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MSHA Federal Register Document
Rules and Regulations

Volume 61, Number 18, Page 2543

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.