on the way out of the mine.
    Some commenters suggested that the requirements in paragraphs 
(c)(2) and (c)(3) limiting the use of transportation equipment to areas 
and haulageways ``where methane is not likely to migrate to or 
accumulate'' are inconsistent with certain state laws. As support for 
this assertion, the commenters gave the example of the state of 
Illinois' requirements for evacuating mines following an interruption 
in ventilation, which does not expressly recognize limited use of power 
and equipment to facilitate evacuation. State mine safety laws, 
including Illinois', are similar to the final rule provisions for 
evacuation after a mine fan stoppage. As a general rule, state mine 
safety regulations that are more stringent than MSHA standards are not 
considered to be in conflict with federal regulations, and the more 
stringent safety requirement applies. In this case, if the Illinois 
regulation would not permit temporary use of power and equipment to 
facilitate evacuation, then the state law would not be inconsistent 
with MSHA.
    Several commenters objected to the wording, ``where methane is not 
likely to migrate to or accumulate,'' in paragraphs (c)(2) and (c)(3), 
as being vague. Other commenters stated that the rule's requirement was 
simply good practice that would be heeded by prudent mine managers. 
MSHA agrees that the terms and objectives of the final rule are 
understood in the mining community, and believes that the determination 
of whether methane may migrate from adjacent areas and enter travelways 
and haulageways used by miners during withdrawal should be made on a 
mine-by-mine basis. Therefore, the final rule retains the exception 
that power circuits may remain energized and mechanized equipment may 
be operated only if located in areas where methane is not likely to 
migrate to or accumulate.
    Some commenters stated that history does not support the need for 
the requirements of paragraphs (c)(2) and (c)(3). Mine fan stoppages 
unquestionably result in the existence of unventilated areas and may 
result in highly hazardous methane accumulations. Although there have 
been a limited number of ignitions/explosions directly attributable to 
the operation of transportation equipment during a fan stoppage, the 
true measure of the potential hazard addressed by this standard can be 
seen in the ignitions and explosions that were the result of the 
operation of transportation equipment in unventilated areas. Examples 
of such types of accidents include: The 1972 Itmann No. 3 explosion, in 
which 5 miners died; the 1976 Scotia Mine explosion, in which 15 miners 
died; the 1982 Virginia Pocahontas No. 6 Mine explosion in which 1 
miner was injured; the 1983 McClure No. 1 Mine explosion, in which 7 
miners died; the 1983 Homer City Mine explosion in which a mine 
examiner was killed; the 1983 Greenwich Collieries No. 1 Mine explosion 
in which 3 miners were killed and 4 miners were injured and; the 1993 
explosion at the Buck Mountain No. 2 Mine in which 3 miners were 
injured. Given this history of explosions, it would not be prudent to 
permit electric circuits to remain energized and mechanized equipment 
to be operated in areas or haulageways where methane is likely to 
migrate to or accumulate during a fan stoppage.
    One commenter stated that the in-mine test necessary to determine 
the likelihood of methane migration could only be done with the fan 
stopped. The commenter questioned whether miners would be permitted 
underground during the tests. To the extent the tests require the main 
mine fan to be turned off, persons would be allowed underground to 
evaluate the effect of the fan stoppage or restart.
    Paragraphs (d)(1)(i) and (ii) address safety precautions for 
reentering the mine after ventilation is restored. Key objectives of 
these standards are the protection of the examiners and the safety of 
miners returning to work.
    As proposed, paragraph (d)(1)(i) would have required that when a 
fan stoppage lasts for more than 15 minutes a preshift- type 
examination be conducted covering the requirements of Sec. 75.360(b) 
through (e) before persons, other than designated examiners, enter any 
underground area of the mine. Commenters suggested that to provide the 
level of protection desired, a complete preshift examination, including 
the certification and recordkeeping requirements of Sec. 75.360(f) 
through (g), should be required. Commenters pointed to the need for 
miners reentering evacuated areas to be able to determine if the area 
had been examined and urged that the final rule require the examiner to 
certify by initial, date and time the areas examined.
    MSHA agrees that clear notice to miners about which areas have been 
examined is necessary and consistent with the objectives of the rule. 
The final rule, therefore, adopts the proposal. A record of the 
hazardous conditions found by examiners is required under Sec. 75.363 
of the final rule. This record serves the purpose of providing mine 
management with the information necessary relative to the existence and 
correction of hazardous conditions in the mine. The final rule 
incorporates these requirements by specifying that the scope of the 
examination be conducted as described in Sec. 75.360(b) through (e).
    Under paragraph (d)(1)(i) no one other than designated certified 
examiners would re-enter any underground area of the mine until the 
entire examination is completed. Commenters suggested that paragraph 
(d)(1)(i) be revised to permit partial examinations following fan 
stoppages and restarts under certain conditions. Under this suggested 
approach, the examination would focus on the effectiveness of the 
mine's ventilation system and methane accumulations in travelways, work 
places or other areas where miners will work following the interruption 
of ventilation. One commenter further suggested that an exception to 
this examination be provided for noncoal producing shifts, where 
persons are to work in the shaft, slope, drift, or on the immediate 
shaft or slope bottom area. The commenter suggested the examination 
following a fan stoppage could be limited to this area.
    The final rule does not adopt this approach. Limiting the scope of 
examinations following an interruption in mine ventilation to general 

[[Page 9774]]
ventilation effectiveness and methane accumulation would not focus on 
likely areas of concern. For example, no examination for hazards would 
be required, and no air measurements to determine if the air is moving 
in its proper direction and at its normal volume would be required. As 
to the area of the mine required to be examined, only those places 
where miners will return to work and the route of travel used to reach 
these places must be examined. Thus, the final rule is sufficiently 
flexible to meet the commenter's concerns about non- coal producing 
shifts.
    A question arose during public meetings as to the meaning of the 
term on-coming shift in Sec. 75.360 when applied to Sec. 75.313. For 
the purposes of Sec. 75.313(d)(1)(i) and (ii) the term ``persons on the 
on-coming shift'' is interpreted as meaning persons on the shift on 
which the fan is restarted. If a fan outage extends from one shift into 
another, a preshift examination as required by Sec. 75.360 must be 
completed before any person, except certified examiners designated to 
conduct the examination, enters the mine.
    Commenters also suggested that the final rule specify a minimum 
time for the fan to run before examiners re-enter the mine so that 
examiners are not unduly exposed to danger. Several commenters observed 
that this is a general practice in the industry.
    MSHA agrees that an important measure of safety is gained by 
allowing the mine fan to run sufficiently long to begin reventilating 
the mine before anyone enters. The final rule, therefore, provides 
designated certified examiners shall enter the underground area of the 
mine from which miners have been withdrawn only after the fan has 
operated for at least 15 minutes unless a longer period of time is 
specified in the approved mine ventilation plan. The 15 minute 
provision will permit re- ventilation of entries in which examiners 
will travel to take place and the examiners will then be traveling into 
the mine in fresh air.
    Proposed paragraph (d)(1)(ii) would have required that when a fan 
stoppage lasts more than 15 minutes underground power circuits are not 
to be energized and nonpermissible equipment is not to be started until 
a preshift-type examination is completed. Commenters objected to the 
proposal for various reasons. One commenter suggested that before power 
is permitted to be energized a complete ventilation survey should be 
required. Other commenters focused on the practical considerations 
involved in conducting examinations and urged that use of 
nonpermissible equipment for the transportation of examiners be 
permitted.
    As revised, paragraph (d)(1)(i) requires that the main fan when 
restarted run for at least 15 minutes so that restoration of mine 
ventilation is underway before anyone enters the mine. Once this is 
accomplished, electrical circuits in shafts and slopes can be energized 
safely as these areas are the first places to be reventilated by fresh 
air. Accordingly, the final rule permits these circuits to be re-
energized after the mine fan has run for at least 15 minutes.
    The final rule also permits examiners to use nonpermissible 
equipment for transportation during the examination. The proposal would 
have prohibited this practice. Some commenters supported the proposed 
prohibition citing two mining accidents involving nonpermissible 
equipment in unventilated areas. Other commenters objected to the 
proposal not to allow the use of nonpermissible equipment to facilitate 
examinations following the restart of a main mine fan. These commenters 
stated that travelways and equipment roadways can be examined and 
tested for the presence of methane, the results of the examination 
called out, and typical nonpermissible transportation equipment placed 
into operation to expedite the examination of the mine.
    After considering all of the comments, MSHA has revised the 
proposal and the final rule permits the use of nonpermissible 
transportation equipment, in intake airways, to facilitate making the 
examinations after an interruption in mine ventilation. Using 
nonpermissible equipment in this fashion, in nonventilated areas, has 
been a demonstrably safe practice for many years in the industry. In 
addition, the requirement of running the fan for 15 minutes before 
reentering the mine, together with keeping the transportation equipment 
in the intake airways where the main ventilating current travels first, 
provides the desired level of safety.
    Under proposed paragraph (d)(2), if ventilation was restored to the 
mine before miners reached the surface, all miners would have been 
required to continue traveling to the surface. As proposed, designated 
certified examiners would have been permitted to remain underground for 
the purpose of beginning the required examination. The final rule does 
not adopt the proposal and retains the language of the existing 
standard.
    While supporting the requirement that miners continue to the 
surface after a fan is restarted, some commenters objected to 
permitting certified persons to remain underground. These commenters 
also took the position that once a fan has been off for more than 15 
minutes, all efforts to restart the fan should be suspended, unless it 
is known that it is safe to restart the fan. Other commenters expressed 
significantly different views on both issues. A number of commenters 
supported restarting the fan as soon as possible because the longer it 
is off, the greater the potential hazard. MSHA concurs with this 
reasoning and the final rule adopts this approach.
    On the issue of requiring the evacuation to continue once it has 
begun until the fan is restarted, even when ventilation is restored, a 
number of commenters objected that such a requirement would result in 
unnecessary delays and may result in additional safety risks. One 
commenter stated that the proposal would not allow for the variables 
that exist from mine to mine. Several commenters suggested that if the 
operator has reason to believe that the time frame of the fan stoppage 
would be less than the travel time or equivalent, the dangers of 
traveling outby into possible pockets of dangerous gas buildup (or 
other travel hazards) far outweigh the dangers of staying on the 
section in intake air back from the face. This would also allow the 
miners to remain on the section and proceed to the working places after 
the fan has restarted and the working places have been examined by a 
certified person.
    MSHA disagrees with this position. In some mines, the time to 
travel from the outside to the working sections can approach 1 hour. 
Following the approach suggested, miners would remain on the section in 
an unventilated mine for up to 1 hour. If at the end of this time 
ventilation is still not restored, it is unclear whether the miners 
then proceed to the surface, traveling through the same area the 
commenter suggested might be hazardous some 45 minutes before.
    The commenters stated further that, ``Forcing miners to walk out of 
the mine could take hours and unnecessarily delay the restoration of 
ventilation and resumption of operations.'' While there may be 
instances where the time required to withdraw miners is increased, the 
requirements in paragraphs (c)(2) and (c)(3) have no impact on the 
restoration of ventilation. In fact, MSHA's position is that 
ventilation should be restored as soon as possible following a fan 
stoppage.
    Lastly, a number of commenters suggested that when ventilation is 
restored during evacuation, miners should be permitted to remain where 

[[Page 9775]]
they are and return to working areas after an examination of inby areas 
is completed. These commenters stated that no additional measure of 
safety is gained by requiring miners to continue to the surface if 
ventilation has been restored and the area in which the miners are 
located is free of hazards. MSHA agrees and has retained the language 
of the existing rule. By retaining the existing language, the general 
practice of miners stopping their evacuation and waiting for examiners 
to complete their work will continue. Under this approach, miners 
remain in a safe location while ventilation of the mine is restored. 
They do not return to any area of the mine until it has been determined 
to be safe. The final rule does not prevent mine operators from having 
miners continue to the surface if they so choose. Regardless of whether 
miners remain where they are or continue to the surface, paragraph 
(d)(1)(i) of the final rule requires that the fan operate for at least 
15 minutes before the examination of the areas from which miners have 
withdrawn is examined.

Section 75.320 Air Quality Detectors and Measurement Devices

    Section 75.320 establishes the standards for the devices relied 
upon to test for the presence of methane and other dangerous gases that 
can accumulate in a mine. It generally requires that these devices be 
approved and maintained in permissible and proper operating condition.
    The final rule adds a new paragraph (e). It requires that 
maintenance of instruments required by paragraphs (a) through (d) of 
Sec. 75.320 to detect and measure air quality be done by a trained 
person. The final rule does not include the proposal that before each 
shift care shall be taken to assure the permissible condition of the 
air quality detectors and other measurement devices to be used during 
the shift. MSHA has concluded that this requirement would have been 
redundant with paragraph (a) and is unnecessary. The final rule permits 
an operator to send instruments to a repair facility or to the 
manufacturer for regular servicing. Commenters at the informational 
meetings and in later discussions on the existing rule stated that 
maintenance by trained persons should be specified and that requiring 
only that air quality detectors and other measurement devices be 
maintained in permissible condition would not be sufficient. They 
stated that without a requirement for maintenance to be done by a 
trained person, similar to that which existed in the previous standard, 
a person with less than the necessary understanding of the instrument 
and the permissibility requirements might be assigned the task.
    Several commenters suggested that the requirements of paragraph (e) 
are redundant with general requirements found elsewhere in the 
standards and are unnecessary. Other commenters felt that the current 
performance standard is adequate, but that the meaning of ``assure'' is 
unclear. Still other commenters indicated that the assurance of 
permissibility is properly the responsibility of the user. One 
commenter noted that the instruments are intrinsically safe and that 
the manufacturer's instructions are sufficient. MSHA agrees that the 
general requirement under paragraph (a), together with requiring 
trained persons, is adequate.
    Another commenter suggested that a formal written maintenance 
program be required. Under this suggestion, the program would be 
subject to MSHA approval and would include records of all maintenance 
and calibrations to be made by the end of the shift. This commenter 
also suggested that existing paragraph (a) be revised to provide for 
more frequent calibration by inserting the phrase ``* * * or more often 
if necessary * * *.'' This suggestion has not been adopted since 
compliance with the proper operating and permissibility provisions of 
paragraph (a) would result in more frequent calibration, if necessary. 
MSHA notes that under the previous standard, there was no written 
maintenance program required nor were records required. MSHA believes 
that experience under both the previous and existing standards 
demonstrates that, with the addition of paragraph (e), maintenance and 
calibration is appropriately addressed in the final rule and safety is 
not reduced.
    Several commenters agreed with the proposal for a ``trained'' 
person to maintain air quality detectors and measurement devices. These 
commenters suggested that the trained person be defined as a person 
designated by the operator who has received training through experience 
in maintenance of the instrument, has been trained by an experienced 
person, or one who has received training by or through the instrument 
manufacturer. MSHA has not adopted this suggestion since the operator 
should have some flexibility as to the mode of training. The 
requirement that the person performing the maintenance must be trained 
is intended to mean that the person be capable of doing the required 
maintenance, not that they receive a specific course of instruction in 
what to do.
    Commenters suggested that maintenance and calibration requirements 
should parallel those proposed under Sec. 75.342 for machine-mounted 
methane monitors. They suggested that, because the detectors and 
monitors perform similar functions, the requirements should be similar. 
The final rule does not adopt this suggestion. The methane monitoring 
instruments under this standard and those governed by Sec. 75.342 are 
subject to different mining conditions. For example, machine-mounted 
monitors must be calibrated and maintained underground, on the 
equipment on which they are installed and on working sections. This 
calibration must also be scheduled within production timetables. 
Handheld detectors and measurement devices, however, are removed from 
the mine and are maintained and calibrated in surface environments. 
Calibration and maintenance of handheld detectors is usually done 
during shifts when the instruments are rotated out of service. Thus 
machine-mounted monitors are calibrated and maintained under more 
strenuous conditions than handheld detectors.
    One commenter suggested that written records of all maintenance and 
calibration should be required. The commenter further suggested that: 
Each operator submit a written maintenance program to MSHA for approval 
and provide a copy to the miner's representative; the written program 
specify training to be provided; records be completed by the person 
performing maintenance and be countersigned by the mine foreman within 
24 hours; and that records be maintained for one year and be made 
available to MSHA and the representative of the miners. These 
additional requirements were not included in the proposal and are not 
adopted in the final rule. The requirements contained in the final rule 
adequately address and are appropriately related to the concerns 
relative to maintenance, calibration, permissibility, and the general 
condition of air quality detectors and measurement devices.

Section 75.321 Air Quality

    The primary function of a mine ventilation system is twofold, to 
remove hazardous gases such as methane, and to provide miners with an 
respirable environment in areas where they are required to work or 
travel. As discussed in the introductory section of this preamble, 
Sec. 75.321 of the existing standard was stayed by the United States 
Court of Appeals for the District of Columbia Circuit as it pertains to 
bleeder entries. The final rule, in 

[[Page 9776]]
Sec. 75.321, addresses acceptable levels of oxygen and carbon dioxide 
in areas of a mine, including areas of a bleeder entry, where persons 
are required to work or travel.
    Paragraph (a)(1) continues a basic air quality requirement that has 
been in place since 1970 that air in areas where persons work or travel 
contain at least 19.5 percent oxygen and not more than 0.5 percent 
carbon dioxide, and the volume and velocity of the air current in these 
areas be sufficient to dilute, render harmless, and carry away 
flammable, explosive, noxious, and harmful gases, dusts, smoke, and 
fumes. Paragraph (a)(2) applies the same requirement for oxygen, 19.5 
percent, for the air in areas of bleeder entries and worked-out areas 
where persons work or travel. The final rule does not require the 
carbon dioxide level of 0.5 percent to be applied to bleeder entries 
and worked-out areas. Rather paragraph (a)(2) requires that the carbon 
dioxide levels in the air in bleeder entries and worked-out areas where 
persons work or travel not exceed 0.5 percent time-weighted average 
(TWA) and 3.0 percent short-term exposure limit (STEL).
    MSHA interpreted former Sec. 75.301 to require at least 19.5 
percent oxygen and no greater than 0.5 percent carbon dioxide in 
bleeder systems where persons work or travel. It was MSHA's intent that 
existing Sec. 75.321 would necessitate compliance with these levels 
where persons would be exposed in bleeder entries and in worked-out 
areas. However, the application of this provision to bleeders and 
worked-out areas was stayed by the United States Court of Appeals 
pending the outcome of litigation addressing the promulgation of the 
existing rule. MSHA continues to believe that providing necessary air 
quality is essential to protect miners and examiners whenever they work 
or travel in bleeder entries and worked-out areas. Therefore, the final 
rule includes a new provision specifying that the air in bleeder 
entries and worked-out areas where persons work or travel contain at 
least 19.5 percent oxygen, and that carbon dioxide not exceed 0.5 
percent TWA and 3.0 percent STEL. A TWA is the time-weighted average 
concentration for a normal 8-hour workday and a 40-hour workweek. A 
STEL is the maximum time-weighted average concentration to which miners 
can be exposed for a continuous period of up to 15 minutes. Commenters 
noted an error in the preamble to the proposal with respect to the time 
an individual can be exposed to concentrations between the TWA and the 
STEL. MSHA intends to apply TWA and STEL levels in a manner consistent 
with the Air Quality rulemaking. The levels for carbon dioxide in the 
final rule for areas where persons work or travel in bleeder entries 
and worked-out areas are identical to the levels contained in MSHA's 
proposed Air Quality standards for coal and metal and nonmetal mines 
and the 1992 Threshold Limit Values (TLVs) as specified by the American 
Conference of Governmental Industrial Hygienists (ACGIH).
    Some commenters suggested that other changes be included in the 
final rule. First, they recommended that the permissible minimum oxygen 
level for bleeders and worked-out areas be lowered from 19.5 percent to 
18 percent. Second, they suggested that the requirements that apply to 
bleeders and worked-out areas be expanded to include airways associated 
with bleederless mining areas. The rationale given for this second 
recommendation was that the conditions in these airways are similar to 
bleeders. In light of the ongoing Air Quality rulemaking, MSHA is not 
at this time clarifying existing Air Quality standards except those for 
worked-out areas and bleeder entries.
    Commenters for the most part agreed with the change relative to 
carbon dioxide although one commenter indicated that there was no need 
for any standard. Bleeder entries and worked-out areas are required to 
be traveled or evaluated at least weekly. Generally, this is done by a 
person traveling alone who is often required to be in the bleeder 
entries or worked-out areas for an extended period. The purpose of this 
standard is to protect miners, not to regulate air quality where 
persons are not exposed. Therefore, if examinations are performed 
remotely or if persons making the examination can otherwise remain in 
air that meets the requirements of the standard, oxygen and carbon 
dioxide levels at bleeder connectors and bleeder evaluation points 
would not have to meet the concentrations required by the final rule.
    According to the National Institute for Occupational Safety and 
Health (NIOSH) of the U.S. Department of Health and Human Services 
(NIOSH Respirator Decision Logic, May 1987), 19.5 percent oxygen 
provides an adequate amount of oxygen for most work assignments and 
incorporates a safety factor. Also according to NIOSH, the safety 
factor is needed because oxygen-deficient atmospheres offer little 
warning of danger. In the NIOSH publication, ``A Guide to Safety in 
Confined Spaces,'' (page 4), a chart is presented that indicates that 
19.5 percent oxygen is the minimum level for safe entry into an area, 
and that at a level of 16 percent, judgement and breathing are 
impaired. The American National Standards Institute (ANSI), in ANSI 
Z88.2-1992, ``American National Standard for Respiratory Protection'' 
recognizes that at 16 percent oxygen there is an impairment in the 
ability to think and pay attention, and a reduction in coordination. 
ANSI recognizes that at 19 percent oxygen there are some adverse 
physiological effects.
    The need for regulating the oxygen level where persons work or 
travel in bleeder entries is illustrated by two mining accidents. One 
of these accidents resulted in the death of a mine examiner and the 
second resulted in the near death of two individuals, one of whom was a 
mine examiner. Mine examiners are, through training and experience, the 
individuals best able to identify the hazards associated with 
irrespirable atmospheres. The first accident occurred at the Arclar 
Mine in Equality, Illinois in 1989. Prior to implementation of the 
existing standard, a mine examiner entered a worked-out area that was 
posted with a danger sign and was asphyxiated. Under the existing 
regulation, ventilation or sealing of this area, rather than posting, 
would be required. Because the area was not sealed, the existing 
regulation would require the area to be examined during the weekly 
examination. The final rule would require that the route of travel for 
the examiner contain at least 19.5 percent oxygen. Had the final rule 
been in place when the examiner entered the worked-out area, the 
accident may have been avoided.
    The second accident, although not in a bleeder entry or worked-out 
area, is illustrative of what can happen when individuals, including 
mine examiners, are subjected to oxygen deficient air. In 1983 at the 
Bird No. 3 Mine in Riverside, Pennsylvania, an assistant mine foreman, 
a certified person, entered the mine for the purpose of conducting an 
examination. After traveling approximately 1100 feet, the examiner 
became dizzy, noticed that his flame safety lamp had extinguished and 
withdrew approximately 200 feet where he sat down and apparently became 
unconscious. A second individual upon entering the area in search of 
the examiner also became dizzy but was able to withdraw to a location 
that was not oxygen deficient. When the mine examiner regained 
consciousness, his cap lamp battery had discharged and he traveled in 
total darkness until he encountered a mine rescue team. Air samples 
collected in the area where the mine examiner first became dizzy 

[[Page 9777]]
indicated an oxygen level of about 16.8 percent, while other samples 
collected nearby indicated oxygen concentrations of nearly 20 percent.
    Because mine examiners are required to work or travel in areas 
where oxygen-deficient air could occur without warning, and they 
normally travel and work alone, there must be a requirement that 
provides them the protection necessary for the performance of their 
duties under these conditions. It is important that the level for 
oxygen be established above that identified as resulting in impaired 
judgement because it is essential that individuals traveling in these 
areas remain highly alert. The hazards that can exist in bleeder 
entries and worked-out areas include elevated methane levels, poor 
footing, loose and unstable roof, and water accumulations. For this 
reason, the final rule adopts a minimum level of oxygen of 19.5 percent 
as recommended by NIOSH.
    MSHA is also concerned with the effects of other gases often found 
in bleeder entries. Section 75.322 of the existing regulation limits 
the concentration of noxious or poisonous gases to the current (1971) 
TLV's as adopted and applied by the ACGIH. Section 75.322 specifically 
excludes carbon dioxide since it is covered by Sec. 75.321. However, so 
the mining public will clearly understand the application of the 
regulation, the final rule establishes a separate standard for carbon 
dioxide levels for areas where persons work or travel in bleeder 
entries and worked-out areas. The levels set by the final rule, 0.5 
percent TWA and 3.0 percent STEL, when considered in conjunction with 
the requirements of Sec. 75.322 and the requirement for oxygen, will 
provide persons working or traveling in these areas with a safe and 
healthful working environment. MSHA recognizes that the effects of 
carbon dioxide are both chronic and acute and, therefore, sets both a 
TWA and a STEL. NIOSH, in recommending a standard for carbon dioxide, 
also recognized this and recommended a similar approach. The NIOSH 
recommendation, made in a Criteria Document published in 1976, proposed 
a TWA concentration of 1.0 percent and a ceiling value of 3.0 percent 
not to exceed 10 minutes. In making this recommendation, NIOSH 
recognized that there are additive stress effects of increased carbon 
dioxide concentrations and exercise. As support for this, the NIOSH 
document cites research that showed that healthy, trained subjects 
exposed to 2.8 to 5.2 percent carbon dioxide at maximum exercise levels 
experienced respiratory difficulty, impaired vision, severe headache, 
and mental confusion; three subjects collapsed.
    During rulemaking on the proposed air quality standard, NIOSH 
recommended a 0.5 percent TWA and a 3.0 percent STEL. NIOSH made a 
similar recommendation to the Occupational Safety and Health 
Administration during that Agency's permissible exposure limit 
rulemaking. Given the work environment in bleeder entries and worked-
out areas, as described earlier, MSHA believes that the regulatory 
approach to bleeders and worked-out areas provided by the final rule is 
necessary and appropriate. In addition to examiners, other miners may 
be required to work in the bleeder entries and worked-out areas, 
performing duties such as installing roof support, pumping water, 
recovering materials or adjusting ventilation. The levels established 
in the final rule would provide these miners with the necessary 
protection.

Section 75.323 Actions for Excessive Methane

    Section 75.323 establishes the actions that must be taken when 
methane reaches certain levels. Methane is the most dangerous gas 
encountered by miners working underground. When the level of methane 
reaches 5.0 percent it is explosive. Section 75.323 generally 
establishes action levels below this lower explosive limit to permit 
appropriate actions to be taken by mine operators in order to prevent 
an explosion.
    The final rule adopts the proposal for Sec. 75.323. In doing so, it 
revises paragraphs (b)(1)(ii), (c)(1), and (d)(2)(i) of the existing 
standard. The rule clarifies that corrective actions at specified 
methane levels must be taken ``at once'' and provides that actions for 
excessive methane include areas where mechanized mining equipment is 
being installed or removed. MSHA believes that final rule Sec. 75.323 
increases the protection afforded by the existing standard.
    Initially, the need for clarification was raised during 
informational meetings and subsequent discussions after publication of 
the existing rule. As discussed below, the final rule retains the 
language of the proposal which is identical to the wording of the 
previous standard.
    Some commenters indicated that delays in remedial actions to reduce 
methane were being experienced at some mines. These commenters 
attributed delays to the deletion of the phrase ``at once'' in the 
existing standard. These commenters also suggested that the phrase ``at 
once'' conveys the proper sense of urgency to correct the condition. 
Other commenters stated that the addition of the phrase ``at once'' 
does nothing to improve health or safety. MSHA has included the phrase 
in the final rule for clarity.
    Methane poses a significant hazard to miners when it is permitted 
to accumulate without corrective action being taken quickly. MSHA has 
always intended that corrective changes be made at once. The final rule 
revises paragraphs (b)(1)(ii), (c)(1) and (d)(2)(i) to require that 
these changes be made ``at once,'' the phrase used in former 
Secs. 75.308 and 75.309.
    Some commenters stated that the proposal, if literally enforced, 
would necessitate changes to be made before the cause or source of the 
increase in methane can be investigated. Other commenters stated that 
approvals must be obtained for many ventilation changes and that some 
changes require extended periods of time to complete. Operators may 
take those actions necessary to abate imminent dangers or hazardous 
conditions, or to safeguard persons and equipment. A part of this 
action would be a determination of the cause of the problem. MSHA knows 
of no case where an operator has been prohibited from a necessary 
correction for a methane problem pending a plan approval. However, in 
cases where intentional changes are made which could materially affect 
the safety and health of miners, approval is required before resumption 
of normal work if the changes affect the information approved in the 
mine ventilation plan. MSHA recognizes that some ventilation changes 
take time to accomplish and interprets the phrase ``at once'' as 
meaning that the work of making the necessary change to reduce methane 
levels begins immediately.
    One commenter questioned how the phrase ``at once'' would apply to 
a methane feeder which is encountered despite an appropriate and well 
thought out ventilation change. MSHA recognizes that methane feeders 
may be encountered unexpectedly. As long as a mine operators takes 
action as required by the standard, they will be in compliance.
    One commenter suggested that some MSHA personnel were improperly 
interpreting methane excursions above 1.0 percent to be violations of 
the standard. The commenter seemed to suggest the regulations should 
provide that the actions specified in Sec. 75.323 for excessive methane 
do not apply to concentrations detected on machine-mounted methane 
monitors. Other commenters indicated that the standard requires 
unnecessary ventilation 

[[Page 9778]]
changes in response to instantaneous increases caused by excessive 
methane liberation. MSHA recognizes that instantaneous methane monitor 
readings for machine mounted monitors may occasionally reach or exceed 
1.0 percent. Usually, these are short-lived and the monitor reading 
quickly falls below 1.0 percent, even before the machine operator can 
react. However, consistent monitor readings of 1.0 percent or more 
indicate a problem and should cause appropriate changes and 
adjustments. Repeated short duration increases above 1.0 per cent 
should also be cause for concern and may necessitate changes or 
adjustments to ventilation.
    With respect to paragraphs (b)(1), (b)(2), and (c)(1) some 
commenters stated that the mere presence of methane does not constitute 
a violation of a mandatory health and safety standard. MSHA agrees. In 
this context, one commenter suggested replacing the word ``present'' 
with ``detected.'' The commenter continued that an operator cannot 
possibly correct a methane problem until it has been detected, that the 
rule should reflect realistic expectations, and that the current term 
``present'' is meaningless. MSHA agrees that a methane problem cannot 
be corrected unless it has been detected and that the mere presence of 
methane does not constitute a violation. Only the failure to properly 
respond once being made aware of the presence of methane in excess of 
allowable levels is a violation. The standard requires that an operator 
properly conduct an examination; and if methane over 1.0 percent or 1.5 
percent is found, as applicable, corrective action must be taken at 
once.
    When 1.0 percent or more methane is present in a working place, an 
intake air course, or an area where mechanized mining equipment is 
being installed or removed, paragraph (b)(1)(i) of the final rule 
requires all electrical, diesel, and battery- powered equipment in the 
affected working place, intake air course, or other area, except for 
intrinsically safe AMS, to be deenergized or shut off. Deenergizing or 
shutting off of this equipment protects miners by preventing this 
equipment from providing ignition sources.
    One commenter suggested that non-intrinsically safe AMS equipment 
should be permitted to run under battery power when 1.0 percent or more 
methane is encountered. The commenter stated that the benefit derived 
through the system's operation outweighs the hazard of the non-
intrinsically safe system. The commenter continued that since the 
batteries will deplete quickly, little hazard would result, or in the 
alternative, each battery outstation could be monitored for methane and 
automatically trip at some set methane level. The final rule does not 
include this suggestion. Where excessive methane concentrations 
necessitate that power be deenergized, information from continued 
operation of the non-intrinsically safe system would not outweigh the 
potential ignition hazard. To permit operation of a non- intrinsically 
safe system in areas known to contain excessive levels of methane would 
be a departure from accepted, effective, and long standing safety 
practice.
    Several commenters objected to the requirement in paragraph 
(b)(1)(iii) that prohibits any work in the affected area until the 
methane is reduced to less than 1.0 percent. Commenters questioned 
whether the standard would prohibit an operator from taking steps to 
reduce the methane. The language must be given a reasonable 
interpretation and should be considered in context of the preceding 
requirement in paragraph (ii) that ``changes or adjustments shall be 
made at once * * * ''
    These requirements are virtually identical to those found in the 
previous standard which was in effect for over 20 years. MSHA is 
unaware of any instance where an operator was prohibited from 
correcting methane problems by such an application of the standard.
    Some commenters suggested adding a phrase to paragraph (b)(1)(iii) 
to read, ``No work other than removal of the accumulation shall be 
permitted * * * '' Similarly, MSHA believes that the suggested change 
is unnecessary and has not adopted it. MSHA experience indicates that 
the rule is well understood and has been properly applied.
    Other commenters thought that the standard, as proposed, would 
cause hasty, ill-advised changes to be made and would prohibit an 
investigation into the cause or source of the methane problem which 
could result in phased-in corrections. MSHA agrees that operators 
should seek long term solutions and should fully investigate the cause 
or source of methane accumulations. Investigation and long term 
corrections are not prohibited by the rule. However, the final rule 
does require that certain actions be undertaken at once to correct the 
short term or acute safety hazards resulting from accumulations of 
methane.
    If 1.5 percent or more of methane is present in a working place, an 
intake air course, or an area where mechanized mining equipment is 
being installed or removed, paragraph (b)(2) of the final rule requires 
persons to be withdrawn from the affected area. The presence of methane 
in these areas can pose a significant risk to miners and therefore 
their withdrawal from the affected area is essential to their safety. 
Paragraph (b)(2) also requires that all electric power to equipment in 
affected areas be disconnected at the power source. This prevents 
accidental energization of equipment and removes power from cables and 
circuits which may also be ignition sources. No other work is permitted 
in the affected area until the concentration of methane is less than 
1.0 percent. A conforming change is also made to paragraph (b)(2) by 
adding ``mechanized'' before mining equipment for consistency with 
other provisions of the rule.
    Comments were received which objected to the (b)(2)(ii) requirement 
that except for intrinsically safe AMS, electrically powered equipment 
in the affected area shall be disconnected at the power source. Some 
commenters suggested that this equipment should be simply 
``deenergized.'' These commenters stated that there was no need to 
disconnect the power source, that this could require belt drives, 
pumps, etc. to be physically disconnected where permanent connections 
have been made, which could result in a major unnecessary operation. 
MSHA has not adopted this suggested revision. MSHA issues numerous 
citations and orders for damaged power cables, trailing cables, and 
splices where the conductors are badly damaged or exposed. Each of 
these citations and orders represents the presence of a potential 
ignition source. Power cables would remain energized under these 
conditions as would be the case if the commenters' suggestion were 
adopted.
    There are several aspects of Sec. 75.323 which were not proposed 
for revision, but for which comments were received. Comments were 
received relative to the 1.0 percent action level in intake air 
courses. Commenters contended that Congress established an immutable 
methane limitation of 0.25 percent in intakes. Commenters stated that 
because Congress had expressly limited intakes passing openings to 
abandoned areas to 0.25 percent methane, that implicitly, all intakes 
were limited to 0.25 percent methane. However, the commenter then 
suggested adopting an intake action level for methane of 0.5 percent. 
MSHA notes that the methane levels were not proposed for revision and 
are not being revised under the final rule. The commenters, however, 
should refer to a discussion of this issue included in the 

[[Page 9779]]
preamble to the existing rule dated May 15, 1992.
    If 1.5 percent or more methane is present in return air, paragraph 
(d)(2)(i) would require changes or adjustments be made ``at once'' to 
the ventilation system to reduce the concentration of methane. Because 
of the hazards presented by accumulations of methane, MSHA believes 
that changes or adjustments should be made immediately and be made 
independent of the mine ventilation plan in the interest of safety. 
MSHA recognizes that some changes take time to complete. If operators 
begin ``at once'' to make the necessary changes and adjustments, they 
will be in compliance with the standard.
    MSHA received comments relative to Sec. 75.323 which, although were 
outside the scope of the rulemaking, demonstrate an incorrect 
understanding of the existing rule. The limitations on methane content 
and the associated actions required when excessive methane is 
encountered are important components of a safety program to protect 
underground miners. Therefore, several of these comments will be 
addressed so that the mining community will better understand these 
standards.
    First, one commenter objected to the existing requirements in 
Sec. 75.323(d). The commenter incorrectly stated that paragraph (d) 
permits normal operations with 1.5 percent methane in working places. 
Methane limits in working places and intake air courses is limited by 
Sec. 75.323(b). Paragraph (b) specifies actions if 1.0 percent methane 
is present, and withdrawal if 1.5 percent is present. Similarly, 
Sec. 75.323(c) limits methane between the last working place on a 
working section and where that split of air meets another split of air 
to 1.0 percent and requires withdrawal at 1.5 percent. Paragraph (d) 
modifies the requirement for that portion of the return split outby the 
section loading point and has no effect on methane either in working 
places or between the last working place and the point in the return 
opposite the loading point.
    One commenter indicated a preference for the language used in a 
previous MSHA regulation, Sec. 75.308-1. The previous standard 
restricted the changes or adjustments to increasing the quantity or 
improving the distribution of air in the affected working place to an 
extent sufficient to reduce and maintain the methane to less than 1.0 
percent. The existing rule establishes a performance standard that 
allows for several methods of compliance. One acceptable method of 
compliance is to limit the rate of production of coal to permit the 
existing ventilation system to maintain the level of methane below 1.0 
percent. In all cases, however, increasing the quantity or distribution 
of air continues to be an accepted means of reducing methane levels. No 
safety benefit would be derived from disallowing reduced coal 
extraction rates as a means of maintaining methane levels under 1.0 
percent.
    The final rule retains the language of proposed 
Secs. 75.323(b)(1)(i), 75.323(b)(1)(iii), and 75.323 (b)(2)(i) and 
(b)(2)(ii) which is identical to the wording of the existing standards. 
An in-depth discussion of the reproposal of provisions concerning the 
installation and removal of mechanized mining equipment is presented in 
the General Discussion section of this preamble.

Section 75.324 Intentional Changes in the Ventilation System

    This section addresses the precautions that must be taken when a 
significant change is made to the ventilation system. MSHA did not 
propose any change to existing Sec. 75.324 and is not making any 
revisions in the final rule.
    Questions had been raised concerning the language, ``materially 
affect the safety or health of persons in the mine'' that appears in 
the existing standard. The phrase is important in that it identifies 
those ventilation changes that require approval of the MSHA district 
manager under Sec. 75.370(c). MSHA regards it as impractical to follow 
a ``cookbook'' approach to identifying what will or will not require 
approval. Each particular circumstance is to be reviewed by the 
operator on its own merits. To illustrate the Agency's expectations, 
the following is a list of some examples of what MSHA considers 
intentional changes that would materially affect the safety or health 
of miners. These examples are not meant to include all possibilities, 
but are meant to provide some general guidance: adding a new shaft; 
bringing a new fan on line; changing the direction of air in an air 
course; changing the direction of air in a bleeder system; shutting 
down one fan in a multiple fan system; starting a new operating section 
with ventilating quantities redistributed from other sections of the 
mine; changing entries from intakes to returns and vice versa; and any 
change that affects the information required by Sec. 75.371, Mine 
ventilation plan; contents.
    Comments were specifically solicited on issues raised in the 
preamble discussion to the proposal. In response, written comments were 
received from one commenter. These comments were reinforced by several 
speakers at the public hearings. Other commenters indirectly referred 
to Sec. 75.324 and stated that the phrase, ``materially affect the 
safety or health of persons in the mine'' is accepted and understood by 
the mining community.
    One commenter suggested that the person designated by the operator 
to supervise ventilation changes should be a certified person that is 
knowledgeable of the mine's ventilation system. The results of changes 
to a complex ventilation system are not always easy to predict, and for 
that reason caution must be used when making significant changes to one 
air split or several air splits. The balance of splits can be affected 
and may result in air reversals, dead air spaces, or insufficient air 
flow in critical areas. For this reason, such changes must be evaluated 
by a certified person examining the affected areas to determine that 
the areas are safe before production is resumed. Therefore, the Agency 
believes that it is to be an unnecessary burden to also have 
ventilation changes supervised by a certified person. Thus, the 
suggestion of the commenter has not been adopted in the final rule.
    This commenter also suggested that the provisions of Sec. 75.324 
should apply to all intentional changes which alter the air current in 
any section or area of the mine by 10 percent or more, or by 9,000 cfm 
or more, whichever is less and that such change be considered to affect 
the entire mine. The commenter recommended the miners' representative 
be afforded the right to accompany the certified person to evaluate the 
effects of the ventilation change and that a preshift examination of 
the mine be conducted to assure that the mine is safe before electric 
power is restored.
    The commenter also suggested that a record be maintained of all 
ventilation changes to include the names of all persons involved with 
the change, the date and time of the change, and results and locations 
of air quality and quantity measurements taken both before and after 
the change. The commenter stated that the record should be made in an 
approved book within 24 hours of the change and that the record should 
be signed and countersigned. Finally, the commenter recommended that 
the mine ventilation map should be updated immediately after the 
ventilation change is made and that within 24 hours of the change, the 
updated map should be made available to the miners' representative and 
a copy sent to the district manager. Section 75.370(c) requires that 
any change to the ventilation system that alters the main 

[[Page 9780]]
air current or any split of the main air current in a manner that could 
materially affect the safety or health of the miners, or any change to 
the information required in Sec. 75.371 shall be provided to and 
approved by the district manager before implementation. The final rule 
requires that this information be provided to the miners' 
representative at least 5 days before submittal to the district manager 
(See Sec. 75.370 for full discussion). MSHA believes that this 
provision provides necessary protection for miners.
    One commenter stated that the standard is reactive and that MSHA 
routinely cites mine operators after a methane explosion or ignition. 
MSHA believes that the standard is designed to assure that operators 
are proactive and develop plans that prevent hazardous conditions. The 
Agency anticipates that with the clarification provided through this 
rulemaking, operators will obtain MSHA approval prior to making 
intentional ventilation changes that materially affect the safety and 
health of miners, thereby preventing potentially hazardous conditions. 
When questions arise as to whether an anticipated change requires prior 
approval, MSHA is available to provide guidance as to whether approval 
is necessary.

Section 75.325 Air Quantity

    The quantity of air in cubic feet per minute (cfm) is an important 
measure of underground coal mine ventilation. It is essential for 
miners' health and safety that each working face be ventilated by a 
sufficient quantity of air to dilute, render harmless, and carry away 
flammable and harmful dusts and gases produced during mining. An 
insufficient quantity of air at a working face could permit methane to 
accumulate and lead to an explosion. Section 75.325 generally 
establishes the quantities of air that must be provided and the 
locations underground where these quantities must be provided.
    Section 75.325(d) requires that areas where mechanized mining 
equipment is being installed or removed be ventilated and that the 
minimum quantity of air and the ventilation controls necessary to 
provide these quantities be specified in the approved mine ventilation 
plan. The final rule adds the word ``minimum'' to the phrase, 
``quantity of air'' that appears in the existing standard and the 
proposal. The existing standard was reproposed without change. An in-
depth discussion of the reproposal of provisions concerning the 
installation and removal of mechanized mining equipment is presented in 
the General Discussion section of this preamble.
    Only a few comments were received that were specific to paragraph 
(d). One commenter discussing Sec. 75.371(r) suggested that the 
quantity of air required by Sec. 75.325(d) to be specified in the plan 
should represent the ``minimum'' quantity to be provided and that the 
location specified should be identified as typical so as to give the 
mine the flexibility to adapt to conditions. This comment is consistent 
with MSHA's intent for the proposal and helps to clarify it. Therefore, 
the word ``minimum'' has been inserted into the final rule in both 
Sec. 75.371(r) and paragraph (d) of Sec. 75.325. Obviously, mine 
operators can have air quantities which exceed the minimum specified in 
the mine ventilation plan. MSHA agrees conceptually with a comment that 
the ventilation scheme shown in the plan should be representative of 
the method of ventilation to be used. However, MSHA does not adopt this 
comment because the plan must also be specific enough so that the 
operator, the miners, the representative of miners, and MSHA are 
assured that the areas are being adequately ventilated.
    Other commenters suggested that the total quantity of air to be 
delivered to a longwall needs to be specified in the mine ventilation 
plan. In support of the suggestion the commenter stated that the 
inclusion of the word ``total'' recognizes that some mines may use belt 
air at the set up or tear down phase while some intake air may be 
diverted to ventilate bleeders, battery chargers or compressors and, 
therefore, the total quantity of air being delivered to the longwall 
face should be the figure with which MSHA is concerned. The commenter 
stated further that the recommendation recognizes that conditions vary 
greatly from mine to mine, coal seam to coal seam, even from one 
longwall panel to the next panel of the same mine. The commenter added 
that while a specified amount of air can be delivered to a recovery 
face, and pressure can be placed on the gob, it is impossible to 
guarantee a specified volume or velocity of air at the recovery point.
    MSHA agrees that the total air quantity provided to a recovery face 
is of importance; however, the distribution of this air is also 
important. The volume of air being delivered to the longwall face 
during equipment removal is important because of the types of 
activities that occur (e.g. cutting and welding and the operation in 
some cases of considerable numbers of diesel powered vehicles) and the 
fact that it is along the face that the majority of miners work and 
where an ignition hazard exists. It is important to know exactly how 
areas where mechanized equipment is being installed or removed will be 
ventilated. Therefore, this suggestion has not been included and the 
rule.
    Commenters were concerned about the ventilation of a longwall face 
prior to the first gob fall. This type of concern should be handled 
through the mine ventilation plan. Paragraph (d) only deals with areas 
were mechanized mining equipment is being installed or removed and not 
where mining is in progress.

Section 75.330 Face Ventilation Control Devices

    The final rule adds a new paragraph (c) adopting the proposal 
language. The new paragraph (c) requires that when line brattice or any 
other face ventilation control device is damaged to an extent that 
ventilation of the working face is inadequate, production activities in 
the working place are required to cease until necessary repairs are 
made and adequate ventilation is restored. MSHA notes that before 
issuing a citation for a violation of this provision, an inspector 
would normally be expected to measure the air quantity to determine 
whether adequate ventilation is being maintained.
    Some commenters considered the proposed regulation redundant since 
operators must already maintain minimum air quantities at the face, 
thereby making repairs necessary to maintain the required quantity. 
Face ventilation controls are a critical feature of reliable 
ventilation. As such, maintaining these controls in good condition and 
making repairs necessary to restore ventilation is sound safety 
practice. To do less invites increased risk of a methane ignition and 
elevated respirable dust. Also on a practical level most miners on a 
working section do not have a means of measuring air quantities. 
However, miners can determine when ventilation controls are damaged 
appreciably and are likely to adversely affect the air quantity.
    One commenter indicated that entire working sections might be shut 
down to repair a ventilation control at any one face with no 
corresponding safety benefit. The final rule provides that ``production 
activities in the working place shall cease'' until adequate 
ventilation is restored. Unless elevated methane levels or some other 
problem existed, the entire section would not be shut down for repair 
of a ventilation control.
    Some commenters asserted that controls may be slightly damaged 
while still maintaining quantities in excess of 

[[Page 9781]]
the requirements at the face. Similarly, commenters worried that 
numerous citations would be issued based solely on the appearance of 
the controls, even though the minimum required face air quantities are 
exceeded. These commenters stated that the only reliable indicator is 
an air measurement.
    MSHA agrees that the only precise indicator of air quantity is a 
measurement. Accordingly, MSHA anticipates that noncompliance decisions 
will be based on air measurements which show ``ventilation of the 
working place is inadequate.'' However, ventilation controls which are 
in poor condition are likely to cue an inspector to conduct an air 
measurement.
    Other commenters generally expressed the view that the requirements 
of Sec. 75.330, even considering the proposed revision, are inadequate 
to fully address the issue of face ventilation. According to these 
commenters, additional requirements are needed, including: proper 
installation and maintenance criteria for face ventilation control 
devices, requirements for providing devices continuously from the last 
open crosscut to the working face, immediate repair of these devices if 
damaged by a fall or otherwise, providing sufficient space between the 
line curtain and the rib and maintaining the area free of obstructions, 
and minimizing leakage while providing installations which permit 
traffic to pass without adversely affecting ventilation. Further, the 
commenters asserted that only cumulatively can the desired result be 
obtained through these requirements and that additional requirements 
would empower individual miners to take corrective actions when needed.
    Each of these suggestions is a desirable ventilation practice which 
MSHA supports. However, the final rule is not intended to set detailed 
standards for the installation of ventilation control devices. Instead, 
the rule addresses minimum requirements for face air quantities and 
requires the face ventilation system used to deliver these quantities 
to be maintained.
    Some commenters indicated a concern about so-called ``deep-cut'' 
mining wherein continuous miners, by remote control, develop cuts from 
25 to 60 feet inby permanent roof support. Commenters questioned the 
adequacy of face ventilation where ventilation controls may be 30 to 50 
feet from the face. Specifically, questions were raised about: whether 
adequate ventilation actually reaches the face in ``deep cuts'' to 
dilute methane; whether more frequent air measurements are needed; 
whether methane checks are representative of face concentrations; 
maximum feasible cut depth and ventilation device distance; respirable 
dust in ``deep cuts;'' proper maintenance of ventilation control 
devices; how ventilation is maintained after the continuous miner is 
withdrawn from the cut; roof bolter ventilation; and differences 
between scrubber systems and sprayfan systems. Another commenter noted 
that historically most roof fall fatalities have occurred within 25 
feet of the face. This commenter asserted that the deep-cut mining 
system helps to resolve this problem and reduce exposure. The commenter 
continues that to prohibit any variation from the 10 foot line curtain 
distance requirement would adversely affect safety of the miners 
working in the area.
    MSHA agrees that each of these issues is important. The appropriate 
vehicle to address these specific concerns is the mine ventilation plan 
required by existing Sec. 75.370. The mine ventilation plan provides 
the necessary latitude to address the diversity of mining conditions 
found throughout the country. Details of each system must be shown in 
the plan and must be specific to the conditions at each mine where such 
a system is employed. Also, MSHA's review and approval of mine plans 
includes an onsite investigation to evaluate the system and to assess 
the adequacy of the specified plan parameters. In addition, inspectors 
routinely evaluate the suitability of the mine ventilation plan during 
regular mine inspections.
    The commenter's concerns about methane checks in ``deep cuts'' is 
addressed by the final rule Sec. 75.362(d)(2) which requires that 
methane tests be made ``at the face.'' This new requirement will assure 
that measurements are taken at the location where the hazard is most 
likely to occur. Testimony received at the public rulemaking hearings 
indicated that technology exists in the form of extendable probes that 
can be used to take these measurements, without putting miners at 
additional risk from fall of ground.

Section 75.332 Working Sections and Working Places

    Working sections and working places are the areas of a coal mine 
with the greatest amount of activity and the largest concentration of 
workers. They are the location of the greatest number of potential 
ignition sources. They therefore harbor the greatest risk of accidents 
such as methane ignitions and explosions and equipment fires. Section 
75.332 addresses the ways these areas are ventilated to reduce the 
likelihood of an accident on one section impacting another section, 
with deadly consequences. Generally, Sec. 75.332 provides that each of 
these areas must be ventilated with a separate split of fresh air that 
has not been used to ventilate another working area or an area where 
mining has ceased if this area cannot be examined. When ventilated in 
this manner, the products from a fire on one section will not 
contaminate another section and methane in worked-out areas will not be 
carried to working sections by the ventilating air stream.
    The final rule provides that each working section and each area 
where mechanized mining equipment is being installed or removed, shall 
be ventilated by a separate split of intake air directed by overcasts, 
undercasts or other permanent ventilation controls. The final rule 
adopts the language of proposed Sec. 75.332(a)(1), which is identical 
to existing Sec. 75.332(a)(1). An in-depth discussion of the reproposal 
of provisions concerning the installation and removal of mechanized 
mining equipment is presented in the General Discussion section of this 
preamble.
    Several commenters responded to Sec. 75.332(a)(1). Some commenters 
suggested that the standard be revised to permit the installation of 
mechanized mining equipment in either the return or intake air courses 
of working sections provided the air had not been used to ventilate any 
worked-out areas, areas where pillars have been recovered, or bleeder 
systems. The commenters maintained that prohibiting the installation of 
longwall equipment on the same split of air as a developing unit delays 
the installation of a mining system. The commenters further observed 
that this mining equipment consists mainly of steel conveyor sections 
and roof supports that contain a 95 percent water-based hydraulic fluid 
which does not burn. Therefore, according to these commenters, longwall 
mining equipment can safely be installed on the intake side of an 
active mining unit and, with monitoring, in the return air course of an 
active mining unit.
    The safety benefits of using separate splits of air to provide 
ventilation are well established. A primary benefit of such a provision 
is to protect workers down-wind from being put at risk by events up-
wind from their location. Among the most serious of these risks is 
miners being overcome by the products of combustion or an explosion.
    In Miner's Circular 50, ``Explosions and Fires in Bituminous-Coal 
Mines'' published by the Bureau of Mines in 

[[Page 9782]]
1954, the authors state that when air travels a long path through a 
mine, it gradually becomes depleted of oxygen and may become so 
contaminated with other gases that it no longer is healthful, or it may 
accumulate enough explosive gas to present an explosion hazard. The 
authors go on to state that when the air is divided into several 
splits, each traveling a short path, better air can be furnished to 
each group of persons in the mine. Further, if a local explosion or 
fire should occur, the poisonous gases evolved may be confined to one 
section and the force of the explosion and the gases may kill all the 
persons in that particular section but may not affect other sections of 
the mine. According to the authors, when a mine is ventilated by a 
continuous current of air, the miners on the return side of an 
explosion or fire probably will be killed or overcome by the poisonous 
gases and that judicious splitting of the air is a safeguard against 
this eventuality.
    Similarly, Stefanko states in the 1973 edition of the Society of 
Mining Engineers (SME) Engineering Handbook that splitting the air is 
recognized as being necessary for safety and presents only minimal 
power cost.
    The commenters implied that because longwall mining equipment is 
largely noncombustible, this danger is minimized for workers down-wind 
on an active mining section. This reasoning overlooks the fact, 
however, that the installation of a longwall is labor-intensive, 
involving cutting and welding in the presence of methane and coal, as 
well as machinery operating under load. These conditions add 
contaminants to the ventilating current, and increase the possibility 
of a fire or explosion. Likewise, a longwall being installed on the 
return side of an active mining section would expose the miners doing 
the installation to the dust and gases, and the results of a fire or 
explosion, from the section. Even with monitoring, miners would be put 
at risk as their opportunities for escape would be limited. For these 
reasons, the final rule does not adopt the commenters'' suggestion.
    One commenter also suggested that ``approved ventilation controls'' 
be required instead of specifying that overcasts, undercasts or other 
permanent ventilation controls be used to direct intake air. The 
commenter explained that this would allow operators the flexibility of 
submitting plans that allow the use of temporary controls in some 
instances.
    Temporary controls to split air are not as reliable as permanent 
controls. The first explosion at the Scotia Mine in 1976 which killed 
15 miners, was due in part to the improper use of a temporary 
ventilation control where a permanent control (i.e., an overcast) 
should have been used. More recently, the explosion that occurred 
during the set up of a longwall at the Golden Eagle Mine in 1991 which 
injured 11 miners involved the removal of two permanent ventilation 
controls and the replacement of these controls with temporary controls. 
As these and other accidents illustrate, the ventilation controls that 
deliver air to working areas are vitally important to miners'' safety. 
Therefore, the final rule requires that these controls be permanent in 
nature and not temporary.
    Another commenter indicated that the use of temporary controls 
would lower worker exposure to hazards by not requiring repeated 
handling of permanent control materials which can be heavy. Proper 
handling practices and modern materials can reduce the risk of injuries 
associated with handling construction materials. MSHA considers these 
risks lower than the dangers of using temporary controls in lieu of 
permanent controls.

Section 75.333 Ventilation Controls

    The primary means for directing air from the outside, through the 
mine openings, to the working areas and back to the surface is through 
the use of ventilation controls: either permanent controls, such as 
stoppings (walls), overcasts or undercasts (air bridges), and doors, or 
temporary controls, such as line brattice (curtains). Permanent 
ventilation controls are designed for long term use while temporary 
controls are intended for use on a short term basis. In general, 
Sec. 75.333 specifies where each type of control can be used and how 
each permanent control is to be constructed. It is essential that 
ventilation controls be correctly constructed, maintained, and properly 
located to provide ventilation to working sections and other areas 
where it is needed to dilute methane, respirable coal mine dust and 
other contaminants, and provide miners with a safe and healthful work 
environment.
    The final rule revises paragraphs (a), (b)(1), (b)(3), (b)(4) and 
(e)(1) of existing Sec. 75.333, and adds a new paragraph (h). Revisions 
to paragraphs (a) and (e)(1) address the durability of stoppings, while 
the revisions to (b)(1), (b)(3) and (b)(4) address ventilation controls 
required when continuous haulage systems are used. New paragraph (h) 
requires all permanent ventilation controls, including seals, to be 
maintained to serve the purpose for which they were built.
    The use of continuous haulage systems, particularly in low seam 
coal mines, is becoming more common. The final rule specifically 
addresses continuous haulage systems in paragraphs (b)(1), (b)(3) and 
(b)(4) of the rule and clarifies where temporary controls are an 
acceptable means of ventilation control when these systems are used. 
Continuous haulage systems utilize mobile bridge conveyors or similar 
mechanisms to transport coal directly from a continuous mining machine 
to a low profile belt. As the continuous mining machine moves from 
place to place, the continuous haulage system slides back and forth 
along a low profile conveyor belt using a ``dolly'' or other travel 
mechanism. The low profile conveyor belt then transports the coal to 
the section conveyor belt.
    The existing rule permits the use of temporary ventilation controls 
in lieu of permanent ventilation controls to separate continuous face 
haulage systems from return, intake, and primary escapeway entries in 
rooms developed 600 feet or less from the centerline of the entry from 
which the rooms were developed. This practice is consistent with 
longstanding MSHA policy, which recognizes that these rooms are used 
for a short duration and the minimum air quantity must be maintained 
regardless of the controls used.
    Existing paragraph (b)(1) allows temporary controls to separate 
intake and return air courses in rooms driven 600 feet or less from the 
centerline of the entry from which the room was developed. The final 
rule adds to existing paragraph (b)(1) the proposed language clarifying 
that the use of temporary controls in these rooms is also acceptable 
when continuous haulage systems are used. This change responds to 
commenters who point out that the rooms in which the continuous haulage 
systems are installed are continuously attended by the operators of the 
system and an immediate response to any safety related problem with the 
system or the ventilation controls would be expected. Commenters also 
noted that two or three rooms are often concurrently developed using a 
continuous haulage system and the life of the actively developing rooms 
is often less than three days. As a result of this short life, mining 
in these rooms is often completed before construction of permanent 
controls is finished. Also, access to the continuous haulage system is 
required through crosscuts for maintenance and operation of the system.
    Under paragraphs (b)(3) and (b)(4) the proposal would have required 
belt and 

[[Page 9783]]
intake separation to the outby travel point of the dolly and belt and 
primary escapeway separation to the inby most travel point. Commenters 
indicated confusion because of the distinction between intake and 
primary escapeway separation and believed that conflicts would exist. 
Commenters also suggested that the language proposed to address the use 
of temporary ventilation controls for continuous haulage systems was 
confusing and contradictory. The final rule revises the requirements of 
proposed paragraphs (b)(3) and (b)(4) to respond to these comments.
    Paragraph (b)(3) of the final rule retains the requirement that 
permanent controls be provided to separate belt conveyor haulageways 
from intake air courses when the air in the intake air course is used 
to provide air to active working places. The final rule also retains 
the proposed provision that when continuous haulage systems are used in 
rooms less than 600 feet from the centerline of the entry from which 
the rooms were developed, temporary stoppings or other temporary 
ventilation controls may be built and maintained to provide the 
required separation.
    Commenters stated that new technology may result in continuous 
haulage systems with the outby point of travel of the dolly extending 
considerably beyond the 600 feet distance. The commenters noted that 
such an extended length of temporary controls could result in 
unanticipated adverse consequences for the ventilation system, and 
suggested that a maximum distance of 300 feet outby the inby point of 
travel of the dolly be established for the use of temporary ventilation 
controls. MSHA agrees that extensive use of temporary ventilation 
controls can create problems, including excessive leakage and the 
possible short circuiting of air. The final rule, therefore, limits the 
distance that temporary controls may be used to separate continuous 
haulage systems from intake air courses, including the primary 
escapeway. The final rule permits temporary controls to be used from 
the point of deepest penetration of the conveyor belt entry to the most 
outby point of travel of the dolly or 600 feet, whichever distance is 
the less. As a result, 600 feet is the maximum linear distance of entry 
in which temporary controls may be used for separation of air courses. 
The 600 feet would be measured as a straight-line distance from the 
point of deepest penetration in the conveyor belt haulage entry. This 
approach comports with the 600 foot limit for the use of temporary 
stoppings in rooms and allows a reasonable use of temporary ventilation 
controls with continuous haulage systems, while preserving the 
integrity of the ventilation system. At present, MSHA would expect that 
the most outby point of travel of the dolly would govern since MSHA is 
not aware of any continuous haulage systems which travel more than 600 
feet outby the point of deepest penetration.
    Paragraph (b)(4) of the final rule continues to require permanent 
stoppings or other permanent ventilation control devices to separate 
the primary escapeway from the belt and trolley haulage entries, as 
required by Sec. 75.380(g). Commenters suggested that for the purposes 
of Sec. 75.380(g), the definition of loading point in proposed 
paragraph (b)(4) be revised to be the outby point of travel of the 
dolly as opposed to the inby point of travel. The final rule adopts 
this suggestion and requires separation by permanent stoppings to be 
maintained to the outby point of travel of the dolly or 600 feet from 
the point of deepest penetration, whichever distance is less, to 
separate the haulage entry from the primary escapeway. The provisions 
of Sec. 75.380(g) continue to allow the district manager to require a 
greater or lesser distance for this separation.
    In response to questions about acceptable construction methods and 
materials for permanent ventilation controls (excluding seals) MSHA 
proposed eliminating the definition of ``durable'' in paragraph (a) and 
to modify paragraph (e)(1). The proposal would have required these 
controls to be constructed in a manner and of materials that result in 
a construction that has been tested and shown to have a minimum 
strength of 39 pounds per square foot as tested under ASTM E72-80 
Section 12--Transverse Load-Specimen Vertical, load only (ASTM E72-80). 
The 8-inch hollow-core concrete block stopping with mortared joints, to 
which all other constructions were tied under the definition of durable 
in the existing standard, has been tested and shown to have a minimum 
strength of 39 pounds per square foot.
    MSHA received numerous comments questioning the validity of the 
ASTM E72-80 test for determining acceptability of underground 
ventilation controls. Commenters questioned the appropriateness of a 
strength requirement of 39 pounds per square foot and the relevance of 
this value to the in-mine conditions. After review, MSHA continues to 
believe that use of the ASTM E72-80 test to determine that the relative 
strength of a ventilation control construction is appropriate and the 
final rule retains this standard. However, MSHA sees merit in some of 
the suggestions made by commenters. Commenters suggested that some 
constructions can not be tested according to the ASTM test, some 
constructions that are widely used in coal mines do not meet the 39 
pound per square foot threshold, and the ASTM test can only be run at a 
limited number of locations nationwide.
    After reviewing all of the comments received and based on 
experience with various construction methods and materials used for 
permanent ventilation controls since the inception of the Mine Act, the 
final rule recognizes traditionally accepted construction methods for 
permanent ventilation controls, and retains the ASTM test for new 
materials and methods. Controls made with new materials or methods must 
be comparable in strength to controls made with traditionally accepted 
materials or methods.
    Since the inception of the Mine Act, a number of traditionally 
accepted construction methods have performed adequately and have served 
their intended function of separating air courses. These traditionally 
accepted construction methods are: 8-inch and 6-inch concrete blocks 
(both hollow-core and solid) with mortared joints; 8-inch and 6-inch 
concrete blocks dry-stacked and coated on both sides with a strength 
enhancing sealant suitable for dry-stacked stoppings; 8-inch and 6-inch 
concrete blocks dry-stacked and coated on the high pressure side with a 
strength enhancing sealant suitable for dry-stacked stoppings; steel 
stoppings (minimum 20-gauge) with seams sealed using manufacturer's 
recommended tape and with the tape and perimeter of the metal stopping 
coated with a suitable mine sealant; and lightweight incombustible 
cementatious masonry blocks coated on the joints and perimeter with a 
strength enhancing sealant suitable for dry-stacked stoppings. In 
addition, 4-inch concrete blocks may be used in the above applications 
in seam heights less than 48 inches. Tongue and groove 4-inch concrete 
blocks coated on both sides with a strength enhancing sealant suitable 
for dry-stacked stoppings may be used in coal seams of any height. The 
sealants referred to in this paragraph would be applied in the 
thickness recommended by the manufacturer. MSHA maintains a list of 
sealants which may be used for the above applications. This list is 
available at each MSHA District Office. The final rule would continue 
to permit these traditionally accepted construction 

[[Page 9784]]
methods to be acceptable for the construction of ventilation controls.
    For new construction methods or materials other than those used for 
the traditionally accepted constructions identified above, the final 
rule requires that the strength be equal to or greater than the 
traditionally accepted in-mine controls. Tests may be performed under 
ASTM E72-80 Section 12--Transverse Load-Specimen Vertical, load only, 
or the operator may conduct comparative in-mine tests. In-mine tests 
must be designed to demonstrate the comparative strength of the 
proposed construction and a traditionally accepted in-mine control.
    As with the existing rule, the final rule would require, in 
paragraph (e)(1)(ii), that all overcasts, undercasts, shaft partitions, 
permanent stoppings, and regulators, installed after November 15, 1992, 
be constructed of noncombustible material. Also, like the existing 
standard, the final rule lists materials that would be suitable for 
these controls. The final rule would also continue to prohibit 
ventilation controls installed after November 15, 1992, from being 
constructed of aluminum.
    Paragraph (h) of the proposal would have required that all 
permanent ventilation controls, including seals, be maintained to serve 
the purpose for which they were built. The final rule retains proposed 
paragraph (h) with one revision. One commenter stated that the 
paragraph should require all ventilation controls, including temporary 
controls, to be maintained to serve the purpose for which they were 
built. Given the importance of temporary controls devices in providing 
for adequate ventilation, the final rule requires all ventilation 
controls, both permanent and temporary, including all doors and seals, 
to be maintained to serve the purpose for which they were built. This 
standard applies to all ventilation controls, regardless of the 
construction date.
    Relative to seal maintenance, MSHA does not intend that the 
maintenance requirement be applied to seals located within another 
sealed area. Additionally, the rule does not apply to seals which have 
become consumed within a gob area which is ventilated and evaluated in 
a manner approved in the mine ventilation plan.
    One commenter raised several questions concerning what MSHA would 
consider to be an acceptable temporary stopping. MSHA has not defined 
the term ``temporary ventilation control'' in the rule. The commenter 
stated that, in the preamble to the proposal, MSHA refers to ``properly 
constructed'' temporary stoppings but does not include a standard for 
construction or installation and maintenance of temporary stoppings. 
The commenter adds that temporary ventilation controls are a source of 
potential leakage and are often susceptible to damage from roof and rib 
falls and from mobile equipment. The commenter also refers to several 
accidents where failure to maintain permanent or temporary ventilation 
controls was a critical factor in the accident.
    MSHA agrees that to properly direct the flow of air and provide for 
adequate face ventilation, temporary controls, as well as all permanent 
ventilation controls, must be installed and maintained in an adequate 
manner to control leakage. MSHA has accepted as temporary controls, 
check curtains or other flame- resistant material approved by MSHA that 
are constructed and installed in such a manner to minimize leakage. As 
required by paragraph (h) of this section of the final rule, these 
controls must be maintained to serve the purpose for which they were 
built.

Section 75.334 Worked-Out Areas and Areas Where Pillars Are Being Recovered

    Worked-out areas, areas where coal extraction has been completed, 
can pose deadly hazards to miners, including an explosive methane 
accumulation, irrespirable atmosphere, and the possibility of fire from 
spontaneous combustion. Section 75.334 establishes the requirements for 
ventilation of these areas to mitigate these hazards. In general, 
Sec. 75.334 requires that following mining, these areas are to be 
sealed or ventilated. Section 75.334 also specifies the requirements 
for evaluating the effectiveness of the ventilation of worked-out areas 
so operators can determine that the ventilation system is functioning 
as intended.
    The final rule revises paragraph (e) of the existing Sec. 75.334. 
Existing paragraph (e) requires that each mining system be designed so 
that worked-out areas can be sealed. The final rule adds to paragraph 
(e) the proposed requirement that the location and sequence of 
construction of proposed seals be specified in the approved mine 
ventilation plan. Improper location and sequencing of seal construction 
can have a dangerous effect on mine air quality and ventilation. As the 
proper location and sequence of construction of seals is a mine-by-mine 
determination, the mine ventilation plan provides the most workable 
mechanism by which to assure proper air quality and ventilation of the 
mine.
    Several commenters objected to including seal construction sequence 
as part of the information to be submitted for approval in the mine 
ventilation plan. Their rationale was that mining conditions change and 
could result in a change in the sequence of seal construction. The 
construction might then be delayed while approval for the change is 
obtained. These commenters suggested that in some cases, delays in seal 
construction could result in a hazard to miners. Other commenters 
stated that the sequence of construction of seals is more appropriately 
and more easily shown on the mine ventilation map required by 
Sec. 75.372. Another commenter stated that the sequence of construction 
should be subject to approval because the placement of seals if 
improperly installed can cause adverse effects on the ventilation 
system and gob gases. MSHA is sensitive to the concern that a delay in 
approval could result in a hazard to miners and, as explained in the 
preamble discussion of Sec. 75.370, if a delay in seal construction 
would result in a hazard to miners the review and approval of the plan 
can be expedited.
    MSHA agrees with the commenter that the location and sequence of 
seal construction may be more easily, that is, more clearly shown on 
the mine map required by Sec. 75.372 than in the written text of the 
plan submitted under Sec. 75.371. The existing standard permits 
appropriate information required under Sec. 75.371 to be shown on the 
map required by Sec. 75.372. The effect is that the information both 
appears on the ventilation map and in the ventilation plan and is 
subject to approval. The discussion of Sec. 75.371(bb) further 
addresses this point.
    Spontaneous combustion is the process through which coal or other 
materials self heat by the absorption of oxygen. Paragraph (f) of 
Sec. 75.334 addresses mines with a demonstrated history of spontaneous 
combustion and those located in coal seams determined to be susceptible 
to spontaneous combustion. Paragraph (f) requires that the approved 
mine ventilation plan for these mines specify the measures that will be 
used to detect methane, carbon monoxide, and oxygen concentrations 
during and after pillar recovery, and in worked-out areas where no 
pillars have been recovered; the actions that will be taken to protect 
miners from the hazards of spontaneous combustion; and, if a bleeder 
system will not be used, the methods that will be used to control 
spontaneous combustion, accumulations of methane-air mixtures, and 
other gases, dusts, and fumes in the worked-out area. 

[[Page 9785]]

    Through meetings with various segments of the mining community, 
MSHA became aware of a concern that paragraph (f) of existing 
Sec. 75.334 may have been promulgated without the public being provided 
the opportunity to adequately comment. Although MSHA believes that 
existing paragraph (f) was promulgated properly, the Agency reproposed 
paragraph (f) with wording identical to that used in existing 
Sec. 75.334. The purpose of the reproposal was to assure MSHA received 
and considered all pertinent comments.
    Several commenters to the existing rule suggested that bleeder 
systems should not be required for all mines. These commenters stated 
that in some mines the practice of ventilating worked-out areas 
increases the risk of spontaneous combustion by supplying oxygen to 
combustion-prone materials in these areas. They also requested that the 
final rule promulgated in 1992 include provisions to address 
spontaneous combustion. MSHA acknowledged the need to reduce the flow 
of oxygen to areas where there is a likelihood of spontaneous 
combustion, and included in the 1992 rule requirements for mine 
ventilation plans to address spontaneous combustion in mines with a 
demonstrated history of this hazard or mines that are located in coal 
seams determined to be susceptible to spontaneous combustion.
    Experience gained through application of the existing standard has 
demonstrated that a limited number of mines have experienced 
spontaneous combustion problems. Studies by the Bureau of Mines have 
identified the volatile properties of coal seams and have determined 
that certain seams are susceptible to spontaneous combustion. The final 
rule is directed to mines in these seams.
    MSHA is not suggesting that all coal mines will meet the test to 
show susceptibility to spontaneous combustion. A demonstrated history 
or the determination of susceptibility to spontaneous combustion is a 
prerequisite to the applicability of paragraph (f). While it is true 
that all coal oxidizes when exposed to air, this fact is not sufficient 
to make the determination that a coal seam is susceptible to 
spontaneous combustion. MSHA would expect that absent a demonstrated 
history of spontaneous combustion in a mine, an operator would provide 
the necessary data to demonstrate that the mine is susceptible to 
spontaneous combustion so that the provisions of paragraph (f) should 
apply. A number of methods are used to determine the self heating 
tendency of a coal.
    However, MSHA is also mindful that some mines that have a 
spontaneous combustion problem may be unable to reduce the oxygen 
content to a sufficiently low level to mitigate spontaneous combustion. 
For these mines, a bleederless system may not be appropriate. To 
illustrate, it is well known that the oxygen level in a gob varies 
depending on the location where the measurement is made. For example, 
the periphery of a gob normally will have higher oxygen levels than the 
interior of the gob. The oxygen level in the interior of the gob is 
critical when dealing with spontaneous combustion. If conditions are 
such that the oxygen content in critical areas within a gob cannot be 
reduced below that necessary for a methane ignition to occur, a bleeder 
system may provide the most safety. MSHA specifically solicited comment 
on this subject; however, none was received.
    Under paragraph (f)(1), the approved ventilation plans for mines 
that have or are susceptible to spontaneous combustion must specify 
measures to detect methane, carbon monoxide, and oxygen concentrations 
in worked-out areas. These measures must be taken during and after 
pillar recovery and in worked-out areas where no pillars have been 
recovered. The purpose of these measures is to determine if worked-out 
areas will be ventilated or sealed. If the methane concentration or 
other hazards in the worked-out area cannot be controlled while the 
mine is limiting airflow to avoid spontaneous combustion, it may be 
necessary to seal or to ventilate the worked-out area using a bleeder 
system. These measures also help to determine the extent to which the 
worked-out areas can be ventilated without increasing the spontaneous 
combustion hazard.
    Under the provisions of paragraph (f)(2) the operator is required 
to specify in the mine ventilation plan the actions that will be taken 
to protect miners from the hazards of spontaneous combustion. 
Protections from the hazards of spontaneous combustion might include: 
Additional continuous monitoring of fire gases at strategic locations 
underground, increased air sample collection and analysis, trending of 
air contaminant data, increased examinations, and changes to the mine 
ventilation system such as redistribution of air or pressure balancing. 
This requirement would be triggered if the mine has a demonstrated 
history of spontaneous combustion, or, if an evaluation of the 
susceptibility of the coal seam to spontaneous combustion leads to a 
mine operator determination that a bleeder system should not be used.
    One commenter stated that this rule is unnecessary because only a 
limited number of mines actually have a demonstrated spontaneous 
combustion problem. The commenter suggested that the petition for 
modification (variance) process should be used to address this issue, 
which would allow miners representatives to participate. The final rule 
does not adopt this approach. To the extent practicable, an objective 
of this rulemaking is to reduce the need for exceptions and paperwork. 
In this case, the existing mine ventilation plan process provides a 
ready-made mechanism for establishing the precautions necessary, on a 
mine-by-mine basis, to protect miners from the hazards of spontaneous 
combustion in a timely manner. In addition, under the final rule, 
miners representatives are afforded input into the mine ventilation 
plan.
    Another commenter stated that paragraph (f) should be directed more 
to the detection and control of spontaneous combustion and not solely 
at its prevention. The commenter offered examples of detection and 
control techniques that could be used.
    MSHA agrees that spontaneous combustion prevention, detection and 
control are all important when dealing with spontaneous combustion. The 
final rule recognizes, however, that while prevention is the goal, 
instances of spontaneous combustion will occur.
    Another commenter stated that the preamble to the proposal was not 
correct in that it implied a need to limit airflow to avoid spontaneous 
combustion. The commenter states that, to avoid spontaneous combustion, 
miners must create a near-zero pressure differential across most areas 
of concern. MSHA agrees that creating a ``near-zero pressure 
differential'' will have the desired effect of limiting the airflow. In 
a paper entitled ``Examination of Bleederless Ventilation Practices for 
Spontaneous Combustion Control in U. S. Coal Mines'' presented at the 
7th U.S. Mine Ventilation Symposium in June 1995, the authors report 
that their study revealed that restricting airflow into mined-out areas 
is recognized world-wide as a spontaneous combustion control measure 
and that when designing a bleederless ventilation system critical 
attention must be given to mine layout, seal construction, methane 
drainage, regulations, monitoring, and emergency procedures. In 
discussing the subject of air leakage, Koenning in a paper entitled 
``Spontaneous Combustion in Coal 

[[Page 9786]]
Mines'' presented at the 4th U.S. Mine Ventilation Symposium in June 
1989, identified air leakage as the most often cited cause of 
spontaneous combustion. In both of these papers, the authors emphasize 
the need to properly design a bleederless ventilation system to reduce 
the likelihood of spontaneous combustion and achieve the level of 
worker safety desired. MSHA agrees with these authors that a 
bleederless ventilation system must be designed to encompass all of the 
factors identified. It was suggested by one commenter that measurement 
of carbon dioxide should be included in the requirements of paragraph 
(f). In discussing the gases required to be measured (methane, oxygen, 
and carbon monoxide), the commenter stated that these gases alone will 
not aid in the detection of spontaneous combustion in its incipient or 
developed stage. The commenter suggested that miners be required to 
monitor for carbon dioxide because, in the opinion of the commenter, 
the trend in the ratio CO/CO<INF>2 is the only viable predictor.
    MSHA sees merit in the measurement of carbon dioxide as well as 
other products of combustion to assist in the detection of spontaneous 
combustion. However, the ratio CO/CO<INF>2 is not the only viable 
predictor of spontaneous combustion. One researcher suggested that 
carbon monoxide production is the earliest, detectable effect of 
spontaneous heating. Others have suggested, following a series of 
tests, that four gas ratios clearly indicated the development of 
thermal runaway, but only the CO<INF>2- <triangle>O<INF>2 ratio gave
an 
early warning of the heating in the coalbed.
    As can be seen, a number of methods of predicting the onset of 
spontaneous combustion have been suggested. While paragraph (f)(1) 
requires only the measurement of methane, oxygen, and carbon monoxide, 
MSHA would not discourage operators from incorporating, as part of the 
mine ventilation plan, any or all of these methods as well as other 
appropriate methods to aid in the early detection of spontaneous 
combustion.

Section 75.340 Underground Electrical Installations

    Electrical installations can provide an ignition source for methane 
and can represent a serious fire hazard underground. Typical electrical 
installations are battery charging stations, substations, rectifiers 
and certain water pumps. Section 75.340 requires that these 
installations be ventilated and protected against fire. These 
installations must also be housed in noncombustible structures or areas 
or protected with fire suppressions systems, and be ventilated or 
monitored to protect miners working down stream from the products of 
combustion.
    MSHA proposed to revise paragraph (a) of existing Sec. 75.340 to 
clarify the standard and to add requirements concerning alarms and 
sensors. The final rule adopts the language in the proposal with one 
modification. It replaces the word ``located'' with the word 
``housed.''
    Existing 75.340(a) requires that certain underground electrical 
equipment be either located in a noncombustible structure or area or 
equipped with a fire suppression system. Section 75.340 (a) also 
requires that the equipment be ventilated by intake air, and lists 
alternatives ways to do so in paragraphs (a)(1),(a)(2), and (a)(3). The 
final rule adds language to paragraph (a)(3), the alternative which 
establishes an acceptable means for monitoring the underground 
electrical installations using sensors other than a Sec. 75.351 
atmospheric monitoring system.
    MSHA sought in the proposal to clarify the application of existing 
Sec. 75.340(a)(3). Paragraph (a)(3) of the existing rule provides for 
the activation of doors upon the presence of certain indications of a 
possible fire. The paragraph was appropriate for enclosed structures or 
areas; but questions at informational meetings challenged its 
applicability to the alternative where a fire suppression system was 
used without an enclosure. To address the questions, the proposal 
placed the requirements for noncombustible structures or areas and for 
fire suppression systems into separate paragraphs. MSHA proposed that 
one of the alternatives for ventilating with intake air (monitoring the 
underground electrical installations using sensors other than a 
Sec. 75.351 atmospheric monitoring system) was acceptable only if the 
equipment was located in a noncombustible structure or area and not 
acceptable if only a fire suppression system was used. This revision 
eliminates the confusion that existed with the existing rule. It should 
be noted that if an operator elects to locate this equipment in a 
noncombustible structure or area, the operator would not be precluded 
from also installing a fire suppression system.
    One commenter questioned the reason for separating fire suppression 
and noncombustible structures, noting that there was no need for the 
distinction in the rule. In objecting to the proposal, the commenter 
stated that there should be several cumulative layers of protection, 
including both fireproof enclosures and fire suppression systems. The 
commenter includes several examples of fires involving compressors to 
illustrate this point. MSHA has addressed concerns relative to 
compressor fires in the final rule section dealing with compressors, 
Sec. 75.344. Other examples cited by the commenter included explosions 
caused by mobile equipment and a fire that occurred on a power center 
located at the working section. The instances cited by the commenter 
are not relevant to Sec. 75.340. The commenter argued that fire 
suppression systems have not worked and uses the compressor fires 
previously mentioned to illustrate the point. MSHA notes that there are 
numerous instances where the systems have worked. However, in the vast 
majority of these cases there is no documentation because there is no 
requirement for reporting fires that are extinguished within 30 
minutes.
    The final rule in paragraph (a)(1)(iii) revises existing paragraph 
(a)(3) of Sec. 75.340 by adding 2 requirements. It adds a requirement 
that a visual and audible alarm be provided on installations if the 
(a)(1)(iii) alternative is selected. Also, when operating under this 
alternative, monitoring of intake air that ventilates battery charging 
stations must be done with sensors not affected by hydrogen.
    Some commenters noted their agreement with these proposed changes. 
Noting that no single system is failsafe, one commenter suggested that 
all the requirements of Sec. 75.340 be combined and made applicable in 
all cases. The requirements would include; noncombustible structures, 
fire suppression, ventilation directly to the return, additional 
communications, continuous AMS monitoring for carbon monoxide, methane, 
and hydrogen, along with automatic closing doors and temperature 
protection. After consideration of the comments and the underlying 
rationale, MSHA concludes that to require that the alternatives be 
applied cumulatively in every case would be infeasible or impractical. 
In addition, MSHA does not believe that these overly restrictive 
requirements are necessary in all circumstances.
    Paragraph (a)(1)(iii) addresses electrical installations that are 
equipped with doors that automatically close when sensor readings reach 
certain levels. One of these action levels is a level for the optical 
density of smoke. In Sec. 75.340 (a)(1)(iii)(B) of the proposal and the 
preamble discussion on page 26371, MSHA refers to the optical density 
of smoke of 0.05 per meter to characterize the sensitivity of smoke 
detectors. As discussed in MSHA's opening statement to the ventilation 
rulemaking hearings, 

[[Page 9787]]
the value used for the optical density of smoke is based on information 
provided from the Bureau of Mines. MSHA pointed out that based on 
comments received from the Bureau of Mines, this number is incorrect 
and should be divided by 2.303 to conform to the internationally 
accepted term of optical density. No commenter took issue with this 
point. MSHA has made the correction in the final rule. One commenter 
suggested that optical densities be increased and based on an ambient 
to account for background dust. In contrast, another commenter 
suggested that the specified optical density should be reduced by half. 
MSHA has found insufficient justification to adopt either of these 
suggestions and believes that the specified 0.05, corrected to 0.022 
based on comments from the Bureau of Mines, is the appropriate level 
for optical density used in Sec. 75.340. Existing Sec. 75.351 
Atmospheric monitoring system (AMS), uses a level for optical density 
of smoke of 0.05 per meter. MSHA recognizes that the level in 
Sec. 75.351 should also be corrected. MSHA intends to correct the level 
for optical density used in Sec. 75.351 in a future rulemaking. In the 
meantime, MSHA will use an optical density of 0.022 per meter for 
purposes of Sec. 75.340.
    The visual and audible alarm required in paragraph (a)(1)(iii) must 
be situated so that it can be seen or heard by persons traveling in the 
intake entry immediately adjacent to the installation. It was suggested 
to MSHA that these electrical installations may be susceptible to fire 
and the fire could go undetected. The visual and audible alarms would 
provide additional safety at these installations by alerting miners in 
the area.
    One commenter suggested that an alternative should be added to 
carbon monoxide or smoke detection. The suggested alternative would be 
to permit another means that would be approved by the district manager. 
This suggestion has not been adopted since both carbon monoxide 
monitoring and smoke detection have been shown to be effective and 
reliable and can be used.
    One commenter stated that battery chargers located on working 
sections do not present the same hazards as those located outby, along 
the intake. The commenter suggested that chargers located on working 
sections should be exempted from Sec. 75.340. MSHA disagrees. MSHA 
believes that battery chargers present the same safety hazards 
associated with other electrical equipment plus the charging of 
batteries results in the liberation of hydrogen. There is a 
demonstrated history of fires caused by battery chargers. The 
requirements are necessary to safely operate chargers, regardless of 
the location of the charger.
    One commenter suggested that all water pumps should be exempted 
from Sec. 75.340 because fire history is limited. The standard already 
exempts pumps that have limited fire hazard potential in paragraphs 
(b)(2) through (b)(6). Pumps outside of the listed categories do 
present hazards. As an example, a 200 horsepower pump exploded at a 
mine in Virginia after an extended period of being overheated. An 
example of a pump posing a limited hazard is an emulsion pump located 
at or near the section that is moved as the section advances or 
retreats. Emulsion pumps are considered for the purpose of Sec. 75.340 
to be water pumps.
    Also, one commenter called attention to MSHA's omission of the word 
``or'' in two places in Sec. 75.340, Underground Electrical 
Installations. MSHA agrees that the omission was inadvertent and so 
stated in its opening statement at the ventilation hearings. In 
Sec. 75.340, the word ``or'' has been inserted between paragraphs 
(a)(1) (i) and (ii) dealing with alternative ventilation requirements 
for noncombustible structures or areas and between paragraphs 
(a)(1)(iii) (A) and (B) setting out criteria that would govern the 
activation of automatic closing doors.
    Another commenter suggested that the signal from the visual and 
audible alarms required by existing paragraph (a)(3) should be sent to 
a surface location at the mine rather than being located outside the 
installation. The commenter supported the suggestion by indicating that 
a quicker response would thus be provided since the alarm would be 
immediately noticed. In order to achieve an effective level of safety, 
MSHA has provided in paragraph (a)(1)(iii) that the visual and audible 
alarm be located outside of and on the intake side of the enclosure. 
This location will permit persons traveling in the intake entry 
immediately adjacent to the installation to see or hear the alarm. 
Paragraph (a)(2) allows the use of an alternative system using an AMS 
which would provide an alarm at the surface of the mine.
    Finally, one commenter objected to the use of the word ``located'' 
in the phrase ``located in noncombustible structures or areas''. The 
commenter argued that MSHA should use the word ``housed'' and that the 
use of the word ``located'' actually reduces the protection intended by 
Congress. MSHA does not agree with that interpretation and maintains 
that in the context in which the word is used there is no meaningful 
distinction between the two words. However, because the word suggested 
by the commenter will not reduce safety and may add to the clarity of 
the rule for some readers, it has been adopted in the final rule.

Section 75.342 Methane Monitors

    Methane monitors are a critical link in the safety protections 
designed to prevent mine explosions. Mounted on mining equipment which 
works directly in the face, these instruments provide the first warning 
that gas is being liberated in potentially dangerous quantities. 
Methane monitors are relied upon to shut down mining equipment 
automatically when gas concentrations reach 2 percent. The continued 
operation of mining equipment under these conditions can lead to a 
spark and catastrophic explosion.
    The final rule revises paragraph (a)(4) which addresses maintenance 
and calibration of methane monitors that are required on underground 
mining equipment to provide a warning to equipment operators when the 
methane concentrations nears dangerous levels. Methane monitors also 
automatically deenergize the equipment when methane approaches the 
explosive range or if the monitor is not operating properly. The rule 
requires that trained persons perform maintenance and calibration of 
the methane monitors at least every 31 days and requires that 
calibration records be maintained. The final rule does not adopt the 
proposal which would have required that a written maintenance program 
be available for inspection.
    Some commenters expressed the view that the proposed revisions were 
unnecessary and recommended that they be deleted from the final rule. 
Other commenters supported the proposed revisions and urged MSHA to 
adopt additional requirements as well.
    Paragraph (a)(4) of the final rule requires that calibration and 
maintenance of the monitors be performed by persons properly trained in 
maintenance, calibration, and permissibility of the methane monitors. 
One commenter expressed the view that no change was needed to the 
existing rule. However, the rulemaking record also contains a number of 
examples in which poorly maintained or improperly repaired methane 
monitors have been found during the investigations of methane related 
accidents.
    The final rule in paragraph (a)(4)(ii) requires that each operator 
maintain a record of all calibration tests of methane monitors. As with 
other recordkeeping requirements under the final rule, records must be 
maintained in a secure 

[[Page 9788]]
book that is not susceptible to alteration, or may be kept 
electronically in a computer system so as to be secure and not 
susceptible to alteration. Some commenters recommended that a record be 
kept of all maintenance performed on a methane monitor, urging that a 
record is necessary to prove the maintenance is done. MSHA believes 
that the revisions contained in the final rule, together with the 
existing requirements, will assure an appropriate level of maintenance 
without the need for additional records of maintenance.
    Some commenters expressed concern over the security of computer-
based records, and offered examples of breaches of security in the 
banking and national security fields. Others, however, advocated the 
use of computers for the storage and retrieval of records as being 
highly accurate, requiring less storage space and facilitating data 
retrieval. MSHA agrees that security of required records is important. 
It is also MSHA's objective to make the final rule requirements for 
compilation and storage of records practical and in concert with modern 
methods. To this end, the final rule requires that the record of 
maintenance and calibration of methane monitors be maintained in secure 
books that are not susceptible to alteration, and also permits these 
records to be maintained electronically in a computer system so as to 
be secure and not susceptible to alteration. The calibration record 
will aid operators in tracking calibration activity and will serve as a 
check to assure that calibrations are being conducted at least once 
every 31 days. The record will also be reviewed by authorized 
representatives of the Secretary and miners' representatives to 
determine that calibrations are being conducted as required.
    Paragraph (a)(4)(iii) of the final rule requires that operators 
retain the record of calibration tests for 1 year from the date of the 
test. Records are to be maintained at a surface location at the mine 
and made available for inspection by authorized representatives of the 
Secretary and the representative of miners. A discussion of comments 
concerning the use of computers to maintain records can be found in the 
General Discussion of this preamble.
    Several commenters suggested that equipment not operated in the 
face area also be equipped with methane monitors. Commenters noted 
accidents which have occurred when this nonpermissible equipment has 
ignited methane in outby areas. Commenters also asserted that equipment 
used for the withdrawal of personnel during fan stoppages would be 
safer if methane monitors were provided. An opposing comment indicated 
that an expansion of the methane monitor coverage was not necessary 
since methane is rarely associated with outby areas. Because of the 
response time of methane monitors, and considering the speed at which 
most outby equipment normally operates, it is unlikely that a monitor 
would prevent a machine from entering a body of methane if such a 
concentration were encountered. MSHA believes that methane monitors are 
suitable and effective in face areas where coal is being cut, mined, or 
loaded. However, MSHA does not believe that an expansion of coverage to 
include all nonpermissible equipment is warranted.
    A number of commenters recommended that methane monitors should be 
calibrated at least every 7 days rather than at least every 31 days as 
provided by the existing standard. One commenter suggested daily 
calibration. Commenters noted that methane monitors lose sensitivity 
and that response time increases with monitor age and after exposures 
to elevated methane concentrations. The existing requirement for 
calibration of methane monitors at least every 31 days parallels the 
recommendations of several manufacturers. The 31 day requirement 
establishes a maximum time interval between calibrations. However, the 
final rule also requires the operator to maintain methane monitors in 
permissible and proper operating condition. Thus, under unusual 
circumstances of use, it is possible that weekly or even more frequent 
calibration may be necessary to comply with the standard.
    Comment was also received recommending an additional requirement 
that calibration records be countersigned by the Maintenance Supervisor 
or Chief Electrician at the mine. The final rule does not adopt this 
recommendation. The purpose of the calibration record required under 
the final rule is not the same as other records where countersigning is 
required by the final rule. Countersigning requirements are directed at 
informing upper mine management of hazardous conditions which require 
their attention. While the calibration record has the potential to 
assist mine management in identifying equipment problems, its main 
function is to assist operators in assuring that timely calibration is 
occurring.
    The proposal would have required that operators adopt a written 
maintenance program for methane monitors. Commenters pointed out that 
the existing standard already requires all permissible equipment, 
including methane monitors, to be maintained in permissible condition. 
MSHA agrees.

Section 75.344 Compressors

    Section 75.344 deals with the use of air compressors underground. 
As discussed in the introductory section of this preamble, MSHA stayed 
Sec. 75.344(a) because of a concern over a possible overheating or fire 
hazard. Improperly used or maintained air compressors can present a 
significant risk of fire underground. MSHA determined that the cause of 
the 1984 fire at the Wilberg Mine that claimed the lives of 27 miners 
was an improperly maintained compressor. In general, Sec. 75.344 
requires that most compressors be operated only while attended or 
located in a noncombustible structure or area that is monitored for 
temperature and carbon monoxide or smoke; have a fire suppression 
system; and, automatically shut down in the event of a fire.
    The final rule revises the existing Sec. 75.344, including the 
stayed paragraph (a), and supersedes interim Sec. 75.345. The final 
rule recognizes that in some cases compliance with the existing rule 
could result in heat buildup when a compressor is located in a 
noncombustible structure or area. To address this possible hazard the 
final rule provides an option. A compressor would be acceptable when 
not located in a noncombustible structure or area provided it is 
continuously attended by someone who can see the compressor at all 
times, activate the fire suppression system and shut off the 
compressor. Also, the existing rule is modified for compressors that 
are located in a noncombustible structure or area. They must be 
ventilated by intake air coursed directly into a return air course or 
to the surface and equipped with sensors to monitor for heat and for 
carbon monoxide or smoke. In addition, upon the activation of the fire 
suppression system, the compressor must automatically deenergize or 
shut off.
    The final rule does not include proposed paragraph (b)(2) which 
provided an additional alternative means of ventilating compressor 
installations located away from working sections and near a return air 
course where a substantial pressure differential exists.
    Comments were solicited on the exemption for compressors having a 
certain maximum horsepower. Comments were received both supporting and 
opposing a possible revision to increase the limit from 5 to 30 
horsepower. Because of the history of compressor fires, including the 
1984 Wilberg mine disaster which resulted in 

[[Page 9789]]
27 fatalities, the existing limitation of 5 horsepower has not been 
revised. One commenter questioned the proposal reference to 9 mine 
fires which started in compressors between 1970 and 1992. The commenter 
suggested that the nine fires was inaccurately low and referenced an 
MSHA report which stated that 21 compressor fires occurred between 1977 
and 1987. The preamble discussion addressing the number of fires was in 
relation to underground coal mines. Other compressor fires have 
occurred at surface coal mines and at noncoal mines. Regardless of the 
number of compressors affected, however, the safety concerns remain the 
same.
    Several commenters suggested that the cutoff for application of 
Sec. 75.344 be changed from 5 horsepower for all compressors to 30 
horsepower for reciprocating compressors and 5 horsepower for all other 
types of compressors. The rationale for this recommendation was that 
reciprocating compressors of up to 30 horsepower contain about the same 
amount of lubricating oil as 5 horsepower compressors. This suggestion 
was not included in the proposal, based on MSHA information (Report No. 
06-292-87 of the Industrial Safety Division, Pittsburgh Safety and 
Health Technology Center) that the predominant hazard for fire or 
explosion in reciprocating compressors is not the lubricating oil, but 
rather the formation of carbonaceous deposits in the discharge system. 
MSHA received comments addressing the formation of carbonaceous 
deposits in the discharge system indicating that the use of synthetic 
oil prevents any carbonaceous accumulation. Commenters suggested that 
all identified hazards would be eliminated through the use of synthetic 
oils. However, commenters also noted that synthetic oils have a higher 
flash point.
    MSHA has examined the subject of synthetic oils and found that 
synthetic oils can be formulated with polyalphaolefins, polyglycols, 
silicones, esters, phosphate-esters, and di-esters as the primary 
ingredient. These compounds are also blended with mineral oils to form 
synthetic lubricants. The rate of oxidation is varied among these 
compounds. Of these types, only silicone based lubricants exhibit 
virtually no oxidation and are used primarily where extremely high 
temperatures are expected. Also, silicone based lubricants are 
inherently fire resistant. Unfortunately, silicone based lubricants are 
incompatible with reciprocating compressors and will rapidly lead to 
failure of the compressor. Polyalphaolefins, polyglycols, and mineral 
oil blends all contain hydrocarbons and have a tendency to varnish and 
create deposits in air compressors. Accordingly, the final rule, like 
the existing rule, exempts compressors of five horsepower or less and 
the suggested revision to 30 horsepower has not been adopted.
    One commenter stated that modern compressor technologies allow for 
much safer rotary screw compressor operation using non-defeatable 
programmed safety controls, synthetic lubricants, automatic fire 
suppression and shutdown, and other precautions. Although synthetic 
lubricants offer some safety enhancement, they do not fully mitigate 
the hazards. Also, considering the accident history including the 
Wilberg disaster, MSHA has not provided an exemption for rotary screw 
compressors.
    Existing Sec. 75.344 (a)(1) requires all compressors to be located 
in noncombustible structures or areas and to be equipped with a heat-
activated fire suppression system. During informational meetings it was 
brought to MSHA's attention that in some instances requiring 
compressors to be inside such a structure could present a hazard 
through compressor overheating. Upon reviewing this potential effect of 
the regulation, MSHA agreed. Therefore, before the existing standard 
could become effective, MSHA stayed the application of paragraph (a)(1) 
and included the standard in this rulemaking.
    The final rule addresses the potential of compressor overheating by 
allowing a compliance alternative to enclosing the compressor. Heat is 
generated at considerable rates by operating compressors. Improperly 
used or maintained compressors can present a significant risk of fire. 
To minimize this hazard, the rule specifies other installation and 
operational requirements as well as providing for fire detection and 
fire suppression. As recommended by commenters, the final rule also 
provides for audible and visual alarms and automatic deenergization or 
shut-off.
    Several commenters discussed the proposed revisions to paragraph 
(a). One commenter urged that the term ``operation'' be clarified, 
noting that compressors which are designed to automatically start when 
necessary to rebuild air pressure should be protected. MSHA considers 
compressors that are installed to automatically start when necessary to 
rebuild air pressure to be in operation. MSHA agrees that these 
compressors should be provided either a noncombustible structure (or 
area) or an attendant. Accordingly, for the purpose of clarifying the 
requirement, the final rule includes the commenter's recommendations. 
Compressors which have been disconnected from the power or fuel source 
would not be subject to the requirement under the final rule.
    Another commenter suggested that the person specified in paragraph 
(a)(1) be trained. The commenter noted that the attendant would be of 
little value if unaware of the appropriate response to a fire. The 
commenter suggested that the person know how to deenergize the machine 
and activate the fire suppression system manually. MSHA agrees and 
notes that this knowledge is required under the proposal by requiring 
that the attendant be capable of performing these tasks. MSHA believes 
that any training necessary to meet this capability is implicit in the 
standard and the proposal has been retained under the final rule.
    Another commenter suggested that an attendant be accepted as an 
alternative to noncombustible structures or areas for a maximum of 8 
hours. The commenter stated that 8 hours would provide sufficient time 
for urgent roof bolting or construction work such as coating stoppings 
or powering a jack hammer. After considering the comment, the suggested 
time limit has not been adopted. MSHA believes that a continuous 
attendant, always within sight of the compressor and capable of 
responding as required, provides a level of protection equivalent to 
the protection provided by an enclosure. Therefore, the final rule 
allows either alternative to be selected. It should also be noted that 
the final rule has been revised to require either a continuous 
attendant or containment in a noncombustible enclosure or area.
    One commenter suggested that an alternative be provided in the rule 
to allow for video monitoring of compressors as an alternative to 
attendance or noncombustible enclosures. MSHA has not adopted the 
suggestion since video monitoring would not provide an equivalent level 
of safety compared to either an enclosure or attendance. There would be 
a considerable time delay in responding to a video monitor as compared 
to a nearby attendant who could immediately shut down the compressor, 
activate fire suppression, discharge fire extinguishers, apply rock 
dust, and take other necessary actions.
    Other commenters addressed an allowable distance within which the 
compressor attendant must remain. In the preamble to the proposal, MSHA 
solicited comments on the proposed language, ``can see the compressor 
at all times'' versus having the attendant 

[[Page 9790]]
remain within some specified distance. Rationale was solicited for any 
specific distances suggested. Several commenters supported the 
proposal, noting that adjustment is inherently provided for high mining 
heights and seam undulations since a low undulating seam would cause 
the attendant to remain closer to the compressor. Another commenter 
suggested that a maximum distance of 20 feet be specified. The 
commenter reasoned that a maximum distance of 20 feet would assure that 
the attendant could react to a fire quickly, noting that a compressor 
fire would propagate rapidly. The commenter also voiced a concern over 
travel time in low height mines and noted that distances over 20 feet 
might allow a fire to get out of control before the attendant could 
reach the machine.
    Another commenter was concerned with the proposed requirement in 
(a)(1) that a person be able to see the compressor at all times. The 
commenter suggested that the term ``close proximity'' be adopted noting 
that a person could be in close proximity, e.g. in an adjacent 
crosscut, but not within sight. The commenter suggested that this 
should be acceptable since the person would still be able to activate 
the fire suppression system. MSHA disagrees. The suggested situation is 
not acceptable since a considerable delay could result before detection 
of a problem if the person were not within sight of the compressor. In 
such a case the person would be relying on the smell of smoke or some 
indirect means of detecting a problem. Because of the potential fire 
hazard associated with compressors, reaction time is critical. MSHA 
continues to believe that reaction time is appropriately minimized if 
the assigned person can see the compressor at all times, is capable of 
deenergizing the unit, and is capable of activating the fire 
suppression system. While agreeing that reaction time is critical and 
after considering all of the comments, MSHA finds the arguments for not 
specifying a set distance to be more persuasive. Therefore, the final 
rule permits compressors to be continuously attended by a person 
designated by the operator who can see the compressor at all times 
during its operation. Any designated person attending the compressor 
must be capable of activating the fire suppression system and 
deenergizing or shutting-off the compressor in the event of a fire.
    If a compressor is not enclosed in accordance with (a)(2), the 
compressor can be operated only while it can be seen by a person 
designated by the operator according to (a)(1). In adopting this 
approach, the proposed paragraph (a)(1) language was deleted. 
Commenters indicated confusion over the similarity of proposed 
paragraphs (a)(1) and (b)(1) of the existing rule. The final rule 
combines these two requirements in (a)(1). The final rule requires both 
that the person be able to see the compressor and be capable of 
activating the fire suppression system.
    Paragraph (a)(2) of the final rule requires that compressors, if 
installed in a noncombustible structure or area, be ventilated by 
intake air coursed directly into a return air course or to the surface 
and be equipped with sensors to monitor for heat and for carbon 
monoxide or smoke. MSHA expects that an air quantity sufficient to cool 
the compressor will be provided through the enclosure. The 
manufacturer's operation manuals for compressors often specify an air 
quantity or a maximum ambient temperature. The sensors required by 
paragraph (a)(2) must deenergize power to the compressor, activate a 
visual and audible alarm located outside of and on the intake side of 
the enclosure, and activate doors to automatically enclose the 
noncombustible structure or area when either of the conditions in 
paragraph (a)(2)(i) or (ii) occurs. The visual alarm should be situated 
so that it can be seen by persons traveling in the intake entry 
immediately adjacent to the enclosure. The sensors must also deenergize 
or shut-off the compressor in addition to closing the doors of the 
enclosure.
    Paragraph (a)(1)(ii) specifies that the sensors shall deenergize 
power to the compressor, activate a visual and audible alarm located 
outside of and on the intake side of the enclosure, and activate doors 
to automatically enclose the noncombustible structure or area when the 
carbon monoxide concentration reaches 10 parts per million above the 
ambient level for the area, or the optical density of smoke reaches 
0.05 per meter. These levels are the same as required by the existing 
rule. As discussed in MSHA's opening statement at the ventilation 
rulemaking hearings, the value used for the optical density of smoke is 
based on information provided from the Bureau of Mines. MSHA pointed 
out that, based on comments received from the Bureau of Mines, this 
number is incorrect and should be divided by 2.303 to conform to the 
internationally accepted term of optical density. MSHA's remarks were 
made in reference to the requirement in Sec. 75.340(a)(1)(iii)(B). The 
final rule also makes a conforming technical revision to 
Sec. 75.344(a)(2)(ii).
    Paragraph (e) of the final rule requires automatic deenergization 
or automatic shut off of the compressor if the fire suppression system 
of paragraph (b) is activated. A number of commenters suggested that 
compressors should have an automatic shutdown feature that deenergizes 
or shuts-off the compressor when the required fire suppression system 
is activated. MSHA agrees. MSHA recognizes that under Sec. 75.1107-4 
automatic deenergization is required if the automatic fire suppression 
system is activated on unattended electrically powered compressors.
    Proposed paragraph (b)(2) has been omitted from the final rule. The 
paragraph was intended to provide additional flexibility for compressor 
installations located away from working sections and near a return air 
course where a substantial pressure differential exists. No comments 
were received in support of the proposed standard, while a number of 
comments were received in opposition. Commenters objecting to the 
standard raised concerns about overheating and stated that the 
revisions were made unnecessary in view of modified paragraph (a). MSHA 
agrees. Historically, when compressors that are on fire continue to 
operate, they often released oil into the environment, thus increasing 
the severity of the fire. For this reason, MSHA believes that safety is 
best served by requiring compressors to be deenergized or shut-off when 
the fire suppression system is activated. Commenters recommended 
deenergization in (a)(2) of the final rule. MSHA agrees and has the 
included automatic deenergization in (a)(2). One commenter suggested 
that alarms be automatically given at the section and surface and that 
two-way communications be provided at each compressor installation. 
This recommendation has not been adopted since the rule provides the 
desired level of safety through venting to the return, automatic fire 
extinguishment and closure of doors, in addition to the alarms outside 
the enclosure.

Section 75.360 Preshift Examination

    The preshift examination is a critically important and fundamental 
safety practice in the industry. It is a primary means of determining 
the effectiveness of the mine's ventilation system and of detecting 
developing hazards, such as methane accumulations, water accumulations, 
and bad roof.
    A considerable number of comments were received representing a 
range of opinions on the changes MSHA proposed. After consideration of 
all comments received, the final rule 

[[Page 9791]]
adopts certain modifications and clarifications to the existing 
standard to increase the effectiveness of the preshift examination. The 
final rule removes paragraph (e), redesignates existing paragraphs (f) 
through (h) as (e) through (g), revises paragraphs (a), (b), and (f) 
and adds new paragraphs (b)(8) through (b)(10).
    Existing paragraph (a) is divided into paragraphs (a)(1)and (a)(2) 
in the final rule. Paragraph (a)(1) of the final rule contains the 
existing general requirement that preshift examinations are to be 
conducted by certified persons designated by the operator. Paragraph 
(a)(1) also modifies the existing and proposed language in response to 
comments, to provide for preshift examinations at 8-hour periods. 
Paragraph (a)(2) of the proposed rule would have allowed pumpers to 
conduct an examination in lieu of the preshift examination under 
certain conditions. The final rule adopts this approach with 2 changes. 
The final rule does not require the pumper to examine for noncompliance 
with mandatory safety and health standards that could result in a 
hazardous condition and does require that records be made and retained 
in accordance with Sec. 75.363.
    A number of commenters addressed the application of this standard 
at mines where extended, overlapping, or other novel working shifts are 
employed. MSHA agrees with commenters that evolution within the 
industry in shift scheduling has presented a number of questions and 
controversies regarding the standard which must be resolved to assure 
that proper preshift examinations are conducted within suitable time 
frames. Based on comments, the final rule adopts a modification to 
clarify and standardize the application of the preshift examination in 
recognition of the use of novel shifts while maintaining the protection 
of the existing standard.
    Underground working schedules of three 8-hour shifts per day were 
virtually standard when the previous rule was implemented. Currently a 
substantial number of mining operations have work shifts of more than 8 
hours. Other operations stagger or overlap shifts providing for 
continuous underground mining activities. Some mines that operate 
around the clock schedule persons to begin shifts at one-or two-hour 
intervals. In such cases, controversies and misunderstandings have 
developed regarding application of the current standard.
    Commenters suggested that preshift examinations should be conducted 
for distinct 8-hour periods. Under this scenario a preshift examination 
for an 8-hour period would be acceptable for the entire 8-hour period 
regardless of shift schedules. Other comments indicate that this 
suggested modification would be consistent with the original intent and 
language of section 303(d)(2) of the Mine Act, which provides that no 
person, other than certified persons designated to conduct the 
examination, is permitted to enter any underground area unless a 
preshift examination of such area has been made within 8 hours prior to 
their entering the area. A commenter stated that to allow preshifts at 
more than 8-hour periods reduces the protection envisioned by the 
drafters of the Mine Act. MSHA understands the concerns and the 
critical nature of the preshift examinations to monitor the constantly 
changing conditions underground and has revised the rule accordingly to 
provide for an examination at 8-hour intervals.
    Under the final rule, operators will establish the 8-hour periods 
for which preshift examinations will be conducted. Persons may enter or 
leave the mine, regardless of their shift schedule during any 
established period for which a preshift examination has been conducted. 
However, another preshift examination must be completed prior to the 
next 8-hour period if any persons, other than examiners, remain in the 
mine. As always, no person other than examiners may enter any 
underground area prior to the completion of a preshift examination.
    The final rule requires three preshift examinations where persons 
are underground for more than 16 hours per day. At mines with only one 
8-hour shift per day only one preshift examination per day would be 
required. Mines working 10-or 12- hour shifts would conduct preshift 
examinations for each 8-hour period during which persons are 
underground. MSHA agrees with comments that the original legislation of 
the Mine Act envisioned that preshift examinations would be conducted 
for each 8-hour interval that persons worked underground. Similar to 
the existing requirement, the final rule does not require examinations 
for designated 8-hour periods when no one goes underground.
    MSHA recognizes that the final rule may cause a limited number of 
mines to perform examinations that are not currently required. These 
affected mines do not operate 24 hours per day but work one or two 
shifts which exceed 8 hours. For example, the final rule requires two 
examinations per day at a mine operating one 12-hour shift per day. 
When a mine operates two 10-hour shifts per day the final rule requires 
three examinations per day. The Agency has concluded that, considering 
the speed at which underground conditions can change, a reasonable 
period must be identified after which another examination is necessary. 
It is not MSHA's intent that the preshift be a continuous examination 
without a beginning or an end. Rather if the mine uses regular shifts 
that are longer than 8 hours in length, the preshift examination is 
good for an entire 8-hour interval. Those persons who start their work 
shift later than the normal shift start time do not need an additional 
preshift examination during the remainder of the 8-hour period. 
However, a preshift will be required if they are to stay in the area 
past the end of the 8-hour period. However, in accordance with 
longstanding practice, unplanned short excursions past the 8-hour 
period that occur infrequently will be accepted without an additional 
preshift. For example, miners required to stay an additional short 
period of time, such as 15 minutes to complete a mechanical repair, or 
due to a mantrip delay, would not need an additional preshift. The rule 
simplifies and clarifies the application of the standard at mines 
employing creative shift scheduling.
    Comments were received suggesting that the regulation should 
stipulate 12:00 a.m., 8:00 a.m., and 4:00 p.m. as the beginning of the 
8-hour periods for which preshift examinations would be required. This 
suggestion has not been adopted. There is no safety or health benefit 
to be gained through prohibiting operators from adopting other 8-hour 
intervals, e.g., 10:00 p.m., 6:00 a.m., and 2:00 p.m. Also, the 
standard is not intended to prevent operators from establishing their 
own work times. For example, an operator may elect a starting time of 
11:00 a.m. for a weekend project provided the preshift is completed 
within the 3 hours prior to the beginning of the shift.
    A commenter suggested that the final rule not require a preshift 
examination for non-coal producing shifts, where persons are to work in 
the shaft, slope, drift, or on the immediate shaft or slope bottom 
area. Under the commenter's suggestion, only that area immediately 
surrounding the bottom would need to be examined. The rationale given 
for the suggested change is that it is intended to bring the standard 
into conformity with ``certain state regulatory programs''. MSHA is not 
aware of state regulatory programs which would necessitate a change in 
the language of the final rule. Additionally, because areas where 
persons are not scheduled to work or travel are not required to be 
examined under the final rule, the 

[[Page 9792]]
change is unnecessary. Therefore, the suggestion of the commenter has 
not been adopted.
    Paragraph (a)(2) of the final rule provides that preshift 
examinations of areas where pumpers are scheduled to work or travel are 
not required prior to the pumper entering the areas, if the pumper is a 
certified person and the pumper conducts the specified examinations. 
This standard recognizes that pumpers travel to remote areas of the 
mine to check on water levels and the status of pumps, making regular 
preshift examinations impractical. The examinations required by pumpers 
include an examination for hazardous conditions, tests for methane and 
oxygen deficiency, and a determination of whether the air is moving in 
its proper direction in the area where the pumper works or travels. The 
examination of the area must be completed before the pumper performs 
any other work. A record of all hazardous conditions found by the 
pumper must be made and retained in accordance with Sec. 75.363.
    One commenter objected to the proposal stating that areas where 
pumpers work or travel should be preshift examined. The commenter 
stated that the proposed revision would weaken the protections provided 
under the existing standard, and that the rule would indirectly require 
that pumpers be certified. The commenter noted that most pumpers are 
not certified to perform examinations, and that it would be 
inappropriate to require ``hourly employees'' to obtain such 
certifications. The commenter further suggested that the proposed 
revision could infringe on the traditional relationship between labor 
and management wherein only management is required to be certified. The 
final rule does not require that pumpers be certified. Rather the final 
rule provides an option for pumpers to perform examinations for 
themselves if they are certified. Otherwise, areas where pumpers are 
scheduled to travel must be preshift examined by a certified person.
    The final rule maintains the existing level of safety. A complete 
examination by a certified person is still required and the examination 
will be conducted closer to the time that work is performed in the 
area. As with other examination requirements, no one may accompany the 
pumper during the examination. It is important to note that the 
examination performed by the pumper under paragraph (a)(2) is not 
acceptable if other persons have been scheduled to enter the area. The 
pumper may only perform an examination in lieu of a preshift for 
himself or herself. If, however, after the beginning of the preshift 
examination, persons are assigned to enter the area, the pumper may 
perform a supplemental examination for other persons in accordance with 
Sec. 75.361, provided that the certified pumper is designated by the 
operator to conduct such examinations.
    Commenters asserted that pumpers cannot conduct quality 
examinations and effectively perform their normal work duties. Under a 
previous standard replaced in 1992, persons such as pumpers, who were 
required to enter idle or abandoned areas on a regular basis in the 
performance of their duties, and who were trained and qualified, were 
authorized to make examinations for methane, oxygen deficiency and 
other dangerous conditions for themselves. Under the final rule, either 
a preshift examination must be made in accordance with paragraph (a)(1) 
before a pumper enters an area, or certified pumpers must conduct an 
examination under paragraph (a)(2).
    One commenter cited a 1984 incident at the Greenwich No. 1 mine 
where three miners were killed in an explosion while entering an idle 
area to work on a pump. The commenter suggested that an effective 
preshift examination would have prevented the accident and suggests 
that both a preshift examination and examinations by qualified pumpers 
should be required. An adequate preshift examination or supplemental 
examination as specified in the final rule, would prevent a similar 
result. One of these two examinations is always required under the 
final rule before persons enter any such idle area.
    Also in addressing paragraph (a)(2), one commenter suggested that 
some certified persons who are pumpers may not conduct adequate 
examinations. According to the commenter, certified persons conducting 
examinations under paragraph (a)(2) cannot be expected to perform at 
the same level as preshift examiners conducting examinations under 
(a)(1). MSHA expects that all certified persons who are required to 
conduct examinations, including certified pumpers, will conduct the 
examinations in accordance with the standards.
    Another commenter suggested that persons performing other jobs, 
such as rock dusters, should be permitted to perform examinations for 
themselves. Pumpers, unlike most other miners except mine examiners, 
travel in remote areas of the mine and normally work alone. Persons 
performing work such as rock dusting, however, normally work in newer 
areas of the mine where mining has only recently been completed and 
normally work as a part of a crew. Therefore, MSHA does not consider 
the work assignments to be similar enough to merit the same 
consideration and has not included this recommendation in the final 
rule.
    As proposed, paragraph (a)(2) would have required that the 
certified pumper examine for noncompliance with mandatory safety or 
health standards that could result in a hazardous condition, test for 
methane and oxygen deficiency, and determine if the air is moving in 
its proper direction in the area to be worked or traveled by the 
pumper. A number of commenters recommended the deletion of the 
requirement that the certified pumper identify and record noncompliance 
with mandatory safety and health standards that could result in a 
hazardous condition. Commenters cited a number of objections: the 
requirement would detract from miner safety, would significantly and 
unnecessarily increase the burden on examiners, would diminish the 
quality of the examination, would require excessive judgment and 
discretion by the examiners, and require examiners to make predictions. 
After considering all submitted comments, MSHA concludes that these 
comments have merit and the final rule does not require certified 
pumpers to examine for violations of mandatory safety and health 
standards that could result in a hazardous condition.
    Under paragraph (a)(2), a record of all hazardous conditions found 
by the pumper must be kept in accordance with Sec. 75.363. One 
commenter objected in that all of the records resulting from a preshift 
examination would not be required of the pumper, such as the locations 
of air and methane measurements and the results of methane tests. The 
commenter suggested that the full preshift record should be produced 
just as if the examination were done according to paragraph (a)(1). In 
the case of the pumper-examined area, the records required under 
paragraph (a)(2) will assure that mine management is made aware of any 
condition which results in a hazardous condition and will facilitate 
corrective actions being taken. It is important to note that the pumper 
is conducting an examination in a limited area only for himself or 
herself. This is in contrast to the various areas addressed in 
paragraph (a)(1), where the examination is in anticipation of one or 
many other miners entering these areas usually on a regular basis, all 
of whom are relying on the examiner's findings. In these circumstances, 
it is important that a record is made which can be 

[[Page 9793]]
utilized to spot ongoing problems and trends.
    Paragraph (b) of the rule specifies the nature of the preshift 
examinations and the locations where a preshift examination is 
required. Proposed paragraph (b) would have required that the person 
conducting the preshift examination would examine for noncompliance 
with mandatory safety or health standards that could result in a 
hazardous condition. After considering all submitted comments, the 
final rule does not contain this requirement.
    A number of commenters recommended the deletion of the requirement 
to identify and record noncompliance with mandatory safety and health 
standards that could result in a hazardous condition. Various 
commenters stated that the proposed requirement: would distract the 
examiner from the most important aspects of the preshift examination; 
would require predictions; would be an unrealistic expectation; and/or 
is designed only to facilitate enforcement actions. Commenters also 
suggested that the proposal would result in a shift in the focus of 
preshift examination from true hazards to noncompliance.
    Other commenters objected that the proposed requirement to examine 
for noncompliance with mandatory safety or health standards that could 
result in a hazardous condition is so vague that it could detract from 
miner safety. One commenter suggested that the examiners would spend 
their time performing permissibility checks, torquing roof bolts, 
measuring roof bolt spacing, and similar tasks which represent a 
significant departure from the examiners traditional duties.
    Another commenter expressed the opinion that paragraph (b) should 
require that all violations of mandatory safety or health standards be 
recorded and it should not be limited to those that could result in 
hazardous conditions. Preshift examinations assess the overall safety 
conditions in the mine; assure that critical areas are properly 
ventilated; assure that the mine is safe to be entered by miners on the 
oncoming shift; identify hazards, whether violations or not, for the 
protection of miners; and through this identification facilitate 
correction of hazardous conditions.
    The preshift examination requirements in the final rule are 
intended to focus the attention of the examiner in critical areas. This 
approach is consistent with the fundamental purpose of preshift 
examinations which is to discover conditions that pose a hazard to 
miners. MSHA is persuaded that to require examiners to look for 
violations that might become a hazard could distract examiners from 
their primary duties. The final rule, therefore, does not adopt this 
aspect of the proposal.
    Paragraph (b)(1) of the final rule adopts the proposal and 
clarifies that preshift examinations are to include travelways in 
addition to roadways and track haulageways. During informational 
meetings, commenters indicated that the terms ``roadways'' and ``track 
haulageways'' are associated with areas where mobile powered equipment 
is operated. By including the term ``travelways,'' the rule clarifies 
that areas where persons are scheduled to travel on foot are to be 
included, since hazards may also develop in these areas.
    One commenter suggested that the proposal would greatly increase 
the area that must be preshift examined, even though the requirement is 
limited to only those travelways where miners are scheduled to work or 
travel. This commenter suggested that in large mines many more areas 
than would actually be used by miners would have to be preshift 
examined. The premise of the preshift examination is that all areas 
where miners will work or travel be examined for hazards. The final 
rule change concerning ``travelways'' is intended only to clarify that, 
when miners are scheduled to use these areas, they must be preshift 
examined first. The final rule, therefore, does not expand the existing 
scope to the preshift examination requirements.
    The language of the existing paragraph (b)(1) referring to, ``* * * 
other areas where persons are scheduled to work or travel during the 
oncoming shift'' is transferred to a new paragraph (b)(10) with 
conforming changes, as proposed. MSHA received no comments on moving 
this provision to paragraph (b)(10). Commenters did respond to the 
phrase in proposed paragraph (b)(1) requiring preshift examinations of 
roadways, travelways and track haulageways where persons are ``* * * 
scheduled, prior to the beginning of the preshift examination to work 
or travel during the oncoming shift.'' The purpose of this proposal, 
which is adopted in the final rule with only clarifying changes, is to 
permit work and mining personnel to be rescheduled after the start of a 
shift. Preshift examinations, by their nature, must be completed before 
the start of the shift. Changes in conditions, however, such as a 
breakdown of equipment, can alter planned work schedules. To 
accommodate these circumstances, the final rule requires mine operators 
to design preshift examinations around the best information available 
at the time the preshift begins. If changes must be made, Sec. 75.361 
specifies that areas not preshift examined be covered by a supplemental 
examination performed by certified persons before miners enter the 
area.
    One commenter objected that was confusing and should be modified. 
Other commenters foresaw possible abuses of the flexibility offered by 
the rule with some operators performing supplemental rather than 
preshift examinations, claiming that assignments were made after the 
preshift examination begins. After considering the comments, MSHA has 
retained the proposed flexibility to preshift examine areas where 
miners are scheduled to work or travel. To require more than this would 
be impractical.
    Section 75.360(b)(3) of the final rule requires preshift 
examinations of working sections and areas where mechanized mining 
equipment is being installed or removed if anyone is scheduled to work 
on the section or in the area during the oncoming shift. A discussion 
of the reproposal of provisions concerning the installation and removal 
of mechanized mining equipment is presented in the General Discussion 
section of this preamble. As with the existing rule, the examination 
includes working places, approaches to worked-out areas, and 
ventilation controls on these sections or in these areas. The final 
rule, like the proposal, adds a new requirement that the examination 
also include a test of the roof, face and rib conditions on these 
sections or in these areas.
    Proposed changes to paragraph (b)(3) not adopted in the final rule 
would have also required preshift examination of sections not scheduled 
to operate but capable of producing coal by simply energizing the 
equipment on the section. Also, proposed changes to paragraphs (c), 
(c)(1), and (c)(3) specifying where air volume measurements were to be 
taken on these sections have also not been adopted in the final rule.
    The new requirement to test the roof, face and rib conditions is 
added because of the importance of this test to the safety of miners. 
In newly mined areas, checking roof, face and rib stability is most 
important to preventing injuries and death. Comments were received in 
support of the revision, citing accidents which might have been 
prevented had such tests been adequately performed during preshift 
examinations. One commenter, when suggesting new wording for paragraph 
(b)(3), indicated that the requirement to test the roof, face and rib 
conditions should be deleted but 

[[Page 9794]]
did not offer any rationale for the suggested deletion. Another 
commenter suggested that the preshift examination should only require a 
visual examination of the roof, rather than a physical examination. 
Physical examinations of the roof, such as ``sounding,'' have been a 
historically accepted method for examiners to test roof competency. 
Whenever an examiner has a question as to whether a section of roof is 
competent, such a test should be performed.
    Comments were mixed on MSHA's proposed revision to include idle 
working sections as part of the preshift examination. The proposal is 
not retained in the final rule. Some commenters objected to the 
proposal as unnecessary, burdensome, or impractical. Commenters 
believed that the existing Sec. 75.361 requirement for supplemental 
examinations prior to anyone entering into such an area was sufficient. 
Commenters also stated that a preshift examination in these areas could 
introduce a false sense of security and that the effect would be to 
divert preshift examiners from more important duties. One commenter 
stated that the proposed requirement would be inconsistent with and 
contradictory to the basic concept of preshift examinations. Another 
commenter objected to MSHA's statement in the preamble to the proposal 
that there is a reasonable likelihood that miners will at some point 
during a working shift enter sections that are set up to mine coal.
    In support of the proposed requirement to preshift examine idle 
sections, one commenter cited explosions at the Red Ash Mine in 1973, 
the Scotia Mine in 1976, the P&P Mine in 1977, the Ferrell #17 in 1980, 
the Greenwich #1 Mine in 1984, and the 1994 explosion at the Day Branch 
No. 9 Mine in Kentucky. As the commenter pointed out, in each of these 
accidents miners were sent into an area that had not been preshift 
examined. However, none of these accidents were the result of miners 
entering areas that would have been covered by the proposal. In each 
instance, miners entered an area where mining had ceased, but could not 
be resumed by simply energizing equipment. Another common thread in 
each of these explosions was the failure of the operator to conduct the 
required supplemental examination prior to miners entering the area on 
an unscheduled basis.
    Paragraph (b)(4) of the final rule requires preshift examinations 
to include approaches to worked-out areas along intake air courses and 
at the entries used to carry air into worked-out areas if the intake 
air passing the approaches is used to ventilate working sections where 
anyone is scheduled to work during the oncoming shift. The examination 
of the approaches to the worked-out areas is to be made in the intake 
air course immediately inby and outby each entry used to carry air into 
the worked-out area. The examination of the entries used to carry air 
into the worked-out areas is to be at a point immediately inby the 
intersection of each entry with the intake air course. The standard is 
intended to assure that miners are not exposed to the hazards 
associated with ventilating working sections with contaminated air 
which has passed through a worked-out area. The requirement is 
consistent with the Sec. 75.301 definition of ``return air'' and with 
Sec. 75.332 which provides that working sections and other specified 
areas must be ventilated with intake air.
    Commenters correctly noted that a clarification was needed in the 
first sentence of proposed paragraph (b)(4) to indicate that the 
examination at the specified points is only required if the intake air 
passing the approaches is used to ventilate working sections where 
anyone is scheduled to work during the oncoming shift. Commenters 
suggested that an examination should not be required if the intake air 
is not used to ventilate working sections or if no one is scheduled to 
work on the section. This was the result intended by the proposal and 
the final rule has been revised accordingly.
    One commenter also suggested that the requirement in paragraph 
(b)(4) is unnecessary because the safeguards in the approved mine 
ventilation plan should prevent an air reversal in a worked-out area in 
which this air would enter the intake air course. The commenter offered 
the example of a worked-out area connected directly to a bleeder 
system. MSHA agrees that when proper safeguards are in place and 
operating as intended, air reversals are unlikely. However, roof falls 
and other obstructions in the worked-out area or in the bleeder can 
cause air reversals, permitting return air to enter the intake and be 
transported to the working section. Without a suitable examination, 
this condition would go undetected and could lead to disaster. While 
not exactly the same, the explosion at the Pyro Mine in 1989, which 
resulted in the deaths of 10 miners, was the result of a somewhat 
similar set of circumstances. A water blockage in the bleeder entry 
that combined with changes to certain ventilation controls led to 
methane migrating from the worked-out area onto the longwall face. 
MSHA's report of this accident concludes, in part, that changes that 
occurred during the mining of the longwall panel and in the bleeder 
entries caused a fragile balance of air flows to exist in the 
ventilation system that permitted methane to migrate from the gob and 
to accumulate near the longwall headgate.
    One commenter agreed with the proposal and discussed the need to 
assure that miners are not exposed to the hazards associated with 
ventilating working sections with return air.
    Essentially, the final rule requires that at each applicable 
approach, three examinations must be made; immediately inby and outby 
the approach in the intake entry and in the approach itself immediately 
inby the intersection with the intake entry. Situations exist where 
multiple openings along an intake lead into a worked-out area. Under 
some conditions intake air enters the upstream openings, passes through 
the worked-out area, and then re-enters the intake. The examination 
required by paragraph (b)(4) is designed to assure that such a 
condition is detected. Also, the examination detects any change in 
ventilation entering the worked-out area which may warrant follow-up or 
corrective actions to assure that the worked-out area is ventilated.
    Paragraph (b)(6) of the final rule adopts the proposal modifying 
the existing rule. No comments were received on this aspect of the 
proposal. The final rule in paragraph (b)(6)(i) requires preshift 
examinations to include entries and rooms developed after November 15, 
1992 (the effective date of the existing rule), and developed more than 
2 crosscuts off an intake air course without permanent ventilation 
controls where intake air passes through or by these entries or rooms 
to reach a working section where anyone is scheduled to work during the 
oncoming shift. Similarly, under (b)(6)(ii) the examination must 
include entries and rooms developed after November 15, 1992, and driven 
more than 20 feet off an intake air course without a crosscut and 
without permanent ventilation controls where intake air passes through 
or by these entries or rooms to reach a working section where anyone is 
scheduled to work during the oncoming shift.
    Existing paragraph (b)(6) requires that a preshift examination be 
made in all entries and rooms driven more than 20 feet off an intake 
air course without a crosscut or more than 2 crosscuts off an intake 
air course without permanent ventilation controls where intake air 
passes through or by these entries or rooms to a working section where 
anyone is scheduled to work during the oncoming shift. MSHA proposed 

[[Page 9795]]
modifications to existing paragraph (b)(6) based on concerns raised 
following publication of the existing rule on May 15, 1992. Commenters 
at that time indicated that extensive rehabilitation would be required 
at a number of mines to implement the standard in the rooms and entries 
described in the rule, causing diminished safety for miners performing 
the rehabilitation work. Commenters noted that some areas had been 
timbered heavily and cribbed because of adverse roof conditions and 
that rehabilitation would unnecessarily expose miners to roof falls and 
rib rolls while removing or repositioning roof support. In addition, 
roof conditions in some areas would remain hazardous even after 
rehabilitation. The commenters also noted that many such areas had been 
in existence for many years without incident and that any methane 
liberation had long since stopped due to the passage of time. They 
noted that some areas cannot be effectively sealed and that the risks 
associated with rehabilitation and subsequent physical examinations 
would greatly outweigh the safety benefit to be gained. MSHA recognizes 
the legitimate concerns raised by the commenters and the final rule 
requires preshift examination of entries and rooms developed after 
November 15, 1992 and driven more than 20 feet off an intake air course 
without a crosscut or more than 2 crosscuts off an intake air course 
without permanent ventilation controls where intake air passes through 
or by these entries or rooms to a working section where anyone is 
scheduled to work during the oncoming shift. MSHA believes, however, 
that the conditions addressed by paragraph (b)(6) are the result of 
improper mining practices in the past. These mining systems should be 
revised in the future to avoid poor conditions, or the areas affected 
should be fully and reliably ventilated and be examined. Also, the 
final rule applies only to entries and rooms developed after the 
effective date of the existing rule. As such, the mining industry was 
on notice of the shortcomings of mining practices that left entries and 
rooms of the type addressed by the standard.
    Paragraph (b)(8) retains the proposal requiring preshift 
examinations to include high spots along intake air courses where 
methane is likely to accumulate, if equipment may be operated in the 
area during the shift. As noted in the proposal, it has long been 
recognized that methane can accumulate in high areas with no 
indications being detected in the lower portions of the opening. As 
mobile equipment passes under these areas or a conveyor belt is put 
into operation, the methane is pulled down and mixed with the air in 
the entry and may be ignited. The final rule addresses the hazards of 
undetected accumulations of methane in high spots by requiring preshift 
examinations in such areas in intake air courses if equipment will be 
operated in the area during the shift.
    Several commenters requested that MSHA clarify the term ``high 
spots.'' One commenter stated that many hours would be necessary to 
examine every indentation in the roof of a large mine and stated the 
belief that the turbulence created by passing equipment would render 
harmless any of the small amounts of methane that might possibly 
accumulate. Another commenter believed the requirement was unnecessary 
because there has never been a problem with methane accumulating in 
intakes in quantities sufficient to cause an explosion. One commenter 
suggested that the requirement should only be applicable to mines with 
a demonstrated history of methane accumulations, noting that although 
mines are considered likely to liberate methane, it is not likely that 
all mines will accumulate methane in high spots.
    Another commenter suggested that preshift examinations should be 
required in all high spots in intakes, returns, belt entries, and track 
haulage entries. The commenter also objected to limiting the 
examination in intakes only to areas where equipment may be operated 
during the shift. The commenter observed that methane can accumulate 
quickly in high spots and that it is critical to detect the methane 
before it creates a danger. The commenter notes several accidents 
involving methane accumulations in high spots, including: Meigs No. 31 
Mine in 1993 where methane in a roof cavity was ignited by a torch; VP-
5 Mine in 1992 when methane in a cavity was ignited by a torch; Ferrell 
No. 17 Mine in 1980 where, according to the commenter, methane may have 
accumulated in a cavity in the belt entry roof and may have been 
ignited by a trolley powered vehicle; and in the VP-6 in 1982 where 
methane in a high spot was ignited by a trolley powered vehicle 
traveling through the area. The commenter stated that accumulations of 
methane in high spots can be ignited by any number of sources.
    A meaningful preshift examination requires that conditions which 
can lead to an explosion or ignition be detected and corrected before 
miners begin their work. In addition to the accidents cited above 
attributed to methane accumulations in high spots, the Itmann No. 3 
Mine explosion occurred when a trolley powered vehicle ignited methane 
in a high spot, resulting in the death of 5 miners and severe burns to 
2 other miners. The phrase ``high spots where methane is likely to 
accumulate'' should be understood in the coal mining industry. 
Experienced miners, and in particular preshift examiners and certified 
persons, can readily recognize a high spot where methane is likely to 
accumulate. Also, MSHA for many years has considered preshift 
examinations to be inadequate where examinations did not include 
methane tests in these areas. An examination of ``every indentation,'' 
as foreseen by one commenter is not expected nor intended by paragraph 
(b)(8), which specifies that preshift examinations be used to identify 
methane hazards by testing in the appropriate locations. The final rule 
does not adopt the suggestion that methane examinations be based on 
mine liberation history since significant methane liberation may begin 
or can greatly increase at any time. Also, the potential for a 
dangerous accumulation of methane in a high spot is influenced by mine 
ventilation, particularly the air velocity in the entry.
    One commenter suggested that the rule require tests only in 
``unventilated high spots'' along intake air courses. The final rule 
does not adopt this approach. The purpose of the preshift examination 
is to detect hazards, in this case accumulations of methane. Nominal 
ventilation in a high roof cavity may not be sufficient to sweep away 
methane and an accumulation could exist. The final rule directs an 
examiner's attention to such situations.
    Proposed paragraph (b)(9) is modified in the final rule. Paragraph 
(b)(9) of the final rule requires preshift examinations at underground 
electrical installations referred to in Sec. 75.340(a), except those 
water pumps listed in Sec. 75.340(b)(2) through (b)(6), and areas where 
compressors subject to Sec. 75.344 are installed if the electrical 
installation or compressor is or will be energized during the shift. 
The proposal would have exempted all water pumps from the requirements 
of paragraph (b)(9).
    One commenter objected to the exemption for pumps and recommended 
that all pumps be examined pointing out that some pumps are large, 
high-horsepower units. The commenter noted a 1994 case in Virginia 
where a 200 horsepower pump exploded. Pumps of this type may be in 
locations or in applications that would not be examined by pumpers 
under paragraph (a)(2). The final rule responds 

[[Page 9796]]
to this issue by requiring that all pumps should not be exempted from 
the standard. Paragraph (b)(9) requires preshift examinations of all 
pumps, except those specified in Sec. 75.340(b)(2) through (b)(6). 
Pumps specified in Sec. 75.340(b)(2) through (b)(6) and other pumps 
that operate automatically or that otherwise may be energized are 
generally in the more remote areas of the mine and are to be examined 
weekly in accordance with Sec. 75.364.
    Pumps which will be examined by certified pumpers in accordance 
with paragraph (a)(2) are not covered by the final rule because of the 
limited hazards they pose and because certified pumpers would 
themselves conduct examinations of this equipment in accordance with 
paragraph (a)(2). Examinations by pumpers at these locations will 
assure that methane has not accumulated and that the equipment is not 
in a condition to create a fire or ignition source.
    A review of the accident history reveals a number of fires in 
equipment that, under the final rule, would be subject to preshift 
examinations. For example, the compressor that MSHA identified as the 
probable cause of the fire in the Wilberg Mine, which killed 28 miners, 
would have required a preshift examination under (b)(9) of the final 
rule. Additionally, MSHA has identified several fires associated with 
rectifiers and transformer installations in the mining industry. One of 
these transformer fires was discovered during a preshift examination.
    One commenter supported proposed paragraph (b)(9) and noted a 
number of ignitions involving trolleys. The commenter also noted that 
history demonstrates that other electrical installations present 
ignition or fire hazards which should be examined before each shift.
    One commenter incorrectly understood proposed paragraph (b)(9) to 
not require preshift examinations of areas where compressors subject to 
Sec. 75.344 are installed if the compressor is or will be energized 
during the shift. The standard does require preshift examinations of 
such equipment, which includes all compressors except those which are 
components of equipment such as locomotives and rock dusting machines 
and are compressors of less than five horsepower.
    Paragraph (b)(10) adopts the proposal that preshift examinations 
include other areas where work or travel during the oncoming shift is 
scheduled prior to the beginning of the preshift examination. This 
provision recognizes that work requirements and situations may change 
after the preshift examination has begun. Often, once the examination 
has started it is not possible to contact the examiners to direct them 
to newly identified areas where miners will work. In these cases, a 
supplemental examination is required before persons work or travel in 
these areas. As discussed in the preamble to the proposal, paragraph 
(b)(1) requires preshift examinations of any underground area where 
persons are scheduled to work or travel during the oncoming shift. 
Under the existing rule, an operator did not have the flexibility to 
modify work assignments after the preshift examination had begun, 
unless it was possible to contact and redirect the examiners to perform 
a preshift examination before the beginning of the shift. Commenters in 
general supported the proposal. One commenter, however, while 
supporting the change expressed concern that the provision could be 
abused. MSHA does not anticipate abuse of the rule and believes it to 
be a reasonable approach to assuring that areas where persons work or 
travel are examined.
    As discussed above, the final rule does not adopt the proposed 
revisions to paragraphs (c), (c)(1), and (c)(3) and instead retains the 
language of the existing standard. While commenters to proposed 
paragraphs (c), (c)(1), and (c)(3) objected to expanding air volume 
measurements made during preshift examinations to sections where coal 
could be mined by simply energizing the equipment, no comments were 
received objecting to retaining the requirement for areas where 
equipment is being installed or removed. An in-depth discussion of the 
reproposal of provisions concerning the installation and removal of 
mechanized mining equipment is presented in the General Discussion 
section of this preamble.
    Paragraph (f) of the final rule sets out the requirements for 
recording and countersigning both the results of the preshift 
examination and actions taken to correct hazardous conditions found 
during the preshift examination. The final rule adopts the following 
proposed revisions to the existing rule: a record of the results of the 
preshift examination is required to be made; the results of methane 
tests are required to be made in terms of the percentage of methane 
found; and a certified person is required to record the actions taken 
to correct hazardous conditions found during the preshift examination.
    Additionally, paragraph (f) of the proposal would have required 
countersigning by both the mine foreman and the superintendent or 
equivalent individual to whom the mine foreman reports. The final rule 
does not require this second level countersigning. Also, the final rule 
allows an official equivalent to a mine foreman to sign the records. 
Finally, the final rule allows for secure storage of records in a way 
that is not susceptible to alteration and the records can be kept in a 
book or in a computer system.
    Commenters suggested that the final rule only require the examiner 
to record uncorrected hazardous conditions and not those which were 
corrected by the end of the shift. Commenters characterized the 
reporting of corrected hazardous conditions as unnecessary and 
unjustified by the accident history.
    MSHA did not adopt the proposal to record corrected defects found 
during the fan examination required by Sec. 75.312. MSHA believes, 
however, that a record of all hazards found during the preshift 
examination, including those corrected, is necessary. The record serves 
as a history of the types of conditions that are being experienced in 
the mine. When the records are properly completed and reviewed, mine 
operators can use them to determine if the same hazardous conditions 
are occurring repeatedly and if the corrective action being taken is 
effective. Additionally, this record can permit mine management, the 
representative of miners, and the representative of the Secretary to 
better focus their attention during examinations and inspections. The 
safety value of a complete record is illustrated by the 1989 explosion 
at Pyro Mining Company's William Station Mine in which 10 miners were 
killed. MSHA's accident investigation report concludes that methane 
concentrations of up to 6.5 percent were detected in the explosion area 
prior to the explosion but reports by the mine foreman for the shift 
failed to record the presence of these dangerous accumulations of 
methane or show the action taken to correct the condition. The 
investigation further found that the failure to record these methane 
accumulations in the appropriate record books prevented management 
officials and other interested persons from learning of the hazardous 
condition and initiating corrective action. In light of the record, the 
final rule adopts the proposal and requires the examiner to record the 
results, whether corrected or not, of the preshift examination and the 
action taken to correct hazardous conditions found during the preshift 
examination. This would include hazardous conditions and their 
locations and the results of methane and air measurements required to 
be made elsewhere in Sec. 75.360. 

[[Page 9797]]

    As with other records required by this rule, the records of 
preshift examinations may be kept either in secure books that are not 
susceptible to alteration or electronically in a computer system so as 
to be secure and not susceptible to alteration. A detailed discussion 
of record books and the use of computers to maintain records can be 
found in the General Discussion of this preamble.
    A variety of comments were received regarding the countersigning of 
preshift records by the mine foreman, and the time permitted for 
countersigning. The final rule adopts the proposal that the mine 
foreman or equivalent mine official must countersign the record of the 
preshift examination by the end of the mine foreman's next regularly 
scheduled working shift. The mine foreman is in a position of 
responsibility for the day-to-day operation of the mine. It is 
essential for the health and safety of the miners that the mine foreman 
be fully aware of the information contained in the preshift examination 
reports so as to be able to allocate resources to address safety 
problems. Allowing until the end of the mine foreman's next regularly 
scheduled working shift to countersign the reports provides sufficient 
flexibility to make compliance practical while assuring that the mine 
foreman is aware of the results of the examination in a reasonably 
timely manner.
    Some commenters suggested that the time for countersigning is 
unnecessarily long, and that the final rule should restore a previous 
requirement that countersigning be completed ``promptly.'' The term 
``promptly'' involves ambiguity that is eliminated by specifying the 
time for countersigning the preshift examination record. The rulemaking 
record does not show that the time set by the final rule would expose 
miners to safety or health risks. Commenters suggested that the term 
``mine foreman'' be replaced by a ``certified person responsible for 
ventilation of the mine or his designee.'' Another commenter suggested 
that the record could be countersigned by the mine foreman or any other 
mine official responsible for the day-to-day operation of the mine. 
Commenters stated that some operations no longer use the terms ``mine 
foreman,'' ``mine manager,'' or ``superintendent''. To provide for 
alternative management titles, the final rule incorporates the phrase 
``or equivalent mine official.''
    Numerous comments were received regarding the proposal for second 
level countersigning of the preshift examination record by the mine 
superintendent, mine manager, or other mine official to whom the mine 
foreman is directly accountable, within 2 scheduled production days 
after the countersigning by the mine foreman. The final rule does not 
retain this proposed requirement. A detailed discussion of the subject 
of second level countersigning can be found in the General Discussion 
section of this preamble.
    Paragraph (f) of the final rule also contains revisions to the 
existing rule to allow for electronic storage of records. Paragraph (g) 
requires that the records required by Sec. 75.360 be maintained at a 
surface location at the mine for one year and be made available for 
inspection by authorized representatives of the Secretary and the 
representatives of miners. A discussion of comments concerning the use 
of computers to maintain records can be found in the General Discussion 
of this preamble.

Section 75.362 On-Shift Examination

    Like the preshift examination, the on-shift examination of working 
sections is a long accepted safety practice in coal mining. As coal is 
extracted, conditions in the mine continually change and hazardous 
conditions can develop. Because the mining environment changes 
constantly during coal production, this examination identifies emerging 
hazards or verifies that hazards have not developed since the preshift 
examination. Generally, the on-shift examination includes tests for 
methane and oxygen deficiency, an examination for hazardous conditions, 
and air measurements at specified locations.
    The final rule adopts proposed Sec. 75.362 with the exception that 
revisions have been made to the proposed provisions dealing with an 
examination for compliance with the mine ventilation plan requirements 
for respirable dust control.
    The final rule redesignates existing (d)(1)(i) and (ii) as 
(d)(1)(ii) and (iii), revises paragraphs (a)(1), (c)(1), (d)(1)(iii) 
and (d)(2), removes paragraph (a)(2), and adds new paragraphs (a)(2) 
and (d)(1)(i). Additionally, the requirements of existing paragraphs 
(g) and (h), recordkeeping and retention, are transferred to 
Sec. 75.363, Hazardous conditions, posting, correcting, and recording. 
New paragraphs (g)(1) and (g)(2) are also added by the final rule.
    The word ``on-shift'' has been added to the first sentence of 
paragraph (a)(1) for clarity and consistency with other paragraphs of 
Sec. 75.362. MSHA did not receive any comments on this proposed 
revision. Paragraph (a)(1) is also revised as proposed to require a 
certified person designated by the operator to conduct an on-shift 
examination of each section where anyone is assigned to work during the 
shift and any area where mechanized mining equipment is being installed 
or removed during the shift. The existing rule required that an on-
shift examination be performed only on sections where coal is produced 
and areas where mechanized mining equipment is being installed or 
removed. Some commenters agreed that many of the same hazards exist on 
a section whether coal is being produced or not. Commenters gave 
several examples of activities that take place on non-coal producing 
sections including equipment repair and maintenance, cutting and 
welding, rockdusting, clean-up, and roof bolting. As indicated by these 
commenters, all of these activities present the potential for a serious 
accident. One commenter arguing against the proposed change stated that 
the preshift and supplemental examinations already address the safety 
concerns to which the proposal was directed. While MSHA considers the 
preshift and supplemental examinations to be of great importance in 
providing a safe work environment, these examinations are performed 
prior to workers on a shift entering the mine or, in the case of the 
supplemental examination, in an area of the mine that has not been 
preshift examined. The on- shift examination is intended to address 
hazards that develop during the shift. The concept of the on-shift 
examination is not new. On-shift examinations of coal producing 
sections have been required since the enactment of the Federal Coal 
Mine Health and Safety Act of 1969.
    Another commenter arguing against expanding the on-shift 
examination requirement to non-coal producing sections stated that 
requiring on-shift examinations of areas other than working sections 
would detract from other required examinations. On-shift examinations 
on coal producing sections are normally conducted by section foremen 
who spend the vast majority of the shift on the section they are 
supervising. These individuals will not normally conduct the on-shift 
examinations in non-coal producing sections. These examinations will be 
conducted by certified persons assigned to work in these areas or other 
certified persons assigned to conduct these examinations. MSHA does 
not, therefore, foresee reduced attention to examinations in working 
sections.
    Another commenter suggested that the requirements for on-shift 
examinations be expanded further than proposed. The commenter stated 
that many of the same types of activities that 

[[Page 9798]]
occur on non-production shifts on the sections also occur in outby 
areas of mines. In support of this recommendation the commenter pointed 
to 4 explosions which occurred in outby areas of the mines. Those 
accidents were the explosions at the Greenwich Collieries No. 1 Mine in 
Pennsylvania in February 1984 where 3 miners were killed; the explosion 
at the Day Branch Mine in Kentucky in 1994 where 2 miners lost their 
lives and; an ignition at the Loveridge No. 22 Mine in West Virginia in 
1992 that burned 1 miner. In each accident, several violations of 
safety standards contributed to the explosion or ignition, including 
inadequate or entirely omitted examinations required by standards in 
effect at the time. Compliance with those safety standards would have 
significantly reduced the likelihood of these tragic accidents 
occurring. Likewise, requirements of this final rule, such as the 
requirements for preshift and supplemental examinations in areas where 
persons are assigned to work or travel, would have served well to 
prevent these accidents.
    The final rule requirements for on-shift examinations focus on the 
areas most likely to develop hazards during a shift. Expanding the 
examination requirements further is not supported by the record nor 
needed for miner safety.
    As proposed, the final rule also revises paragraph (a)(1) to 
clarify that sufficient on-shift examinations must be conducted to 
assure safety. One commenter suggested that MSHA should include 
language to require more than one examination if necessary for safety, 
as provided for in the previous standard. The final rule adopts this 
approach and requires that at least once during each shift, or more 
often if necessary for safety, a certified person designated by the 
operator must conduct an on-shift examination of each section where 
anyone is assigned to work during the shift and any area where 
mechanized mining equipment is being installed or removed during the 
shift. As with other changes to this section, comments were received 
both supporting and opposing the change. One commenter in opposition to 
the standard argued that although the operator is required to maintain 
a safe work environment at all times, documentation should not be 
required for each inspection that is made of the working environment 
throughout the shift. The commenter is correct in stating that the 
rule, in Sec. 75.363, requires additional documentation. However, the 
only additional documentation required will be for hazardous conditions 
found during the additional on-shift examination conducted on non-coal 
producing sections where miners are working. The additional 
documentation required does not override the need for the standard. 
Another commenter suggested that the term ``more often if necessary for 
safety'' be changed to ``more often if necessary for safety as 
determined by the operator depending on the mining conditions at the 
time.'' This commenter stated that conducting additional checks for 
safety is a current practice and individuals working on the section, 
including the section foreman, are the most familiar with conditions in 
that area and should make the determination whether additional 
examinations are needed. MSHA agrees with this commenter that persons 
working on a section are in the best position to identify the need for 
additional examinations. The suggested language has not been adopted, 
however, because MSHA believes that this determination should not be 
limited to persons working on the section.
    Another commenter supported the proposal and listed explosions that 
have occurred which, in the opinion of the commenter, could have been 
prevented had additional on-shift examinations been made. MSHA agrees 
that there are occasions when additional on-shift examinations are 
necessary for safety and, therefore, the final rule requires that on-
shift examinations be conducted at least once each shift, or more often 
if needed for safety.
    The final rule retains the existing provision of paragraphs (a)(1), 
(c)(1) and (c)(2) requiring an on-shift examination of areas where 
mechanized mining equipment is being installed or removed. An in-depth 
discussion of the reproposal of provisions concerning the installation 
and removal of mechanized mining equipment is presented in the General 
Discussion section of this preamble.
    Paragraph (a)(2) adds a new on-shift examination requirement to 
address respirable dust control. Under the final rule, before coal 
production begins on a section, an examination for compliance with the 
dust control measures established in the mine ventilation plan must be 
completed. This examination includes measurement of air quantities and 
velocities, water pressures and flow rates, a check for excessive 
leakage in the water delivery system, and checks of the number of 
operating water sprays and their orientation as well as the placement 
of section ventilation control devices.
    Assuring full compliance with these requirements is important in 
safeguarding the health of miners. Human and financial costs 
demonstrate the need for further attention. In 1990, approximately 2000 
deaths were associated with Coal Worker's Pneumoconiosis and the total 
number of deaths between 1968 and 1990 were over 55,000. As of 1993, 
total annual Black Lung Program costs were over $1.3 billion and the 
cumulative total cost had exceeded $30 billion.
    Agency experience shows that needed attention has not always been 
given to the proper functioning of respirable dust controls. For 
example, a series of special spot inspections, undertaken in 1991 to 
conduct checks of the dust control parameters during the course of 
working shifts, revealed that 21 percent of the 781 mining units 
sampled were not complying with one or more of their dust control 
parameters. In its 1992 report, an MSHA Task Group recommended coal 
mine operators be required to make periodic on-shift examinations to 
verify that the mine ventilation plan parameters are in place and 
functioning as intended. MSHA considers on-shift examinations of 
respirable dust controls an important part of reasonable and prudent 
respirable dust control strategy.
    Several methods of measuring water spray pressures would be 
acceptable. For example, water flow and pressure can be monitored 
through the installation of an in-line water meter and a pressure 
transducer. Water pressure can also be measured by permanently 
installing a pressure gauge on a machine. Operators would determine the 
working relationship between the pressure gauge reading and the actual 
operating pressure at the sprays. Once the working relationship has 
been established, the gauge pressure could be used to indicate the 
actual spray pressure specified in the mine ventilation plan for a 
given number and type of operating sprays.
    Measurement of any required water flow rate could be accomplished 
through the installation of a flowmeter. A flowmeter provides a direct 
and reliable measurement and is the preferred method of determining 
water flow rate. Another acceptable method of determining flow rate 
would be to establish the relationship between the water pressure and 
the spray orifice diameter, either through engineering data or through 
actual tests. Once established, the water pressure gauge reading could 
be used to reliably indicate a flow rate for a specific number of 
sprays at a given orifice size.
    One commenter, while generally supportive of the requirement for an 
on-shift examination of respirable dust controls, expressed concern 
over permitting the use of in-line flowmeters 

[[Page 9799]]
and pressure transducers. The commenter stated that leaks in the 
location of the flowmeter and pressure transducer could go undetected, 
resulting in a loss of pressure and flow at the sprays. MSHA agrees 
that undetected leaks could result in improper operation of the system. 
To address this point, the final rule has been revised from the 
proposal to require that a check for excessive leakage in the water 
delivery system be made during the on-shift. This commenter also 
suggested that use of incorrect spray nozzles could result in improper 
operation of the system that would not be detected with in-line 
flowmeters and pressure transducers. MSHA would expect that as part of 
the examination of the number of operating sprays a check would be made 
to assure that the proper sprays are being used.
    The final rule requires that the number of water sprays and their 
orientation be included in the examination. While spray orientation is 
important in air-directing spray systems, such as sprayfans and 
shearer-clearers, MSHA does not intend that precise angles be 
determined during each examination. Rather, the examiner would be 
responsible for assessing whether the direction and orientation of the 
sprays are generally correct and in accordance with the requirements of 
the mine ventilation plan.
    The final rule also requires that the working section ventilation 
and control device placement be examined for compliance with the mine's 
ventilation plan. Mine ventilation, particularly where coal extraction 
occurs, is a basic respirable dust control measure.
    Any other respirable dust controls specified in the approved mine 
ventilation plan are also included in the scope of the examination 
required under the final rule. An example of such controls is the 
cleaning and maintenance procedures for a wet bed scrubber installed on 
a continuous mining machine. The examination would include a check to 
assure that air inlets and discharges are not plugged. It is not MSHA's 
intent that the air quantity produced by a machine-mounted scrubber be 
measured as part of the on-shift examination required by paragraph 
(a)(2), unless such a requirement is included as a part of the mine 
ventilation plan.
    MSHA is aware that through advances in technology it may be 
feasible to continuously monitor air quantity and velocity, and spray 
water flow rate and pressure. Continuous monitoring offers the 
potential to further improve miner protection by providing real-time 
data on the performance and condition of key dust control measures. 
This information can be used to give early warnings of deteriorating 
dust controls, allowing corrective action to be taken before the dust 
control system fails to protect miners from excessive dust levels. 
Although continuous monitoring will eliminate the need for periodic 
physical measurements to verify proper operation of some dust controls, 
visual observation of other controls will still be necessary. Among 
these are the number and location of operating water sprays, their 
general condition and orientation, the section ventilation setup and 
control device placement, the check for excessive leakage in the water 
delivery system, and other control measures where performance and 
operating condition can only be assessed visually.
    One commenter suggested that MSHA not permit the use of continuous 
monitoring in lieu of physical checks because technology to permit such 
monitoring is not as yet available. The final rule is intended to be 
sufficiently flexible to permit the use of new technology, such as 
continuous monitoring and sensing devices, and also to encourage the 
introduction of such modern equipment. The final rule does not require 
the physical measurement of the air velocity and quantity, water 
pressure and flow rates if continuous monitoring of the dust control 
parameters is used and indicates that the dust controls are functioning 
properly.
    The on-shift examination of the dust controls is to be completed 
under the direction of a person who has been designated by the 
operator. The proposal would have required that a certified person 
conduct the examination. One commenter objected to this approach, 
suggesting that the completion of this examination would require 
considerable time and that a more thorough examination could be 
accomplished by a person(s) familiar with the equipment and the dust 
control measures being utilized. This commenter recommended that MSHA 
remove the word ``certified'', thus permitting the examination to be 
conducted by persons other than certified persons. A second commenter 
argued that the examination should be conducted by a single individual 
because other persons may be assigned to a section who are not familiar 
with the requirements of the mine ventilation plan for that section.
    The final rule deletes the word ``certified,'' permitting on-shift 
examinations of dust controls to be conducted by one or more persons 
who are not certified individuals. However, the examination must still 
be conducted under the direction of a person designated by the operator 
and as set out in paragraph (g)(2), a certified person must certify 
that the examination has been completed. MSHA would expect that the 
person directing this examination would be present at the site of the 
examination while the examination is conducted.
    Another commenter recommended that the final rule not specify the 
measurements that are to be made need during the on-shift examination 
of dust controls, and that the standard be rewritten to require such an 
examination be sufficient to assure compliance with the respirable dust 
parameters specified in the mine ventilation plan. Because it is 
possible to identify specifically some of the parameters that must be 
measured in all instances the suggestion of the commenter has not been 
adopted. By identifying these parameters in the final rule, 
misunderstandings over whether a plan specification is for dust control 
or methane control, for example, can be eliminated.
    As proposed, paragraph (a)(2) would have required that the 
respirable dust control portion of the examination be made at or near 
the beginning of the shift and before production begins on a section. 
One commenter suggested that such a requirement would eliminate the 
common practice of changing shifts on the section without an 
interruption in production. MSHA recognizes that changing crews without 
an interruption in production has become a common practice in some 
areas and does not intend that this practice be changed by this rule. 
The final rule has revised the proposal so that when a shift change is 
accomplished without an interruption in production on a section, the 
required examination may be made any time within 1 hour of the shift 
change. In those instances when there is an interruption in production 
during a shift change, the final rule requires that the on-shift 
examination of respirable dust controls be made before production 
begins on a section. The proposed wording ``at or near the beginning of 
the shift'' has not been included in the final rule in recognition of 
the fact that production on a section could be delayed and not begun 
until well after the beginning of the shift. Because the purpose of the 
standard is to assure that dust exposures are controlled during mining, 
the on-shift examination must be conducted prior to the beginning of 
production in order to be most effective.
    Other commenters objected to examining respirable dust control 
parameters for various reasons. Some commenters stated that operators 
are 

[[Page 9800]]
required to comply with the requirements of the mine ventilation plan 
relative to dust control and a separate requirement is not needed. The 
measurements specified in the final rule are a practical way to provide 
reasonable assurance that miners are not being exposed to unhealthy 
levels of respirable dust. The purpose of these checks is not to 
restate the requirements for compliance with the mine's ventilation 
plan. Instead, as discussed above, the final rule is intended to bring 
needed attention to the proper functioning of dust controls before 
production begins.
    Other commenters expressed the opinion that coal production should 
not be delayed until after the completion of the examination of dust 
controls. According to these commenters, this examination will take the 
certified person away from other examinations that must be completed to 
assure safety. As explained previously, the final rule has been revised 
to permit the changing of crews without an interruption in production. 
The completion of the on-shift examination of dust control parameters 
can be postponed for up to 1 hour when crews are switched out at the 
face. Additionally, the final rule has been revised to permit the 
examination of dust control parameters to be performed by a person(s) 
other than a certified person and to simply require the certified 
person to certify that the examination was completed. These revisions 
substantially reduce any delay in production that could have resulted 
under the rule as proposed.
    Another commenter objected to the requirements of paragraph (a)(2) 
stating that examination of dust controls is unnecessary because all 
personnel are required to be trained in the requirements of all 
approved mine plans including the mine ventilation plan, and many of 
the required mine ventilation plan parameters are checked during the 
pre-shift examination. The commenter stated further that other 
parameters, such as number of water sprays and pressure, are checked by 
the equipment operators during the pre-operational inspection. In the 
opinion of the commenter, the proposed examination of dust control 
parameters is redundant and unnecessary.
    The requirements of paragraph (a)(2) are not redundant with 
existing standards. There is no requirement for a pre-operational 
inspection of dust controls. For the reasons discussed above, MSHA 
considers examination of dust controls for proper functioning to be an 
important practical measure for protecting miners'' health. To the 
extent that these checks are currently being made by some operators, 
together with the flexibility of the final rule, the burden of making 
these checks is minimized.
    The final rule requires in paragraph (a)(2) that deficiencies found 
during the on-shift examination of dust controls be corrected before 
production begins, or when crews are changed without an interruption in 
production, before production continues. The proposal would have 
required that deficiencies in the controls be corrected immediately. 
However, the final rule revises the proposal in response to one 
commenter who pointed out that the correction of deficiencies is 
important prior to production, in view of the purpose of the rule.
    Another commenter suggested that the examination of dust controls 
be conducted after production begins so as to be more representative of 
production conditions. In contrast, another commenter observed that if 
the required dust control parameters are not being met before 
production is begun, it is unlikely that they will be met after 
production is started. This commenter suggested multiple examinations, 
one before production begins and one at some later time during the 
shift. MSHA agrees that if dust control measures are deficient before 
production begins it is unlikely that they will be corrected later in 
the shift. Therefore the final rule requires the on-shift examination 
of the dust control measures prior to the beginning of production. The 
final rule, however, does not include the recommendation for an 
additional examination of dust control measures.
    Paragraphs (c)(1) and (c)(2) require certified persons conducting 
on-shift examinations to take air measurements at the same locations 
where air measurements are required during the preshift examination. 
This includes areas where mechanized mining equipment, including 
longwall or shortwall mining equipment, is being installed or removed. 
Reduced volume or velocity of air during the shift can contribute to 
increased levels of respirable dust, methane accumulations, or oxygen-
deficient atmospheres. Checking the mine's ventilation system verifies 
that changes in the mine ventilation system due to the production 
process have not occurred.
    The final rule removes the word ``working'' from paragraph (c)(1) 
to assure that the application of the standard would extend to all 
sections, consistent with paragraph (a). Many of the activities to 
which miners are assigned are on sections not normally thought of as 
``working sections,'' a term associated with coal production. For 
purposes of Sec. 75.362, a section in the mine is considered to be the 
area inby the loading point; or, in the case of the installation of 
mechanized mining equipment, inby the proposed loading point; or, in 
the case of the removal of mechanized mining equipment, inby the 
location of the last established loading point. The final rule requires 
in paragraphs (a)(1), (c)(1), and (c)(2) that the certified person 
conducting the on-shift examination examine the section in much the 
same way as it would be examined during a coal producing shift, 
including checking for hazardous conditions, testing for methane and 
oxygen deficiency, determining if the air is moving in its proper 
direction, and measuring the volume of air in the last open crosscut or 
in the intake of longwalls or shortwalls, as appropriate.
    Some commenters objected to this provision stating that there is 
little safety benefit to requiring on-shift examinations on sections 
other than working sections where coal is being produced. The final 
rule does not limit on-shift examinations to ``working sections'' but 
includes other areas where persons are working. Hazards similar to 
those that develop on a coal producing section can also develop during 
a shift on sections that are not producing, but where personnel are 
assigned to work.
    Paragraph (d)(1)(i) requires that at the start of each shift, 
before electrically operated equipment is energized, a qualified person 
test for methane at each working place. One commenter suggested that 
the existing standard is sufficient because quite often in today's 
mining practices equipment is already energized at the start of the 
shift since one equipment operator takes over from the previous 
operator and examinations for methane have been performed every 20 
minutes as required by Sec. 75.362(d)(1)(ii). MSHA does not agree that 
the existing standard is sufficient for a number of reasons. First, 
although the commenter is correct in stating that switching operators 
while the equipment remains energized is a relatively common practice 
it is not a universal practice. In mines where equipment is deenergized 
between shifts, the final rule provides for a test for methane in each 
working place prior to the equipment being energized. On sections in 
mines where equipment operators are switched while equipment remains 
energized, MSHA would consider a methane test performed during the 
previous 20 minutes under paragraph (d)(1)(iii) as sufficient to comply 
with the methane test requirement of paragraph (d)(1)(i) for the 
working place where mining is taking place. However, paragraph 

[[Page 9801]]
(d)(1)(i) also requires that methane tests be made in other working 
places on the section not only in the working place where the equipment 
is being operated.
    The final rule requires in paragraph (d)(1)(iii) that methane tests 
be made more frequently than 20 minutes if required in the approved 
mine ventilation plan at specific locations, during the operation of 
equipment in the working place. One commenter objected to this 
requirement expressing the opinion that the standard does not identify 
situations in which more frequent methane tests would be warranted and, 
therefore, operators could be faced with a requirement to conduct 
additional methane tests which are unwarranted and would result in the 
misallocation of safety resources. The final rule is intended to 
address situations such as an abnormally high methane liberation rate 
in a mine or an area of a mine that would warrant more frequent testing 
for methane. Like the existing standard the final rule requires this 
test to be made by a qualified person, not a certified person, thus in 
most cases the person who makes the test will be the machine operator. 
As a result, this test will not require that other safety-related 
activities be stopped to make a test for methane.
    Under the existing rule, methane tests required by paragraph (d)(1) 
were to be made at the last permanent roof support unless the mine 
ventilation plan required that they be made closer to the face using 
extendable probes. Paragraph (d)(2) of the final rule revises this 
standard and requires that the methane tests specified in paragraphs 
(d)(1)(i) through (d)(1)(iii) be made at the face from under permanent 
roof support, using extendable probes or other means. Like the existing 
standard, paragraph (d)(2) requires that for longwall and shortwall 
mining systems, the tests are to be made at the cutting head. When 
mining has been stopped for more than 20 minutes, methane tests must be 
made prior to the start up of the equipment.
    During informational meetings following the publishing of the 
existing standard, it became apparent that a large segment of the 
mining community felt that methane tests should be made as close to the 
working face as practicable without exposing miners to unsafe 
conditions. MSHA agrees that proper testing for methane at the face is 
essential for safe mining operations. The need for making methane tests 
at the face has been demonstrated by researchers and engineers from the 
U.S. Bureau of Mines and MSHA through work performed over the last 25 
years. This work documents that in a working place the concentrations 
near the face are considerably higher than other areas in the working 
place. For example, Luxner, in Bureau of Mines Report of Investigation 
7223, ``Face Ventilation in Underground Bituminous Coal Mines,'' 
published in 1969, reported methane concentration in excess of 5 
percent as far back as 15 feet using both blowing and exhaust 
ventilation systems with a curtain-to-face distance of 20 feet. The 
concentration outby this location as reported by Luxner was between 
zero and 1 percent. Later, Haney, et al., also showed lesser 
concentrations of methane further from the face using various types of 
assisted ventilation systems.
    A speaker at one of the public hearings on the proposal suggested 
that tests should be made at the last row of bolts and if 0.2 percent 
of methane is found at that location, a probe should be used to test at 
the face. The final rule does not adopt this recommendation because 
MSHA is unaware of any tests that relate the concentration of methane 
at the face with the concentration at the last row of bolts. Based on 
current knowledge, it is doubtful that such a direct correlation could 
be made because of the number of variables involved.
    A recurring comment concerning taking methane tests at the face 
with a probe was that such a requirement will lead to an increase in 
the number of back injuries among miners. However, other commenters 
supported the requirement and stated that probes as long as 40 feet are 
currently being used in some areas of the country. Miners with 
experience in using these probes testified at the rulemaking hearings 
that although the long probes can at times be difficult to use, they 
are being used and are providing measurements of methane at the face in 
mines operating in coal seams as low as 37 inches.
    The possibility of an increase in the number of back injuries is of 
serious concern to MSHA. However, after reviewing all of the written 
comments and testimony taken during public hearings, particularly that 
of miners having experience with the use of probes, MSHA is persuaded 
that this is a reasonable approach and will achieve the desired safety 
results without undue risk of back injuries.
    Several commenters suggested that in lieu of requiring methane 
tests at the face, MSHA should permit the use of the methane monitor to 
satisfy the requirement. In making this recommendation, one commenter 
suggested that the methane monitors should not be required to be 
installed on face equipment if they cannot also be used to test for 
methane in unsupported faces. Methane monitors have proven reliable 
over the years and provide a second level of protection against methane 
ignitions. Methane monitors provide for methane detection at a fixed 
location while the use of a methane detector with a probe permits 
methane measurements to be made at various locations in the face area.
    Historically, machine-mounted methane monitors have been used as a 
backup for the other required tests. This concept was exactly what 
Congress recognized in Sec. 303(l) of the Coal Mine Health and Safety 
Act of 1969 (Coal Act). Discussing this provision, the conference 
managers noted ``...the methane monitor is an additional backup device 
for detecting methane and should not be construed as a substitute for 
the other tests and testing devices required in this title for 
detecting and controlling methane.'' H.R. Conf. Rep. No. 91-761, 91st 
Cong., 1st Sess. 80 (1969).
    The final rule does not adopt the suggestion of commenters that 
methane monitors be accepted in lieu of the methane tests required by 
paragraph (d)(2).
    Paragraph (g)(1) adopts the language of proposed paragraph (g) and 
requires that the person making the on-shift examination in belt 
haulage entries certify by initials, date, and time that the 
examination was made at enough locations to show that the entire area 
has been examined. As explained in the preamble to the proposal, the 
existing rule does not require certification that examinations were 
conducted in belt conveyor entries. Comments received expressed the 
view that without certification, no mechanism exists to verify that 
examinations were conducted in belt conveyor entries. Other commenters 
questioned what MSHA meant by ``enough locations.'' MSHA agrees with 
the commenter that the certification requirement should be added to the 
rule to provide a means to verify that the examination has taken place. 
With respect to the locations where the certification should be made, 
this certification process is a common practice in the industry and is 
required by several state regulations. The locations where 
certification would be expected to be kept are no different than those 
which were required for many years under the previous MSHA regulation 
and which have been commonly accepted in the industry. Paragraph (g)(2) 
is a new requirement relating to the certification of the examination 
of respirable dust control parameters. Under (g)(2), the person making 
the on-shift examination to assure compliance with the respirable 

[[Page 9802]]
dust control parameters specified in the mine ventilation plan must 
certify by initials, date, and time that the examination was made.

Section 75.363 Hazardous Conditions; Posting, Correcting, and Recording

    Section 75.363 is a new section requiring the posting, correcting 
and recording of hazardous conditions. The posting of hazardous 
conditions against entry is a time tested method for preventing 
accidents. Examiners, upon finding a hazardous condition, erect 
``danger boards'' to alert persons traveling in the area of the 
presence of the hazard. In this manner, miners are prevented from 
inadvertently entering an area where a hazard exists. Section 75.363 
requires that hazardous conditions be posted and access to the area be 
limited; that the hazardous conditions be corrected immediately or 
remain posted; and, that a record be made and maintained of the 
hazardous condition and the action taken to correct the condition. 
Records of the hazards and the actions required to correct the hazards 
provide valuable safety information about conditions in the mine and 
the effectiveness of corrective measures.
    MSHA's final rule modifies the proposal in several ways. The final 
rule deletes the phrase ``or reported to'' that appeared in the first 
sentence of proposed Sec. 75.363(a) and deletes the requirement for 
countersigning by a second level official. It specifies that, except 
for preshift or preshift type examinations, hazardous conditions shall 
be corrected immediately or posted until the conditions are corrected. 
The final rule allows for countersigning by an official equivalent to 
the mine foreman and provides for storage of records in either a secure 
book or in electronic media which is not susceptible to alteration.
    It is essential that all hazardous conditions, regardless of when 
detected or by whom, be adequately addressed. Commenters suggested that 
the proposed standard be deleted because, in their opinion, other 
standards provide adequate coverage. One commenter interpreted the 
proposed standard as being directed at only those hazards found during 
the on-shift examination and supplemental examinations, because 
hazardous conditions found during the preshift and weekly are excluded 
from the standard. This commenter recommended rewriting the 
requirements for the on-shift and supplemental examinations to reflect 
the needed changes.
    Section 75.363 is not directed only toward hazardous conditions 
found during examinations. Hazardous conditions occur and are found at 
times during the shift when examinations are not being made. Under the 
final rule, these hazardous conditions would also require posting, 
correction, and recording when found by the mine foreman or equivalent 
mine official, assistants to the mine foreman or equivalent mine 
official, or other certified persons designated by the operator to 
conduct examinations.
    One commenter questioned whether the proposed standard was intended 
to assign new duties to the mine foreman and assistant mine foremen. 
The final rule does not impose additional responsibilities on the mine 
foreman and assistant mine foremen. However, these individuals are 
certified and routinely travel throughout the mine for purposes other 
than making examinations. The standard requires that hazardous 
conditions found by the mine foreman, assistant mine foreman, or 
equivalent mine officials, be treated the same as hazardous conditions 
found by other certified persons who have been designated to conduct 
examinations. That is, the hazardous conditions are to be appropriately 
posted, corrected, and recorded. The term ``equivalent mine officials'' 
has been added in response to commenters who suggested that the term 
``mine foreman'' is no longer used at all mines.
    Under paragraph (a) any hazardous condition found by the mine 
foreman or equivalent mine official, assistants to the mine foreman or 
equivalent mine official, or other certified persons designated by the 
operator to conduct examinations is to be posted with a conspicuous 
danger sign. The posting requirements of this section apply to every 
hazardous condition regardless of when it is found. Under the proposal, 
hazardous conditions reported to the mine foreman, assistants to the 
mine foreman or other certified persons designated by the operator to 
conduct examinations would have required posting. Commenters suggested 
that requiring hazardous conditions ``reported to'' these individuals 
would eliminate the judgement of the persons responsible for making 
decisions about whether or not a hazardous condition exists. One 
commenter suggested that the requirement, as proposed, could undermine 
the integrity of the certified person. The final rule is revised to 
require that hazardous conditions found by the mine foreman or 
equivalent mine official, assistant mine foreman or equivalent mine 
official, or other certified persons designated by the operator for the 
purpose of conducting examinations shall be posted with a conspicuous 
danger sign and shall be corrected immediately or remain posted. MSHA 
would expect that when a hazardous condition is reported to these 
certified persons, that the measures necessary to evaluate the 
situation and, if necessary, to comply with the provisions of this 
section would be taken.
    One commenter suggested that the proposed requirement that all 
hazardous conditions be corrected ``immediately'' would diminish safety 
because miners could be exposed to hazards unnecessarily. The commenter 
offered as an example an area of bad roof in a ``remote, unused 
crosscut'' and suggested that in this case posting of the area against 
entry would be sufficient. MSHA recognizes that there are instances, 
such as the example presented by the commenter, where safety is best 
served by simply posting the area against entry. This has long been the 
practice in the industry and the final rule does not prevent this from 
continuing. In these cases, the corrective action required to prevent 
injury is to preclude persons from entering the area. The proposal 
would have required that the hazardous condition be corrected 
immediately and that the area remain posted until the hazardous 
condition is corrected. To reflect the recommendation of the commenter, 
the final rule requires that the hazardous condition be corrected 
immediately or that the area remain posted until the hazardous 
condition is corrected. The Agency recognizes that in some instances 
posting the area against entry is the corrective action.
    The requirement that the hazardous conditions be corrected 
immediately does not necessarily require correction by the certified 
examiner finding the condition. To do so could delay the completion of 
the examination. Rather, the final rule requires that the hazardous 
condition be corrected following the reporting of the condition by the 
examiner to the appropriate mine official. Common sense and sound 
judgement should enter into the decisions as to when hazardous 
conditions are corrected. Posting of the area where the hazardous 
condition exists in order to prevent entry is to be accomplished by the 
certified person finding the hazardous condition.
    One commenter questioned whether proposed paragraph (a) would 
require the hazardous condition itself be posted. The posting of the 
area, as opposed to the hazardous condition itself, would, in most 
cases, be more effective and a safer practice. For instance, if a 
section 

[[Page 9803]]
of bad roof is detected, it would be in the best interest of safety to 
mark the area or perimeter of the area of bad roof instead of the roof 
itself. The ``danger'' sign would be placed at a location where anyone 
entering the area of the hazardous condition would pass so that persons 
approaching the area would be expected to see the ``danger'' sign. The 
area would remain posted until the hazardous conditions are corrected. 
The posting of areas where hazardous conditions exist to alert persons 
is a long-standing accepted safety practice in the mining community.
    Paragraph (a) requires that once an area is posted due to a 
hazardous condition, only persons designated by the operator to correct 
or evaluate the condition may enter the posted area. Additionally, if 
the hazardous condition creates an imminent danger, everyone must be 
withdrawn from the affected area to a safe area until the condition is 
corrected. Persons referred to in section 104(c) of the Act are 
permitted to enter in the area.
    One commenter suggested that the representative of the miners be 
permitted to enter an area which has been posted with a ``danger'' in 
order to evaluate the condition. The final rule follows the statutory 
provision in Sec. 104(c) of the Mine Act. This longstanding requirement 
provides that only persons designated by the operator to correct or 
evaluate the hazardous condition may enter such posted areas. With 
respect to the representative of miners, Sec. 104(c)(3) provides that 
the representative of the miners in such mine who is, in the judgment 
of the operator or an authorized representative of the Secretary, 
qualified to make mine examinations or who is accompanied by such a 
person and whose presence in such area is necessary for the 
investigation of the hazardous condition may enter the area.
    Paragraph (b) requires that a record of hazardous conditions be 
made by the end of the shift on which the condition was found. This 
record is required to be maintained on the surface and must include the 
nature and location of the hazardous condition and the corrective 
action taken. A record of all hazards found, as well as the required 
corrective action, serves as a history of the types of conditions that 
can be expected in the mine. When the records are properly completed 
and reviewed, mine management can use them to determine if the same 
hazardous conditions are recurring and if the corrective action being 
taken is effective. No record is required on any shift on which no 
hazardous conditions are found. Paragraph (b) excludes hazardous 
conditions found during the preshift and weekly examinations because 
these examinations have separate record keeping requirements.
    Commenters recommended rewording the standard to eliminate the 
provisions that no record is required on any shift on which no 
hazardous condition is found and that the corrective action taken must 
also be recorded. These suggestions were offered to clarify the 
standard. MSHA believes that deleting these requirements would not 
clarify the rule and the suggestions are not adopted in the final rule.
    Paragraph (c) requires that a record be made either by the 
certified person who conducted the examination or by a person 
designated by the operator. As with other records required by this 
subpart, when the record is made by a designated person other than the 
certified person making the examination, the person making the record 
need not be certified. If the record is made by a person designated by 
the operator, the certified person must verify the record by initials 
and date. MSHA did not receive any comments objecting to this part of 
the standard. Like the other recordkeeping requirements in the 
proposal, proposed paragraph (c) would have required that the record be 
made in a state-approved book or a bound book with sequential machine-
numbered pages. Additionally, the proposal would have required 
countersigning by both the mine foreman and the superintendent or 
equivalent individual to whom the mine foreman reports. The final rule 
requires that the records of hazardous conditions must be kept in 
either secure books that are not susceptible to alteration, or 
electronically in a computer system so as to be secure and not 
susceptible to alteration. A detailed discussion of record books and 
the use of computers to maintain records can be found in the General 
Discussion of this preamble.
    A variety of comments were received regarding the countersigning of 
the record by the mine foreman, and the time permitted for 
countersigning. The final rule adopts the proposal that the mine 
foreman or equivalent mine official must countersign the record of 
hazardous conditions by the end of the mine foreman's next regularly 
scheduled working shift. The mine foreman is responsible for the day-
to-day operation of the mine. It is essential for the health and safety 
of the miners that the mine foreman be fully aware of the information 
contained in this record so as to be able to allocate resources to 
correct safety problems as they develop. Allowing until the end of the 
mine foreman's next regularly scheduled working shift to countersign 
the records assures that the mine foreman is aware of hazardous 
conditions in sufficient time to initiate corrective actions.
    Some commenters suggested that the time for countersigning is 
unnecessarily long, and that the final rule should require daily 
countersigning by the mine foreman. The rulemaking record does not 
show, however, that the time set by the final rule would expose miners 
to safety or health risks. Also, hazardous conditions must be corrected 
immediately or the area must remain posted until the condition is 
corrected.
    Numerous comments were received regarding the requirement of the 
proposal for second level countersigning of the preshift examination 
record by the mine superintendent, mine manager, or other mine official 
to whom the mine foreman is directly accountable within 2 scheduled 
production days after the countersigning by the mine foreman. The final 
rule does not retain this proposed requirement. A detailed discussion 
of the subject of second level countersigning can be found in the 
General Discussion section of this preamble.
    As proposed, paragraph (d) of the final rule requires that the 
records required by Sec. 75.363 be maintained at a surface location at 
the mine for one year and be made available for inspection by 
authorized representatives of the Secretary and the representative of 
miners. Comments on this requirement were generally favorable. A 
discussion of comments concerning the use of computers to maintain 
records can be found in the General Discussion of this preamble.

Section 75.364 Weekly Examination

    The weekly examination is directed at hazards that develop in the 
more remote and less frequently visited areas of a mine. These areas 
include: worked-out areas where pillars have not been removed, bleeder 
entries used to ventilate worked-out areas where pillars have been 
removed and, some main intake and return air courses. Over the course 
of time, hazards such as methane accumulations and obstructions to 
ventilation can develop in these areas and can result in an explosion 
or loss of ventilation if not discovered and corrected. Because of the 
confined nature of the underground mining environment, loss of life can 
result in other areas of the mine outside the immediate location of the 
hazard. The weekly examination assures that these hazards are located 
and corrected.
    Generally, Sec. 75.364 requires an examination in unsealed worked-
out areas that have not been pillared; travel 

[[Page 9804]]
in bleeder entries and the performance of appropriate measurements in 
these entries and; a check for hazardous conditions in return and 
intake air courses, in each longwall travelway, at each seal along 
return and bleeder air courses and each seal along intake air courses 
not otherwise examined, in each escapeway, and each working section 
that has not been preshift examined during the previous 7 days.
    The final rule modifies existing Sec. 75.364 (a), (b), and (h). It 
adopts several proposed changes to Sec. 75.364 and modifies or rejects 
other proposed changes.
    Paragraph (a) specifies weekly examination requirements in unsealed 
worked-out areas where no pillars have been recovered as well as in 
bleeder systems. The final rule requires that unpillared worked-out 
areas and bleeder systems be physically examined on a weekly basis and 
specifies the tests and measurements to be performed by the examiner. 
The final rule identifies two separate locations within nonpillared 
areas and bleeder systems where measurements may be required. First, 
measurement points must be included in the mine ventilation plan to 
identify the locations within unpillared worked-out areas and bleeder 
systems where examiners will conduct air measurements and tests, the 
results of which are to be recorded. These measurement points are not 
in lieu of traveling the system, but rather are the locations where the 
examiner will perform air quantity and quality tests and measurements 
to determine the effectiveness of ventilation. These points are 
tracking and evaluation tools to assure adequate ventilation and to 
identify developing trends in ventilation or air quality which may 
require attention.
    Second, evaluation points may be approved in the mine ventilation 
plan on a case-by-case basis as provided under (a)(1) and by 
(a)(2)(iv). These evaluation points may be used in lieu of physical 
examinations. Evaluation points may only be approved in lieu of travel 
if the evaluation points are fully adequate to demonstrate that the 
area is ventilated. These provisions are discussed below.
    The final rule clarifies that measurement points for weekly 
examinations must be specified in the mine ventilation plan for both 
unpillared and pillared worked-out areas described in (a)(1) and 
(a)(2)(iii), respectively. These measurement points are distinct from 
the evaluation points which may be approved in lieu of a physical 
examination under some circumstances. As mentioned above, evaluation 
points are governed by (a)(1) for unpillared worked-out areas, and by 
(a)(2)(iv) for pillared worked-out areas ventilated by bleeder systems. 
Section 75.371(z) of the final rule refers to these requirements for 
both measurement points and evaluation points. The measurement points 
and evaluation points may be either in the body of the mine ventilation 
plan or may be shown on the 75.372 map. In either case, the locations 
are subject to approval by MSHA.
    Under paragraph (a)(1), at least every 7 days a certified person 
must examine unsealed worked-out areas where no pillars have been 
recovered by traveling to the area of deepest penetration; measuring 
methane and oxygen concentrations and air quantities and making tests 
to determine if the air is moving in its proper direction in the areas. 
The locations of measurement points where tests and measurements will 
be performed must be included in the mine ventilation plan and must be 
adequate in number and location to assure ventilation and air quality 
in the area. Air quantity measurements must be made where the air 
enters and leaves the worked-out areas. Sufficient methane and oxygen 
measurements must be made to assure the air quality in the worked-out 
areas. An alternative method of evaluating the ventilation of the areas 
may be approved in the mine ventilation plan.
    Under paragraph (a)(1), in addition to measuring oxygen and methane 
concentrations and testing for proper air direction, air quantities 
must also be determined. Air quantity measurements are required where 
air enters and leaves the worked-out area. The final rule also requires 
that a sufficient number of measurement points must be included in the 
mine ventilation plan to assure appropriate ventilation and air quality 
in the area.
    The changes to paragraph (a)(1) are in response to comments and 
MSHA experience with weekly examinations. Currently some examiners are 
simply traveling to the point of deepest penetration while conducting 
few if any tests or air measurements within the system. The full 
benefit of an examiner traveling to the point of deepest penetration is 
lost if the examiner does not conduct air quantity and quality 
measurements at key locations.
    The results of these measurements are important in assessing the 
effectiveness of ventilation. In addition, trends in either air 
quantity or quality can reveal developing problems which can be 
corrected in the earliest stages.
    One commenter suggested that the entire perimeter of worked-out 
areas should be physically examined to all points of deepest 
penetration. The commenter suggested that the face of each entry or 
room should be examined at its point of deepest penetration. MSHA 
agrees that travel to a single point of deepest penetration within an 
area may sometimes be inadequate to fully demonstrate effective 
ventilation of a worked-out area. The final rule addresses this issue 
by requiring that measurement points be established in the mine 
ventilation plan.
    Paragraphs (a)(2) (i) through (iv) of the final rule retain the 
requirement that at least every 7 days a certified person must evaluate 
the effectiveness of bleeder systems used under Sec. 75.334 (b) and 
(c). Like the proposal, the final rule also specifies tests and 
locations for an effective examination. One commenter noted that mine 
examinations are sometimes ineffective and supported the proposed 
additional specificity in the rule, requiring air measurements and 
tests at key locations or measurement points within worked-out areas. 
Established locations where examiners will conduct air measurement and 
tests will help assure effective examinations and provide quantitative 
results to the operator. The final rule requires that the mine 
ventilation plan include measurement points within worked-out areas and 
paragraph (h) requires that the results be recorded.
    Paragraph (a)(2)(ii) requires that measurements of methane and 
oxygen concentrations be made, air quantity be measured, and a test 
performed to determine if the air is moving in its proper direction at 
a point immediately before the air enters a return split of air. A 
commenter supported the proposed air measurements where air enters and 
leaves worked-out areas and correctly noted that such measurements 
would reveal some types of ventilation problems. In a special case, 
such as where it may not be possible to measure intake air, paragraph 
(a)(2)(iv) permits an alternate method of evaluation to be used when 
approved in the mine's ventilation plan.
    Another potential hazard exists when multiple intake openings lead 
into such an area, if passing intake air enters upstream openings of 
the worked-out area and reenters the intake from downstream openings. 
The final rule also requires that air quantity measurements be made 
where air enters and leaves worked-out areas. Measurements made where 
air enters and exits the area will alert the examiner and operator to 
airflow changes or imbalances which indicate a potentially dangerous 
ventilation problem. The specification of 

[[Page 9805]]
measurement points within worked-out areas will also assure that short 
circuits have not interrupted ventilation.
    One commenter stated that the standard should fully delineate all 
aspects of the weekly examination by specifying that the examination 
include roof and ribs, ventilation controls, water accumulations, etc. 
Although MSHA agrees that these and other conditions fall within the 
purview of the weekly examination, the final rule does not attempt to 
provide an exhaustive list of what is to be covered in a weekly 
examination. Examinations are performed by persons trained and 
certified as able to make the required examinations. Such certified 
persons can be expected to give proper attention to basic safety 
considerations.
    Paragraph (a)(2)(iii) requires that at least one entry of each set 
of bleeder entries used as part of a bleeder system under Sec. 75.334 
must be traveled in its entirety. Under the final rule, measurements of 
methane and oxygen concentrations and air quantities are required to be 
made during the examination. Also, a test to determine if the air is 
moving in its proper direction must be made at locations or measurement 
points, specified in the mine's ventilation plan. The measurements and 
tests provide the information necessary to determine the effectiveness 
of the bleeder system.
    One commenter believed that the proposal would require each 
parallel and common bleeder entry of a set to be traveled. The final 
rule is intended to simplify the examination and would, under the 
circumstances described by the commenter, require only one entry of a 
set of common entries to be examined in a bleeder system. Also, similar 
to the requirements for traveling intake and return air courses, this 
requirement should not be interpreted to require the examiner to stay 
in one entry. For example, if the examiner desires to ``zig zag'' 
between entries while traveling in a multi-entry bleeder system, this 
would be acceptable under the regulation provided tests and 
measurements are made at the appropriate locations.
    Paragraph (a)(2)(iv) provides that, in lieu of the requirements of 
(i) through (iii), alternative methods of evaluation may be specified 
in the mine ventilation plan provided that the alternative method 
results in proper evaluation of the effectiveness of the bleeder 
system. One commenter cited several explosions that were related to 
bleeder system deficiencies and linked poor design and inadequate 
maintenance with the provision allowing examination at evaluation 
points in lieu of traveling the area in its entirety. The thrust of the 
commenter's argument was that an inflexible standard requiring either 
full travel of a bleeder system or sealing of the entire area would 
result in superior designs and improved maintenance. While MSHA agrees 
with the commenter's ultimate objective of ensuring effective 
ventilation of bleeder systems and worked-out areas, MSHA does not 
agree that elimination of any flexibility within the standard would 
result in infallible designs. Since approval of evaluation points is 
only granted in cases where adequate ventilation can be determined 
through evaluation, MSHA believes that retaining flexibility to review 
individual cases is an appropriate method and results in proper 
evaluation of the effectiveness of the bleeder system.
    Paragraph (h) of the final rule governs recordkeeping requirements 
for weekly examinations. The final rule incorporates several revisions 
based on recommendations submitted by commenters. The final rule 
requires that at the completion of any shift during which a portion of 
a weekly examination is conducted, a record of the results be made. 
This record must include any hazardous conditions found during the 
examination and their locations, the corrective actions taken, and the 
results and location of air and methane measurements. The record must 
be made by the person making the weekly examination or a person 
designated by the operator.
    The final rule includes a revision requiring that the results of 
methane tests must be recorded as the percentage of methane measured by 
the examiner. Previously, terms such as ``ok,'' ``low,'' or ``trace'' 
were entered in record books as test results. The final rule clarifies 
that such qualitative terms are not acceptable when examination 
requirements specify the measurement of air quantity or methane levels 
as such entries provide little useful information.
    The final rule requires that if the record is made by a person 
other than the examiner, the examiner must verify the record by 
initials and date by or at the end of the shift for which the 
examination was made. As with other records required by this rule, the 
records of weekly examinations may be kept either in secure books that 
are not susceptible to alteration, or electronically in a computer 
system so as to be secure and not susceptible to alteration. A detailed 
discussion of record books and the use of computers to maintain records 
can be found in the General Discussion of this preamble.
    Commenters suggested that the final rule only require the examiner 
to record uncorrected hazardous conditions. MSHA is sensitive to 
minimizing recordkeeping requirements and, for example, the final rule 
requires only uncorrected defects found during the fan examination to 
be recorded. However, the weekly examination record serves as a history 
of the types of conditions that can be expected in the mine. When the 
records are properly completed and reviewed, management can use them to 
determine if the same hazardous conditions are occurring and if the 
corrective action being taken is effective. Additionally, this record 
can permit mine management, the representative of the Secretary, and 
the representative of miners to better focus their attention during 
examinations and inspections. The final rule adopts the proposal and 
requires the examiner to record all hazardous conditions found and the 
action taken to correct the hazardous condition.
    A variety of comments were received regarding the countersigning of 
the records of weekly examinations by the mine foreman, and the time 
permitted for countersigning. The final rule adopts the proposal that 
the mine foreman or equivalent mine official must countersign the 
record of the weekly examination by the end of the mine foreman's next 
regularly scheduled working shift. The mine foreman is in a key 
position of responsibility relative to the day-to-day operation of the 
mine. It is essential for the health and safety of the miners that the 
mine foreman be fully aware of the information contained in the 
preshift examination reports so as to be able to allocate resources to 
correct safety problems as they develop. Allowing until the end of the 
mine foreman's next regularly scheduled working shift to countersign 
the reports assures that the mine foreman is aware of the results on a 
regular and timely basis.
    Numerous comments were received regarding the requirement of the 
proposal for second level countersigning of the weekly examination 
record by the mine superintendent, mine manager, or other mine official 
to whom the mine foreman is directly accountable. A full discussion of 
second level countersigning can be found in the General Discussion 
section of this preamble.
    Paragraph (h) of the final rule also contains revisions to the 
existing rule to allow for electronic storage of records. Paragraph (i) 
requires that the records required by Sec. 75.364 be maintained at a 
surface location at the mine for one year and be made available for 
inspection by authorized representatives of the Secretary and the 
representatives of 

[[Page 9806]]
miners. A discussion of comments concerning the use of computers to 
maintain records can be found in the General Discussion of this 
preamble.
    Under the final rule, the record of weekly examinations must be 
countersigned by the mine foreman or equivalent mine official by the 
end of the mine foreman's next regularly scheduled working shift. Based 
on comments noting that traditional mine management structures have 
changes at some operations, the final rule provides that an official 
equivalent to mine foreman may countersign the records. The purpose of 
this change is to require that when a mine foreman is not present in 
the mine's management structure, an equivalent official must perform 
this function. As with the existing standard, second level 
countersigning by the mine superintendent is not required by the final 
rule.
    The record of weekly examinations must be made in secure media not 
susceptible to alteration. If records are made electronically, they 
must be unalterable, shall capture dates and signatures, must be 
accessible to representatives of the miners and the Secretary, and must 
be capable of producing printouts. Further discussion of both the 
issues of second level countersigning and acceptable record books or 
electronic records can be found in the general discussion section of 
this preamble.
    The proposal, at paragraph (b), would have added a requirement that 
the certified person examine for noncompliance with mandatory safety or 
health standards that could result in a hazardous condition. The 
proposal drew considerable objection. Commenters objected to the 
unlimited scope of the term ``noncompliance,'' the legal propriety of 
recording noncompliance, and the additional examination time required 
to determine noncompliance, the diversion of the examiner's attention 
away from key safety conditions to minor compliance issues. Even so, 
another commenter supported the proposal as necessary, suggesting that 
the earlier rule was intended to require operators to assure full 
compliance through the required examinations. The commenter correctly 
noted that a requirement to examine for safety and health violations 
was in effect from 1970 until 1992 when it was deleted.
    While the proposed standard appeared attractive in concept, the 
majority of comments received indicate that the standard would result 
in considerable confusion. In addition, it would be impractical to 
define and adequately limit the scope of the requirement. Comments 
consistently indicated confusion and misinterpretation of the 
proposal's scope, offering a wide range of interpretations.
    As discussed in the preamble to the 1992 rule, most hazards are 
violations of mandatory standards. Requiring the examiner to look for 
all violations regardless of whether they involve a distinct hazard 
could distract the examiner from the more important aspects of the 
examination. Despite an attempt in the proposal to limit the scope of 
the examination for noncompliance to situations that, ``could result in 
a hazardous condition,'' commenters expressed a high level of 
misunderstanding. Although a similar requirement existed between 1970 
and 1992, MSHA generally did not broadly apply the standard. After 
consideration of all comments and a review of the history since the 
current standard became effective, MSHA concludes that the existing 
standard is appropriate and best serves the objective of giving 
examiners clear guidance for making effective examinations. 
Accordingly, the proposal for examinations to include noncompliance 
with mandatory safety and health standards is not adopted in the final 
rule.
    Paragraph (b)(7) has been added to require that water pumps not 
examined as part of a preshift examination conducted during the 
previous 7 days be examined during the weekly examination. This 
modification is an outgrowth of comments received in response to 
proposed Sec. 75.360, which would have required examination of certain 
pumps. As discussed in the preamble to Sec. 75.360, one commenter 
persuasively argued that all pumps should be examined. Pumps that are 
not preshift examined under the final rule are generally located in 
remote areas of the mine. These pumps are appropriately examined on a 
weekly basis.

Section 75.371 Mine Ventilation Plan; Contents

    Section 75.371 sets forth the information that the operator must 
include in the mine ventilation plan. Because the plan deals with 
situations 

[[Page 9809]]
unique to a mine, the general rules applicable in other standards do 
not fit. For the convenience of the reader, the standard that sets out 
the general rule or provides for an option to include a provision in a 
plan will generally cross reference to the appropriate paragraph in 
Sec. 75.371.
    MSHA proposed revisions to existing paragraphs (b), (s), (z) and 
(bb) of Sec. 75.371 and reproposed existing paragraph (r). MSHA's final 
rule adopts the proposal for paragraphs (s), (z) and (bb). MSHA revises 
its proposed paragraph (r) to make conforming changes with other 
provisions. Finally, the final rule retains the existing language for 
paragraph (b).
    As stated in the General Discussion section of this preamble, 
provisions concerning the installation and removal of mechanized mining 
equipment that were promulgated in May of 1992 as part of the safety 
standards for underground coal mine ventilation were reproposed in May 
of 1994 as part of this rulemaking for the purpose of receiving and 
giving full consideration to all pertinent comments on this issue. 
Paragraph (r) of the final rule is one of the provisions that was 
reproposed. Section 75.325(d) of the final rule requires that areas 
where mechanized mining equipment, including longwall equipment, is 
being installed and removed be ventilated. Paragraph (r) of Sec. 75.371 
requires that the quantity of air that will be provided be included in 
the mine ventilation plan. Most commenters either supported the 
provision, citing the explosion at the William Station Mine, or stated 
that the standard was originally promulgated inappropriately and did 
not substantively comment on the requirement. One commenter suggested 
that the quantity of air specified in the plan under paragraph (r) 
should represent the minimum quantity that will be provided and the 
location specified should be identified as what would be typical so as 
to give the mine the flexibility to adapt to varying mine conditions. 
This recommendation is consistent with MSHA's intent and MSHA has 
included it in the final rule to help clarify the rule.
    One commenter suggested that the ventilation scheme shown in the 
plan should be representative of the method of ventilation to be used. 
MSHA agrees that the mine ventilation plan should include a method of 
ventilation that is representative of that used in the mine. However, 
MSHA has not adopted this suggestion since the plan must be specific 
enough so that the operator, the miners, the representative of miners, 
and MSHA are assured that all areas are being adequately ventilated.
    Paragraph (r) of the final rule requires that the mine ventilation 
plan include the location where air quantities will be provided, and 
the ventilation controls that will be used to provide these quantities. 
This language was included in the reproposed provision and in 
Sec. 75.325(d), which requires that the quantity of air that will be 
provided during the installation and removal of mechanized mining 
equipment, the location where this quantity will be provided, and the 
ventilation controls that will be used, be included in the mine 
ventilation plan. In reproposing paragraph (r), MSHA inadvertently 
excluded from Sec. 75.371(r) the requirement relative to the location 
where the air quantity is provided. The final rule has been modified in 
Sec. 75.371(r) to conform to the requirements of Sec. 75.325(d).
    The final rule revises existing paragraph (s) to conform to changes 
in Sec. 75.362(d)(1)(iii). The final rule deletes the portion of 
existing Sec. 75.362(d)(2) which requires that the mine ventilation 
plan include the location of tests which are to be made closer to the 
working face than the last permanent roof supports using extendable 
probes or other acceptable means. The final rule in paragraph 
(d)(1)(iii) requires that the mine ventilation plan specify the 
frequency and location of the methane tests if required more often than 
20 minutes by Sec. 75.362(d)(1)(iii). One commenter suggested adding 
the words, ``or at other locations and frequencies if approved by the 
district manager and contained in the ventilation plan.'' The suggested 
clarification is not necessary and has not been adopted in the final 
rule.
    The final rule revises paragraph (z) to conform to Sec. 75.364(a). 
Section 75.364(a) addresses the measurements to be made to evaluate the 
effectiveness of bleeder systems and the ventilation of worked-out 
areas during the weekly examination. The final rule requires that the 
locations where these measurements are made or alternative methods of 
providing these evaluations be included in the mine ventilation plan. 
One commenter suggested that the locations where air measurements are 
made should not be required in the mine ventilation plan. The commenter 
made a similar suggestion relative to the requirement in Sec. 75.364 
that air measurements be made to evaluate the ventilation of worked-out 
areas and determine the effectiveness of bleeder systems. According to 
the commenter, since no specific air volume is required it is not 
necessary to measure the volume present. The measurement of air 
quantity, as well as the other measurements required by the existing 
standard, are essential to evaluate the ventilation of worked-out areas 
and determine the effectiveness of bleeder systems. The final rule, 
therefore, does not include the suggested changes in either Sec. 75.364 
or Sec. 75.371(z).
    Another commenter suggested that since the current standards do not 
require a specific volume of air in bleeder entries, it is unnecessary 
to measure the air volume. Proper evaluation of the effectiveness of a 
bleeder system can only be achieved by comparison of measurements taken 
in the bleeder system. In most instances, one of the most important 
measurements is the air quantity at strategic points in the bleeder 
system. Therefore, the final rule includes the proposed requirement 
that the locations where air quantity measurements will be made in the 
bleeder system be specified in the mine ventilation plan.
    Existing paragraph (bb) requires that the location of ventilating 
devices used to control air movement through worked-out areas be 
included in the mine ventilation plan. The final rule reinstates a 
requirement contained in the previous regulation, that the location and 
sequence of construction of proposed seals also be indicated. This 
requirement is consistent with Sec. 75.334(e) which requires that the 
sequence of construction of seals be specified in the mine ventilation 
plan. Some commenters on paragraph (bb) and Sec. 75.334(e) suggested 
that proper sequencing of seals can change due to mining conditions and 
should not be made a part of the mine ventilation plan. Another 
commenter suggested that because the time to get a plan approved can be 
lengthy, it may even create unnecessary hazards. Proper sequencing of 
seal construction is necessary for effective ventilation during 
sealing. Therefore, the final rule requires the location and sequence 
of the construction of seals be specified and approved in the mine 
ventilation plan. If a delay in seal construction will result in a 
hazard to miners, the review and approval of the plan can be expedited 
as explained in the preamble discussion of Sec. 75.370.
    One commenter on paragraph (bb) suggested that the locations of 
stoppings, regulators, and bleeder connector entries are better shown 
on the mine map with a notation that it is subject to approval under 
Sec. 75.371. The existing standard permits appropriate information 
required under Sec. 75.371 to be shown on the map required by 
Sec. 75.372. This is explained in the preamble discussion for existing 
Sec. 75.371. MSHA recognizes that some of 

[[Page 9810]]
the information required to be submitted under Sec. 75.371 is best 
shown on a map. Rather than require additional maps, this information 
may be shown on the Sec. 75.372 map. When shown on the Sec. 75.372 map, 
only that portion of the map that contains information required under 
Sec. 75.371 is subject to approval by the district manager.
    The proposal would have revised paragraph (b) to reflect the 
proposed changes in paragraphs (c) and (d) of Sec. 75.312 allowing 
alternative testing methods for main mine fan automatic closing doors 
and fan signals. Because the final rule does not include the proposed 
changes to Sec. 75.312(c) and (d), final rule Sec. 75.371(b) conforms.

Section 75.372 Mine Ventilation Map

    The mine ventilation map provides a basis for understanding how a 
particular coal mine is ventilated. An accurate and up to date map of 
the mine enables the operator and MSHA to review the mine's ventilation 
plan to determine the appropriateness of the ventilation system to the 
conditions in the mine. Only through a thorough understanding of the 
ventilation system can the operator and others determine whether the 
system is capable of preventing methane accumulations, possible 
explosions, and high levels of respirable dust. Generally, Sec. 75.372 
requires that the necessary information be provided on the map.
    The final rule revises existing paragraph (b)(3) and adds new 
paragraphs (b)(19) and (b)(20). Paragraph (b)(3) addresses which 
adjacent workings must be shown on the mine map. The final rule, like 
the proposal, requires all known adjacent workings within 1,000 feet of 
existing or projected mine workings to be shown on the mine map, 
regardless of whether the workings are located on mine property or on 
adjacent property. The existing rule required that only the adjacent 
workings within 1,000 feet be shown if they are on mine property.
    MSHA has concluded that it is necessary to require that the mine 
ventilation map include all known workings located in the same coalbed 
within 1,000 feet of existing or projected workings, regardless of 
whether the workings are located on the mine property. Hazards, such as 
methane and water accumulations and irrespirable atmospheres, exist in 
old workings whether located on mine property or not. MSHA also notes 
that this revision makes paragraph (b)(3) consistent with existing 
paragraph (h) of Sec. 75.1200, Mine map. Paragraph (h) of Sec. 75.1200 
requires that the mine map show all adjacent mine workings within 1,000 
feet. Like the previous standard, this revision would assure that all 
adjacent mine workings appear on the Sec. 75.372 map in those cases 
where operators do not use a Sec. 75.1200 map for their required 
submission.
    One commenter suggested that this requirement not be included 
because mine operators have no legal obligation or authority to force 
an adjacent land owner to provide the required information. MSHA 
recognizes that the mine operator may, in some instances, have 
difficulty obtaining this information. The hazards that exist within 
abandoned mines, however, warrant such a requirement. Additionally, as 
noted previously, this requirement is consistent with the requirements 
of Sec. 75.1200(h) and will, therefore, impose no additional burden on 
the operator. Agency experience reveals that the existing standard, 
Sec. 75.1200(h), has not proven to be practically difficult for 
compliance. In addition, this information would be available to the 
miners and would enhance their understanding of the ventilation system 
and aid them in the event of an emergency.
    Another commenter suggested that the rule explicitly require that 
all mine workings, including workings from auger mining, highwall 
mining and strip mining, be shown on the map. This recommendation has 
not been included in the final rule because MSHA believes that the 
final rule is clear and requires any workings from other mines, such as 
strip, auger and similar workings, to be shown if they are in the same 
coalbed and are within 1,000 feet of existing or projected mine 
workings.
    Proposed paragraph (b)(19) is adopted in the final rule. The 
proposal was drafted in response to comments received at public 
meetings. It reinstates the requirement in the previous standard that 
the mine map include the entry height, velocity and direction of the 
air current at or near the midpoint of each belt flight where the 
height and width of the entry are representative of the belt haulage 
entry. Paragraph (b)(19) of the final rule should assist the examiner 
in rapidly determining whether the air is flowing in its normal 
velocity and direction during examination of the belt entry required 
elsewhere in subpart D. One commenter suggested that this requirement 
is redundant because the mine ventilation plan already requires that 
this be ``illustrated''. MSHA does not agree that the requirement is 
redundant since there is no such requirement in the mine ventilation 
plan.
    MSHA emphasizes that like much of the information required to be 
shown on the ventilation map, this information would not be subject to 
approval. When shown on the Sec. 75.372 map, only that portion of the 
map that contains information required under Sec. 75.371 is subject to 
approval by the district manager. The information required by paragraph 
(b)(19) does not fit this criteria and therefore is not subject to 
approval by the district manager.
    As explained in the discussion of Sec. 75.301, instances have 
developed where operators direct air from an intake air course to 
ventilate shops, electrical installations, or for other purposes, and 
this air is then coursed to the surface and is not used to ventilate 
working places. Under one interpretation of the existing definition, 
because this air has not ventilated a working place or a worked-out 
area, the air course cannot be considered a return air course. In these 
instances, the final rule in Sec. 75.301 expressly permits the 
redesignation of the affected portion of the air course as a return air 
course. Because it is important that personnel, including examiners, 
the miners' representative, and representatives of the Secretary, know 
which air courses have been redesignated, the final rule requires that 
these air courses be shown on the map. Paragraph (b)(20) requires that 
the location of redesignated air courses be shown on the ventilation 
map. Commenters were supportive of this provision.

Section 75.380 Escapeways; Bituminous and Lignite Mines

    When a fire, explosion or other emergency necessitates an immediate 
evacuation of a mine, the designated route for miners to leave the mine 
is the escapeway. The escapeway should be appropriately located and 
designed to be free of obstructions and hazards to assure safe passage 
from the hazardous underground environment. The final rule addresses 
requirements for escapeways. Paragraphs (b)(1) and (b)(2) set forth the 
requirements for the location of the escapeway when installing and 
removing mechanized mining equipment. Paragraphs (d)(3) through (d)(5) 
deal with the minimum dimensions of escapeways. Paragraph (f) addresses 
the equipment that can be used in escapeways and the requirements for 
fire suppression systems on this equipment. Finally, paragraph (i) sets 
the minimum slope of an escapeway.
    The final rule republishes existing paragraphs (b)(1) and (b)(2) 
and revises paragraph (d)(3) through (d)(5), (f) and (i)(2).
    Sections 75.380 (b)(1) and (b)(2) of the final rule deal with 
escapeways on 

[[Page 9811]]
working sections and areas where mechanized mining equipment is being 
installed or removed. MSHA adopts the proposal in the final rule. An 
in-depth discussion of the proposal of provisions concerning the 
installation and removal of mechanized mining equipment is presented in 
the General Discussion section of this preamble.
    MSHA specifically solicited comments on those portions of the 
proposal dealing with the installation and removal of mechanized mining 
equipment, including paragraphs (b)(1) and (b)(2) of Sec. 75.380. These 
paragraphs require that an escapeway be provided to areas where 
mechanized mining equipment is being installed or removed. Only one 
substantive comment was received. The commenter suggested that the 
location of the beginning of the escapeway during equipment 
installation and removal should be specified in the mine ventilation 
plan to minimize the potential for congestion during movement of heavy 
equipment. The commenter stated that the proposal would eliminate all 
access to a longwall during the installation or removal of the longwall 
equipment except for the face crosscut, and lead to accidents.
    MSHA believes that the location where the loading point will be 
installed and where the loading point was last located prior to removal 
are easily identifiable and offer the best choice. The suggestion of 
the commenter has not been adopted in the final rule. In addition, the 
commenter noted that mobile equipment was needed during the 
installation and removal of longwalls; this equipment can be used in 
the escapeway if properly attended and protected with proper fire 
suppression.
    As with the existing rule, paragraph (d)(3) of the final rule 
generally requires escapeways to be maintained to a height of 5 feet 
from the mine floor to the mine roof, excluding the thickness of any 
roof support. To accommodate mines in low seams, the rule provides that 
where the coalbed is less than 5 feet, the escapeways shall be 
maintained at least to the height of the coalbed. As in the past, 
convergence, the reduction in entry height due to roof sag or floor 
heave, which occurs as a natural geologic process, will be excluded 
when determining escapeway height unless it would impede the escape of 
miners, including disabled persons, in the event of an emergency. The 
final rule modifies (d)(3) to provide that in areas of mines where 
escapeways pass through doors or in areas of mines developed before 
November 16, 1992 where escapeways pass across or under overcasts or 
undercasts, the height of the escapeway may be less than 5 feet 
provided the height is sufficient to enable miners, including disabled 
persons, to escape quickly in an emergency. It was brought to the 
attention of MSHA by one commenter that in some instances the removal 
of roof support or the lowering of the tops of overcasts may be 
necessary to provide the 5-foot height required by the existing rule. 
It has been suggested that this could result in a diminution of safety.
    One commenter suggested that escapeways should be 6 feet in width 
and 5 feet in height without exception. This suggestion has not been 
adopted in the final rule. Under the previous rule, escapeway 
dimensions were addressed through criteria and operators routinely 
requested and received approval for lesser dimensions than that in 
criteria based on a performance test referred to as a ``stretcher 
test.'' As applied, this test required 4 persons to carry a fifth 
person on a stretcher through the area in question. The purpose of the 
``stretcher test'' was to demonstrate that the lesser dimension would 
not delay escape. The final rule permits lesser escapeway heights and 
widths under specific circumstances provided the height and width 
maintained enable miners to escape quickly in an emergency. The final 
rule requires that when there is a need to determine whether sufficient 
height or width is provided, MSHA may require a stretcher test where 4 
persons carry a miner through the area in question on a stretcher.
    This commenter suggested that the results of a stretcher test could 
be manipulated by having the most fit miners carry the smallest miner. 
MSHA continues to believe that the stretcher test is appropriate. 
MSHA's experience is that the stretcher test provides a good measure of 
the ability of miners to escape.
    Since the escape of miners is not impeded, the demonstration that 
there is no delay in escape assures that there is no reduction in 
safety.
    MSHA received similar comments regarding the dimensions of 
escapeways developed on or after November 16, 1992, (the effective date 
of the existing rule). Commenters suggested that where these escapeways 
pass across or under overcasts or undercasts, the height of the 
escapeway should be permitted to be less than 5 feet provided the 
height is sufficient to enable miners, including disabled persons, to 
escape quickly in an emergency situation. This suggestion is not 
adopted in the final rule since sufficient clearance should have been 
provided in these escapeways through proper planning and engineering. 
Also, MSHA's experience does not reveal any compliance problems 
associated with the standards since November 1992.
    One commenter recommended changing the phrase ``disabled persons'' 
in paragraph (d)(3) to ``injured persons.'' In support of this 
recommendation, the commenter stated that the phrase is intended to 
include persons who may be injured but not necessarily disabled. MSHA 
does not believe that the change is needed since there are many 
situations that occur underground that can result in a person being 
injured but not severely enough to need assistance (i.e. disabled) to 
be transported from the mine. An escapeway that will permit the 
transport of disabled persons, i.e. the more severely injured persons, 
can be expected to accommodate persons with lesser injuries. The term 
disabled with respect to the concept of injured has existed in the 
regulations for over 25 years and MSHA is not aware of any problems 
with its use.
    Questions arose during informational meetings regarding the 
requirements for the height of doors in escapeways. The final rule, 
like the proposal, permits door heights of less than 5 feet under 
certain conditions. Under the previous rule, escapeway dimensions, 
including door heights, were addressed through criteria and operators 
routinely requested and received approval for lesser dimensions than 
that in criteria based on a performance test referred to as a 
``stretcher test.'' Under the final rule, door heights of less than 5 
feet are permitted provided the operator can demonstrate that persons, 
including disabled persons, can escape without delay. The method of 
demonstration would be the stretcher test, the same as for the 
escapeway. Additionally, there are normally few doors in an escapeway 
and the distance traversed in a door is very short. Passing the 
stretcher test assures that there would be no diminution of safety 
under the new provision. Also, since significant pressure differentials 
can exist in escapeways, doors which are less than 5 feet are easier to 
open.
    Paragraph (d)(4) of the existing rule requires the escapeways be 
maintained at least 6 foot wide with some exceptions. Widths of less 
than 6 feet are permitted in either the primary or the alternate 
escapeway in instances where supplemental roof support is necessary and 
where the route of travel passes through doors or other permanent 
ventilation controls. In both cases, existing paragraph (d)(4) requires 
that the escapeway be at least 4 feet wide. Under the final rule, 
paragraph (d)(4)(iii) permits the alternate 

[[Page 9812]]
escapeway to be less than 4 feet wide under certain conditions.
    Paragraph (d)(4)(iii) applies to the alternate escapeway only and 
allows the escapeway width to be less than 4 feet for the same 
conditions addressed in paragraphs (i) and (ii) if it can be 
demonstrated that sufficient width is maintained to enable persons, 
including disabled persons, to escape quickly in an emergency. The 
conditions that could warrant lesser widths are the locations where the 
alternate escapeway passes through doors or other permanent ventilation 
controls, including constructed approaches to permanent ventilation 
controls and facilities addressed in paragraph (d)(6), or where 
supplemental roof support is required.
    One commenter stated that the alternate escapeway should be 
maintained at a minimum width of 4 feet without exception and noted 
that on several occasions miners have been forced to use the alternate 
escapeway in emergencies. The commenter noted that it could be 
difficult to transport an injured person on a stretcher at widths under 
4 feet. The final rule requires that when there is a need to determine 
whether adequate width is provided, the stretcher test would be 
applied.
    Under the previous rule, approval had been granted for reduced 
escapeway widths based on the stretcher test. These approvals were due 
to the need to provide additional roof support and, in some cases, the 
need for passage through ventilation controls. Additionally, as newer 
portions of a mine age and require additional roof support, the final 
rule allows widths of less than 4 feet in the alternate escapeway where 
this roof support exists, provided the stretcher test is passed. MSHA 
believes this approach achieves the intended result of the standard 
while at the same time addressing the safety issues of providing 
necessary supplemental roof support and permitting travel in the 
alternate escapeway.
    The preamble to the proposal stated that under the existing 
standard Sec. 75.380(d)(4) mobile equipment should not be considered 
when determining escapeway width unless the equipment has been 
permanently abandoned in the escapeway or would be obstructing the 
escapeway for a significant portion of a shift. Commenters objected 
that this interpretation would be unduly restrictive and impractical. 
Commenters noted that certain parked mobile equipment would enhance 
miner safety where the equipment could be used to transport people out 
of the mine in the event of an emergency.
    Experience under the existing and the previous rule indicates that 
track-mounted and rubber-tired equipment which could be used for 
evacuation should be excluded when determining escapeway widths. Track-
mounted supply cars enhance safety by providing a readily available 
supply of rock dust, roof support material, and other essential safety 
related material. Section 75.214 requires that a supply of 
supplementary roof support material and the tools and equipment 
necessary to install the materials be available at a readily accessible 
location on each working section or within 4 crosscuts of each working 
section. In contrast, the Agency received comments that escapeways 
should be maintained at least 6 feet in width except in rare cases 
where roof supports could reduce the width to no less than 4 feet over 
a limited distance.
    The final rule takes a practical approach, preserving the 
requirement that escapeways must be of sufficient width to enable 
miners, including disabled persons, to escape quickly in an emergency. 
The final rule also recognizes that certain necessary mining and 
transportation equipment is located on and near working sections. For 
example, necessary supply cars containing safety related material like 
rock dust, roof support, ventilation control construction material, 
etc., is allowable. Additionally, longwall section equipment commonly 
includes, but may not be limited to, starter box, water pump, section 
belt tailpiece and takeup assembly, section transformer, and emulsion 
pump. Because this equipment is necessary to the operation of the 
longwall, it also is permitted to be in the escapeway near the working 
section under the final rule. In continuous miner sections as well as 
longwall sections, mantrips and personnel transportation equipment, 
which could be utilized in an emergency evacuation, is allowable. The 
final rule would not prohibit this equipment in escapeway entries on or 
near working sections. The rule would require, however, that sufficient 
clearance be maintained to permit rapid escape.
    This aspect of the final rule maintains the historical approach 
taken to addressing issues of clearance in the confined environment of 
underground coal mines. The final rule, while permitting reduced 
dimensions near working sections as discussed above, requires that the 
escapeways always be maintained of sufficient width to enable miners, 
including disabled persons, to escape quickly in an emergency. As 
discussed elsewhere in this preamble, the Agency will assess the 
adequacy of escapeway widths in such areas by means of the stretcher 
test to assure that the width is sufficient to enable miners, including 
disabled persons, to escape quickly in an emergency.
    Like the proposal, the final rule in paragraph (d)(5) revises the 
existing language dealing with the location of escapeways. It provides 
that escapeways shall be located to follow the most direct, safe and 
practical route to the nearest mine opening suitable for the safe 
evacuation of miners. A question arose during an informational meeting 
as to whether MSHA intended that the existing rule eliminate the 
requirement that escapeways be routed to the ``nearest mine opening.'' 
It was not MSHA's intent to change this requirement from the previous 
standard. The existing requirement that the escapeway follow the most 
direct route to the surface would, in fact, require the route to go to 
the nearest mine opening. However, to eliminate any confusion that may 
exist, the final rule revises paragraph (d)(5) and adopts language 
similar to that in previous regulation, Sec. 75.1704-2(a), that is, 
that the escapeway must follow the most direct, safe and practical 
route to the nearest mine opening suitable for the safe evacuation of 
miners.
    One commenter stated that escapeways should not be permitted to 
pass an opening to be routed to a more distant opening. Another 
commenter stated that the nearest mine opening may not always be the 
safest due to roof conditions or other factors. MSHA acknowledges that 
the nearest mine opening may not always be the safest route to the 
surface. A number of factors affect whether or not the safest, most 
direct, practical route has been selected. These factors include roof 
conditions, travel height, fan location, physical dimensions of the 
mine opening, and similar considerations. For example, if bad roof 
conditions are present along the shortest direct route and those roof 
conditions are beyond reasonable control, then an alternate ``safe'' 
route designated by the mine operator may be appropriate. However, the 
presence of roof falls does not necessarily indicate that the 
passageway would not be suitable for evacuation if it is reasonable to 
rehabilitate the area. By way of another example, where coal seam 
thickness varies to the extreme, the shortest route may be through 
lower coal, making travel relatively slow and difficult. An alternate 
route through a high passageway may permit easier travel. Such an 
alternate route, although longer, may be more practical and therefore 
may be more appropriate. 

[[Page 9813]]
Similarly, there can be other instances where the ``nearest mine 
opening'' may not be suitable for safe evacuation of miners. For 
example, an old mine shaft may not be safe for travel because of badly 
deteriorated conditions, such as a deteriorated shaft lining or 
deteriorated timbers, even though the shaft is still suitable for mine 
ventilation purposes.
    As with the existing standard, mine development projections do not 
have to be altered to provide additional rooms, entries, or crosscuts 
for the sole purpose of providing a passageway to the nearest mine 
opening. However, the construction of ventilation controls such as 
stoppings, overcasts and undercasts, or the installation of an escape 
facility may be required to provide the most direct, safe and practical 
route to the surface.
    One commenter suggested that MSHA should require an escapeway plan 
to be approved by the MSHA district manager to assure the most direct 
route to the surface. Existing standards require that escapeways be 
shown on the ventilation map. In addition, as with other regulations, 
inspectors assess whether escapeways follow the most direct, safe and 
practical route to the surface during each regular inspection. 
Accordingly, MSHA does not believe that an additional plan is 
necessary.
    Existing paragraph (f) establishes the requirements for ventilation 
of the primary escapeway and identifies which equipment can be operated 
in the primary escapeway and the fire suppression requirements for this 
equipment. The final rule, like the proposal, modifies paragraph (f) to 
explicitly identify the equipment that is not permitted in the primary 
escapeway and to specify the types of fire suppression systems that are 
to be used and the conditions under which each is to be used on 
equipment permitted in the primary escapeway. This is done by replacing 
existing paragraphs (f)(1) and (f)(2) with paragraphs (f)(1) through 
(f)(7) in the final.
    Existing paragraph (f)(1) requires that one escapeway that is 
ventilated with intake air be designated as the primary escapeway and 
prohibits certain equipment from being used in the primary escapeway in 
areas developed after November 15, 1992. Further, paragraph (f)(1) 
requires fire suppression systems on mobile equipment that is operated 
in the primary escapeway. The final rule transfers the part of existing 
paragraph (f)(1) that specifies the area of the primary escapeway 
affected to paragraph (f)(2).
    The existing rule limited the installation or use of certain 
equipment in areas of the primary escapeway developed after November 
15, 1992. Paragraph (f)(2) of the final rule modifies the existing rule 
for clarity and expands the application of certain requirements 
contained in paragraphs (f)(3) through (f)(7) to the entire primary 
escapeway except those areas of the primary escapeway developed prior 
to March 30, 1970 where separation of the primary escapeway from the 
belt and trolley haulage entries did not exist as of November 16, 1992. 
For areas of mines developed after September 15, 1992, (those areas 
covered by the existing rule) the provisions of paragraphs (f)(3) 
through (f)(7) will be effective as of March 11, 1997. For other areas 
covered by the rule, MSHA has provided for a 1 year phase in period to 
allow mine operators time to effectively plan and implement the 
necessary changes. The phase in period applies to areas of a primary 
escapeway developed between March 30, 1970 and November 16, 1992, and 
to areas of the primary escapeway developed prior to March 30, 1970 
where separation of the belt and trolley haulage entries from the 
primary escapeway existed prior to November 16, 1992.
    Paragraph (f)(3) prohibits certain equipment from being in the 
primary escapeway. Paragraphs (f)(4) and (f)(5) deal with fire 
protection for mobile equipment that is permitted in the primary 
escapeway and paragraph (f)(6) addresses a specific circumstance when 
mobile equipment may operate in a primary escapeway without a fire 
suppression system. Paragraph (f)(7), a provision added to the proposed 
language in response to comments, allows the use of designated 
emergency vehicles or ambulances in the primary escapeway.
    One commenter suggested that the final rule should not provide an 
exception for all areas where separation of the primary escapeway from 
the belt and trolley haulage entry does not exist. The commenter 
recognized, however, that Congress granted an exemption from separation 
requirements for areas of the primary escapeway developed prior to 
March 30, 1970, the effective date of the Act. The intent of the 
proposal was to provide an exemption from the requirements of proposed 
paragraphs (f)(3) through (f)(6) for these same areas. The commenter 
points out that the proposal would have extended the exemption to other 
areas of the primary escapeway where, for one reason or another, 
separation did not exist on November 16, 1992, the effective date of 
the existing rule. The final rule modifies the proposal to clarify that 
the exemption only applies to those areas of the escapeway that were 
developed prior to March 30, 1970 and where separation did not exist on 
November 16, 1992.
    Another commenter correctly interpreted proposed paragraph (f)(2) 
as extending the requirement that limits the types of equipment 
permitted in primary escapeways to areas of the mine developed prior to 
November 16, 1992. The commenter stated that the proposed regulation 
would pose great cost to the industry with no appreciable safety 
benefit derived. A review of the fire history relative to both 
stationary and mobile equipment indicates that fires can and do occur 
on this equipment. Mobile equipment by design is intended to provide 
flexibility in movement and is capable of operating anywhere in the 
mine. Although the accident reports do not specify whether the mobile 
equipment that caught fire was in the primary escapeway when the fire 
started, it is reasonable to conclude that at least some of these fires 
did occur in the primary escapeway. MSHA continues to believe that 
given the importance of the primary escapeway to the safety of miners, 
the extension of the requirements for operation of equipment in the 
primary escapeway is necessary and appropriate.
    Paragraph (f)(3) lists the equipment that is not permitted in the 
primary escapeway. Under paragraph (f)(3)(i) of the final rule, 
operating diesel equipment without an automatic fire suppression system 
is prohibited in the primary escapeway unless it is attended, except as 
provided in paragraphs (f)(6) and (f)(7). One commenter stated that 
attended diesel equipment with a manual fire suppression system 
presents no fire hazard. Another commenter suggested that unattended 
diesel equipment should be prohibited. When diesel equipment is 
operated in the primary escapeway and is properly attended and equipped 
with a manual fire suppression system, the equipment operator can 
immediately respond to a fire, and the safety afforded by the existing 
standard is maintained. If the machine is shut off, however, attendance 
is not necessary. When diesel equipment is to be operated unattended, 
an automatic system is required to protect against fire.
    One commenter stated that ``attended'' should be interpreted to 
mean that the operator is on or within sight of the vehicle. Another 
commenter urged that the standard be clarified to require that the 
operator be at the controls of the equipment. For the purposes of 
Sec. 75.380(f), by ``attended'' MSHA means that the equipment operator 
would be on the mobile 

[[Page 9814]]
equipment or immediately adjacent to the equipment and be capable of 
activating the fire suppression system in the event of a fire.
    The existing standard permits equipment to be in the escapeway for 
purposes of transporting miners and materials and for maintaining the 
escapeway but does not expressly prohibit the haulage of coal in the 
primary escapeway. As a matter of clarification, the final rule 
specifically prohibits coal haulage in the primary escapeway unless 
incidental to cleanup and maintenance of the escapeway. One commenter 
supported the proposed prohibition of coal haulage noting that coal 
haulage would provide a ready source of fuel to a machinery-initiated 
fire. Several commenters expressed a concern that incidental coal 
haulage associated with cleanup and maintenance of the primary 
escapeway would be prohibited under the proposed standard. Cleanup and 
maintenance of the primary escapeway must be permitted. Therefore, the 
final rule modifies the proposal to permit mobile equipment to haul 
coal if incidental to cleanup and maintenance of the primary escapeway.
    Paragraph (f)(3)(iii) prohibits compressors in the primary 
escapeway except as provided in subparagraphs (f)(3)(iii) (A) through 
(C). Subparagraph (A) allows compressors necessary to maintain the 
escapeway in safe, travelable condition; (B) allows compressors that 
are components of equipment such as locomotives and rock dusting 
machines; and, (C) allows compressors of less than five horsepower due 
to the limited fire hazard associated with their operation.
    One commenter described an incident involving a compressor in an 
intake airway, which was located in a fireproof enclosure but was 
improperly ventilated. According to the commenter, smoke and 
contaminants spread throughout the intake entry and reached the 
section, which was then evacuated. This illustrates the importance of 
providing adequate protection from the possible spread of smoke and 
contaminants associated with compressor fires or overheating.
    Paragraph (f)(3)(iv) of the final rule adds battery chargers to the 
equipment included in the proposal that is permitted in the primary 
escapeway provided they are located on or near a working section and 
moved as the section advances or retreats. In all other respects, 
paragraph (f)(3)(iv) of the final rule adopts the proposal. Under 
paragraph (f)(3)(iv), underground transformer stations, battery 
charging stations, substations, and rectifiers cannot be located in the 
primary escapeway except: (A) where necessary to maintain the escapeway 
in safe, travelable condition; and (B) battery chargers and rectifiers 
and power centers with transformers that are either dry-type or contain 
nonflammable liquid, provided they are located on or near a working 
section and are moved as the section advances or retreats. The first 
exception allows work to be performed in the primary escapeway to 
assure its integrity. The second provides for the locations of the 
described equipment at or near working sections if the equipment moves 
with the section. Equipment at or near working sections will normally 
be within a few crosscuts of the working face. In many cases, 
particularly with battery chargers, there may be no practical 
alternative to locating this equipment in the escapeway. In addition, 
Sec. 75.340 provides additional protection when using underground 
electrical equipment.
    Paragraph (f)(3)(v) of the final rule adopts the proposal and 
prohibits water pumps from being in the primary escapeway except as 
provided under paragraphs (f)(3)(v)(A) through (f)(3)(v)(F). The pumps 
that are permitted in the primary escapeway are the same ones that are 
excepted from the requirements of Sec. 75.340 due to the low potential 
for fire associated with their operation. They include: water pumps 
necessary to maintain the escapeway in safe, travelable condition; 
submersible pumps; permissible pumps and associated permissible 
switchgear; pumps located on or near a working section that are moved 
as the section advances or retreats; pumps installed in anthracite 
mines; and small portable pumps. While the existing rule refers to the 
electrical equipment described in Sec. 75.340 (a) and (b)(1), the final 
rule, like the proposal, lists the affected equipment for the 
convenience of the reader. Like Sec. 75.340, paragraph (f)(3)(v) 
applies to water pumps and emulsion pumps when they are located on or 
near the working section and are moved as the section advances or 
retreats. One commenter agreed that pumps may be necessary to maintain 
and rehabilitate the primary escapeway but suggested that a time limit 
be placed on the length of time the pump is allowed to remain in the 
escapeway. MSHA believes that specific conditions at the mine will 
govern the amount of time required for any necessary pumping. 
Therefore, MSHA has not included the suggestion in the final rule since 
the decision relative to time must be made on a case-by-case basis, as 
appropriate.
    Paragraph (f)(4) of the final rule adopts MSHA's proposal with one 
change. As proposed, paragraph (f)(4) would have required the use of 
fire suppression systems on mobile equipment operated in the primary 
escapeway, and would have allowed exceptions for continuous miners and 
as provided in Sec. 75.380 (f)(5) and (f)(6). The final rule adds an 
additional exception for emergency vehicles or ambulances as provided 
in Sec. 75.380(f)(7). Unlike the existing standard, the final rule in 
paragraph (f)(4) permits certain mobile equipment operated in the 
primary escapeway to be protected with a manual fire suppression system 
instead of an automatic system, provided it is attended by a person 
trained in the use and operation of the fire suppression system. MSHA 
believes that when a piece of equipment is operated in the primary 
escapeway and is properly attended and equipped with a manual fire 
suppression system, the equipment operator can immediately respond to 
the situation, and the safety afforded by the existing standard is 
maintained.
    One commenter stated that no electrical, battery or diesel 
equipment, or other equipment such as compressors should be allowed in 
the primary escapeway, except for the purpose of maintenance of the 
escapeway, and that this equipment should have an appropriate fire 
suppression system. Because travel in the escapeway in certain mining 
systems is essential for safety given the design of the mining system 
used, the recommendation of the commenter has not been adopted in the 
final rule. Instead, the final rule provides that certain types of 
mining equipment can be operated in the primary escapeway provided the 
safety precautions set out in the standard are followed. One commenter 
stated that the rule should only apply to mobile equipment which is 
operated in the primary escapeway, since equipment not operating 
presents little or no hazard. MSHA agrees and has incorporated this 
clarification into the final rule.
    Commenters indicated that it is sometimes necessary to withdraw 
face equipment, such as continuous miners, roof bolting machines and 
shuttle cars, into the primary escapeway for a short distance beyond 
the loading point. The equipment is sometimes parked and left there on 
down shifts or between shifts. MSHA notes that, as clarified, the final 
rule does not prohibit this practice. Because the equipment would be 
attended when operated and is provided with manual fire suppression, 
the 

[[Page 9815]]
equipment may be operated in the primary escapeway.
    Following promulgation of the existing rule, some persons construed 
the requirement for an automatic fire suppression system to apply to 
electric face equipment. As explained in the preamble to the proposal, 
this was not the intent of MSHA. To clarify its intent, MSHA issued 
Program Policy Letter No. P92-V-4 on November 16, 1992, addressing the 
operation and location of equipment in primary escapeways. Under 
existing regulations in Subpart L--Fire Protection, face equipment is 
required to be protected by a manual fire suppression system. The final 
rule recognizes and generally conforms with this requirement. Other 
than for an exception to permit a situation such as the movement of 
continuous mining machines between sections without a continuous water 
supply, the final rule requires that when face machinery, equipped with 
a manual fire suppression system, is operated in the primary escapeway, 
it must be attended by a person trained in the proper function and use 
of the fire suppression system. The continuous mining machine exception 
recognizes that the fire suppression system for the continuous mining 
machine often relies on a water supply that may be impracticable to 
provide during equipment moves.
    The final rule requires in paragraph (f)(4) that with exceptions 
for continuous mining machines and as provided in paragraphs (f)(5), 
(f)(6), and (f)(7), each piece of mobile equipment operated in primary 
escapeways shall: (1) be equipped with manually operated fire 
suppression systems installed in compliance with Secs. 75.1107-3 
through 75.1107-16 and be attended continuously; or (2) be equipped 
with an automatic fire suppression system that is capable of both 
automatic and manual activation and installed in compliance with 
Secs. 75.1107-3 through 75.1107-16. Fire suppression systems which were 
installed to meet the 1992 rule will continue to be accepted.
    Under paragraph (f)(5) of the final rule, personnel carriers and 
small personnel conveyances designed and used solely for the 
transportation of personnel and small hand tools can be operated in the 
primary escapeway if either of the requirements under paragraphs (i) or 
(ii) are met. This class of equipment would not include diesel-powered 
pickup trucks, for example, which would be governed by paragraph 
(f)(4). Paragraph (i) requires a multipurpose dry chemical type 
automatic fire suppression system capable of both manual and automatic 
activation. Paragraph (ii) provides an alternative for a class of 
small, battery powered, golf cart type, equipment used for transport of 
persons and small hand tools. In this case, fire extinguishers may be 
used in lieu of a fire suppression system.
    Commenters questioned the need for automatic systems on the class 
of equipment consisting of small, battery powered, golf cart type 
equipment. One commenter suggested that a manual fire suppression 
system should be accepted. After a review of the issue, MSHA has 
concluded that some types of mobile equipment present a very limited 
fire hazard. In the case of small, battery operated, golf cart type, 
conveyances designed and used for the transport of personnel and small 
hand tools, considering the limited hazard, a trained operator provided 
with two 10 pound multi-purpose dry chemical fire extinguishers is 
equivalent in protection to a fire suppression system. Accordingly, as 
an alternative under paragraph (ii), small battery powered, golf cart 
type, equipment may be operated in the primary escapeway if provided 
with two 10 pound multi-purpose dry chemical fire extinguishers. Unlike 
diesel powered equipment, the golf cart type of equipment is shut off 
when not operating and, therefore, attendance is not an issue. The 10 
pound units are standard size extinguishers and are appropriate for the 
equipment involved.
    The system used in accordance with paragraph (i) must be suitable 
for the intended application and listed or approved by a nationally 
recognized independent testing laboratory. The language was proposed as 
two paragraphs but has been combined in the final rule under paragraph 
(i) and an alternative has been added as paragraph (ii). The types of 
machinery which fall under paragraph (f)(5) are not required to meet 
the additional requirements of Secs. 75.1107-3 through 75.1107-16. For 
example, it would be impractical and would not enhance safety to apply 
the minimum dry chemical poundage requirements of Sec. 75.1107-9 to 
small equipment designed and used solely for personnel and small hand 
tools.
    During informational meetings, it was suggested that the term ``dry 
chemical'' would be more accurate and appropriate than the term ``dry 
powder'' used in the existing standard. Like the proposal, the final 
rule adopts this language. MSHA received no comments on this proposed 
revision
    Paragraph (f)(6) of the final rule provides an exception to the 
general requirement and allows mobile equipment not provided with a 
fire suppression system to operate in the primary escapeway if no 
persons are inby other than persons directly engaged in the use or 
moving of the equipment. This provision of the final rule allows for 
the necessary movement of face equipment, such as between sections.
    One commenter stated that the exemption provided in (f)(6) should 
be expanded to allow equipment that does not have a fire suppression 
system to be relocated provided monitoring equipment is utilized for 
carbon monoxide or smoke and two-way communication is available to 
notify appropriate persons. The final rule does not adopt this 
suggestion. During moves, equipment is often laboring at maximum 
capacity and there can be several machines operating simultaneously. 
Under these conditions, equipment fires can develop quickly and the 
products of combustion would be carried to inby workers by the 
ventilating current. By permitting only workers who are directly 
engaged in the operation or movement of the equipment, the final rule 
prevents other workers from being exposed to the hazards of a fire on 
the equipment being moved. Workers operating or engaged in moving the 
equipment will be in a position to quickly identify the hazard and take 
necessary action.
    Another commenter objected to the provision stating that fire 
suppression should be required on all equipment in the primary 
escapeway. This suggestion has not been adopted in the final rule. MSHA 
does not agree that fire suppression is needed when no persons are inby 
or downstream of the equipment being moved. MSHA has concluded that 
either these machines should be equipped with fire suppression, or fire 
extinguishers as in (f)(5)(ii), or no persons should be inby the 
location where the equipment is being operated except those persons 
directly engaged in the operation or movement of the equipment.
    Another commenter suggested that the wording of (f)(6) could be 
read to allow miners to work on a longwall face while equipment not 
equipped with fire suppression is operated anywhere in the primary 
escapeway. This is not permitted by the standard. By including the 
phrase, ``. . . except those persons directly engaged in using or 
moving the equipment'', the persons affected are only those persons in 
the immediate vicinity of the machine. With no persons working inby, 
the use of machinery without a fire suppression system would not expose 
persons to the hazard of toxic gases and fumes from a fire on the 
equipment. The language 

[[Page 9816]]
also would not permit persons to operate mobile equipment without a 
fire suppression system in the primary escapeway while miners are 
downstream working on a longwall face. The controlling factor is 
whether the persons inby are directly engaged in using or moving that 
particular piece of equipment. If they are, and no one else is inby, 
the equipment may be operated without a fire suppression system. For 
example, when moving a longwall shield, no one would be permitted to be 
inby the machine being used to move the shield if the machine is not 
provided with a fire suppression system except those persons moving the 
shield. This would include miners operating other pieces of equipment 
to move other shields.
    Paragraph (f)(7) modifies the existing rule to include a new 
exemption to the requirement that mobile equipment operated in primary 
escapeways have a fire suppression system. Paragraph (f)(7) permits 
mobile equipment designated and used only as emergency vehicles or 
ambulances to operate in the primary escapeway without fire suppression 
systems. It was suggested to MSHA that certain types of emergency 
equipment, such as diesel powered ambulances, should be exempt from the 
requirements for fire suppression systems. Comments were received 
suggesting that ambulances should be exempt because space is extremely 
limited on these vehicles and because they are used infrequently. MSHA 
recognizes the potential benefit in the use of this type of equipment. 
Another commenter objected, foreseeing potential abuses of the 
exemption by mine operators who would designate equipment as ambulances 
but use it as ordinary equipment. The final rule permits emergency 
vehicles to be operated in the primary escapeway without fire 
suppression systems only when this equipment is used for medical 
emergencies.
    This existing rule requires in paragraph (i)(2) that mechanical 
escape facilities be provided and maintained for, ``. . . each slope 
that is part of a designated escapeway that is either inclined 18 
degrees or more from the horizontal or is inclined 9 degrees or more 
from the horizontal and is greater than 1,000 feet in length.'' During 
informational meetings, MSHA became aware of a concern that existing 
paragraph (i)(2) would permit slopes of significant length and 
inclination to exist without any mechanical escape facilities. An 
example would be a slope of 900 feet inclined less than 18 degrees from 
the horizontal. It was suggested that such a slope could be 
particularly difficult for passage of injured persons under cold and 
icy conditions if mechanical escape facilities were not provided. In 
light of this concern, MSHA proposed to require that mechanical escape 
facilities be provided and maintained from the coal seam to the surface 
for each slope that is part of a designated escapeway and is inclined 
more than 9 degrees from the horizontal. The final rule adopts the 
proposal.
    One commenter objected to proposed paragraph (i)(2) indicating that 
facilities are unnecessary in low angle slopes which are of short 
length. Other commenters believed that the 1992 standard was 
appropriate. Another commenter indicated support for the proposal as a 
way to enable persons to escape quickly in an emergency. This commenter 
also noted that escape can be very difficult in icy winter conditions 
in some slopes. After consideration of the comments received, MSHA 
concludes that the proposal was appropriate and the final rule adopts 
this aspect of the proposal.
    One commenter suggested that proposed paragraph (i)(2) could be 
interpreted as requiring mechanical escape facilities for slopes that 
occur naturally underground. It was not MSHA's intent to apply 
paragraph (i)(2) to slopes other than from the coal seam to the 
surface. The final rule clarifies this and requires that mechanical 
escape facilities be provided for each slope from the coal seam to the 
surface that is part of a designated escapeway and is inclined more 
than 9 degrees from the horizontal.
    Like the proposal, the final rule in paragraph(d)(5) revises the 
existing language dealing with the location of escapeways. It provides 
that escapes shall be located to follow the most direct, safe and 
practical route to the nearest mine opening suitable for the safe 
evacuation of miners. A question arose during an informational meeting 
as to whether MSHA intended that the existing rule eliminate the 
requirement that escapeways be routed to the ``nearest mine opening.'' 
It was not MSHA's intent to change this requirement from the previous 
standard. The existing requirement that the escapeway follow the most 
direct route to the surface would, in fact, require the route to go to 
the nearest mine opening. However, to eliminate any confusion that may 
exist, the final rule revises paragraph (d)(5) and adopts language 
similar to that in previous regulation, Sec. 75.1704-2(a), that is, 
that the escapeway must follow the most direct, safe and practical 
route to the nearest mine opening suitable for the safe evacuation of 
miners.
    One commenter stated that escapeways should not be permitted to 
pass an opening to be routed to a more distant opening. Another 
commenter stated that the nearest mine opening may not always be the 
safest due to roof conditions or other factors. MSHA acknowledges that 
the nearest mine opening may not always be the safest route to the 
surface. A number of factors affect whether or not the safest, most 
direct, practical route has been selected. These factors include roof 
conditions, travel height, fan location, physical dimensions of the 
mine opening, and similar considerations. For example, if bad roof 
conditions are present along the shortest direct route and those roof 
conditions are beyond reasonable control, then an alternate ``safe'' 
route designated by the mine operator may be appropriate. However, the 
presence of roof falls does not necessarily indicate that the 
passageway would not be suitable for evacuation if it is reasonable to 
rehabilitate the area. By way of another example, where coal seam 
thickness varies to the extreme, the shortest route may be through 
lower coal, making travel relatively slow and difficult. An alternate 
route through a high passageway may permit easier travel. Such an 
alternate route, although longer, may be more practical and therefore 
may be more appropriate. Similarly, there can be instances where the 
``nearest mine opening'' may not be suitable for safe evacuation of 
miners. For example, an old mine shaft may not be safe for travel 
because of badly deteriorated conditions, such as a deteriorated shaft 
lining or deteriorated timbers, even though the shaft is still suitable 
for mine ventilation purposes.
    As with the existing standard, mine development projections do not 
have to be altered to provide additional rooms, entries, or crosscuts 
for the sole purpose of providing a passageway to the nearest mine 
opening. However, the construction of ventilation controls such as 
stoppings, overcasts and undercasts, or the installation of an escape 
facility may be required to provide the most direct, safe and practical 
route to the surface.
    One commenter suggested that MSHA should require an escapeway plan 
to be approved by the MSHA district manager to assure the most direct 
route to the surface. Existing standards require that escapeways be 
shown on the ventilation map. In addition, as with other regulations, 
inspectors assess whether escapeways follow the most direct, safe and 
practical route to the surface during each regular inspection. 
Accordingly, MSHA does not believe that an additional plan is 
necessary. 

[[Page 9817]]

    Existing paragraph (f) establishes the requirements for ventilation 
of the primary escapeway and identifies which equipment can be operated 
in the primary escapeway and the fire suppression requirements for this 
equipment. The final rule, like the proposal, modifies paragraph (f) to 
explicitly identify the equipment that is not permitted in the primary 
escapeway and to specify the types of fire suppression systems that are 
to be used and the conditions under which each is to be used on 
equipment permitted in the primary escapeway. This is done by replacing 
existing paragraphs (f)(1) and (f)(2) with paragraphs (f)(1) through 
(f)(7) in the final.
    Existing paragraph (f)(1) requires that one escapeway that is 
ventilated with intake air be designated as the primary escapeway and 
prohibits certain equipment from being used in the primary escapeway in 
areas developed after November 15, 1992. Further, paragraph (f)(1) 
requires fire suppression systems on mobile equipment that is operated 
in the primary escapeway. The final rule transfers the part of existing 
paragraph (f)(1) that specifies the area of the primary escapeway 
affected to paragraph (f)(2).
    The existing rule limited the installation or use of certain 
equipment in areas of the primary escapeway developed after November 
15, 1992. Paragraph (f)(2) of the final rule modifies the existing rule 
for clarity and expands the application of certain requirements 
contained in paragraphs (f)(3) through (f)(7) to the entire primary 
escapeway except those areas of the primary escapeway developed prior 
to March 30, 1970 where separation of the primary escapeway from the 
belt and trolley haulage entries did not exist as of November 16, 1992. 
For areas of mines developed after September 15, 1992, (those areas 
covered by the existing rule) the provisions of paragraphs (f)(3) 
through (f)(7) will be effective as of March 11, 1997. For other areas 
covered by the rule, MSHA has provided for a 1 year phase in period to 
allow mine operators time to effectively plan and implement the 
necessary changes. The phase in period applies to areas of a primary 
escapeway developed between March 30, 1970 and November 16, 1992, and 
to areas of the primary escapeway developed prior to March 30, 1970 
where separation of the belt and trolley haulage entries from the 
primary escapeway existed prior to November 16, 1992.
    Paragraph (f)(3) prohibits certain equipment from the primary 
escapeway. Paragraphs (f)(4) and (f)(5) deal with fire protection for 
mobile equipment that is permitted in the primary escapeway and 
paragraph (f)(6) addresses a specific circumstance when mobile 
equipment may operate in a primary escapeway without a fire suppression 
system. Paragraph (f)(7), a provision added to the proposed language in 
response to comments, allows the use of designated emergency vehicles 
or ambulances in the primary escapeway.
    One commenter suggested that the final rule should not provide an 
exception for all areas where separation of the primary escapeway from 
the belt and trolley haulage entry does not exist. The commenter 
recognized, however, that Congress granted an exemption from separation 
requirements for areas of the primary escapeway developed prior to 
March 30, 1970, the effective date of the Act. The intent of the 
proposal was to provide an exemption from the requirements of proposed 
paragraphs (f)(3) through (f)(6) for these same areas. The commenter 
points out that the proposal would have extended the exemption to other 
areas of the primary escapeway where, for one reason or another, 
separation did not exist on November 16, 1992, the effective date of 
the existing rule. The final rule modifies the proposal to clarify that 
the exemption only applies to those areas of the escapeway that were 
developed prior to March 30, 1970 and where separation did not exist on 
November 16, 1992.
    Another commenter correctly interpreted proposed paragraph (f)(2) 
as extending the requirement that limits the types of equipment 
permitted in primary escapeways to areas of the mine developed prior to 
November 16, 1992. The commenter stated that the proposed regulation 
would pose great cost to the industry with no appreciable safety 
benefit derived. A review of the fire history relative to both 
stationary and mobile equipment indicates that fires can and do occur 
on this equipment. Mobile equipment by design is intended to provide 
flexibility in movement and is capable of operating anywhere in the 
mine. Although the accident reports do not specify whether the mobile 
equipment that caught fire was in the primary escapeway when the fire 
started, it is reasonable to conclude that at least some of these fires 
did occur in the primary escapeway. MSHA continues to believe that 
given the importance of the primary escapeway to the safety of miners, 
the extension of the requirements for operation of equipment in the 
primary escapeway is appropriate.
    Paragraph (f)(3) lists the equipment that is not permitted in the 
primary escapeway. Under paragraph(f)(3)(i) of the final rule, 
operating diesel equipment without an automatic fire suppression system 
is prohibited in the primary escapeway unless it is attended, except as 
provided in paragraphs (f)(6) and (f)(7). One commenter stated that 
attended diesel equipment with a manual fire suppression system 
presents no fire hazard. Another commenter suggested that unattended 
diesel equipment should be prohibited. When diesel equipment is 
operated in the primary escapeway and is properly attended and equipped 
with a manual fire suppression system, the equipment operator can 
immediately respond to a fire, and the safety afforded by the existing 
standard is maintained. If the machine is shut off, however, attendance 
is not necessary. When diesel equipment is to be operated unattended, 
an automatic system is required to protect against fire.
    One commenter stated that ``attended'' should be interpreted to 
mean that the operator is on or within sight of the vehicle. Another 
commenter urged that the standard be clarified to require that the 
operator be at the controls of the equipment. For the purposes of 
Sec. 75.380(f), by ``attended'' MSHA means that the equipment operator 
would be on the mobile equipment or immediately adjacent to the 
equipment and be capable of activating the fire suppression system 
immediately in the event of a fire.
    The existing standard permits equipment to be in the escapeway for 
purposes of transporting miners and materials and for maintaining the 
escapeway but does not expressly prohibit the haulage of coal in the 
primary escapeway. As a matter of clarification, the final rule 
specifically prohibits coal haulage in the primary escapeway unless 
incidental to cleanup and maintenance of the escapeway. One commenter 
supported the proposed prohibition of coal haulage noting that coal 
haulage would provide a ready source of fuel to a machinery-initiated 
fire. Several commenters expressed a concern that incidental coal 
haulage associated with cleanup and maintenance of the primary 
escapeway would be prohibited under the proposed standard. Cleanup and 
maintenance of the primary escapeway must be permitted. Therefore, the 
final rule modifies the proposal to permit mobile equipment to haul 
coal if incidental to cleanup and maintenance of the primary escapeway.
    Paragraph (f)(3)(iii) prohibits compressors in the primary 
escapeway except as provided in subparagraphs (f)(3)(iii) (A) through 
(C). Subparagraph 

[[Page 9818]]
(A) allows compressors necessary to maintain the escapeway in safe, 
travelable condition; (B) allows compressors that are components of 
equipment such as locomotives and rock dusting machines; and, (C) 
allows compressors of less than five horsepower due to the limited fire 
hazard associated with their operation.
    One commenter described an incident involving a compressor in an 
intake airway, which was located in a fireproof enclosure but was 
improperly ventilated. According to the commenter, smoke and 
contaminants spread throughout the intake entry and reached the 
section, which was then evacuated. This illustrates the importance of 
providing adequate protection from the possible spread of smoke and 
contaminants associated with compressor fires or overheating.
    Paragraph (f)(3)(iv) of the final rule adds battery chargers to the 
equipment included in the proposal that is permitted in the primary 
escapeway provided it is located on or near a working section and is 
moved as the section advances or retreats. In all other respects, 
paragraph (f)(3)(iv) of the final rule adopts the proposal. Under 
paragraph (f)(3)(iv), underground transformer stations, battery 
charging stations, substations, and rectifiers cannot be located in the 
primary escapeway except: (A) where necessary to maintain the escapeway 
in safe, travelable condition; and (B) battery chargers and rectifiers 
and power centers with transformers that are either dry-type or contain 
nonflammable liquid, provided they are located on or near a working 
section and are moved as the section advances or retreats. The first 
exception allows work to be performed in the primary escapeway to 
assure its integrity. The second provides for the locations of the 
described equipment at or near working sections if the equipment moves 
with the section. Equipment at or near working sections will normally 
be within a few crosscuts of the working face. In many cases, 
particularly with battery chargers, there may be no practical 
alternative to locating this equipment in the escapeway. In addition, 
Sec. 75.340 provides additional protection when using underground 
electrical equipment.
    Paragraph (f)(3)(v) of the final rule adopts the proposal and 
prohibits water pumps from being in the primary escapeway except as 
provided under paragraphs (f)(3)(v)(A) through (f)(3)(v)(F). The pumps 
that are permitted in the primary escapeway are the same ones that are 
excepted from the requirements of Sec. 75.340 due to the low potential 
for fire associated with their operation. They include: water pumps 
necessary to maintain the escapeway in safe, travelable condition; 
submersible pumps; permissible pumps and associated permissible 
switchgear; pumps located on or near a working section that are moved 
as the section advances or retreats; pumps installed in anthracite 
mines; and small portable pumps. While the existing rule refers to the 
electrical equipment described in Sec. 75.340 (a) and (b)(1), the final 
rule, like the proposal, lists the affected equipment for the 
convenience of the reader. Like Sec. 75.340, paragraph (f)(3)(v) 
applies to water pumps and emulsion pumps when they are located on or 
near the working section and are moved as the section advances or 
retreats. One commenter agreed that pumps may be necessary to maintain 
and rehabilitate the primary escapeway but suggested that a time limit 
be placed on the length of time the pump is allowed to remain in the 
escapeway. MSHA believes that specific conditions at the mine will 
govern the amount of time required for any necessary pumping. 
Therefore, MSHA has not included the suggestion in the final rule since 
the decision relative to time must be made on a case-by-case basis, as 
appropriate.
    Paragraph (f)(4) of the final rule adopts MSHA's proposal with one 
change. As proposed, paragraph (f)(4) would have required the use of 
fire suppression systems on mobile equipment operated in the primary 
escapeway, and would have allowed exceptions for continuous miners and 
as provided in Sec. 75.380(f)(5)and (f)(6). The final rule adds an 
additional exception for emergency vehicles or ambulances as provided 
in Sec. 75.380(f)(7). Unlike the existing standard, the final rule in 
paragraph (f)(4) permits certain mobile equipment operated in the 
primary escapeway to be protected with a manual fire suppression system 
instead of an automatic system, provided it is continuously attended by 
a person trained in the use and operation of the fire suppression 
system. MSHA believes that when a piece of equipment is operated in the 
primary escapeway and is properly attended and equipped with a manual 
fire suppression system, the equipment operator can immediately respond 
to the situation, and the safety afforded by the existing standard is 
maintained.
    One commenter stated that no electrical, battery or diesel 
equipment, or other equipment such as compressors should be allowed in 
the primary escapeway, except for the purpose of maintenance of the 
escapeway, and that this equipment should have an appropriate fire 
suppression system. Because travel in the escapeway in certain mining 
systems is essential for safety given the design of the mining system 
used, the recommendation of the commenter has not been adopted in the 
final rule. Instead, the final rule provides that certain types of 
mining equipment can be operated in the primary escapeway provided the 
safety precautions set out in the standard are followed. One commenter 
stated that the rule should only apply to mobile equipment which is 
operated in the primary escapeway, since equipment not operating 
presents little or no hazard. MSHA agrees and has incorporated this 
clarification into the final rule.
    Commenters indicated that it is sometimes necessary to withdraw 
face equipment, such as continuous miners, roof bolting machines and 
shuttle cars, into the primary escapeway for a short distance beyond 
the loading point. The equipment is sometimes parked and left there on 
down shifts or between shifts. MSHA notes that, as clarified, the final 
rule does not prohibit this practice. Because the equipment would be 
attended when operated and is provided with manual fire suppression, 
the equipment may be operated in the primary escapeway.
    Following promulgation of the existing rule, some persons construed 
the requirement for an automatic fire suppression system to apply to 
electric face equipment. As explained in the preamble to the proposal, 
this was not the intent of MSHA. To clarify its intent, MSHA issued 
Program Policy Letter No. P92-V-4 on November 16, 1992, addressing the 
operation and location of equipment in primary escapeways. Under 
existing regulations in Subpart L--Fire Protection, face equipment is 
required to be protected by a manual fire suppression system. The final 
rule recognizes and generally conforms with this requirement. Other 
than for an exception to permit a situation such as the movement of 
continuous mining machines between sections without a continuous water 
supply, the final rule requires that when face machinery, equipped with 
a manual fire suppression system, is operated in the primary escapeway, 
it must be attended by a person trained in the proper function and use 
of the fire suppression system. The continuous mining machine exception 
recognizes that the fire suppression system for the continuous mining 
machine often relies on a water supply that may be impracticable to 
provide during equipment moves. 

[[Page 9819]]

    The final rule requires in paragraph (f)(4) that with exceptions 
for continuous mining machines and as provided in paragraphs (f)(5), 
(f)(6), and (f)(7), each piece of mobile equipment operated in primary 
escapeways shall: (1) be equipped with manually operated fire 
suppression systems installed in compliance with Secs. 75.1107-3 
through 75.1107-16 and be attended continuously; or (2) be equipped 
with an automatic fire suppression system that is capable of both 
automatic and manual activation and installed in compliance with 
Secs. 75.1107-3 through 75.1107-16.
    Under paragraph (f)(5) of the final rule, personnel carriers and 
small personnel conveyances designed and used solely for the 
transportation of personnel and small hand tools can be operated in the 
primary escapeway if either of the requirements under paragraphs (i) or 
(ii) are met. Paragraph (i) requires a multipurpose dry chemical type 
automatic fire suppression system capable of both manual and automatic 
activation. Paragraph (ii) provides an alternative for a class of 
small, battery powered, golf cart type, equipment used for transport of 
persons and small hand tools. In this case, fire extinguishers may be 
used in lieu of a fire suppression system.
    Commenters questioned the need for automatic systems on the class 
of equipment consisting of small, battery powered, golf cart type 
equipment. One commenter suggested that a manual fire suppression 
system should be accepted. After a review of the issue, MSHA has 
concluded that some types of mobile equipment present a very limited 
fire hazard. In the case of small, battery operated, golf cart type, 
conveyances designed and used for the transport of personnel and small 
hand tools, considering the limited hazard, a trained operator provided 
with two 10 pound multi-purpose dry chemical fire extinguishers is 
equivalent in protection to a fire suppression system. Accordingly, as 
an alternative under paragraph (ii), small battery powered, golf cart 
type, equipment may be operated in the primary escapeway if provided 
with two 10 pound multi-purpose dry chemical fire extinguishers. Unlike 
diesel powered equipment, the golf cart type of equipment is shut off 
when not operating and, therefore, attendance is not an issue. The 10 
pound units are standard size extinguishers and are appropriate for the 
equipment involved.
    The system used in accordance with paragraph (i) must be suitable 
for the intended application and listed or approved by a nationally 
recognized independent testing laboratory. The language was proposed as 
two paragraphs but has been combined in the final rule under paragraph 
(i) and an alternative has been added as paragraph (ii). The types of 
machinery which fall under paragraph (f)(5) are not required to meet 
the additional requirements of Secs. 75.1107-3 through 75.1107-16. For 
example, it would be impractical and would not enhance safety to apply 
the minimum dry chemical poundage requirements of Sec. 75.1107-9 to 
small equipment designed and used solely for personnel and small hand 
tools.
    During informational meetings, it was suggested that the term ``dry 
chemical'' would be more accurate and appropriate than the term ``dry 
powder'' used in the existing standard. Like the proposal, the final 
rule adopts this language. MSHA received no comments on this proposed 
revision.
    Paragraph (f)(6) of the final rule provides an exception to the 
general requirement and allows mobile equipment not provided with a 
fire suppression system to operate in the primary escapeway if no 
persons are inby other than persons directly engaged in the use or 
moving of the equipment. This provision of the final rule allows for 
the necessary movement of face equipment, such as between sections.
    One commenter stated that the exemption provided in (f)(6) should 
be expanded to allow equipment that does not have a fire suppression 
system to be relocated provided monitoring equipment is utilized for 
carbon monoxide or smoke and two-way communication is available to 
notify appropriate persons. The final rule does not adopt this 
suggestion. During moves, equipment is often laboring at maximum 
capacity and there can be several machines operating simultaneously. 
Under these conditions, equipment fires can develop quickly and the 
products of combustion would be carried to inby workers by the 
ventilating current. By permitting only workers who are directly 
engaged in the operation or movement of the equipment, the final rule 
prevents other workers from being exposed to the hazards of a fire on 
the equipment being moved. Workers operating or engaged in moving the 
equipment will be in a position to quickly identify the hazard and take 
necessary action.
    Another commenter objected to the provision stating that fire 
suppression should be required on all equipment in the primary 
escapeway. This suggestion has not been adopted in the final rule. MSHA 
does not agree that fire suppression is needed when no persons are inby 
or downstream of the equipment being moved. MSHA has concluded that 
either these machines should be equipped with fire suppression, or fire 
extinguishers as in (f)(5)(ii), or no persons should be inby the 
location where the equipment is being operated except those persons 
directly engaged in the operation or movement of the equipment.
    Another commenter suggested that the wording of (f)(6) could be 
read to allow miners to work on a longwall face while equipment not 
equipped with fire suppression is operated anywhere in the primary 
escapeway. This is not permitted by the standard. By including the 
phrase, ``* * * except those persons directly engaged in using or 
moving the equipment'', the persons affected are only those persons in 
the immediate vicinity of the machine. With no persons working inby, 
the use of machinery without a fire suppression system would not expose 
persons to the hazard of toxic gases and fumes from a fire on the 
equipment. The language also would not permit persons to operate mobile 
equipment without a fire suppression system in the primary escapeway 
while miners are downstream working on a longwall face. The controlling 
factor is whether the persons inby are directly engaged in using or 
moving that particular piece of equipment. If they are, and no one else 
is inby, the equipment may be operated without a fire suppression 
system. For example, when moving a longwall shield, no one would be 
permitted to be inby the machine being used to move the shield if the 
machine is not provided with a fire suppression system except those 
persons moving the shield. This would include miners operating other 
pieces of equipment to move other shields.
    Paragraph (f)(7) modifies the existing rule to include a new 
exemption to the requirement that mobile equipment operated in primary 
escapeways have a fire suppression system. Paragraph (f)(7) permits 
mobile equipment designated and used only as emergency vehicles or 
ambulances to operate in the primary escapeway without fire suppression 
systems. It was suggested to MSHA that certain types of emergency 
equipment, such as diesel powered ambulances, should be exempt from the 
requirements for fire suppression systems. Comments were received 
suggesting that ambulances should be exempt because space is extremely 
limited on these vehicles and because they are used infrequently. MSHA 
recognizes the potential benefit in the use of this type of equipment. 
Another commenter objected, foreseeing potential abuses of 

[[Page 9820]]
the exemption by mine operators who would designate equipment as 
ambulances but use it as ordinary equipment. The final rule permits 
emergency vehicles to be operated in the primary escapeway without fire 
suppression systems only when this equipment is used only for medical 
emergencies.
    This existing rule requires in paragraph (i)(2) that mechanical 
escape facilities be provided and maintained for, ``. . . each slope 
that is part of a designated escapeway that is either inclined 18 
degrees or more from the horizontal or is inclined 9 degrees or more 
from the horizontal and is greater than 1,000 feet in length.'' During 
informational meetings, MSHA became aware of a concern that existing 
paragraph (i)(2) would permit slopes of significant length and 
inclination to exist without any mechanical escape facilities. An 
example would be a slope of 900 feet inclined less than 18 degrees from 
the horizontal. It was suggested that such a slope could be 
particularly difficult for passage of injured persons under cold and 
icy conditions if mechanical escape facilities were not provided. In 
light of this concern, MSHA proposed to require that mechanical escape 
facilities be provided and maintained from the coal seam to the surface 
for each slope that is part of a designated escapeway and is inclined 
more than 9 degrees from the horizontal. The final rule adopts the 
proposal.
    One commenter objected to proposed paragraph (i)(2) indicating that 
facilities are unnecessary in low angle slopes which are of short 
length. Other commenters believed that the 1992 standard was 
appropriate. Another commenter indicated support for the proposal as a 
way to enable persons to escape quickly in an emergency. This commenter 
also noted that escape can be very difficult in icy winter conditions 
in some slopes. After consideration of the comments received, MSHA 
concludes that the proposal was appropriate and the final rule adopts 
this aspect of the proposal.
    One commenter suggested that proposed paragraph (i)(2) could be 
interpreted as requiring mechanical escape facilities for slopes tha t 
occur naturally underground. It was not MSHA's intent to apply 
paragraph (i)(2) to slopes other than from the coal seam to the 
surface. The final rule clarifies this and requires that mechanical 
escape facilities be provided for each slope from the coal seam to the 
surface that is part of a designated escapeway and is inclined more 
than 9 degrees from the horizontal.
Section 75.382 Mechanical Escape Facilities
    Because an escapeway route can sometimes be very long, the most 
safe, direct and practical route to the surface can sometimes involve 
the use of a mechanical escape device such as an automatic elevator or 
similar, but less sophisticated, device. Section 75.382 contains the 
requirements for mechanical escape facilities installed in escapeways 
under Sec. 75.380 and Sec. 75.381. The final rule contains a new 
requirement for certification of escape facility examinations, proposed 
as paragraph (g). The final rule does not retain the other proposed 
changes, paragraphs (h) and (i), that would have added recordkeeping 
and countersigning requirements.
    Under paragraph (g) of the final rule, the designated examiner 
certifies by date, time, and initials that the mechanical escape 
facilities examination required by paragraph Sec. 75.382(c) was 
performed. The certification must be located at or near the facility 
examined. Certification has long been an accepted practice in the 
mining industry for assuring that a required examination has been 
completed. One commenter agreed that certification is necessary and 
supported the revision. The commenter indicated that the facilities are 
often designated as escapeways and therefore there should be some 
assurance that the facilities have been examined and are ready for use. 
Also, in the case of mechanical escape facilities, if certification is 
not provided, precious time could be lost as the escape facility is 
tested prior to use to determine if it is functional and safe.
    Under the proposed paragraphs (h) and (i), a record would have had 
to be made of the examination of the escape facility performed in 
accordance with Sec. 75.382 (c). The results of the examination would 
be included in a record, including any deficiency found along with the 
corrective actions taken to correct the condition. One commenter 
supported the revision requiring records of deficiencies found during 
examinations as well as a record of corrective actions. Other 
commenters objected to additional records, noting that they would not 
enhance safety. After review of the comments, MSHA has concluded that 
certification will achieve the intended objective of assuring the 
safety of mechanical escape. Accordingly, the recordkeeping 
requirements proposed as paragraphs (h) and (i) are omitted from the 
final rule.
    One commenter stated that many companies utilize mobile escape 
facilities to cover more than one mine if the mines are located in 
close proximity. The commenter believed that such an arrangement was 
not considered in the countersigning provisions of the proposal and 
stated, ``The effort required to go to each mine every week and track 
down the mine foreman would be burdensome and unnecessary.'' Paragraph 
(c) of the existing rule requires a weekly examination and a weekly 
test in which the hoist must be run through one complete cycle of 
operation to determine that it is operating properly. The final rule 
requires certification to be completed by the examiner. As indicated 
above, MSHA has concluded that certification will achieve the intended 
objective of assuring that the examinations have been conducted.
    Additional comments were received recommending further 
modifications and additions to Sec. 75.382. For example, a commenter 
recommended 2-way communication capability, with supplies and a holding 
area at the escape facility. These types of comments related to issues 
outside the scope of the rulemaking and were not addressed. Another 
commenter would have MSHA reinstate language from an earlier rule, 
alleging a reduction in protection. MSHA does not believe that there is 
a reduction in protection. Also, the final rule did not propose to 
change the existing requirement that the commenter claimed reduced 
protection, i.e., that a person trained to operate the mechanical 
escape facility always shall be available. MSHA notes that this issue 
is outside the scope of the rulemaking.

Section 75.383 Escapeway Maps and Drills

    When a fire, explosion or other emergency necessitates an immediate 
evacuation of a mine the designated route for miners to leave the mine 
is the escapeway. During a mine fire, passageways, even those 
designated as escapeways, can become smoke filled and the ability to 
see can be drastically reduced. Therefore, it is vitally important that 
miners know the route of travel through the escapeway. Section 75.383 
provides for the posting of escapeway maps so that they are available 
for miners to study and use during an emergency, if necessary. Section 
75.383 also provides for miners to be trained in the escape route 
through escapeway drills. Escapeway drills in mines are similar to fire 
drills in schools and high rise buildings.
    Existing paragraphs (a) and (b)(1) of Sec. 75.383 deal with the 
escapeway map and drill requirements in areas where mechanized mining 
equipment is being 

[[Page 9821]]
installed or removed. Based on comments received, the final rule 
contains 2 revisions to the proposal. The first allows the mine map to 
be readily accessible as an alternative to posting. The second requires 
that miners who are underground when any change is made to the 
escapeway map be immediately notified of the change. These revisions to 
the proposal are discussed below.
    One commenter supported the requirements of (a) and (b)(1) noting 
the hazards and activities where mechanized mining equipment is being 
installed or removed. Another commenter stated that the requirement 
that the map be ``posted'' is impractical in some mines. The commenter 
stated that the rule should simply require that the map be maintained 
on the section to allow the map to be maintained in a map tube, or be 
covered. The commenter also indicated that a map tube could aid miners 
in a rapid escape since the map and tube could easily be taken with the 
miners during the escape. MSHA agrees that the maintenance of a posted 
map could be difficult in some conditions such as in wet or very low 
height mines. Accordingly, the final rule provides an option wherein 
the map may be either posted or be maintained in a location readily 
accessible to all miners. In specifying ``readily accessible'' MSHA 
intends that all miners be made aware of the map location and have 
access to review the map at any time. As an example, a map secured in a 
locked tool chest would not be acceptable.
    One commenter objected to paragraph (a) in two respects. First, 
according to the commenter, the standard does not require maps to show 
the revised escapeway routes until the end of the shift on which the 
changes are made. The commenter believes that changes are projected in 
advance and therefore the maps should be updated immediately. Second, 
the commenter indicated that the requirement that miners must be 
informed of the changes before entering the mine does not address 
affected miners already underground. Many changes within escapeways are 
not known or planned well in advance. Often, such revisions are in 
response to changing conditions underground. MSHA does not believe that 
allowing a portion of one shift is an excessive amount of time to 
update the maps. MSHA does agree, however, that changes to the 
escapeways should be immediately brought to the attention of all miners 
who are underground at the time of a change. Accordingly, the final 
rule specifies that all affected miners already underground must be 
immediately notified of the change. This will assure that all affected 
miners are aware of the change from the time the change is implemented.
    While agreeing that each miner's familiarity with escapeways is 
important, one commenter stated that requiring travel by foot in the 
escapeways could cause undue physical stress to some miners in low or 
steeply pitching seams. The commenter continued that the desired result 
could be obtained by requiring full participation in drills where 
transportation is provided and full participation in drills where 
transportation is not provided, unless that escapeway is equipped with 
a continuous, directional life line. MSHA notes that the standard does 
not require travel on foot. Transportation may be used for escapeway 
drills provided that the purpose of the standard can be achieved. That 
purpose is to assure that miners are familiar with the escapeway routes 
and, as specified in (b)(4), before or during practice escapeway 
drills, miners shall be informed of the locations of fire doors, check 
curtains, changes in the routes of travel, and plans for diverting 
smoke from escapeways. Traveling an escapeway in a completely enclosed 
mantrip, such that the route could not be observed, would not meet the 
requirement. As to the concept of exempting drills in the alternate 
escapeway where mechanized transportation is unavailable if a 
directional lifeline exists, MSHA believes that certain minimum 
specifications for lifelines would be needed before such a compliance 
alternative could be considered. This would expand the scope of this 
rulemaking beyond the proposal.
    One commenter suggested an expansion of 75.383 to require: 
directional life lines in both escapeways; communications in both 
escapeways; numbering of all stoppings along escapeways; additional 
SCSR caches; hard hat stickers depicting escapeways and SCSR donning 
procedures; and other measures. While many of the suggestions may have 
merit, they are outside the scope of this rulemaking.
    In the proposal, MSHA solicited comments on a concept to allow 
individual miners to opt out of escapeway drills for health reasons. 
One commenter indicated that a number of additional requirements would 
be needed to assure that any miners opting out would still remain 
familiar with the escapeways. After considering the comments received, 
MSHA has not included an option for miners to opt out of the escapeway 
drills. As one commenter pointed out, it is essential that each miner 
be familiar with the escapeways. MSHA concludes that a number of 
accommodations can be made to provide assistance to any miner 
experiencing difficulty during drills. As discussed above, mobile 
equipment may be used provided that the conveyance is not so enclosed 
that miners cannot observe the route. Operators can allow additional 
time for miners who may encounter difficulty. Also, assistance can be 
provided by other miners, particularly in difficult areas such as 
unusually steep grades. Such assistance would likely also be needed in 
an actual emergency and therefore the drills would be particularly 
instructive to all the miners participating in the drills.
    MSHA believes that for areas where mechanized mining equipment is 
being installed or removed, providing escapeways and posting maps 
identifying these escapeways and conducting the drills specified in the 
standard are essential to maintain safety. These requirements help to 
assure that miners are familiar with escape routes so that should 
urgent escape become necessary, they can reach the surface as quickly 
as possible.

Section 75.384 Longwall and Shortwall Travelways

    Modern mining methods include removing large blocks of coal in one 
continuous operation along a wall which can be several hundred feet 
long. This method is known as longwall or shortwall mining. To avoid 
trapping miners in the face area without a means of escape in the event 
of an emergency, there is a need to have a travelway on the side of the 
block of coal opposite the escapeways. Section 75.384 addresses the 
requirements for a travelway on the tailgate side of a longwall or 
shortwall, the location and marking of the travelway, and procedures to 
follow during a blockage of the travelway.
    MSHA proposed no changes to the existing rule. Likewise, the final 
rule makes no changes to the existing rule. The preamble to the 
proposal explained that MSHA had received comment suggesting that the 
existing rule be modified to provide for additional involvement by 
miners when a roof fall or other blockage occurs that prevents travel 
in the tailgate travelway. MSHA believes that the existing procedures 
and regulations appropriately address the hazards and provide a 
sufficient opportunity for input and involvement for all interested 
parties. The preamble to the proposal contains a discussion of the 
existing procedures and regulations.
    One commenter recommended several additions to existing Sec. 75.384 
while 

[[Page 9822]]
agreeing that maintenance of a tailgate travelway is essential. The 
recommendations included requiring the tailgate travelway to be 
ventilated by intake air. The commenter noted that several mines 
presently ventilate in this manner, providing intake air splits at both 
headgate and tailgate. While this system has certain advantages, it is 
not feasible or practical in all cases.

Section 75.388 Boreholes in Advance of Mining.

    Areas of a mine, or of an adjacent mine, can be located in close 
proximity to an advancing working place but can be inaccessible for a 
variety of reasons. These inaccessible areas of a mine can present 
hazards when mining proceeds inadvertently or improperly into these 
areas. Inaccessible areas may contain potentially dangerous 
accumulations of gases or water, which could result in explosions or 
inundations. To protect against these hazards, Sec. 75.388 requires 
operators to drill boreholes into the coal before they extract it. In 
this manner, the operator can determine whether mining, if continued, 
will penetrate an area where unknown hazards may be present. Boreholes 
are not required when the area toward which mining is advancing is 
accessible and is properly examined.
    The final rule revises requirements for the drilling of boreholes 
in advance of mining. It requires boreholes to be drilled in both ribs 
of advancing working places unless an alternative drilling plan is 
approved by the district manager in accordance with existing paragraph 
(g) of this section. Existing paragraph (c) requires that boreholes be 
drilled in at least one rib of advancing working places described in 
Sec. 75.388 (a). Although MSHA did not intend any change in 
promulgating the existing language, comments indicated that some 
confusion existed. To address this issue, MSHA proposed to revise the 
existing standard and adopt language similar to the regulation which 
was in effect prior to 1992. The proposed revisions to Sec. 75.388 (c) 
would have required bore holes to be drilled in one or both ribs of 
advancing working places described in Sec. 75.388(a), `` . . . as may 
be necessary for adequate protection of miners in such working 
places.''
    Several comments were received in response to the proposal. One 
commenter indicated that the proposed revision was unnecessary since 
the 1992 standard adequately indicated that more than one rib may need 
to be drilled. Another commenter stated that drilling one rib is always 
adequate since required drilling in adjacent places will assure that 
the entire area is explored by drilling. MSHA's experience is that 
working places are seldom developed at the same rate and some may lag 
by significant distances. In addition, entry or room centers are 
ordinarily in excess of the 20 foot drill hole depth specified in the 
standard. Thus, coverage over the entire width of the advancing section 
is not always provided as suggested by the commenter. Another example 
would be where an advance heading approaches an inaccurately mapped 
abandoned mine such that the unknown workings are approached near the 
undrilled ribline. An inundation could occur at the undrilled ribline 
as the working place advanced. To address these hazards, the final rule 
requires drilling of both ribs. If the workings were not discovered 
through drilling, multiple fatalities could result from inundations of 
water, methane, or oxygen deficient atmosphere (black damp). Accidents 
similar to this scenario have occurred and resulted in inundations of 
water, methane, or irrespirable atmospheres.
    One commenter noted that 38 inundations of gases or water occurred 
between 1990 and 1994. MSHA notes that this number represents only 
those accidental cut-throughs which resulted in inundations. It should 
be noted that numerous additional accidental cut-throughs have occurred 
which did not result in inundations. Each of these additional 
accidental cut-throughs demonstrates the potential for a serious or 
fatal accident. The commenter stated that the number of inundations and 
the potential for multiple fatalities warrant a revision to the 
standard to require both ribs to be drilled. Similar comments and 
examples were heard during the public hearings. MSHA agrees.
    MSHA concludes that in general, both ribs should be drilled; 
however, under some circumstances drilling of both ribs may be 
unnecessary. Moreover, MSHA recognizes that there are circumstances 
where it would be unnecessary to drill both ribs at all times. Thus, 
the final rule requires that both ribs be drilled unless the district 
manager grants approval for an alternative drilling pattern under 
existing paragraph (g). Under existing paragraph (g), an alternative 
drilling pattern may be approved which may not require drilling of both 
ribs. As with other plans which are subject to approval, requests for 
alternative drilling patterns will be reviewed on a case by case basis. 
After considering all comments received discussing this issue, MSHA has 
concluded that the hazard of an inundation is properly addressed by the 
final rule which retains sufficient flexibility for a site specific 
drilling pattern if the district manager can be satisfied that the 
alternative is suitable to the particular circumstances.
    Another comment suggested that the minimum distances which trigger 
drilling as specified in Sec. 75.388 (a)(1), (a)(2), and (a)(3) be 
revised to 100, 500, and 500 feet, respectively. In support of the 
suggestion, the commenter noted factors such as inaccurate old mine 
maps, unmapped mining over-boundary or outside the legal limits, lost 
maps or unknown mines, and less than diligent research by some 
operators. The minimum drilling distances in paragraph (a) were not 
proposed for revision and the final rule does not address them. 
However, it is important to note that the distances specified are the 
minimum at which drilling must begin if there is reasonable confidence 
in the position of the old workings. The distances specified provide a 
safety factor to account for slight mining overruns, mapping errors, 
small deliberate omissions, and similar factors in cases where the 
position of the old workings are known with reasonable certainty. In 
cases where old workings are known to exist but the position is unknown 
or known with little confidence, drilling would be necessary in excess 
of the minimum distances specified in (a) to assure compliance with the 
standard.

Section 75.389 Mining into Inaccessible Areas

    While Sec. 75.388 addresses the need to identify inaccessible areas 
to avoid accidentally drilling into an area containing a possible 
hazardous environment, Sec. 75.389 establishes procedures for drilling 
into an inaccessible area that has been identified. Section 75.389 
requires a separate plan be developed and approved for drilling into 
inaccessible areas. Paragraph (c) of the final rule clarifies that the 
requirements of Sec. 75.389(c)(1), (c)(2) and (c)(3) do not apply to 
routine mining-through operations that are part of a retreat section 
ventilation system approved in accordance with Sec. 75.371(f) and (x). 
The final rule retains the proposed language.
    The preamble to the proposal pointed out that, based on comments 
received during informational meetings and other discussions, differing 
interpretations of the application of existing Sec. 75.389 existed. 
Some persons were interpreting paragraph (c) as requiring, for example, 
the mine to be evacuated during the break-through of a pillar split in 
a retreating section. However, paragraphs (a) through (c) of 
Sec. 75.389 were intended to apply during mining-through operations in 
areas subject to Sec. 75.388 

[[Page 9823]]
where hazards and potential hazards may be unknown. The final rule 
revises existing Sec. 75.389(c) by adding an exception for routine 
mining-through operations that are a part of a retreat mining system 
approved in the mine ventilation plan. In some circumstances, the 
mining through occurs during routine mining into an area which is 
covered by an approved mine ventilation plan. In this case, the 
potential hazards have already been addressed in the mine ventilation 
plan. Requiring the operator to submit duplicate plans would not result 
in any safety benefit; therefore, the level of safety provided by the 
existing standard is maintained.

Petitions for Modification

    Operators with petitions for modification that involve the 
standards revised in this rulemaking need to determine the status of 
those petitions before the effective date of the rule. If there are 
sections of this rule that are renumbered but remain substantively 
unchanged from the existing standards, operators with modifications 
granted for these standards need not reapply. However, operators with 
petitions for modifications granted for standards that have been 
revised must comply with the new rule on its effective date. New 
petitions for modification of the final rule may be submitted under 30 
CFR part 44. If Agency assistance is needed, questions should be 
directed to the appropriate MSHA district office.

Redesignation Table

    The following redesignation table lists the section number of the 
existing standard and the section number of the final standard which 
contain revised provisions derived from the corresponding existing 
section.

----------------------------------------------------------------------------------------------------------------
                   Old section                                              New section                         
----------------------------------------------------------------------------------------------------------------
75.310(a)(3)....................................  75.310(a)(3).                                                 
75.310(a)(4)....................................  75.310(a)(4).                                                 
75.310(c).......................................  75.310(c).                                                    
75.310(c).......................................  75.310(c)(1).                                                 
75.310(c).......................................  75.310(c)(2).                                                 
75.310(c).......................................  75.310(c)(4).                                                 
75.310(c)(1)....................................  75.310(c)(4)(i).                                              
75.310(c)(2)....................................  75.310(c)(4)(ii).                                             
75.311(d).......................................  75.311(d).                                                    
75.312(a).......................................  75.312(a).                                                    
75.312(b)(1)....................................  75.312(b)(1), 75.312(b)(1)(ii).                              

75.312(b)(1)(i).................................  75.312(b)(1)(ii)(A).                                          
75.312(b)(1)(ii)................................  75.312(b)(1)(ii)(B).                                          
75.312(c).......................................  75.312(c).                                                    
75.312(d).......................................  75.312(d).                                                    
75.312(f).......................................  75.312(f)(1).                                                 
75.312(g)(1)....................................  75.312(g)(1).                                                 
75.312(g)(3)....................................  75.312(g)(3).                                                 
75.312(h).......................................  75.312(h).                                                    
75.313(c)(2)....................................  75.313(c)(2).                                                 
75.313(c)(3)....................................  75.313(c)(3).                                                 
75.313(d)(1)(i).................................  75.313(d)(1)(i).                                              
75.313(d)(1)(ii)................................  75.313(d)(1)(ii).                                             
75.321(a).......................................  75.321(a)(1).                                                 
75.321(a).......................................  75.321(a)(2).                                                 
75.323(b)(1)(ii)................................  75.323(b)(1)(ii).                                             
75.323(c)(1)....................................  75.323(c)(1).                                                 
75.323(d)(2)(i).................................  75.323(d)(2)(i).                                              
75.325(d).......................................  75.325(d).                                                    
75.333(a).......................................  75.333(a).                                                    
75.333(b)(1)....................................  75.333(b)(1).                                                 
75.333(b)(3)....................................  75.333(b)(3).                                                 
75.333(b)(4)....................................  75.333(b)(4).                                                 
75.333(e)(1)....................................  75.333(e)(1)(i).                                              
75.333(e)(1)....................................  75.333(e)(1)(ii).                                             
75.334(e).......................................  75.334(e).                                                    
75.334(f)(3)....................................  75.334(f)(3).                                                 
75.340(a).......................................  75.340(a)                                                     
75.340(a)(1)....................................  75.340(a)(1)(i).                                              
75.340(a)(2)....................................  75.340(a)(1)(ii).                                             
75.340(a)(3)....................................  75.340(a)(1)(iii).                                            
75.340(a)(3)(i).................................  75.340(a)(1)(iii)(A).                                         
75.340(a)(3)(ii)................................  75.340(a)(1)(iii)(B).                                         
75.340(a).......................................  75.340(a)(2).                                                 
75.340(a)(1)....................................  75.340(a)(2)(i).                                              
75.340(a)(2)....................................  75.340(a)(2)(ii).                                             
75.342(a)(4)....................................  75.342(a)(4).                                                 
75.344(a).......................................  75.344(a).                                                    
75.344(a)(1)....................................  75.344(a)(2).                                                 
75.344(a)(2)....................................  75.344(b).                                                    
75.344(b)(1)....................................  75.344(a)(1).                                                 
75.344(b)(2)....................................  75.344(a)(2).                                                 
75.344(b)(2)(i).................................  75.344(a)(2)(i).                                              

[[Page 9826]]

75.344(b)(2)(ii)................................  75.344(a)(2)(ii).                                             
75.360(a).......................................  75.360(a)(1).                                                 
75.360(b).......................................  75.360(b).                                                    
75.360(b)(1)....................................  75.360(b)(1).                                                 
75.360(b)(3)....................................  75.360(b)(3).                                                 
75.360(b)(4)....................................  75.350(b)(4).                                                 
75.360(b)(6)....................................  75.360(b)(6)(i).                                              
75.360(b)(6)....................................  75.360(b)(6)(ii).                                             
75.360(c).......................................  75.360(c).                                                    
75.360(c)(1)....................................  75.360(c)(1).                                                 
75.360(c)(3.....................................  75.360(c)(3).                                                 
75.360(e).......................................  75.363.                                                       
75.360(f).......................................  75.360(e).                                                    
75.360(g).......................................  75.360(f).                                                    
75.360(h).......................................  75.360(g).                                                    
75.362(a)(1)....................................  75.362(a)(1).                                                 
75.363(a)(2)....................................  75.363.                                                       
75.362(c)(1)....................................  75.362(c)(1).                                                 
75.362(d)(1)(i).................................  75.362(d)(1)(ii).                                             
75.362(d)(1)(ii)................................  75.362(d)(1)(iii).                                            
75.362(d)(2)....................................  75.362(d)(2).                                                 
75.362(g).......................................  75.363.                                                       
75.362(h).......................................  75.363.                                                       
75.364(a)(1)....................................  75.364(a)(1).                                                 
75.364(a)(2)(i).................................  75.364(a)(2)(i).                                              
75.364(a)(2)(ii)................................  75.364(a)(2)(ii).                                             
75.364(a)(2)(iii)...............................  75.364(a)(2)(iii).                                            
75.364(h).......................................  75.364(h).                                                    
75.364(i).......................................  75.364(i).                                                    
75.370(a)(3)....................................  75.370(a)(3).                                                 
75.370(a)(3)....................................  75.370(a)(3)(ii).                                             
75.370(a)(3)....................................  75.370(a)(3)(iii).                                            
75.370(b)(1)....................................  75.370(c)(1).                                                 
75.370(b)(2)....................................  75.370(c)(2).                                                 
75.370(e).......................................  75.370(f).                                                    
75.370(e).......................................  75.370(f)(2).                                                 
75.370(e).......................................  75.370(f)(3).                                                 
75.371(r).......................................  75.371(r).                                                    
75.371(s).......................................  75.371(s).                                                    
75.371(z).......................................  75.371(z).                                                    
75.371(bb)......................................  75.371(bb).                                                   
75.371(cc)......................................  75.371(cc).                                                   
75.372(b)(3)....................................  75.372(b)(3).                                                 
75.380(d)(3)....................................  75.380(d)(3).                                                 
75.380(d)(4)(ii)................................  75.380(d)(4)(ii).                                             
75.380(d)(5)....................................  75.380(d)(5).                                                 
75.380(f).......................................  75.380(f).                                                    
75.380(i)(2)....................................  75.380(i)(2).                                                 
75.383(a).......................................  75.383(a).                                                    
75.388(c).......................................  75.388(c).                                                    
75.389(c)(1)....................................  75.389(c)(1).                                                 
----------------------------------------------------------------------------------------------------------------



III. Paperwork Reduction Act

    The information collection requirements contained in this rule have 
been submitted to the Office of Management and Budget (OMB) for review 
under the Paperwork Reduction Act of 1995 (44 U.S.C. 3501-3520), as 
implemented by OMB in regulations at 5 CFR part 1320. No person may be 
required to respond to, or may be subjected to a penalty for failure to 
comply with, these information collection requirements until they have 
been approved and MSHA has announced the assigned OMB control number. 
The OMB control number, when assigned, will be announced by separate 
notice in the Federal Register. In accordance with Sec. 1320.11(h) of 
the implementing regulations, OMB has 60 days from today's publication 
date in which to approve, disapprove, or instruct MSHA to make a change 
to the information collection requirements in this rule.
    This final rule addresses comments submitted to OMB and MSHA on the 
collection of information requirements in the proposed rule. In 
revising the requirements from those that appeared in the proposed 
rule, MSHA has evaluated the necessity and usefulness of the 
collections of information; reevaluated MSHA's estimate of the 
information collection burden, including the validity of the underlying 
methodology and assumptions; and minimized the burden on respondents 
for the information collection requirements, to the extent possible. 
This final rule provides for the use of electronic storage and 
maintenance of records.

Benefits

    In assessing costs and benefits of the ventilation rule, it is 
important to note that ventilation of underground coal mines is the 
primary method of preventing the accumulation of explosive methane gas, 
controlling harmful respirable dust, and assuring the quality of air 
miners breath. Because 

[[Page 9827]]
of the potential for a large number of fatalities resulting from 
ventilation problems, MSHA has found it prudent to establish multiple 
safety factors and safety work practices to better assure adequate 
protection for miners. It is extremely difficult to specifically 
quantify safety benefits related to each safety factor. However, due to 
the close, confined nature of the workplace in an underground coal 
mine, failure of any safety factors or protective actions related to 
ventilation can have disastrous effects. The introduction of this rule 
lists some of those tragic mine accidents. In the restricted work 
environment of an underground coal mine, failure of a single safety 
factor or noncompliance with a safe work practice could jeopardize the 
well-being of all miners underground. The total effect of the 
provisions in this final rule in conjunction with MSHA's existing 
ventilation standards should decrease the occurrence of fatalities, 
injuries, accidents, and illnesses in underground coal mines.
    With respect to this final rule, the Agency has identified nine 
fatalities and seven injuries which potentially could have been 
prevented by compliance with these provisions. In addition, the final 
rule contains provisions to better assure compliance with the 
respirable dust control parameters specified in the mine ventilation 
plan. Adherence to these parameters helps to maintain a work 
environment free of excessive levels of respirable dust, thereby 
improving long-term health protection for miners and potentially 
reducing the number of miners afflicted with coal workers' 
pneumoconiosis.
    Some provisions clarify the intent of the existing rule. Such 
clarifications should increase the likelihood of compliance and thereby 
will help to increase the probability of preventing a fatality, injury, 
or non-injury accident. For the provisions which offer an alternative 
compliance option, the miners will be provided at least the same level 
of safety provided by an existing requirement. These provisions will 
facilitate compliance by the operator, thereby increasing the potential 
for the rule to reduce the probability of a ventilation-related 
explosion or accident.
    In conclusion, the Agency determined that these provisions will 
increase the probability that compliance with the ventilation rule will 
prevent future ventilation-related accidents and generate a safer 
mining environment.

Compliance Costs and Economic Impact

    MSHA has compared the costs associated with the existing 
requirements with the costs of the new requirements. Based upon the 
available data, MSHA estimates that compliance with the rule will 
produce net total per year costs of approximately $4.0 million for the 
mining industry. This $4.0 million is composed of approximately $0.6 
million in net annualized costs (derived from $4.0 million one-time 
costs) and approximately $3.4 million net annual recurring costs.
    With respect to large underground coal mines the net total per year 
costs will be approximately $3.0 million. This $3.0 million is composed 
of approximately $0.46 million in net annualized costs (derived from 
$3.0 million one-time costs) and approximately $2.54 million net annual 
recurring costs.
    With respect to small underground coal mines the net total per year 
costs will be approximately $1.0 million. This $1.0 million is composed 
of approximately $0.14 million in net annualized costs (derived from 
$1.0 million one-time costs) and approximately $0.82 million net annual 
recurring costs.
    Executive Order 12866 requires that regulatory agencies assess the 
impact to the government for any regulation determined to be a 
significant regulatory action. MSHA does not believe that this rule 
will create any significant cost impacts to the government. The 
regulation can be implemented under existing government practices 
without any substantial equipment or facility expenditures by the 
government.
    The incremental compliance costs for all underground coal mines are 
listed by provision in Table I.

  Table IV-1.--Compliance Costs to Comply With the Ventilation Rule for 
                       all Underground Coal Mines                       
                        [In thousands of dollars]                       
------------------------------------------------------------------------
                                           First                        
                Standard                    year   Annualized    Annual 
                                           costs      costs      costs  
------------------------------------------------------------------------
75.301..................................    (100)        (7)        (20)
75.310..................................     329         47         (70)
75.311..................................  .......  ..........  .........
75.312..................................  .......  ..........    (1,121)
75.313..................................  .......  ..........       322 
75.320..................................  .......  ..........  .........
75.321..................................     250         35          40 
75.323..................................  .......  ..........  .........
75.330..................................  .......  ..........  .........
75.333..................................  .......  ..........  .........
75.334..................................  .......  ..........  .........
75.340..................................      63          9             
75.342..................................      12          2          38 
75.344..................................      57         10       1,256 
75.360..................................     123         17      (1,556)
75.362..................................     420         59       3,275 
75.363..................................  .......  ..........       321 
75.364..................................  .......  ..........       682 
75.370..................................  .......  ..........        67 
75.371..................................  .......  ..........        13 
75.372..................................  .......  ..........  .........
75.380..................................   2,839        436          51 
75.382..................................  .......  ..........        13 
75.388..................................  .......  ..........        53 

[[Page 9828]]

75.389..................................                                
                                         -------------------------------
      Total costs.......................   3,993        608       3,364 
------------------------------------------------------------------------



Regulatory Flexibility Certification

    The Regulatory Flexibility Act requires that agencies evaluate and 
include, wherever possible, compliance alternatives that minimize any 
adverse impact on small businesses when developing regulatory 
standards. MSHA has not exempted small mines from any provision of the 
rule and small mines will benefit from some of the provisions and the 
alternative compliance methods.
    MSHA determined that these revisions will not generate a 
substantial cost increase for small mines. The lack of a substantial 
cost increase for small mines, in conjunction with the fact that 
similar hazards exist in both large and small mining operations, 
indicates that regulatory relief is not warranted for small mining 
operations. Therefore, MSHA has determined that these provisions will 
not have a significantly adverse impact upon a substantial number of 
small entities.
    The incremental costs for small and large mines are listed by 
provision in Table II.

  Table IV-2.--Compliance Costs to Comply With the Ventilation Rule for Small and Large
Underground Coal Mines  
                                            [In thousands of dollars]                                           
----------------------------------------------------------------------------------------------------------------
                                        First year costs          Annualized costs            Annual costs      
             Standard              -----------------------------------------------------------------------------
                                       Small        Large        Small        Large        Small        Large   
----------------------------------------------------------------------------------------------------------------
75.301............................                     (100)                       (7)                      (20)
75.310............................          273          56            39           8          (78)           8 
75.311............................                                                                              
75.312............................                                                                       (1,121)
75.313............................                                                              55          267 
75.320............................                                                                              
75.321............................                      250                        35                        40 
75.323............................                                                                              
75.330............................                                                                              
75.333............................                                                                              
75.334............................                                                                              
75.340............................            4          59             1           8                           
75.342............................            6           6             1           1           18           20 
75.344............................                       57                        10           43        1,213 
75.360............................           37          86             5          12          100       (1,656)
75.362............................           80         340            11          48          409        2,866 
75.363............................                                                              98          223 
75.364............................                                                             126          556 
75.370............................                                                              12           55 
75.371............................                                                               6            7 
75.372............................                                                                              
75.380............................          585       2,254            89         347            6           45 
75.382............................                                                                           13 
75.388............................                                                              25           28 
75.389............................                                                                              
                                   -----------------------------------------------------------------------------
      Total.......................          985       3,008           146         462          820        2,544 
----------------------------------------------------------------------------------------------------------------

List of Subjects in 30 CFR Part 75

    Escapeways, Mine safety and health, Underground coal mines, 
Ventilation.

    Dated: March 4, 1996.
J. Davitt McAteer,
Assistant Secretary for Mine Safety and Health.

    Accordingly, part 75, subchapter O, chapter I, title 30 of the Code 
of Federal Regulations is amended as follows:

PART 75--MANDATORY SAFETY STANDARDS--UNDERGROUND COAL MINES

    1. The authority citation for part 75 is revised to read as 
follows:

    Authority: 30 U.S.C. 811.

    2. Subpart D of part 75 is revised to read as follows: 

[[Page 9829]]


Subpart D--Ventilation

Sec.
75.300  Scope.
75.301  Definitions.
75.302  Main mine fans.
75.310  Installation of main mine fans.
75.311  Main mine fan operation.
75.312  Main mine fan examinations and records.
75.313  Main mine fan stoppage with persons underground.
75.320  Air quality detectors and measurement devices.
75.321  Air quality.
75.322  Harmful quantities of noxious gases.
75.323  Actions for excessive methane.
75.324  Intentional changes in the ventilation system.
75.325  Air quantity.
75.326  Mean entry air velocity.
75.327  Air courses and trolley haulage systems.
75.330  Face ventilation control devices.
75.331  Auxiliary fans and tubing.
75.332  Working sections and working places.
75.333  Ventilation controls.
75.334  Worked-out areas and areas where pillars are being 
recovered.
75.335  Construction of seals.
75.340  Underground electrical installations.
75.341  Direct-fired intake air heaters.
75.342  Methane monitors.
75.343  Underground shops.
75.344  Compressors.
75.350  Air courses and belt haulage entries.
75.351  Atmospheric monitoring system (AMS).
75.352  Return air courses.
75.360  Preshift examination.
75.361  Supplemental examination.
75.362  On-shift examination.
75.363  Hazardous conditions; posting, correcting and recording.
75.364  Weekly examination.
75.370  Mine ventilation plan; submission and approval.
75.371  Mine ventilation plan; contents.
75.372  Mine ventilation map.
75.373  Reopening mines.
75.380  Escapeways; bituminous and lignite mines.
75.381  Escapeways; anthracite mines.
75.382  Mechanical escape facilities.
75.383  Escapeway maps and drills.
75.384  Longwall and shortwall travelways.
75.385  Opening new mines.
75.386  Final mining of pillars.
75.388  Boreholes in advance of mining.
75.389  Mining into inaccessible areas.


Sec. 75.300  Scope.

    This subpart sets requirements for underground coal mine 
ventilation.


Sec. 75.301  Definitions.

    In addition to the applicable definitions in Sec. 75.2, the 
following definitions apply in this subpart.
    Air course. An entry or a set of entries separated from other 
entries by stoppings, overcasts, other ventilation control devices, or 
by solid blocks of coal or rock so that any mixing of air currents 
between each is limited to leakage.
    Incombustible. Incapable of being burned.
    Intake air. Air that has not yet ventilated the last working place 
on any split of any working section, or any worked-out area, whether 
pillared or nonpillared.
    Intrinsically safe. Incapable of releasing enough electrical or 
thermal energy under normal or abnormal conditions to cause ignition of 
a flammable mixture of methane or natural gas and air of the most 
easily ignitable composition.
    Noncombustible Structure or Area. Describes a structure or area 
that will continue to provide protection against flame spread for at 
least 1 hour when subjected to a fire test incorporating an ASTM E119-
88 time/temperature heat input, or equivalent.
    Noncombustible Material. Describes a material which when used to 
construct a ventilation control results in a control that will continue 
to serve its intended function for 1 hour when subjected to a fire test 
incorporating an ASTM E119-88 time/temperature heat input, or 
equivalent.
    Return air. Air that has ventilated the last working place on any 
split of any working section or any worked-out area whether pillared or 
nonpillared. If air mixes with air that has ventilated the last working 
place on any split of any working section or any worked-out area, 
whether pillared or nonpillared, it is considered return air. For the 
purposes of Sec. 75.507-1, air that has been used to ventilate any 
working place in a coal producing section or pillared area, or air that 
has been used to ventilate any working face if such air is directed 
away from the immediate return is return air. Notwithstanding the 
definition of intake air, for the purpose of ventilation of structures, 
areas or installations that are required by this subpart D to be 
ventilated to return air courses, and for ventilation of seals, other 
air courses may be designated as return air courses by the operator 
only when the air in these air courses will not be used to ventilate 
working places or other locations, structures, installations or areas 
required to be ventilated with intake air.
    Worked-out area. An area where mining has been completed, whether 
pillared or nonpillared, excluding developing entries, return air 
courses, and intake air courses.


Sec. 75.302  Main mine fans.

    Each coal mine shall be ventilated by one or more main mine fans. 
Booster fans shall not be installed underground to assist main mine 
fans except in anthracite mines. In anthracite mines, booster fans 
installed in the main air current or a split of the main air current 
may be used provided their use is approved in the ventilation plan.


Sec. 75.310  Installation of main mine fans.

    (a) Each main mine fan shall be--
    (1) Installed on the surface in an incombustible housing;
    (2) Connected to the mine opening with incombustible air ducts;
    (3) Equipped with an automatic device that gives a signal at the 
mine when the fan either slows or stops. A responsible person 
designated by the operator shall always be at a surface location at the 
mine where the signal can be seen or heard while anyone is underground. 
This person shall be provided with two-way communication with the 
working sections and work stations where persons are routinely assigned 
to work for the majority of a shift;
    (4) Equipped with a pressure recording device or system. Mines 
permitted to shut down main mine fans under Sec. 75.311 and which do 
not have a pressure recording device installed on main mine fans shall 
have until March 11, 1997 to install a pressure recording device or 
system on all main mine fans. If a device or system other than a 
circular pressure recorder is used to monitor main mine fan pressure, 
the monitoring device or system shall provide a continuous graph or 
continuous chart of the pressure as a function of time. At not more 
than 7-day intervals, a hard copy of the continuous graph or chart 
shall be generated or the record of the fan pressure shall be stored 
electronically. When records of fan pressure are stored electronically, 
the system used to store these records shall be secure and not 
susceptible to alteration and shall be capable of storing the required 
data. Records of the fan pressure shall be retained at a surface 
location at the mine for at least 1 year and be made available for 
inspection by authorized representatives of the Secretary and the 
representative of miners;
    (5) Protected by one or more weak walls or explosion doors, or a 
combination of weak walls and explosion doors, located in direct line 
with possible explosive forces;
    (6) Except as provided under paragraph (e) of this section, offset 
by at least 15 feet from the nearest side of the mine opening unless an 
alternative method of protecting the fan and its associated components 
is approved in the ventilation plan. 

[[Page 9830]]

    (b)(1) If an electric motor is used to drive a main mine fan, the 
motor shall operate from a power circuit independent of all mine power 
circuits.
    (2) If an internal combustion engine is used to drive a main mine 
fan--
    (i) The fuel supply shall be protected against fires and 
explosions;
    (ii) The engine shall be installed in an incombustible housing and 
be equipped with a remote shut-down device;
    (iii) The engine and the engine exhaust system shall be located out 
of direct line of the air current exhausting from the mine; and
    (iv) The engine exhaust shall be vented to the atmosphere so that 
the exhaust gases do not contaminate the mine intake air current or any 
enclosure.
    (c) If a main mine fan monitoring system is used under Sec. 75.312, 
the system shall--
    (1) Record, as described in paragraph (a)(4) the mine ventilating 
pressure;
    (2) Monitor bearing temperature, revolutions per minute, vibration, 
electric voltage, and amperage;
    (3) Provide a printout of the monitored parameters, including the 
mine ventilating pressure within a reasonable period, not to exceed the 
end of the next scheduled shift during which miners are underground; 
and
    (4) Be equipped with an automatic device that signals when--
    (i) An electrical or mechanical deficiency exists in the monitoring 
system; or
    (ii) A sudden increase or loss in mine ventilating pressure occurs.
    (5) Provide monitoring, records, printouts, and signals required by 
paragraphs (c)(1) through (c)(4) at a surface location at the mine 
where a responsible person designated by the operator is always on duty 
and where signals from the monitoring system can be seen or heard while 
anyone is underground. This person shall be provided with two-way 
communication with the working sections and work stations where persons 
are routinely assigned to work for the majority of a shift.
    (d) Weak walls and explosion doors shall have cross-sectional areas 
at least equal to that of the entry through which the pressure from an 
explosion underground would be relieved. A weak wall and explosion door 
combination shall have a total cross-sectional area at least equal to 
that of the entry through which the pressure from an explosion 
underground would be relieved.
    (e) If a mine fan is installed in line with an entry, a slope, or a 
shaft--
    (1) The cross-sectional area of the pressure relief entry shall be 
at least equal to that of the fan entry;
    (2) The fan entry shall be developed out of direct line with 
possible explosive forces;
    (3) The coal or other solid material between the pressure relief 
entry and the fan entry shall be at least 2,500 square feet; and
    (4) The surface opening of the pressure relief entry shall be not 
less than 15 feet nor more than 100 feet from the surface opening of 
the fan entry and from the underground intersection of the fan entry 
and pressure relief entry.
    (f) In mines ventilated by multiple main mine fans, incombustible 
doors shall be installed so that if any main mine fan stops and air 
reversals through the fan are possible, the doors on the affected fan 
automatically close.


Sec. 75.311  Main mine fan operation.

    (a) Main mine fans shall be continuously operated, except as 
otherwise approved in the ventilation plan, or when intentionally 
stopped for testing of automatic closing doors and automatic fan signal 
devices, maintenance or adjustment of the fan, or to perform 
maintenance or repair work underground that cannot otherwise be made 
while the fan is operating.
    (b) Except as provided in paragraph (c) of this section, when a 
main mine fan is intentionally stopped and the ventilating quantity 
provided by the fan is not maintained by a back-up fan system--
    (1) Only persons necessary to evaluate the effect of the fan 
stoppage or restart, or to perform maintenance or repair work that 
cannot otherwise be made while the fan is operating, shall be permitted 
underground;
    (2) Mechanized equipment shall be shut off before stopping the fan; 
and
    (3) Electric power circuits entering underground areas of the mine 
shall be deenergized.
    (c) When a back-up fan system is used that does not provide the 
ventilating quantity provided by the main mine fan, persons may be 
permitted in the mine and electric power circuits may be energized as 
specified in the approved ventilation plan.
    (d) If an unusual variance in the mine ventilation pressure is 
observed, or if an electrical or mechanical deficiency of a main mine 
fan is detected, the mine foreman or equivalent mine official, or in 
the absence of the mine foreman or equivalent mine official, a 
designated certified person acting for the mine foreman or equivalent 
mine official shall be notified immediately, and appropriate action or 
repairs shall be instituted promptly.
    (e) While persons are underground, a responsible person designated 
by the operator shall always be at a surface location where each main 
mine fan signal can be seen or heard.
    (f) The area within 100 feet of main mine fans and intake air 
openings shall be kept free of combustible material, unless alternative 
precautions necessary to provide protection from fire or other products 
of combustion are approved in the ventilation plan.
    (g) If multiple mine fans are used, the mine ventilation system 
shall be designed and maintained to eliminate areas without air 
movement.
    (h) Any atmospheric monitoring system operated during fan stoppages 
shall be intrinsically safe.


Sec. 75.312  Main mine fan examinations and records.

    (a) To assure electrical and mechanical reliability of main mine 
fans, each main mine fan and its associated components, including 
devices for measuring or recording mine ventilation pressure, shall be 
examined for proper operation by a trained person designated by the 
operator. Examinations of main mine fans shall be made at least once 
each day that the fan operates, unless a fan monitoring system is used. 
No examination is required on any day when no one, including certified 
persons, goes underground, except that an examination shall be 
completed prior to anyone entering the mine.
    (b)(1) If a main mine fan monitoring system is used, a trained 
person designated by the operator shall--
    (i) At least once each day review the data provided by the fan 
monitoring system to assure that the fan and the fan monitoring system 
are operating properly. No review is required on any day when no one, 
including certified persons, goes underground, except that a review of 
the data shall be performed prior to anyone entering the underground 
portion of the mine. Data reviewed should include the fan pressure, 
bearing temperature, revolutions per minute, vibration, electric 
voltage, and amperage; and
    (ii) At least every 7 days--
    (A) Test the monitoring system for proper operation; and
    (B) Examine each main mine fan and its associated components to 
assure electrical and mechanical reliability of main mine fans.
    (2) If the monitoring system malfunctions, the malfunction shall be 
corrected, or paragraph (a) of this section shall apply.
    (c) At least every 31 days, the automatic fan signal device for 
each main mine fan shall be tested by stopping the fan. Only persons 

[[Page 9831]]
necessary to evaluate the effect of the fan stoppage or restart, or to 
perform maintenance or repair work that cannot otherwise be made while 
the fan is operating, shall be permitted underground. Notwithstanding 
the requirement of Sec. 75.311(b)(3), underground power may remain 
energized during this test provided no one, including persons 
identified in Sec. 75.311(b)(1), is underground. If the fan is not 
restarted within 15 minutes, underground power shall be deenergized and 
no one shall enter any underground area of the mine until the fan is 
restarted and an examination of the mine is conducted as described in 
Sec. 75.360 (b) through (e) and the mine has been determined to be 
safe.
    (d) At least every 31 days, the automatic closing doors in multiple 
main mine fan systems shall be tested by stopping the fan. Only persons 
necessary to evaluate the effect of the fan stoppage or restart, or to 
perform maintenance or repair work that cannot otherwise be made while 
the fan is operating, shall be permitted underground. Notwithstanding 
the provisions of Sec. 75.311, underground power may remain energized 
during this test provided no one, including persons identified in 
Sec. 75.311(b)(1), is underground. If the fan is not restarted within 
15 minutes, underground power shall be deenergized and no one shall 
enter any underground area of the mine, until the fan is restarted and 
an examination of the mine is conducted as described in Sec. 75.360 (b) 
through (e) and the mine has been determined to be safe.
    (e) Circular main mine fan pressure recording charts shall be 
changed before the beginning of a second revolution.
    (f)(1) Certification. Persons making main mine fan examinations 
shall certify by initials and date at the fan or another location 
specified by the operator that the examinations were made. Each 
certification shall identify the main mine fan examined.
    (2) Persons reviewing data produced by a main mine fan monitoring 
system shall certify by initials and date on a printed copy of the data 
from the system that the review was completed. In lieu of certification 
on a copy of the data, the person reviewing the data may certify 
electronically that the review was completed. Electronic certification 
shall be by handwritten initials and date in a computer system so as to 
be secure and not susceptible to alteration.
    (g)(1) Recordkeeping. By the end of the shift on which the 
examination is made, persons making main mine fan examinations shall 
record all uncorrected defects that may affect the operation of the fan 
that are not corrected by the end of that shift. Records shall be 
maintained in a secure book that is not susceptible to alteration or 
electronically in a computer system so as to be secure and not 
susceptible to alteration.
    (2) When a fan monitoring system is used in lieu of the daily fan 
examination--
    (i) The certified copies of data produced by fan monitoring systems 
shall be maintained separate from other computer-generated reports or 
data; and
    (ii) A record shall be made of any fan monitoring system 
malfunctions, electrical or mechanical deficiencies in the monitoring 
system and any sudden increase or loss in mine ventilating pressure. 
The record shall be made by the end of the shift on which the review of 
the data is completed and shall be maintained in a secure book that is 
not susceptible to alteration or electronically in a computer system so 
as to be secure and not susceptible to alteration.
    (3) By the end of the shift on which the monthly test of the 
automatic fan signal device or the automatic closing doors is 
completed, persons making these tests shall record the results of the 
tests. Records shall be maintained in a secure book that is not 
susceptible to alteration or electronically in a computer system so as 
to be secure and not susceptible to alteration.
    (h) Retention period. Records, including records of mine fan 
pressure and the certified copies of data produced by fan monitoring 
systems, shall be retained at a surface location at the mine for at 
least 1 year and shall be made available for inspection by authorized 
representatives of the Secretary and the representative of miners.


Sec. 75.313  Main mine fan stoppage with persons underground.

    (a) If a main mine fan stops while anyone is underground and the 
ventilating quantity provided by the fan is not maintained by a back-up 
fan system--
    (1) Electrically powered equipment in each working section shall be 
deenergized;
    (2) Other mechanized equipment in each working section shall be 
shut off; and
    (3) Everyone shall be withdrawn from the working sections and areas 
where mechanized mining equipment is being installed or removed.
    (b) If ventilation is restored within 15 minutes after a main mine 
fan stops, certified persons shall examine for methane in the working 
places and in other areas where methane is likely to accumulate before 
work is resumed and before equipment is energized or restarted in these 
areas.
    (c) If ventilation is not restored within 15 minutes after a main 
mine fan stops--
    (1) Everyone shall be withdrawn from the mine;
    (2) Underground electric power circuits shall be deenergized. 
However, circuits necessary to withdraw persons from the mine need not 
be deenergized if located in areas or haulageways where methane is not 
likely to migrate to or accumulate. These circuits shall be deenergized 
as persons are withdrawn; and
    (3) Mechanized equipment not located on working sections shall be 
shut off. However, mechanized equipment necessary to withdraw persons 
from the mine need not be shut off if located in areas where methane is 
not likely to migrate to or accumulate.
    (d)(1) When ventilation is restored--
    (i) No one other than designated certified examiners shall enter 
any underground area of the mine until an examination is conducted as 
described in Sec. 75.360(b) through (e) and the area has been 
determined to be safe. Designated certified examiners shall enter the 
underground area of the mine from which miners have been withdrawn only 
after the fan has operated for at least 15 minutes unless a longer 
period of time is specified in the approved ventilation plan.
    (ii) Underground power circuits shall not be energized and 
nonpermissible mechanized equipment shall not be started or operated in 
an area until an examination is conducted as described in 
Sec. 75.360(b) through (e) and the area has been determined to be safe, 
except that designated certified examiners may use nonpermissible 
transportation equipment in intake airways to facilitate the making of 
the required examination.
    (2) If ventilation is restored to the mine before miners reach the 
surface, the miners may return to underground working areas only after 
an examination of the areas is made by a certified person and the areas 
are determined to be safe.
    (e) Any atmospheric monitoring system operated during fan stoppages 
shall be intrinsically safe.


Sec. 75.320  Air quality detectors and measurement devices.

    (a) Tests for methane shall be made by a qualified person with MSHA 
approved detectors that are maintained in permissible and proper 
operating condition and calibrated with a known 

[[Page 9832]]
methane-air mixture at least once every 31 days.
    (b) Tests for oxygen deficiency shall be made by a qualified person 
with MSHA approved oxygen detectors that are maintained in permissible 
and proper operating condition and that can detect 19.5 percent oxygen 
with an accuracy of <plus-minus>0.5 percent. The oxygen detectors shall 
be calibrated at the start of each shift that the detectors will be 
used.
    (c) Handheld devices that contain electrical components and that 
are used for measuring air velocity, carbon monoxide, oxides of 
nitrogen, and other gases shall be approved and maintained in 
permissible and proper operating condition.
    (d) An oxygen detector approved by MSHA shall be used to make tests 
for oxygen deficiency required by the regulations in this part. 
Permissible flame safety lamps may only be used as a supplementary 
testing device.
    (e) Maintenance of instruments required by paragraphs (a) through 
(d) of this section shall be done by persons trained in such 
maintenance.


Sec. 75.321  Air quality.

    (a)(1) The air in areas where persons work or travel, except as 
specified in paragraph (a)(2) of this section, shall contain at least 
19.5 percent oxygen and not more than 0.5 percent carbon dioxide, and 
the volume and velocity of the air current in these areas shall be 
sufficient to dilute, render harmless, and carry away flammable, 
explosive, noxious, and harmful gases, dusts, smoke, and fumes.
    (2) The air in areas of bleeder entries and worked-out areas where 
persons work or travel shall contain at least 19.5 percent oxygen, and 
carbon dioxide levels shall not exceed 0.5 percent time weighted 
average and 3.0 percent short term exposure limit.
    (b) Notwithstanding the provisions of Sec. 75.322, for the purpose 
of preventing explosions from gases other than methane, the following 
gases shall not be permitted to accumulate in excess of the 
concentrations listed below:
    (1) Carbon monoxide (CO)--2.5 percent
    (2) Hydrogen (H<INF>2)--.80 percent
    (3) Hydrogen sulfide (H<INF>2S)--.80 percent
    (4) Acetylene (C<INF>2H<INF>2)--.40 percent
    (5) Propane (C<INF>3H<INF>8)--.40 percent
    (6) MAPP (methyl-acetylene-propylene-propodiene)--.30 percent


Sec. 75.322  Harmful quantities of noxious gases.

    Concentrations of noxious or poisonous gases, other than carbon 
dioxide, shall not exceed the current threshold limit values (TLV) as 
specified and applied by the ACGIH. Detectors or laboratory analysis of 
mine air samples shall be used to determine the concentrations of 
harmful, noxious, or poisonous gases.


Sec. 75.323  Actions for excessive methane.

    (a) Location of tests. Tests for methane concentrations under this 
section shall be made at least 12 inches from the roof, face, ribs, and 
floor.
    (b) Working places and intake air courses.
    (1) When 1.0 percent or more methane is present in a working place 
or an intake air course, including an air course in which a belt 
conveyor is located, or in an area where mechanized mining equipment is 
being installed or removed--
    (i) Except intrinsically safe atmospheric monitoring systems (AMS), 
electrically powered equipment in the affected area shall be 
deenergized, and other mechanized equipment shall be shut off;
    (ii) Changes or adjustments shall be made at once to the 
ventilation system to reduce the concentration of methane to less than 
1.0 percent; and
    (iii) No other work shall be permitted in the affected area until 
the methane concentration is less than 1.0 percent.
    (2) When 1.5 percent or more methane is present in a working place 
or an intake air course, including an air course in which a belt 
conveyor is located, or in an area where mechanized mining equipment is 
being installed or removed--
    (i) Everyone except those persons referred to in Sec. 104(c) of the 
Act shall be withdrawn from the affected area; and
    (ii) Except for intrinsically safe AMS, electrically powered 
equipment in the affected area shall be disconnected at the power 
source.
    (c) Return air split. (1) When 1.0 percent or more methane is 
present in a return air split between the last working place on a 
working section and where that split of air meets another split of air, 
or the location at which the split is used to ventilate seals or 
worked-out areas changes or adjustments shall be made at once to the 
ventilation system to reduce the concentration of methane in the return 
air to less than 1.0 percent.
    (2) When 1.5 percent or more methane is present in a return air 
split between the last working place on a working section and where 
that split of air meets another split of air, or the location where the 
split is used to ventilate seals or worked-out areas--
    (i) Everyone except those persons referred to in Sec. 104(c) of the 
Act shall be withdrawn from the affected area;
    (ii) Other than intrinsically safe AMS, equipment in the affected 
area shall be deenergized, electric power shall be disconnected at the 
power source, and other mechanized equipment shall be shut off; and
    (iii) No other work shall be permitted in the affected area until 
the methane concentration in the return air is less than 1.0 percent.
    (d) Return air split alternative. (1) The provisions of this 
paragraph apply if--
    (i) The quantity of air in the split ventilating the active 
workings is at least 27,000 cubic feet per minute in the last open 
crosscut or the quantity specified in the approved ventilation plan, 
whichever is greater;
    (ii) The methane content of the air in the split is continuously 
monitored during mining operations by an AMS that gives a visual and 
audible signal on the working section when the methane in the return 
air reaches 1.5 percent, and the methane content is monitored as 
specified in Sec. 75.351; and
    (iii) Rock dust is continuously applied with a mechanical duster to 
the return air course during coal production at a location in the air 
course immediately outby the most inby monitoring point.
    (2) When 1.5 percent or more methane is present in a return air 
split between a point in the return opposite the section loading point 
and where that split of air meets another split of air or where the 
split of air is used to ventilate seals or worked-out areas--
    (i) Changes or adjustments shall be made at once to the ventilation 
system to reduce the concentration of methane in the return air below 
1.5 percent;
    (ii) Everyone except those persons referred to in Sec. 104(c) of 
the Act shall be withdrawn from the affected area;
    (iii) Except for intrinsically safe AMS, equipment in the affected 
area shall be deenergized, electric power shall be disconnected at the 
power source, and other mechanized equipment shall be shut off; and
    (iv) No other work shall be permitted in the affected area until 
the methane concentration in the return air is less than 1.5 percent.
    (e) Bleeders and other return air courses. The concentration of 
methane in a bleeder split of air immediately before the air in the 
split joins another split of air, or in a return air course other than 
as described in paragraphs (c) and (d) of this section, shall not 
exceed 2.0 percent.

[[Page 9833]]



Sec. 75.324  Intentional changes in the ventilation system.

    (a) A person designated by the operator shall supervise any 
intentional change in ventilation that--
    (1) Alters the main air current or any split of the main air 
current in a manner that could materially affect the safety or health 
of persons in the mine; or
    (2) Affects section ventilation by 9,000 cubic feet per minute of 
air or more in bituminous or lignite mines, or 5,000 cubic feet per 
minute of air or more in anthracite mines.
    (b) Intentional changes shall be made only under the following 
conditions:
    (1) Electric power shall be removed from areas affected by the 
ventilation change and mechanized equipment in those areas shall be 
shut off before the ventilation change begins.
    (2) Only persons making the change in ventilation shall be in the 
mine.
    (3) Electric power shall not be restored to the areas affected by 
the ventilation change and mechanized equipment shall not be restarted 
until a certified person has examined these areas for methane 
accumulation and for oxygen deficiency and has determined that the 
areas are safe.


Sec. 75.325  Air quantity.

    (a)(1) In bituminous and lignite mines the quantity of air shall be 
at least 3,000 cubic feet per minute reaching each working face where 
coal is being cut, mined, drilled for blasting, or loaded. When a 
greater quantity is necessary to dilute, render harmless, and carry 
away flammable, explosive, noxious, and harmful gases, dusts, smoke, 
and fumes, this quantity shall be specified in the approved ventilation 
plan. A minimum air quantity may be required to be specified in the 
approved ventilation plan for other working places or working faces.
    (2) The quantity of air reaching the working face shall be 
determined at or near the face end of the line curtain, ventilation 
tubing, or other ventilation control device. If the curtain, tubing, or 
device extends beyond the last row of permanent roof supports, the 
quantity of air reaching the working face shall be determined behind 
the line curtain or in the ventilation tubing at or near the last row 
of permanent supports.
    (3) If machine mounted dust collectors or diffuser fans are used, 
the approved ventilation plan shall specify the operating volume of the 
dust collector or diffuser fan.
    (b) In bituminous and lignite mines, the quantity of air reaching 
the last open crosscut of each set of entries or rooms on each working 
section and the quantity of air reaching the intake end of a pillar 
line shall be at least 9,000 cubic feet per minute unless a greater 
quantity is required to be specified in the approved ventilation plan.
    (c) In longwall and shortwall mining systems--
    (1) The quantity of air shall be at least 30,000 cubic feet per 
minute reaching the working face of each longwall, unless the operator 
demonstrates that a lesser air quantity will maintain continual 
compliance with applicable methane and respirable dust standards. This 
lesser quantity shall be specified in the approved ventilation plan. A 
quantity greater than 30,000 cubic feet per minute may be required to 
be specified in the approved ventilation plan.
    (2) The velocity of air that will be provided to control methane 
and respirable dust below applicable standards on each longwall or 
shortwall and the locations where these velocities will be provided 
shall be specified in the approved ventilation plan. The locations 
specified shall be at least 50 feet but no more than 100 feet from the 
headgate and tailgate, respectively.
    (d) Ventilation shall be maintained during installation and removal 
of mechanized mining equipment. The approved ventilation plan shall 
specify the minimum quantity of air, the locations where this quantity 
will be provided and the ventilation controls required.
    (e) In anthracite mines, the quantity of air shall be as follows:
    (1) At least 1,500 cubic feet per minute reaching each working face 
where coal is being mined, unless a greater quantity is required to be 
specified in the approved ventilation plan.
    (2) At least 5,000 cubic feet per minute passing through the last 
open crosscut in each set of entries or rooms and at the intake end of 
any pillar line, unless a greater quantity is required to be specified 
in the approved ventilation plan.
    (3) When robbing areas where air currents cannot be controlled and 
air measurements cannot be obtained, the air shall have perceptible 
movement.


Sec. 75.326  Mean entry air velocity.

    In exhausting face ventilation systems, the mean entry air velocity 
shall be at least 60 feet per minute reaching each working face where 
coal is being cut, mined, drilled for blasting, or loaded, and to any 
other working places as required in the approved ventilation plan. A 
lower mean entry air velocity may be approved in the ventilation plan 
if the lower velocity will maintain methane and respirable dust 
concentrations below the applicable levels. Mean entry air velocity 
shall be determined at or near the inby end of the line curtain, 
ventilation tubing, or other face ventilation control devices.


Sec. 75.327  Air courses and trolley haulage systems.

    (a) In any mine opened on or after March 30, 1970, or in any new 
working section of a mine opened before that date, where trolley 
haulage systems are maintained and where trolley wires or trolley 
feeder wires are installed, an authorized representative of the 
Secretary shall require enough entries or rooms as intake air courses 
to limit the velocity of air currents in the haulageways to minimize 
the hazards of fires and dust explosions in the haulageways.
    (b) Unless the district manager approves a higher velocity, the 
velocity of the air current in the trolley haulage entries shall be 
limited to not more than 250 feet per minute. A higher air velocity may 
be required to limit the methane content in these haulage entries or 
elsewhere in the mine to less than 1.0 percent and provide an adequate 
supply of oxygen.


Sec. 75.330  Face ventilation control devices.

    (a) Brattice cloth, ventilation tubing and other face ventilation 
control devices shall be made of flame-resistant material approved by 
MSHA.
    (b)(1) Ventilation control devices shall be used to provide 
ventilation to dilute, render harmless, and to carry away flammable, 
explosive, noxious, and harmful gases, dusts, smoke, and fumes--
    (i) To each working face from which coal is being cut, mined, 
drilled for blasting, or loaded; and
    (ii) To any other working places as required by the approved 
ventilation plan.
    (2) These devices shall be installed at a distance no greater than 
10 feet from the area of deepest penetration to which any portion of 
the face has been advanced unless an alternative distance is specified 
and approved in the ventilation plan. Alternative distances specified 
shall be capable of maintaining concentrations of respirable dust, 
methane, and other harmful gases below the levels specified in the 
applicable sections of this chapter.
    (c) When the line brattice or any other face ventilation control 
device is damaged to an extent that ventilation of the working face is 
inadequate, production activities in the working place shall cease 
until necessary repairs 

[[Page 9834]]
are made and adequate ventilation is restored.


Sec. 75.331  Auxiliary fans and tubing.

    (a) When auxiliary fans and tubing are used for face ventilation, 
each auxiliary fan shall be--
    (1) Permissible, if the fan is electrically operated;
    (2) Maintained in proper operating condition;
    (3) Deenergized or shut off when no one is present on the working 
section; and
    (4) Located and operated to avoid recirculation of air.
    (b) If a deficiency exists in any auxiliary fan system, the 
deficiency shall be corrected or the auxiliary fan shall be deenergized 
immediately.
    (c) If the air passing through an auxiliary fan or tubing contains 
1.0 percent or more methane, power to electrical equipment in the 
working place and to the auxiliary fan shall be deenergized, and other 
mechanized equipment in the working place shall be shut off until the 
methane concentration is reduced to less than 1.0 percent.
    (d) When an auxiliary fan is stopped--
    (1) Line brattice or other face ventilation control devices shall 
be used to maintain ventilation to affected faces; and
    (2) Electrical equipment in the affected working places shall be 
disconnected at the power source, and other mechanized equipment shall 
be shut off until ventilation to the working place is restored.


Sec. 75.332  Working sections and working places.

    (a)(1) Each working section and each area where mechanized mining 
equipment is being installed or removed, shall be ventilated by a 
separate split of intake air directed by overcasts, undercasts or other 
permanent ventilation controls.
    (2) When two or more sets of mining equipment are simultaneously 
engaged in cutting, mining, or loading coal or rock from working places 
within the same working section, each set of mining equipment shall be 
on a separate split of intake air.
    (3) For purposes of this section, a set of mining equipment 
includes a single loading machine, a single continuous mining machine, 
or a single longwall or shortwall mining machine.
    (b)(1) Air that has passed through any area that is not examined 
under Secs. 75.360, 75.361 or 75.364 of this subpart, or through an 
area where second mining has been done shall not be used to ventilate 
any working place. Second mining is intentional retreat mining where 
pillars have been wholly or partially removed, regardless of the amount 
of recovery obtained.
    (2) Air that has passed by any opening of any unsealed area that is 
not examined under Secs. 75.360, 75.361 or 75.364 of this subpart, 
shall not be used to ventilate any working place.


Sec. 75.333  Ventilation controls.

    (a) For purposes of this section, ``doors'' include any door 
frames.
    (b) Permanent stoppings or other permanent ventilation control 
devices constructed after November 15, 1992, shall be built and 
maintained--
    (1) Between intake and return air courses, except temporary 
controls may be used in rooms that are 600 feet or less from the 
centerline of the entry from which the room was developed including 
where continuous face haulage systems are used in such rooms. Unless 
otherwise approved in the ventilation plan, these stoppings or controls 
shall be maintained to and including the third connecting crosscut 
outby the working face;
    (2) To separate belt conveyor haulageways from return air courses, 
except where belt entries in areas of mines developed before March 30, 
1970, are used as return air courses;
    (3) To separate belt conveyor haulageways from intake air courses 
when the air in the intake air courses is used to provide air to active 
working places. Temporary ventilation controls may be used in rooms 
that are 600 feet or less from the centerline of the entry from which 
the rooms were developed including where continuous face haulage 
systems are used in such rooms. When continuous face haulage systems 
are used, permanent stoppings or other permanent ventilation control 
devices shall be built and maintained to the outby most point of travel 
of the dolly or 600 feet from the point of deepest penetration in the 
conveyor belt entry, whichever distance is closer to the point of 
deepest penetration, to separate the continuous haulage entry from the 
intake entries;
    (4) To separate the primary escapeway from belt and trolley haulage 
entries, as required by Sec. 75.380(g). For the purposes of 
Sec. 75.380(g), the loading point for a continuous haulage system shall 
be the outby most point of travel of the dolly or 600 feet from the 
point of deepest penetration, whichever distance is less; and
    (5) In return air courses to direct air into adjacent worked-out 
areas.
    (c) Personnel doors shall be constructed of noncombustible material 
and shall be of sufficient strength to serve their intended purpose of 
maintaining separation and permitting travel between air courses, and 
shall be installed as follows in permanent stoppings constructed after 
November 15, 1992:
    (1) The distance between personnel doors shall be no more than 300 
feet in seam heights below 48 inches and 600 feet in seam heights 48 
inches or higher.
    (2) The location of all personnel doors in stoppings along 
escapeways shall be clearly marked so that the doors may be easily 
identified by anyone traveling in the escapeway and in the entries on 
either side of the doors.
    (3) When not in use, personnel doors shall be closed.
    (d) Doors, other than personnel doors, constructed after November 
15, 1992, that are used in lieu of permanent stoppings or to control 
ventilation within an air course shall be:
    (1) Made of noncombustible material or coated on all accessible 
surfaces with flame-retardant material having a flame-spread index of 
25 or less, as tested under ASTM E162-87.
    (2) Of sufficient strength to serve their intended purpose of 
maintaining separation and permitting travel between or within air 
courses or entries.
    (3) Installed in pairs to form an airlock. When an airlock is used, 
one side of the airlock shall remain closed. When not in use, both 
sides shall be closed.
    (e)(1)(i) Except as provided in paragraphs (e)(2), (e)(3) and 
(e)(4) of this section all overcasts, undercasts, shaft partitions, 
permanent stoppings, and regulators, installed after March 11, 1997, 
shall be constructed in a traditionally accepted method and of 
materials that have been demonstrated to perform adequately or in a 
method and of materials that have been tested and shown to have a 
minimum strength equal to or greater than the traditionally accepted 
in-mine controls. Tests may be performed under ASTM E72-80 Section 12--
Transverse Load-Specimen Vertical, load only, or the operator may 
conduct comparative in-mine tests. In-mine tests shall be designed to 
demonstrate the comparative strength of the proposed construction and a 
traditionally accepted in-mine control.
    (ii) All overcasts, undercasts, shaft partitions, permanent 
stoppings, and regulators, installed after November 15, 1992, shall be 
constructed of noncombustible material. Materials that are suitable for 
the construction of overcasts, undercasts, shaft partitions, permanent 
stoppings, and regulators include concrete, concrete block, brick, 
cinder block, tile, or steel. No ventilation controls installed after 

[[Page 9835]]
November 15, 1992, shall be constructed of aluminum.
    (2) In anthracite mines, permanent stoppings may be constructed of 
overlapping layers of hardwood mine boards, if the stoppings are a 
minimum 2 inches thick.
    (3) When timbers are used to create permanent stoppings in heaving 
or caving areas, the stoppings shall be coated on all accessible 
surfaces with a flame-retardant material having a flame-spread index of 
25 or less, as tested under ASTM E162-87, ``Surface Flammability of 
Materials Using a Radiant Heat Energy Source.''
    (4) In anthracite mines, doors and regulators may be constructed of 
overlapping layers of hardwood boards, if the doors, door frames, and 
regulators are a minimum 2 inches thick.
    (f) When sealants are applied to ventilation controls, the sealant 
shall have a flame-spread index of 25 or less under ASTM E162-87.
    (g) Before mining is discontinued in an entry or room that is 
advanced more than 20 feet from the inby rib, a crosscut shall be made 
or line brattice shall be installed and maintained to provide adequate 
ventilation. When conditions such as methane liberation warrant a 
distance less than 20 feet, the approved ventilation plan shall specify 
the location of such rooms or entries and the maximum distance they 
will be developed before a crosscut is made or line brattice is 
installed.
    (h) All permanent ventilation controls, including seals, shall be 
maintained to serve the purpose for which they were built.


Sec. 75.334  Worked-out areas and areas where pillars are being 
recovered.

    (a) Worked-out areas where no pillars have been recovered shall 
be--
    (1) Ventilated so that methane-air mixtures and other gases, dusts, 
and fumes from throughout the worked-out areas are continuously diluted 
and routed into a return air course or to the surface of the mine; or
    (2) Sealed.
    (b)(1) During pillar recovery a bleeder system shall be used to 
control the air passing through the area and to continuously dilute and 
move methane-air mixtures and other gases, dusts, and fumes from the 
worked-out area away from active workings and into a return air course 
or to the surface of the mine.
    (2) After pillar recovery a bleeder system shall be maintained to 
provide ventilation to the worked-out area, or the area shall be 
sealed.
    (c) The approved ventilation plan shall specify the following:
    (1) The design and use of bleeder systems;
    (2) The means to determine the effectiveness of bleeder systems;
    (3) The means for adequately maintaining bleeder entries free of 
obstructions such as roof falls and standing water; and
    (4) The location of ventilating devices such as regulators, 
stoppings and bleeder connectors used to control air movement through 
the worked-out area.
    (d) If the bleeder system used does not continuously dilute and 
move methane-air mixtures and other gases, dusts, and fumes away from 
worked-out areas into a return air course or to the surface of the 
mine, or it cannot be determined by examinations or evaluations under 
Sec. 75.364 that the bleeder system is working effectively, the worked-
out area shall be sealed.
    (e) Each mining system shall be designed so that each worked-out 
area can be sealed. The approved ventilation plan shall specify the 
location and the sequence of construction of proposed seals.
    (f) In place of the requirements of paragraphs (a) and (b) of this 
section, for mines with a demonstrated history of spontaneous 
combustion, or that are located in a coal seam determined to be 
susceptible to spontaneous combustion, the approved ventilation plan 
shall specify the following:
    (1) Measures to detect methane, carbon monoxide, and oxygen 
concentrations during and after pillar recovery, and in worked-out 
areas where no pillars have been recovered, to determine if the areas 
must be ventilated or sealed.
    (2) Actions that will be taken to protect miners from the hazards 
of spontaneous combustion.
    (3) If a bleeder system will not be used, the methods that will be 
used to control spontaneous combustion, accumulations of methane-air 
mixtures, and other gases, dusts, and fumes in the worked-out area.


Sec. 75.335  Construction of seals.

    (a)(1) Each seal constructed after November 15, 1992, shall be--
    (i) Constructed of solid concrete blocks at least 6 by 8 by 16 
inches, laid in a transverse pattern with mortar between all joints;
    (ii) Hitched into solid ribs to a depth of at least 4 inches and 
hitched at least 4 inches into the floor;
    (iii) At least 16 inches thick. When the thickness of the seal is 
less than 24 inches and the width is greater than 16 feet or the height 
is greater than 10 feet, a pilaster shall be interlocked near the 
center of the seal. The pilaster shall be at least 16 inches by 32 
inches; and
    (iv) Coated on all accessible surfaces with flame-retardant 
material that will minimize leakage and that has a flame-spread index 
of 25 or less, as tested under ASTM E162-87, ``Surface Flammability of 
Materials Using a Radiant Heat Energy Source.''
    (2) Alternative methods or materials may be used to create a seal 
if they can withstand a static horizontal pressure of 20 pounds per 
square inch provided the method of installation and the material used 
approved in the ventilation plan. If the alternative methods or 
materials include the use of timbers, the timbers also shall be coated 
on all accessible surfaces with flame-retardant material having a 
flame-spread index 25 or less, as tested under ASTM E162-87.
    (b) A sampling pipe or pipes shall be installed in each set of 
seals for a worked-out area. Each pipe shall--
    (1) Extend into the sealed area a sufficient distance (at least 15 
feet) to obtain a representative sample from behind the seal;
    (2) Be equipped with a cap or shut-off valve; and
    (3) Be installed with the sampling end of the pipe about 12 inches 
from the roof.
    (c)(1) A corrosion-resistant water pipe or pipes shall be installed 
in seals at the low points of the area being sealed and at all other 
locations necessary when water accumulation within the sealed area is 
possible; and
    (2) Each water pipe shall have a water trap installed on the outby 
side of the seal.


Sec. 75.340  Underground electrical installations.

    (a) Underground transformer stations, battery charging stations, 
substations, rectifiers, and water pumps shall be housed in 
noncombustible structures or areas or be equipped with a fire 
suppression system meeting the requirements of Sec. 75.1107-3 through 
Sec. 75.1107-16.
    (1) When a noncombustible structure or area is used, these 
installations shall be--
    (i) Ventilated with intake air that is coursed into a return air 
course or to the surface and that is not used to ventilate working 
places; or
    (ii) Ventilated with intake air that is monitored for carbon 
monoxide or smoke by an AMS installed and operated according to 
Sec. 75.351. Monitoring of intake air ventilating battery charging 
stations shall be done with sensors not affected by hydrogen; or
    (iii) Ventilated with intake air and equipped with sensors to 
monitor for heat and for carbon monoxide or smoke. Monitoring of intake 
air ventilating battery charging stations shall be done 

[[Page 9836]]
with sensors not affected by hydrogen. The sensors shall deenergize 
power to the installation, activate a visual and audible alarm located 
outside of and on the intake side of the enclosure, and activate doors 
that will automatically close when either of the following occurs:
    (A) The temperature in the noncombustible structure reaches 165 
deg.F; or
    (B) The carbon monoxide concentration reaches 10 parts per million 
above the ambient level for the area, or the optical density of smoke 
reaches 0.022 per meter. At least every 31 days, sensors installed to 
monitor for carbon monoxide shall be calibrated with a known 
concentration of carbon monoxide and air sufficient to activate the 
closing door, or each smoke sensor shall be tested to determine that it 
functions correctly.
    (2) When a fire suppression system is used, these installations 
shall be--
    (i) Ventilated with intake air that is coursed into a return air 
course or to the surface and that is not used to ventilate working 
places; or
    (ii) Ventilated with intake air that is monitored for carbon 
monoxide or smoke by an AMS installed and operated according to 
Sec. 75.351. Monitoring of intake air ventilating battery charging 
stations shall be done with sensors not affected by hydrogen.
    (b) This section does not apply to--
    (1) Rectifiers and power centers with transformers that are either 
dry-type or contain nonflammable liquid, if they are located at or near 
the section and are moved as the working section advances or retreats;
    (2) Submersible pumps;
    (3) Permissible pumps and associated permissible switchgear;
    (4) Pumps located on or near the section and that are moved as the 
working section advances or retreats;
    (5) Pumps installed in anthracite mines; and
    (6) Small portable pumps.


Sec. 75.341  Direct-fired intake air heaters.

    (a) If any system used to heat intake air malfunctions, the heaters 
affected shall switch off automatically.
    (b) Thermal overload devices shall protect the blower motor from 
overheating.
    (c) The fuel supply shall turn off automatically if a flame-out 
occurs.
    (d) Each heater shall be located or guarded to prevent contact by 
persons and shall be equipped with a screen at the inlet to prevent 
combustible materials from passing over the burner units.
    (e) If intake air heaters use liquefied fuel systems--
    (1) Hydrostatic relief valves installed on vaporizers and on 
storage tanks shall be vented; and
    (2) Fuel storage tanks shall be located or protected to prevent 
fuel from leaking into the mine.
    (f) Following any period of 8 hours or more during which a heater 
does not operate, the heater and its associated components shall be 
examined within its first hour of operation. Additionally, each heater 
and its components shall be examined at least once each shift that the 
heater operates. The examination shall include measurement of the 
carbon monoxide concentration at the bottom of each shaft, slope, or in 
the drift opening where air is being heated. The measurements shall be 
taken by a person designated by the operator or by a carbon monoxide 
sensor that is calibrated with a known concentration of carbon monoxide 
and air at least once every 31 days. When the carbon monoxide 
concentration at this location reaches 50 parts per million, the heater 
causing the elevated carbon monoxide level shall be shut down.


Sec. 75.342  Methane monitors.

    (a)(1) MSHA approved methane monitors shall be installed on all 
face cutting machines, continuous miners, longwall face equipment, 
loading machines, and other mechanized equipment used to extract or 
load coal within the working place.
    (2) The sensing device for methane monitors on longwall shearing 
machines shall be installed at the return air end of the longwall face. 
An additional sensing device also shall be installed on the longwall 
shearing machine, downwind and as close to the cutting head as 
practicable. An alternative location or locations for the sensing 
device required on the longwall shearing machine may be approved in the 
ventilation plan.
    (3) The sensing devices of methane monitors shall be installed as 
close to the working face as practicable.
    (4) Methane monitors shall be maintained in permissible and proper 
operating condition and shall be calibrated with a known air-methane 
mixture at least once every 31 days. To assure that methane monitors 
are properly maintained and calibrated, the operator shall:
    (i) Use persons properly trained in the maintenance, calibration, 
and permissibility of methane monitors to calibrate and maintain the 
devices.
    (ii) Maintain a record of all calibration tests of methane 
monitors. Records shall be maintained in a secure book that is not 
susceptible to alteration or electronically in a computer system so as 
to be secure and not susceptible to alteration.
    (iii) Retain the record of calibration tests for 1 year from the 
date of the test. Records shall be retained at a surface location at 
the mine and made available for inspection by authorized 
representatives of the Secretary and the representative of miners.
    (b)(1) When the methane concentration at any methane monitor 
reaches 1.0 percent the monitor shall give a warning signal.
    (2) The warning signal device of the methane monitor shall be 
visible to a person who can deenergize the equipment on which the 
monitor is mounted.
    (c) The methane monitor shall automatically deenergize the machine 
on which it is mounted when--
    (1) The methane concentration at any methane monitor reaches 2.0 
percent; or
    (2) The monitor is not operating properly.


Sec. 75.343  Underground shops.

    (a) Underground shops shall be equipped with an automatic fire 
suppression system meeting the requirements of Sec. 75.1107-3 through 
Sec. 75.1107-16, or be enclosed in a noncombustible structure or area.
    (b) Underground shops shall be ventilated with intake air that is 
coursed directly into a return air course.


Sec. 75.344  Compressors.

    (a) Except compressors that are components of equipment such as 
locomotives and rock dusting machines and compressors of less than 5 
horsepower, electrical compressors including those that may start 
automatically shall be:
    (1) Continuously attended by a person designated by the operator 
who can see the compressor at all times during its operation. Any 
designated person attending the compressor shall be capable of 
activating the fire suppression system and deenergizing or shutting-off 
the compressor in the event of a fire; or,
    (2) Enclosed in a noncombustible structure or area which is 
ventilated by intake air coursed directly into a return air course or 
to the surface and equipped with sensors to monitor for heat and for 
carbon monoxide or smoke. The sensors shall deenergize power to the 
compressor, activate a visual and audible alarm located outside of and 
on the intake side of the enclosure, and activate doors to 
automatically enclose the noncombustible structure or area when either 
of the following occurs:
    (i) The temperature in the noncombustible structure or area reaches 
165  deg.F. 

[[Page 9837]]

    (ii) The carbon monoxide concentration reaches 10 parts per million 
above the ambient level for the area, or the optical density of smoke 
reaches 0.022 per meter. At least once every 31 days, sensors installed 
to monitor for carbon monoxide shall be calibrated with a known 
concentration of carbon monoxide and air sufficient to activate the 
closing door, and each smoke sensor shall be tested to determine that 
it functions correctly.
    (b) Compressors, except those exempted in paragraph (a), shall be 
equipped with a heat activated fire suppression system meeting the 
requirements of 75.1107-3 through 75.1107-16.
    (c) Two portable fire extinguishers or one extinguisher having at 
least twice the minimum capacity specified for a portable fire 
extinguisher in Sec. 75.1100-1(e) shall be provided for each 
compressor.
    (d) In addition to electrical compressors, this section shall apply 
to diesel compressors.
    (e) Notwithstanding the requirements of Sec. 75.1107-4, upon 
activation of any fire suppression system used under paragraph (b) of 
this section, the compressor shall be automatically deenergized or 
automatically shut off.


Sec. 75.350  Air courses and belt haulage entries.

    In any coal mine opened after March 30, 1970, the entries used as 
intake and return air courses shall be separated from belt haulage 
entries, and each operator of such mine shall limit the velocity of the 
air coursed through belt haulage entries to the amount necessary to 
provide an adequate supply of oxygen in such entries, and to insure 
that the air therein shall contain less than 1.0 volume per centum of 
methane, and such air shall not be used to ventilate active working 
places. Whenever an authorized representative of the Secretary finds, 
in the case of any coal mine opened on or prior to March 30, 1970, that 
has been developed with more than two entries, that the conditions in 
the entries, other than belt haulage entries, are such as to permit 
adequately the coursing of intake or return air through such entries:
    (a) The belt haulage entries shall not be used to ventilate, unless 
such entries are necessary to ventilate, active working places, and
    (b) When the belt haulage entries are not necessary to ventilate 
the active working places, the operator of such mine shall limit the 
velocity of the air coursed through the belt haulage entries to the 
amount necessary to provide an adequate supply of oxygen in such 
entries, and to assure that air therein shall contain less than 1.0 
volume per centum of methane.


Sec. 75.351  Atmospheric monitoring system (AMS).

    (a) Minimum requirements. An AMS shall consist of sensors to 
monitor the mine atmosphere and instruments at a surface location 
designated by the operator to receive information from the monitoring 
sensors. Each AMS installed in accordance with Secs. 75.323(d)(1)(ii), 
75.340(a)(2) and 75.362(f) shall do the following:
    (1) Monitor for circuit continuity and sensor function, and 
identify at the designated surface location any activated or 
malfunctioning sensor.
    (2) Signal a designated surface location at the mine when any 
interruption of circuit continuity occurs or any sensor malfunctions.
    (3) Signal affected working sections and the designated surface 
location when--
    (i) The carbon monoxide concentration at any carbon monoxide sensor 
reaches 5 parts per million above the established ambient level for 
that area; or
    (ii) The methane concentration at any methane monitoring station 
exceeds the maximum allowable concentration as specified for that 
location in Sec. 75.323.
    (4) Activate alarms at a designated surface location and affected 
working sections when the carbon monoxide concentration at any carbon 
monoxide sensor reaches 10 parts per million above the established 
ambient level for the area or when the optical density of smoke at any 
smoke sensor reaches 0.05 per meter.
    (b) Return splits. (1) If used to monitor return air splits under 
Sec. 75.362(f), AMS sensors shall monitor the mine atmosphere for 
percentage of methane in each return split of air from each working 
section between the last working place, or longwall or shortwall face, 
ventilated by that air split and the junction of that return air split 
with another air split, seal, or worked-out area. If auxiliary fans and 
tubing are used, the sensor also shall be located outby the auxiliary 
fan discharge.
    (2) If used to monitor air splits under Sec. 75.323(d)(1)(ii), AMS 
sensors shall monitor the mine atmosphere at the following locations:
    (i) In the return air course opposite the section loading point or, 
if auxiliary fans and tubing are used, in the return air course outby 
the auxiliary fans and a point opposite the section loading point.
    (ii) Immediately inby the location where the split of air meets 
another split of air, or inby the location where the split of air is 
used to ventilate seals or worked-out areas.
    (c) Electrical installations. If used to monitor the intake air 
ventilating underground transformer stations, battery charging 
stations, substations, rectifiers, or water pumps under 
Sec. 75.340(a)(2), at least one sensor shall be installed to monitor 
the mine atmosphere for carbon monoxide or smoke at least 50 feet and 
no more than 100 feet downstream in the direction of air flow.
    (d) Signals and alarms. (1) A person designated by the operator 
shall be at a surface location where the signals and alarms from the 
AMS can always be seen or heard while anyone is underground. This 
person shall have access to two-way communication with working sections 
and with other identifiable duty stations underground. A mine map 
showing the underground monitoring system shall be posted at the 
surface location.
    (2) If a signal from any AMS sensor is activated, the monitor 
producing the signal shall be identified, an examination shall be made 
to determine the cause of the activation, and appropriate action shall 
be taken.
    (e) Sensors. (1) Each carbon monoxide sensor shall be capable of 
detecting carbon monoxide in air at a level of <plus-minus>1 part per 
million throughout the operating range.
    (2) Each methane sensor shall be capable of detecting 1.0 percent 
methane in air with an accuracy of <plus-minus>0.2 percent methane.
    (3) Each smoke sensor shall be capable of detecting the optical 
density of smoke with an accuracy of <plus-minus>0.005 per meter.
    (f) Testing and calibration. At least once every 31 days--
    (1) Each carbon monoxide sensor shall be calibrated with a known 
concentration of carbon monoxide and air sufficient to activate an 
alarm;
    (2) Each smoke sensor shall be functionally tested;
    (3) Each methane sensor shall be calibrated with a known methane-
air mixture; and
    (4) Each oxygen sensor shall be calibrated with air having a known 
oxygen concentration.
    (g) Intrinsic Safety. Components of AMS installed in areas where 
permissible equipment is required shall be intrinsically safe.
    (h) Recordkeeping. If a signal device or alarm is activated, a 
record shall be made of the date, time, type of sensor, and the reason 
for its activation. Also the maximum concentration detected at 

[[Page 9838]]
the sensor producing the signal shall be recorded.
    (i) Retention period. Records shall be retained for at least 1 year 
at a surface location at the mine and made available for inspection by 
authorized representatives of the Secretary and representatives of 
miners.


Sec. 75.352  Return air courses.

    Entries used as return air courses shall be separated from belt 
haulage entries by permanent ventilation controls.


Sec. 75.360  Preshift examination.

    (a)(1) Except as provided in paragraph (a)(2) of this section, a 
certified person designated by the operator shall make a preshift 
examination within 3 hours preceding the beginning of any 8-hour 
interval during which any person is scheduled to work or travel 
underground. The operator shall establish the 8-hour intervals of time 
subject to the required preshift examinations. No person other than 
certified examiners may enter or remain in any underground area unless 
a preshift examination has been completed for the established 8-hour 
period.
    (2) Preshift examinations of areas where pumpers are scheduled to 
work or travel shall not be required prior to the pumper entering the 
areas if the pumper is a certified person and the pumper conducts an 
examination for hazardous conditions, tests for methane and oxygen 
deficiency and determines if the air is moving in its proper direction 
in the area where the pumper works or travels. The examination of the 
area must be completed before the pumper performs any other work. A 
record of all hazardous conditions found by the pumper shall be made 
and retained in accordance with Sec. 75.363.
    (b) The person conducting the preshift examination shall examine 
for hazardous conditions, test for methane and oxygen deficiency, and 
determine if the air is moving in its proper direction at the following 
locations:
    (1) Roadways, travelways and track haulageways where persons are 
scheduled, prior to the beginning of the preshift examination, to work 
or travel during the oncoming shift.
    (2) Belt conveyors that will be used to transport persons during 
the oncoming shift and the entries in which these belt conveyors are 
located.
    (3) Working sections and areas where mechanized mining equipment is 
being installed or removed, if anyone is scheduled to work on the 
section or in the area during the oncoming shift. The scope of the 
examination shall include the working places, approaches to worked-out 
areas and ventilation controls on these sections and in these areas, 
and the examination shall include tests of the roof, face and rib 
conditions on these sections and in these areas.
    (4) Approaches to worked-out areas along intake air courses and at 
the entries used to carry air into worked-out areas if the intake air 
passing the approaches is used to ventilate working sections where 
anyone is scheduled to work during the oncoming shift. The examination 
of the approaches to the worked-out areas shall be made in the intake 
air course immediately inby and outby each entry used to carry air into 
the worked-out area. An examination of the entries used to carry air 
into the worked-out areas shall be conducted at a point immediately 
inby the intersection of each entry with the intake air course.
    (5) Seals along intake air courses where intake air passes by a 
seal to ventilate working sections where anyone is scheduled to work 
during the oncoming shift.
    (6)(i) Entries and rooms developed after November 15, 1992, and 
developed more than 2 crosscuts off an intake air course without 
permanent ventilation controls where intake air passes through or by 
these entries or rooms to reach a working section where anyone is 
scheduled to work during the oncoming shift; and,
    (ii) Entries and rooms developed after November 15, 1992, and 
driven more than 20 feet off an intake air course without a crosscut 
and without permanent ventilation controls where intake air passes 
through or by these entries or rooms to reach a working section where 
anyone is scheduled to work during the oncoming shift.
    (7) Where unattended diesel equipment is to operate or areas where 
trolley wires or trolley feeder wires are to be or will remain 
energized during the oncoming shift.
    (8) High spots along intake air courses where methane is likely to 
accumulate, if equipment will be operated in the area during the shift.
    (9) Underground electrical installations referred to in 
Sec. 75.340(a), except those pumps listed in Sec. 75.340 (b)(2) through 
(b)(6), and areas where compressors subject to Sec. 75.344 are 
installed if the electrical installation or compressor is or will be 
energized during the shift.
    (10) Other areas where work or travel during the oncoming shift is 
scheduled prior to the beginning of the preshift examination.
    (c) The person conducting the preshift examination shall determine 
the volume of air entering each of the following areas if anyone is 
scheduled to work in the areas during the oncoming shift:
    (1) In the last open crosscut of each set of entries or rooms on 
each working section and areas where mechanized mining equipment is 
being installed or removed. The last open crosscut is the crosscut in 
the line of pillars containing the permanent stoppings that separate 
the intake air courses and the return air courses.
    (2) On each longwall or shortwall in the intake entry or entries at 
the intake end of the longwall or shortwall face immediately outby the 
face and the velocity of air at each end of the face at the locations 
specified in the approved ventilation plan.
    (3) At the intake end of any pillar line--
    (i) If a single split of air is used, in the intake entry furthest 
from the return air course, immediately outby the first open crosscut 
outby the line of pillars being mined; or
    (ii) If a split system is used, in the intake entries of each split 
immediately inby the split point.
    (d) The district manager may require the certified person to 
examine other areas of the mine or examine for other hazards during the 
preshift examination.
    (e) Certification. At each working place examined, the person doing 
the preshift examination shall certify by initials, date, and the time, 
that the examination was made. In areas required to be examined outby a 
working section, the certified person shall certify by initials, date, 
and the time at enough locations to show that the entire area has been 
examined.
    (f) Recordkeeping. A record of the results of each preshift 
examination, including a record of hazardous conditions and their 
locations found by the examiner during each examination and of the 
results and locations of air and methane measurements, shall be made on 
the surface before any persons, other than certified persons conducting 
examinations required by this subpart, enter any underground area of 
the mine. The results of methane tests shall be recorded as the 
percentage of methane measured by the examiner. The record shall be 
made by the certified person who made the examination or by a person 
designated by the operator. If the record is made by someone other than 
the examiner, the examiner shall verify the record by initials and date 
by or at the end of the shift for which the examination was made. A 
record shall also be made by a certified person of the action taken to 
correct hazardous conditions found during the preshift 

[[Page 9839]]
examination. All preshift and corrective action records shall be 
countersigned by the mine foreman or equivalent mine official by the 
end of the mine foreman's or equivalent mine official's next regularly 
scheduled working shift. The records required by this section shall be 
made in a secure book that is not susceptible to alteration or 
electronically in a computer system so as to be secure and not 
susceptible to alteration.
    (g) Retention period. Records shall be retained at a surface 
location at the mine for at least 1 year and shall be made available 
for inspection by authorized representatives of the Secretary and the 
representative of miners.


Sec. 75.361  Supplemental examination.

    (a) Except for certified persons conducting examinations required 
by this subpart, within 3 hours before anyone enters an area in which a 
preshift examination has not been made for that shift, a certified 
person shall examine the area for hazardous conditions, determine 
whether the air is traveling in its proper direction and at its normal 
volume, and test for methane and oxygen deficiency.
    (b) Certification. At each working place examined, the person 
making the supplemental examination shall certify by initials, date, 
and the time, that the examination was made. In areas required to be 
examined outby a working section, the certified person shall certify by 
initials, date, and the time at enough locations to show that the 
entire area has been examined.


Sec. 75.362  On-shift examination.

    (a) (1) At least once during each shift, or more often if necessary 
for safety, a certified person designated by the operator shall conduct 
an on-shift examination of each section where anyone is assigned to 
work during the shift and any area where mechanized mining equipment is 
being installed or removed during the shift. The certified person shall 
check for hazardous conditions, test for methane and oxygen deficiency, 
and determine if the air is moving in its proper direction.
    (2) A person designated by the operator shall conduct an 
examination to assure compliance with the respirable dust control 
parameters specified in the mine ventilation plan. In those instances 
when a shift change is accomplished without an interruption in 
production on a section, the examination shall be made anytime within 1 
hour of the shift change. In those instances when there is an 
interruption in production during the shift change, the examination 
shall be made before production begins on a section. Deficiencies in 
dust controls shall be corrected before production begins or resumes. 
The examination shall include air quantities and velocities, water 
pressures and flow rates, excessive leakage in the water delivery 
system, water spray numbers and orientations, section ventilation and 
control device placement, and any other dust suppression measures 
required by the ventilation plan. Additional measurements of the air 
velocity and quantity, water pressure and flow rates are not required 
if continuous monitoring of these controls is used and indicates that 
the dust controls are functioning properly.
    (b) During each shift that coal is produced, a certified person 
shall examine for hazardous conditions along each belt conveyor 
haulageway where a belt conveyor is operated. This examination may be 
conducted at the same time as the preshift examination of belt 
conveyors and belt conveyor haulageways, if the examination is 
conducted within 3 hours before the oncoming shift.
    (c) Persons conducting the on-shift examination shall determine at 
the following locations:
    (1) The volume of air in the last open crosscut of each set of 
entries or rooms on each section and areas where mechanized mining 
equipment is being installed or removed. The last open crosscut is the 
crosscut in the line of pillars containing the permanent stoppings that 
separate the intake air courses and the return air courses.
    (2) The volume of air on a longwall or shortwall, including areas 
where longwall or shortwall equipment is being installed or removed, in 
the intake entry or entries at the intake end of the longwall or 
shortwall.
    (3) The velocity of air at each end of the longwall or shortwall 
face at the locations specified in the approved ventilation plan.
    (4) The volume of air at the intake end of any pillar line--
    (i) Where a single split of air is used in the intake entry 
furthest from the return air course immediately outby the first open 
crosscut outby the line of pillars being mined; or
    (ii) Where a split system is used in the intake entries of each 
split immediately inby the split point.
    (d) (1) A qualified person shall make tests for methane--
    (i) At the start of each shift at each working place before 
electrically operated equipment is energized; and
    (ii) Immediately before equipment is energized, taken into, or 
operated in a working place; and
    (iii) At 20-minute intervals, or more often if required in the 
approved ventilation plan at specific locations, during the operation 
of equipment in the working place.
    (2) These methane tests shall be made at the face from under 
permanent roof support, using extendable probes or other acceptable 
means. When longwall or shortwall mining systems are used, these 
methane tests shall be made at the shearer, the plow, or the cutting 
head. When mining has been stopped for more than 20 minutes, methane 
tests shall be conducted prior to the start up of equipment.
    (e) If auxiliary fans and tubing are used, they shall be inspected 
frequently.
    (f) During each shift that coal is produced and at intervals not 
exceeding 4 hours, tests for methane shall be made by a certified 
person or by an atmospheric monitoring system (AMS) in each return 
split of air from each working section between the last working place, 
or longwall or shortwall face, ventilated by that split of air and the 
junction of the return air split with another air split, seal, or 
worked-out area. If auxiliary fans and tubing are used, the tests shall 
be made at a location outby the auxiliary fan discharge.
    (g) Certification. (1) The person conducting the on-shift 
examination in belt haulage entries shall certify by initials, date, 
and time that the examination was made. The certified person shall 
certify by initials, date, and the time at enough locations to show 
that the entire area has been examined.
    (2) The person directing the on-shift examination to assure 
compliance with the respirable dust control parameters specified in the 
mine ventilation plan shall certify by initials, date, and time that 
the examination was made.


Sec. 75.363  Hazardous conditions; posting, correcting and recording.

    (a) Any hazardous condition found by the mine foreman or equivalent 
mine official, assistant mine foreman or equivalent mine official, or 
other certified persons designated by the operator for the purposes of 
conducting examinations under this subpart D, shall be posted with a 
conspicuous danger sign where anyone entering the areas would pass. A 
hazardous condition, other than one detected during a preshift 
examination or an examination conducted following a fan stoppage and 
restart under Sec. 75.313(d)(1)(i), shall be corrected immediately or 
the area shall remain posted until the hazardous condition is 
corrected. If the condition creates an imminent danger, everyone except 
those persons referred to in 

[[Page 9840]]
section 104(c) of the Act shall be withdrawn from the area affected to 
a safe area until the hazardous condition is corrected. Only persons 
designated by the operator to correct or evaluate the condition may 
enter the posted area.
    (b) A record shall be made of any hazardous condition found. This 
record shall be kept in a book maintained for this purpose on the 
surface at the mine. The record shall be made by the completion of the 
shift on which the hazardous condition is found and shall include the 
nature and location of the hazardous condition and the corrective 
action taken. This record shall not be required for shifts when no 
hazardous conditions are found or for hazardous conditions found during 
the preshift or weekly examinations inasmuch as these examinations have 
separate recordkeeping requirements.
    (c) The record shall be made by the certified person who conducted 
the examination or a person designated by the operator. If made by a 
person other than the certified person, the certified person shall 
verify the record by initials and date by or at the end of the shift 
for which the examination was made. Records shall be countersigned by 
the mine foreman or equivalent mine official by the end of the mine 
foreman's or equivalent mine official's next regularly scheduled 
working shift. The record shall be made in a secure book that is not 
susceptible to alteration or electronically in a computer system so as 
to be secure and not susceptible to alteration.
    (d) Retention period. Records shall be retained at a surface 
location at the mine for at least 1 year and shall be made available 
for inspection by authorized representatives of the Secretary and the 
representative of miners.


Sec. 75.364  Weekly examination.

    (a) Worked-out areas. (1) At least every 7 days, a certified person 
shall examine unsealed worked-out areas where no pillars have been 
recovered by traveling to the area of deepest penetration; measuring 
methane and oxygen concentrations and air quantities and making tests 
to determine if the air is moving in the proper direction in the area. 
The locations of measurement points where tests and measurements will 
be performed shall be included in the mine ventilation plan and shall 
be adequate in number and location to assure ventilation and air 
quality in the area. Air quantity measurements shall also be made where 
the air enters and leaves the worked-out area. An alternative method of 
evaluating the ventilation of the area may be approved in the 
ventilation plan.
    (2) At least every 7 days, a certified person shall evaluate the 
effectiveness of bleeder systems required by Sec. 75.334 as follows:
    (i) Measurements of methane and oxygen concentrations and air 
quantity and a test to determine if the air is moving in its proper 
direction shall be made where air enters the worked-out area.
    (ii) Measurements of methane and oxygen concentrations and air 
quantity and a test to determine if the air is moving in the proper 
direction shall be made immediately before the air enters a return 
split of air.
    (iii) At least one entry of each set of bleeder entries used as 
part of a bleeder system under Sec. 75.334 shall be traveled in its 
entirety. Measurements of methane and oxygen concentrations and air 
quantities and a test to determine if the air is moving in the proper 
direction shall be made at the measurement point locations specified in 
the mine ventilation plan to determine the effectiveness of the bleeder 
system.
    (iv) In lieu of the requirements of paragraphs (a)(2)(i) and (iii) 
of this section, an alternative method of evaluation may be specified 
in the ventilation plan provided the alternative method results in 
proper evaluation of the effectiveness of the bleeder system.
    (b) Hazardous conditions. At least every 7 days, an examination for 
hazardous conditions at the following locations shall be made by a 
certified person designated by the operator:
    (1) In at least one entry of each intake air course, in its 
entirety, so that the entire air course is traveled.
    (2) In at least one entry of each return air course, in its 
entirety, so that the entire air course is traveled.
    (3) In each longwall or shortwall travelway in its entirety, so 
that the entire travelway is traveled.
    (4) At each seal along return and bleeder air courses and at each 
seal along intake air courses not examined under Sec. 75.360(b)(5).
    (5) In each escapeway so that the entire escapeway is traveled.
    (6) On each working section not examined under Sec. 75.360(b)(3) 
during the previous 7 days.
    (7) At each water pump not examined during a preshift examination 
conducted during the previous 7 days.
    (c) Measurements and tests. At least every 7 days, a certified 
person shall--
    (1) Determine the volume of air entering the main intakes and in 
each intake split;
    (2) Determine the volume of air and test for methane in the last 
open crosscut in any pair or set of developing entries or rooms, in the 
return of each split of air immediately before it enters the main 
returns, and where the air leaves the main returns; and
    (3) Test for methane in the return entry nearest each set of seals 
immediately after the air passes the seals.
    (d) Hazardous conditions shall be corrected immediately. If the 
condition creates an imminent danger, everyone except those persons 
referred to in Sec. 104(c) of the Act shall be withdrawn from the area 
affected to a safe area until the hazardous condition is corrected.
    (e) The weekly examination may be conducted at the same time as the 
preshift or on-shift examinations.
    (f) (1) The weekly examination is not required during any 7 day 
period in which no one enters any underground area of the mine.
    (2) Except for certified persons required to make examinations, no 
one shall enter any underground area of the mine if a weekly 
examination has not been completed within the previous 7 days.
    (g) Certification. The person making the weekly examinations shall 
certify by initials, date, and the time that the examination was made. 
Certifications and times shall appear at enough locations to show that 
the entire area has been examined.
    (h) Recordkeeping. At the completion of any shift during which a 
portion of a weekly examination is conducted, a record of the results 
of each weekly examination, including a record of hazardous conditions 
found during each examination and their locations, the corrective 
action taken, and the results and location of air and methane 
measurements, shall be made. The results of methane tests shall be 
recorded as the percentage of methane measured by the examiner. The 
record shall be made by the person making the examination or a person 
designated by the operator. If made by a person other than the 
examiner, the examiner shall verify the record by the initials and date 
by or at the end of the shift for which the examination was made. The 
record shall be countersigned by the mine foreman or equivalent mine 
official by the end of the mine foreman's or equivalent mine official's 
next regularly scheduled working shift. The records required by this 
section shall be made in a secure book that is not susceptible to 
alteration or electronically in a computer system so as to be secure 
and not susceptible to alteration.
    (i) Retention period. Records shall be retained at a surface 
location at the mine for at least 1 year and shall be made available 
for inspection by authorized 

[[Page 9841]]
representatives of the Secretary and the representative of miners.


Sec. 75.370  Mine ventilation plan; submission and approval.

    (a) (1) The operator shall develop and follow a ventilation plan 
approved by the district manager. The plan shall be designed to control 
methane and respirable dust and shall be suitable to the conditions and 
mining system at the mine. The ventilation plan shall consist of two 
parts, the plan content as prescribed in Sec. 75.371 and the 
ventilation map with information as prescribed in Sec. 75.372. Only 
that portion of the map which contains information required under 
Sec. 75.371 will be subject to approval by the district manager.
    (2) The proposed ventilation plan and any revision to the plan 
shall be submitted in writing to the district manager. When revisions 
to a ventilation plan are proposed, only the revised pages, maps, or 
sketches of the plan need to be submitted. When required in writing by 
the district manager, the operator shall submit a fully revised plan by 
consolidating the plan and all revisions in an orderly manner and by 
deleting all outdated material.
    (3) (i) The mine operator shall notify the representative of miners 
at least 5 days prior to submission of a mine ventilation plan and any 
revision to a mine ventilation plan. If requested, the mine operator 
shall provide a copy to the representative of miners at the time of 
notification. In the event of a situation requiring immediate action on 
a plan revision, notification of the revision shall be given, and if 
requested, a copy of the revision shall be provided, to the 
representative of miners by the operator at the time of submittal;
    (ii) A copy of the proposed ventilation plan, and a copy of any 
proposed revision, submitted for approval shall be made available for 
inspection by the representative of miners; and
    (iii) A copy of the proposed ventilation plan, and a copy of any 
proposed revision, submitted for approval shall be posted on the mine 
bulletin board at the time of submittal. The proposed plan or proposed 
revision shall remain posted until it is approved, withdrawn or denied.
    (b) Following receipt of the proposed plan or proposed revision, 
the representative of miners may submit timely comments to the district 
manager, in writing, for consideration during the review process. A 
copy of these comments shall also be provided to the operator by the 
district manager upon request.
    (c) (1) The district manager will notify the operator in writing of 
the approval or denial of approval of a proposed ventilation plan or 
proposed revision. A copy of this notification will be sent to the 
representative of miners by the district manager.
    (2) If the district manager denies approval of a proposed plan or 
revision, the deficiencies of the plan or revision shall be specified 
in writing and the operator will be provided an opportunity to discuss 
the deficiencies with the district manager.
    (d) No proposed ventilation plan shall be implemented before it is 
approved by the district manager. Any intentional change to the 
ventilation system that alters the main air current or any split of the 
main air current in a manner that could materially affect the safety 
and health of the miners, or any change to the information required in 
Sec. 75.371 shall be submitted to and approved by the district manager 
before implementation.
    (e) Before implementing an approved ventilation plan or a revision 
to a ventilation plan, persons affected by the revision shall be 
instructed by the operator in its provisions.
    (f) The approved ventilation plan and any revisions shall be--
    (1) Provided upon request to the representative of miners by the 
operator following notification of approval;
    (2) Made available for inspection by the representative of miners; 
and
    (3) Posted on the mine bulletin board within 1 working day 
following notification of approval. The approved plan and revisions 
shall remain posted on the bulletin board for the period that they are 
in effect.
    (g) The ventilation plan for each mine shall be reviewed every 6 
months by an authorized representative of the Secretary to assure that 
it is suitable to current conditions in the mine.


Sec. 75.371  Mine ventilation plan; contents.

    The mine ventilation plan shall contain the information described 
below and any additional provisions required by the district manager:
    (a) The mine name, company name, mine identification number, and 
the name of the individual submitting the plan information.
    (b) Planned main mine fan stoppages, other than those scheduled for 
testing, maintenance or adjustment, including procedures to be followed 
during these stoppages and subsequent restarts (see Sec. 75.311(a)) and 
the type of device to be used for monitoring main mine fan pressure, if 
other than a pressure recording device (see 75.310(a)(4)).
    (c) Methods of protecting main mine fans and associated components 
from the forces of an underground explosion if a 15-foot offset from 
the nearest side of the mine opening is not provided (see 
Sec. 75.310(a)(6)); and the methods of protecting main mine fans and 
intake air openings if combustible material will be within 100 feet of 
the area surrounding the fan or these openings (see Sec. 75.311(f)).
    (d) Persons that will be permitted to enter the mine, the work 
these persons will do while in the mine, and electric power circuits 
that will be energized when a back-up fan system is used that does not 
provide the ventilating quantity provided by the main mine fan (see 
Sec. 75.311(c)).
    (e) The locations and operating conditions of booster fans 
installed in anthracite mines (see Sec. 75.302).
    (f) Section and face ventilation systems used, including drawings 
illustrating how each system is used, and a description of each 
different dust suppression system used on equipment on working 
sections.
    (g) Locations where the air quantities must be greater than 3,000 
cubic feet per minute (see Sec. 75.325(a)(1)).
    (h) In anthracite mines, locations where the air quantities must be 
greater than 1,500 cubic feet per minute (see Sec. 75.325(e)(1)).
    (i) Working places and working faces other than those where coal is 
being cut, mined, drilled for blasting or loaded, where a minimum air 
quantity will be maintained, and the air quantity at those locations 
(see Sec. 75.325(a)(1)).
    (j) The operating volume of machine mounted dust collectors or 
diffuser fans, if used (see Sec. 75.325(a)(3)).
    (k) The minimum mean entry air velocity in exhausting face 
ventilation systems where coal is being cut, mined, drilled for 
blasting, or loaded, if the velocity will be less than 60 feet per 
minute. Other working places where coal is not being cut, mined, 
drilled for blasting or loaded, where at least 60 feet per minute or 
some other minimum mean entry air velocity will be maintained (see 
Sec. 75.326).
    (l) The maximum distance if greater than 10 feet from each working 
face at which face ventilation control devices will be installed (see 
Sec. 75.330(b)(2)). The working places other than those where coal is 
being cut, mined, drilled for blasting or loaded, where face 
ventilation control devices will be used (see Sec. 75.330(b)(1)(ii).
    (m) The volume of air required in the last open crosscut or the 
quantity of air reaching the pillar line if greater than 9,000 cubic 
feet per minute (see Sec. 75.325(b)). 

[[Page 9842]]

    (n) In anthracite mines, the volume of air required in the last 
open crosscut or the quantity of air reaching the pillar line if 
greater than 5,000 cubic feet per minute (see Sec. 75.325(e)(2)).
    (o) Locations where separations of intake and return air courses 
will be built and maintained to other than the third connecting 
crosscut outby each working face (see Sec. 75.333(b)(1)).
    (p) The volume of air required at the intake to the longwall 
sections, if different than 30,000 cubic feet per minute (see 
Sec. 75.325(c)).
    (q) The velocities of air on a longwall or shortwall face, and the 
locations where the velocities must be measured (see 
Sec. 75.325(c)(2)).
    (r) The minimum quantity of air that will be provided during the 
installation and removal of mechanized mining equipment, the location 
where this quantity will be provided, and the ventilation controls that 
will be used. (see Sec. 75.325(d)).
    (s) The locations and frequency of the methane tests if required 
more often by Sec. 75.362(d)(1)(iii) (see Sec. 75.362 (d)(1)(iii).
    (t) The locations where samples for ``designated areas'' will be 
collected, including the specific location of each sampling device, and 
the respirable dust control measures used at the dust generating 
sources for these locations (see Sec. 70.208 of this chapter).
    (u) The methane and dust control systems at underground dumps, 
crushers, transfer points, and haulageways.
    (v) Areas in trolley haulage entries where the air velocity will be 
greater than 250 feet per minute and the velocity in these areas (see 
Sec. 75.327(b)).
    (w) Locations where entries will be advanced less than 20 feet from 
the inby rib without a crosscut being provided where a line brattice 
will be required. (see Sec. 75.333(g)).
    (x) A description of the bleeder system to be used, including its 
design (see Sec. 75.334).
    (y) The means for determining the effectiveness of bleeder systems 
(see Sec. 75.334(c)(2)).
    (z) The locations where measurements of methane and oxygen 
concentrations and air quantities and tests to determine whether the 
air is moving in the proper direction will be made to evaluate the 
ventilation of nonpillared worked-out areas (see Sec. 75.364 (a)(1)) 
and the effectiveness of bleeder systems (see Sec. 75.364 (a)(2)(iii). 
Alternative methods of evaluation of the effectiveness of bleeder 
systems (Sec. 75.364 (a)(2)(iv)).
    (aa) The means for adequately maintaining bleeder entries free of 
obstructions such as roof falls and standing water (see 
Sec. 75.334(c)(3)).
    (bb) The location of ventilation devices such as regulators, 
stoppings and bleeder connectors used to control air movement through 
worked-out areas (see Sec. 75.334(c)(4)). The location and sequence of 
construction of proposed seals for each worked-out area. (see 
Sec. 75.334(e)).
    (cc) In mines with a demonstrated history of spontaneous 
combustion: a description of the measures that will be used to detect 
methane, carbon monoxide, and oxygen concentration during and after 
pillar recovery and in worked-out areas where no pillars have been 
recovered (see Sec. 75.334(f)(1); and, the actions which will be taken 
to protect miners from the hazards associated with spontaneous 
combustion (see Sec. 75.334(f)(2). If a bleeder system will not be 
used, the methods that will be used to control spontaneous combustion, 
accumulations of methane-air mixtures, and other gases, dusts, and 
fumes in the worked-out area (see Sec. 75.334(f)(3)).
    (dd) The location of all horizontal degasification holes that are 
longer than 1,000 feet and the location of all vertical degasification 
holes.
    (ee) If methane drainage systems are used, a detailed sketch of 
each system, including a description of safety precautions used with 
the systems.
    (ff) A description of the methods and materials to be used to seal 
worked-out areas if those methods or materials will be different from 
those specified by Sec. 75.335(a)(1).
    (gg) The alternative location for the additional sensing device if 
the device will not be installed on the longwall shearing machine (see 
Sec. 75.342(a)(2)).
    (hh) The ambient level in parts per million of carbon monoxide, and 
the method for determining the ambient level, in all areas where carbon 
monoxide sensors are installed.
    (ii) The distance that separation between the primary escapeway and 
the belt or track haulage entries will be maintained if other than to 
the first connecting crosscut outby the section loading point (see 
Sec. 75.380(g)).
    (jj) In anthracite mines, the dimensions of escapeways where the 
pitch of the coal seam does not permit escapeways to be maintained 4 
feet by 5 feet and the locations where these dimensions must be 
maintained (see Sec. 75.381(c)(4)).


Sec. 75.372  Mine ventilation map.

    (a)(1) At intervals not exceeding 12 months, the operator shall 
submit to the district manager 3 copies of an up-to-date map of the 
mine drawn to a scale of not less than 100 nor more than 500 feet to 
the inch. A registered engineer or a registered surveyor shall certify 
that the map is accurate.
    (2) In addition to the informational requirements of this section 
the map may also be used to depict and explain plan contents that are 
required in Sec. 75.371. Information shown on the map to satisfy the 
requirements of Sec. 75.371 shall be subject to approval by the 
district manager.
    (b) The map shall contain the following information:
    (1) The mine name, company name, mine identification number, a 
legend identifying the scale of the map and symbols used, and the name 
of the individual responsible for the information on the map.
    (2) All areas of the mine, including sealed and unsealed worked-out 
areas.
    (3) All known mine workings that are located in the same coalbed 
within 1,000 feet of existing or projected workings. These workings may 
be shown on a mine map with a scale other than that required by 
paragraph (a) of this section, if the scale does not exceed 2,000 feet 
to the inch and is specified on the map.
    (4) The locations of all known mine workings underlying and 
overlying the mine property and the distance between the mine workings.
    (5) The locations of all known oil and gas wells and all known 
drill holes that penetrate the coalbed being mined.
    (6) The locations of all main mine fans, installed backup fans and 
motors, and each fan's specifications, including size, type, model 
number, manufacturer, operating pressure, motor horsepower, and 
revolutions per minute.
    (7) The locations of all surface mine openings and the direction 
and quantity of air at each opening.
    (8) The elevation at the top and bottom of each shaft and slope, 
and shaft and slope dimensions, including depth and length.
    (9) The direction of air flow in all underground areas of the mine.
    (10) The locations of all active working sections and the four-
digit identification number for each mechanized mining unit (MMU).
    (11) The location of all escapeways.
    (12) The locations of all ventilation controls, including permanent 
stoppings, overcasts, undercasts, regulators, seals, airlock doors, 
haulageway doors and other doors, except temporary ventilation controls 
on working sections.
    (13) The direction and quantity of air--
    (i) Entering and leaving each split;
    (ii) In the last open crosscut of each set of entries and rooms; 
and 

[[Page 9843]]

    (iii) At the intake end of each pillar line, including any longwall 
or shortwall.
    (14) Projections for at least 12 months of anticipated mine 
development, proposed ventilation controls, proposed bleeder systems, 
and the anticipated location of intake and return air courses, belt 
entries, and escapeways.
    (15) The locations of existing methane drainage systems.
    (16) The locations of all atmospheric monitoring system sensors.
    (17) Contour lines that pass through whole number elevations of the 
coalbed being mined. These lines shall be spaced at 10-foot elevation 
levels unless a wider spacing is permitted by the district manager.
    (18) The location of proposed seals for each worked-out area.
    (19) The entry height, velocity and direction of the air current at 
or near the midpoint of each belt flight where the height and width of 
the entry are representative of the belt haulage entry.
    (20) The location and designation of air courses that have been 
redesignated from intake to return for the purpose of ventilation of 
structures, areas or installations that are required by this subpart D 
to be ventilated to return air courses, and for ventilation of seals.
    (c) The mine map required by Sec. 75.1200 may be used to satisfy 
the requirements for the ventilation map, provided that all the 
information required by this section is contained on the map.


Sec. 75.373  Reopening mines.

    After a mine is abandoned or declared inactive, and before it is 
reopened, mining operations shall not begin until MSHA has been 
notified and has completed an inspection.


Sec. 75.380  Escapeways; bituminous and lignite mines.

    (a) Except in situations addressed in Sec. 75.381, Sec. 75.385 and 
Sec. 75.386, at least two separate and distinct travelable passageways 
shall be designated as escapeways and shall meet the requirements of 
this section.
    (b) (1) Escapeways shall be provided from each working section, and 
each area where mechanized mining equipment is being installed or 
removed, continuous to the surface escape drift opening or continuous 
to the escape shaft or slope facilities to the surface.
    (2) During equipment installation, these escapeways shall begin at 
the projected location for the section loading point. During equipment 
removal, they shall begin at the location of the last loading point.
    (c) The two separate and distinct escapeways required by this 
section shall not end at a common shaft, slope, or drift opening, 
except that multiple compartment shafts or slopes separated by walls 
constructed of noncombustible material may be used as separate and 
distinct passageways.
    (d) Each escapeway shall be--
    (1) Maintained in a safe condition to always assure passage of 
anyone, including disabled persons;
    (2) Clearly marked to show the route and direction of travel to the 
surface;
    (3) Maintained to at least a height of 5 feet from the mine floor 
to the mine roof, excluding the thickness of any roof support, except 
that the escapeways shall be maintained to at least the height of the 
coalbed, excluding the thickness of any roof support, where the coalbed 
is less than 5 feet. In areas of mines where escapeways pass through 
doors, the height may be less than 5 feet, provided that sufficient 
height is maintained to enable miners, including disabled persons, to 
escape quickly in an emergency. In areas of mines developed before 
November 16, 1992, where escapeways pass over or under overcasts or 
undercasts, the height may be less than 5 feet provided that sufficient 
height is maintained to enable miners, including disabled persons, to 
escape quickly in an emergency. When there is a need to determine 
whether sufficient height is provided, MSHA may require a stretcher 
test where 4 persons carry a miner through the area in question on a 
stretcher;
    (4) Maintained at least 6 feet wide except--
    (i) Where necessary supplemental roof support is installed, the 
escapeway shall not be less than 4 feet wide; or
    (ii) Where the route of travel passes through doors or other 
permanent ventilation controls, the escapeway shall be at least 4 feet 
wide to enable miners to escape quickly in an emergency, or
    (iii) Where the alternate escapeway passes through doors or other 
permanent ventilation controls or where supplemental roof support is 
required and sufficient width is maintained to enable miners, including 
disabled persons, to escape quickly in an emergency. When there is a 
need to determine whether sufficient width is provided, MSHA may 
require a stretcher test where 4 persons carry a miner through the area 
in question on a stretcher, or
    (iv) Where mobile equipment near working sections, and other 
equipment essential to the ongoing operation of longwall sections, is 
necessary during normal mining operations, such as material cars 
containing rock dust or roof control supplies, or is to be used for the 
evacuation of miners off the section in the event of an emergency. In 
any instance, escapeways shall be of sufficient width to enable miners, 
including disabled persons, to escape quickly in an emergency. When 
there is a need to determine whether sufficient width is provided, MSHA 
may require a stretcher test where 4 persons carry a miner through the 
area in question on a stretcher;
    (5) Located to follow the most direct, safe and practical route to 
the nearest mine opening suitable for the safe evacuation of miners; 
and
    (6) Provided with ladders, stairways, ramps, or similar facilities 
where the escapeways cross over obstructions.
    (e) Surface openings shall be adequately protected to prevent 
surface fires, fumes, smoke, and flood water from entering the mine.
    (f) Primary escapeway. (1) One escapeway that is ventilated with 
intake air shall be designated as the primary escapeway.
    (2) Paragraphs (f)(3) through (f)(7) of this section apply as 
follows:
    (i) To all areas of a primary escapeway developed on or after 
November 16, 1992;
    (ii) Effective as of March 11, 1997, to all areas of a primary 
escapeway developed between March 30, 1970 and November 16, 1992; and
    (iii) Effective as of March 11, 1997, to all areas of the primary 
escapeway developed prior to March 30, 1970 where separation of the 
belt and trolley haulage entries from the primary escapeway existed 
prior to November 16, 1992.
    (3) The following equipment is not permitted in the primary 
escapeway:
    (i) Unattended operating diesel equipment without an automatic fire 
suppression system.
    (ii) Mobile equipment hauling coal except for hauling coal 
incidental to cleanup or maintenance of the primary escapeway.
    (iii) Compressors, except--
    (A) Compressors necessary to maintain the escapeway in safe, 
travelable condition;
    (B) Compressors that are components of equipment such as 
locomotives and rock dusting machines; and
    (C) Compressors of less than five horsepower.
    (iv) Underground transformer stations, battery charging stations, 
substations, and rectifiers except--
    (A) Where necessary to maintain the escapeway in safe, travelable 
condition; and
    (B) Battery charging stations and rectifiers and power centers with 


[[Page 9844]]
transformers that are either dry-type or contain nonflammable liquid, 
provided they are located on or near a working section and are moved as 
the section advances or retreats.
    (v) Water pumps, except--
    (A) Water pumps necessary to maintain the escapeway in safe, 
travelable condition;
    (B) Submersible pumps;
    (C) Permissible pumps and associated permissible switchgear;
    (D) Pumps located on or near a working section that are moved as 
the section advances or retreats;
    (E) Pumps installed in anthracite mines; and
    (F) Small portable pumps.
    (4) Mobile equipment operated in the primary escapeway, except for 
continuous miners and as provided in paragraphs (f)(5), (f)(6), and 
(f)(7) of this section, shall be equipped with a fire suppression 
system installed according to Secs. 75.1107-3 through 75.1107-16 that 
is--
    (i) Manually operated and attended continuously by a person trained 
in the systems function and use, or
    (ii) A multipurpose dry chemical type capable of both automatic and 
manual activation.
    (5) Personnel carriers and small mobile equipment designed and used 
only for carrying people and small hand tools may be operated in 
primary escapeways if--
    (i) The equipment is provided with a multipurpose dry chemical type 
fire suppression system capable of both automatic and manual 
activation, and the suppression system is suitable for the intended 
application and is listed or approved by a nationally recognized 
independent testing laboratory, or,
    (ii) Battery powered and provided with two 10 pound multipurpose 
dry chemical portable fire extinguishers.
    (6) Notwithstanding the requirements of paragraph (f)(3)(i), mobile 
equipment not provided with a fire suppression system may operate in 
the primary escapeway if no one is inby except those persons directly 
engaged in using or moving the equipment.
    (7) Notwithstanding the requirements of paragraph (f)(3)(i), mobile 
equipment designated and used only as emergency vehicles or ambulances, 
may be operated in the primary escapeway without fire suppression 
systems.
    (g) Except where separation of belt and trolley haulage entries 
from designated escapeways did not exist before November 15, 1992, the 
primary escapeway shall be separated from belt and trolley haulage 
entries for its entire length, to and including the first connecting 
crosscut outby each loading point except when a greater or lesser 
distance for this separation is specified and approved in the 
ventilation plan and does not pose a hazard to miners.
    (h) Alternate escapeway. One escapeway shall be designated as the 
alternate escapeway. The alternate escapeway shall be separated from 
the primary escapeway for its entire length, except that the alternate 
and primary escapeways may be ventilated from a common intake air shaft 
or slope opening.
    (i) Mechanical escape facilities shall be provided and maintained 
for--
    (1) Each shaft that is part of a designated escapeway and is 
greater than 50 feet in depth; and
    (2) Each slope from the coal seam to the surface that is part of a 
designated escapeway and is inclined more than 9 degrees from the 
horizontal.
    (j) Within 30 minutes after mine personnel on the surface have been 
notified of an emergency requiring evacuation, mechanical escape 
facilities provided under paragraph (i) of this section shall be 
operational at the bottom of shaft and slope openings that are part of 
escapeways.
    (k) Except where automatically activated hoisting equipment is 
used, the bottom of each shaft or slope opening that is part of a 
designated escapeway shall be equipped with a means of signaling a 
surface location where a person is always on duty when anyone is 
underground. When the signal is activated or the evacuation of persons 
underground is necessary, the person shall assure that mechanical 
escape facilities are operational as required by paragraph (j) of this 
section.
    (l) (1) Stairways or mechanical escape facilities shall be 
installed in shafts that are part of the designated escapeways and that 
are 50 feet or less in depth, except ladders may be used in shafts that 
are part of the designated escapeways and that are 5 feet or less in 
depth.
    (2) Stairways shall be constructed of concrete or metal, set on an 
angle not to exceed 45 degrees from the horizontal, and equipped on the 
open side with handrails. In addition, landing platforms that are at 
least 2 feet by 4 feet shall be installed at intervals not to exceed 20 
vertical feet on the stairways and equipped on the open side with 
handrails.
    (3) Ladders shall be constructed of metal, anchored securely, and 
set on an angle not to exceed 60 degrees from the horizontal.
    (m) A travelway designed to prevent slippage shall be provided in 
slope and drift openings that are part of designated escapeways, unless 
mechanical escape facilities are installed.


Sec. 75.381  Escapeways; anthracite mines.

    (a) Except as provided in Secs. 75.385 and 75.386, at least two 
separate and distinct travelable passageways shall be designated as 
escapeways and shall meet the requirements of this section.
    (b) Escapeways shall be provided from each working section 
continuous to the surface.
    (c) Each escapeway shall be--
    (1) Maintained in a safe condition to always assure passage of 
anyone, including disabled persons;
    (2) Clearly marked to show the route of travel to the surface;
    (3) Provided with ladders, stairways, ramps, or similar facilities 
where the escapeways cross over obstructions; and
    (4) Maintained at least 4 feet wide by 5 feet high. If the pitch or 
thickness of the coal seam does not permit these dimensions to be 
maintained other dimensions may be approved in the ventilation plan.
    (d) Surface openings shall be adequately protected to prevent 
surface fires, fumes, smoke, and flood water from entering the mine.
    (e) Primary escapeway. One escapeway that shall be ventilated with 
intake air shall be designated as the primary escapeway.
    (f) Alternate escapeway. One escapeway that shall be designated as 
the alternate escapeway shall be separated from the primary escapeway 
for its entire length.
    (g) Mechanical escape facilities shall be provided--
    (1) For each shaft or slope opening that is part of a primary 
escapeway; and
    (2) For slopes that are part of escapeways, unless ladders are 
installed.
    (h) Within 30 minutes after mine personnel on the surface have been 
notified of an emergency requiring evacuation, mechanical escape 
facilities shall be operational at the bottom of each shaft and slope 
opening that is part of an escapeway.
    (i) Except where automatically activated hoisting equipment is 
used, the bottom of each shaft or slope opening that is part of a 
primary escapeway shall be equipped with a means of signaling a surface 
location where a person is always on duty when anyone is underground. 
When the signal is activated or the evacuation of personnel is 
necessary, the person on duty shall assure that mechanical escape 
facilities are operational as required by paragraph (h) of this 
section. 

[[Page 9845]]



Sec. 75.382  Mechanical escape facilities.

    (a) Mechanical escape facilities shall be provided with overspeed, 
overwind, and automatic stop controls.
    (b) Every mechanical escape facility with a platform, cage, or 
other device shall be equipped with brakes that can stop the fully 
loaded platform, cage, or other device.
    (c) Mechanical escape facilities, including automatic elevators, 
shall be examined weekly. The weekly examination of this equipment may 
be conducted at the same time as a daily examination required by 
Sec. 75.1400-3.
    (1) The weekly examination shall include an examination of the 
headgear, connections, links and chains, overspeed and overwind 
controls, automatic stop controls, and other facilities.
    (2) At least once each week, the hoist shall be run through one 
complete cycle of operation to determine that it is operating properly.
    (d) A person trained to operate the mechanical escape facility 
always shall be available while anyone is underground to provide the 
mechanical escape facilities, if required, to the bottom of each shaft 
and slope opening that is part of an escapeway within 30 minutes after 
personnel on the surface have been notified of an emergency requiring 
evacuation. However, no operator is required for automatically operated 
cages, platforms, or elevators.
    (e) Mechanical escape facilities shall have rated capacities 
consistent with the loads handled.
    (f) Manually-operated mechanical escape facilities shall be 
equipped with indicators that accurately and reliably show the position 
of the facility.
    (g) Certification. The person making the examination as required by 
paragraph (c) of this section shall certify by initials, date, and the 
time that the examination was made. Certifications shall be made at or 
near the facility examined.


Sec. 75.383  Escapeway maps and drills.

    (a) A map shall be posted or readily accessible to all miners in 
each working section, and in each area where mechanized mining 
equipment is being installed or removed. The map shall show the 
designated escapeways from the working section to the location where 
miners must travel to satisfy the escapeway drill specified in 
paragraph (b)(1) of this section. A map showing the main escapeways 
shall be posted at a surface location of the mine where miners 
congregate, such as at the mine bulletin board, bathhouse, or waiting 
room. All maps shall be kept up to date, and any changes in route of 
travel, locations of doors, or directions of airflow shall be shown on 
the maps by the end of the shift on which the changes are made, and 
affected miners shall be informed of the changes before entering the 
underground areas of the mine. Miners underground on a shift when any 
such change is made shall be immediately notified of the change.
    (b) (1) At least once every 90 days, each miner, including miners 
with working stations located between working sections and main 
escapeways, shall participate in a practice escapeway drill. During 
this drill, each miner shall travel the primary or alternate escapeway 
from the miner's working section or area where mechanized mining 
equipment is being installed or removed, to the area where the split of 
air ventilating the working section intersects a main air course, or 
2,000 feet outby the section loading point, whichever distance is 
greater. Other miners shall participate in the escapeway drill by 
traveling in the primary or alternate escapeway for a distance of 2,000 
feet from their working station toward the nearest escape facility or 
drift opening. An escapeway drill shall not be conducted in the same 
escapeway as the immediately preceding drill.
    (2) At least once every 6 weeks and for each shift, at least two 
miners on each coal producing working section who work on that section, 
accompanied by the section supervisor, shall participate in a practice 
escape drill and shall travel the primary or alternate escapeway from 
the location specified in paragraph (b)(1) of this section, to the 
surface, to mechanical escape facilities, or to an underground entrance 
to a shaft or slope to the surface. Systematic rotation of section 
personnel shall be used so that all miners participate in this drill. 
An escapeway drill shall not be conducted in the same escapeway as the 
immediately preceding drill.
    (3) At least once every 6 weeks, at least two miners on each 
maintenance shift and a supervisor, shall participate in a practice 
escape drill and shall travel the primary or alternate escapeway from 
the location specified in paragraph (b)(1) of this section, to the 
surface, to mechanical escape facilities, or to an underground entrance 
to a shaft or slope to the surface. Systematic rotation of maintenance 
personnel and working sections shall be used so that all miners 
participate in this drill and the escapeways from all sections are 
traveled. An escapeway drill shall not be conducted in the same 
escapeway as the immediately preceding drill.
    (4) Before or during practice escapeway drills, miners shall be 
informed of the locations of fire doors, check curtains, changes in the 
routes of travel, and plans for diverting smoke from escapeways.
    (c) The practice escapeway drills may be used to satisfy the 
evacuation specifications of the fire drills required by Sec. 75.1101-
23.


Sec. 75.384  Longwall and shortwall travelways.

    (a) If longwall or shortwall mining systems are used and the two 
designated escapeways required by Sec. 75.380 are located on the 
headgate side of the longwall or shortwall, a travelway shall be 
provided on the tailgate side of that longwall or shortwall. The 
travelway shall be located to follow the most direct and safe practical 
route to a designated escapeway.
    (b) The route of travel shall be clearly marked.
    (c) When a roof fall or other blockage occurs that prevents travel 
in the travelway--
    (1) Work shall cease on the longwall or shortwall face;
    (2) Miners shall be withdrawn from face areas to a safe area outby 
the section loading point; and
    (3) MSHA shall be notified.
    (d) Work may resume on the longwall or shortwall face after the 
procedures set out in Secs. 75.215 and 75.222 are implemented.


Sec. 75.385  Opening new mines.

    When new mines are opened, no more than 20 miners at a time shall 
be allowed in any mine until a connection has been made between the 
mine openings, and these connections shall be made as soon as possible.


Sec. 75.386  Final mining of pillars.

    When only one mine opening is available due to final mining of 
pillars, no more than 20 miners at a time shall be allowed in the mine, 
and the distance between the mine opening and working face shall not 
exceed 500 feet.


Sec. 75.388  Boreholes in advance of mining.

    (a) Boreholes shall be drilled in each advancing working place when 
the working place approaches--
    (1) To within 50 feet of any area located in the mine as shown by 
surveys that are certified by a registered engineer or registered 
surveyor unless the area has been preshift examined;
    (2) To within 200 feet of any area located in the mine not shown by 
surveys that are certified by a registered engineer or registered 
surveyor unless the area has been preshift examined; or
    (3) To within 200 feet of any mine workings of an adjacent mine 
located in 

[[Page 9846]]
the same coalbed unless the mine workings have been preshift examined.
    (b) Boreholes shall be drilled as follows:
    (1) Into the working face, parallel to the rib, and within 3 feet 
of each rib.
    (2) Into the working face, parallel to the rib, and at intervals 
across the face not to exceed 8 feet.
    (3) At least 20 feet in depth in advance of the working face, and 
always maintained to a distance of 10 feet in advance of the working 
face.
    (c) Boreholes shall be drilled in both ribs of advancing working 
places described in paragraph (a) of this section unless an alternative 
drilling plan is approved by the District Manager in accordance with 
paragraph (g) of this section. These boreholes shall be drilled--
    (1) At an angle of 45 degrees to the direction of advance;
    (2) At least 20 feet in depth; and
    (3) At intervals not to exceed 8 feet.
    (d) When a borehole penetrates an area that cannot be examined, and 
before mining continues, a certified person shall, if possible, 
determine--
    (1) The direction of airflow in the borehole;
    (2) The pressure differential between the penetrated area and the 
mine workings;
    (3) The concentrations of methane, oxygen, carbon monoxide, and 
carbon dioxide; and
    (4) Whether water is impounded within the penetrated area.
    (e) Unless action is taken to dewater or to ventilate penetrated 
areas, boreholes shall be plugged with wooden plugs or similar devices 
when--
    (1) Tests conducted at the boreholes show that the atmosphere in 
the penetrated area contains more than 1.0 percent methane, less than 
19.5 percent oxygen, or harmful concentrations of carbon monoxide, 
carbon dioxide or other explosive, harmful or noxious gases;
    (2) Tests for methane, oxygen, carbon monoxide, and carbon dioxide 
cannot be made because air from mine workings is flowing into the 
penetrated area; or
    (3) Water is discharging through the boreholes from the penetrated 
area into the mine workings.
    (f) If mining is to be conducted within 50 feet above or below an 
inaccessible area of another mine, boreholes shall be drilled, as 
necessary, according to a plan approved by the district manager.
    (g) Alternative borehole patterns that provide the same protection 
to miners as the pattern established by paragraphs (b) and (c) of this 
section may be used under a plan approved by the district manager.


Sec. 75.389  Mining into inaccessible areas.

    (a) (1) The operator shall develop and follow a plan for mining 
into areas penetrated by boreholes drilled under Sec. 75.388.
    (2) Mining shall not resume into any area penetrated by boreholes 
until conditions in the penetrated area can be determined under 
Sec. 75.388 and the plan for mining-through into the area has been 
approved by the district manager.
    (3) A copy of the procedures to be followed shall be posted near 
the site of the mining-through operations and the operator shall 
explain these procedures to all miners involved in the operations.
    (b) The procedures specified in the plan shall include--
    (1) The method of ventilation, ventilation controls, and the air 
quantities and velocities in the affected working section and working 
place;
    (2) Dewatering procedures to be used if a penetrated area contains 
a water accumulation; and
    (3) The procedures and precautions to be followed during mining-
through operations.
    (c) Except for routine mining-through operations that are part of a 
retreat section ventilation system approved in accordance with 
Sec. 75.371(f) and (x), the following provisions shall apply:
    (1) Before and during mining-through operations, a certified person 
shall perform air quality tests at intervals and at locations necessary 
to protect the safety of the miners.
    (2) During mining-through operations, only persons involved in 
these operations shall be permitted in the mine; and
    (3) After mining-through, a certified person shall determine that 
the affected areas are safe before any persons enter the underground 
areas of the mine.

[FR Doc. 96-5453 Filed 3-6-96; 11:23 am]
BILLING CODE 4510-43-P