VOLUME V - COAL MINES
77.1103 Flammable Liquids; Storage
Reference is made to the standards of the National Fire Protection Association and the applicable portion in Code No. 30--Flammable and Combustible Liquids. The basic requirements for storing flammable liquids are:
- Buildings or rooms within buildings in which flammable and combustible liquids are stored shall be of noncombustible structure, including walls, floor, and ceiling; properly ventilated and, where possible, located away from stairways or exits. If heated, only electric heaters, hot water, or low-pressure steam shall be used.
- Drums and other containers stored in the open shall be located to reduce the spread of fire to other materials in storage or other property areas. The surrounding area shall be kept free of combustible materials, brush, etc.
77.1104 Accumulations of Combustible Materials
This Section, in essence, refers to good housekeeping. Excessive quantities of coal or coal dust shall not be permitted to accumulate, particularly where other highly flammable materials are present.
77.1106 Battery-Charging Stations; Ventilation
Battery-charging stations shall be adequately ventilated to prevent the accumulation of explosive gases, particularly hydrogen which can be released during the charging cycle.
77.1108 Fire fighting Equipment; Requirements; General
The intent of this general paragraph is to give the operator a choice in the type of extinguishing agent and, in some respects,the size or quantity of the unit. Questions can arise on the definition of the term "adequate supply," particularly for portable fire extinguishers as, for example, at a motor drive.Many of these questions can be answered by referring to the National Fire Protection Codes, particularly Code No. 10.
The entire fire control system shall be considered. For example,if the operator provides a sprinkler system at a hazardous location, then smaller hand-held units would be acceptable at a specific location within the sprinkler-protected area. Likewise,if a good water hydrant-hose system is offered, then small units could be acceptable at a specific location. An isolated plant ordinarily would require a higher degree of protection than a plant served by a local fire department.
77.1108-1 Type and Capacity of Fire fighting Equipment
The size and location of fire extinguishers required in paragraph (b) should follow recommendations given in the appropriate National Fire Protection Association Codes. The type of extinguishing agent shall conform with the size and class of potential fire hazard. Carbon tetrachloride fire extinguishers are not acceptable in accordance with the National Fire Protection Code. Carbon tetrachloride is toxic and is harmful if not handled properly.
77.1109 Quantity and Location of Fire fighting Equipment
When questions arise concerning paragraph (a), the standards presented in National Fire Protection Code No. 10 shall be used as a guide. Generally, a minimum of one extinguisher having a rating no less than 2A8B or 2A8BC where electrical installations are present shall be provided on each floor or level in the structure. At least one extinguisher shall be provided for each 3,000 square feet of floor space.
Where the floor space exceeds 3,000 square feet, and more than one extinguisher is required, they shall be no more than 75 feet apart. If the area protected contains permanent electrical installations, the maximum distance between extinguishers shall be no more than 50 feet.
The purpose of paragraph (b) is to insure that a water stream or dry powder extinguishing agent can be applied at any location in the building. The 125-pound extinguisher can be a single unit or made up of several smaller units, provided the total weight of powder meets the requirement.
A 125-pound dry chemical extinguishing unit shall be provided for each 5,000 square feet of floor area in a building of noncombustible construction, or 2,500 square feet area in abuilding of combustible construction.
A single 125-pound unit can provide protection for more than a single floor if the system is permanently installed with rigid piping. Thus, a portable 125-pound unit can serve only a single floor, but a permanently installed unit may serve one or more floors, provided the floor area does not exceed 2,500 or 5,000square feet, depending on the type of construction.
The following portable fire extinguisher ratings will be acceptable as meeting the requirements of paragraph (c)(1). All trucks up to and including those of 20-ton (load) capacity should be equipped with at least one extinguisher having a minimum rating of 5BC. Trucks larger than 20-ton capacity should be equipped with an extinguisher having at least a 10BC rating.Two 5BC extinguishers are acceptable.
Other mobile equipment, such as front-end loaders, bulldozers,portable welding units, and augers of comparable size (to the trucks) should be rated on an equivalent basis, except hydraulically-operated equipment containing flammable and combustible liquids, trucks transporting flammable and combustible liquids, and diesel-powered motor generator sets.Examples are as follows:
- A front-end loader or portable welding unit no larger in size (weight) than a 20-ton truck should require the same protection as a 20-ton truck or 5BC.
- A front-end loader, bulldozer, auger, etc., larger than a 20-ton truck should require the same protection as a truck larger than a 20-ton or 10BC.
Paragraph (c)(2) requires equipment larger in size than that equivalent to a 50-ton truck to be provided with additional fire protection commensurate with the hazard. A minimum of one extinguisher having the proper rating shall be provided on each of all multilevel equipment such as shovels and draglines.
The extinguisher required by paragraph (c)(3) should be rated no less than 5BC.
When implementing paragraph (d), judgment shall be used in the evaluation of the requirements for extinguishers at each permanent electrical installation. One portable extinguisher can serve several adjacent electric motors or transformers.Extinguishers provided and located according to paragraph (a)shall be acceptable as protection for electrical installations within that area, provided such extinguishers are no more than 50 feet from the electrical installation.
Substation - Two extinguishers having a total rating of 20BCshall be provided at permanent substations.
The requirement in paragraph (e) of two portable fire extinguishers at the stated combustible liquid storage depots clarified in NFPA Code No. 30 means that two portable units, each having a rating of not less than 10-B units, shall be provided.Questions will arise as to whether a single extinguisher having a rating of 20-B units can be used instead of two 10-B fire extinguishers. Decisions shall be made for individual circumstances. Two 10-B extinguishers are generally preferred,as a greater chance exists that at least one unit will not be downwind of the fire. Decisions shall be based on the size of liquid storage, location and surrounding conditions. Rock dust in the amount of at least 500 pounds, kept dry and maintained usable, will be acceptable as "equivalent" to two portable extinguishers at remote combustible liquid storage installations,provided a shovel or equivalent means is available for applying the rock dust.
Fire protection referred to in paragraph (f) means two extinguishers having a rating of not less than 5BC each.
Subpart N .... Explosives and Blasting
77.1300 Explosives and Blasting
Refer to Section 75.1300 for the policies related to joint MSHA and ATF activities.
77.1303 Explosives; Handling and Use
The following are guidelines for enforcing paragraph (g):
In the event the explosive haulage vehicle has to be moved within the blasting area, precautions shall be taken to avoid driving the vehicle over or dragging hoses over firing lines, detonator wires or explosive materials. The driver, in moving the vehicle,shall obtain the assistance of a second person to guide his/her movement.
During charging and firing, only the work activities associated with the explosives operation shall be permitted in the blasting area. Blasting operations shall be under the direct control of authorized persons. Boreholes shall be stemmed immediately after charging and shots, shall be fired as soon as practical after charging has been completed.
Holes to be blasted shall be charged as near to blasting time as practical, and such holes shall be blasted as soon as possible after charging has been completed. Where required to postpone the firing of the blast, the provisions of paragraph (g) shall be followed.
Paragraph (j) governs surface drilling and blasting when there is a danger that these operations can affect the active workings of an underground coal mine. In such instances, the appropriate orders should be issued to ensure that underground miners will be withdrawn from the endangered area before blasting is done.
To prevent damage to detonating cord, as addressed in paragraph(r), detonating cord down lines used in the charging of boreholes should be cut from the spool after the primed charge is in position.
Paragraph (qq) requires that, before entering the blast area,personnel shall make certain that it is completely free of visible reddish brown fumes, an indication of a highly toxic concentration of nitrogen dioxide gas.
MSHA recognizes that the use of ANFO, cast primers, and detonating cord, provides one of the safest means of blasting available. However, it should be emphasized that detonating cord and cast primers contain explosives and are designed to explode.Consequently, they should be used with respect and common sense afforded an explosive, and it must be kept in mind that every explosive can be detonated under certain critical conditions.
Subpart O .... Personnel Hoisting
77.1400 Personnel Hoists and Elevators
Safety systems utilizing safety belts attached to independently suspended safety lines by lanyards and rope grabs must be utilized when scaffolding hoists are used at surface facilities.
The following guidelines should be used when inspecting these devices:
- Lifelines must be attached to a structural member of the shaft or collar or surface facility and not to the hoist rope outrigger.
- Lifelines of at least first grade 5/8-inch nylon rope, 3/4-inch manila hemp rope, or equivalent, must be provided for each miner.
- Substantial safety belts securely attached to the independently suspended safety lines by lanyards and rope grabs must be used at all times when embarking, disembarking or working on the platform.
77.1501 Auger Mining; Inspections
"The drilling site," as referred to in paragraph (a), should include that area of the highwall under which augering operations will be conducted during the shift. "All loose material," as used, is to be construed to mean loose material that poses a hazard to miners.
The term, "shall be inspected frequently," as used in paragraph(b), shall be construed to mean that such inspections should be made at intervals not to exceed 30 minutes when augering operations are conducted during a heavy rainfall and as often as necessary to assure the safety of the worker after a heavy rainfall or during any period of intermittent freezing and thawing.
77.1504 Auger Equipment; Operation
The following example meets the requirements of paragraph (c):If the control cab on the augering machine is located directly above or to the side of the auger train, the auger machine operator shall not be considered as being in direct line with the borehole during augering operations.
To meet the requirements of paragraph (e), the face of highwalls at auger mining sites shall be provided with adequate illumination for a distance of 25 feet on both sides of each drilling site.
77.1505 Auger Holes; Blocking
In accordance with this Section, the blocking material should be piled at least 12 inches above the top of the auger hole to allow for settling. "Other suitable material" shall consist of material that will not fire readily.
Subpart Q .... Loading and Haulage
77.1605 Loading and Haulage Equipment; Installations
Cracks or discolorations in the cab windows that impair or distort the operator's vision or a crack that will damage the windshield wiper blade are examples of noncompliance of paragraph(a). Plexiglass may be used in lieu of safety glass in cab windows if the transparency is not impaired by scratches or discoloration.
Paragraph (k) is applicable to all elevated roadways on mine property, including roads used to transport coal, equipment,or personnel, and regardless of the size, location, or characterization of the roadways. Berms or guards are required on all exposed banks of elevated roadways. Thus, elevated roadways with two exposed banks are required to have berms or guards on both sides.
Berms or guardrails are required along the section of an elevated roadway crossing the crest of an impounding structure when the structure has been built to its final crest elevation and when the section of road over the impounding structure is completed.However, temporary berms or guardrails are not required along the section of an elevated roadway where it crosses the working surface of the impounding structure while the site is under active construction. Placement of such temporary berms or guardrails can be detrimental to the overall, long-term integrity of the structure, since the optimum moisture content and the required compaction parameters would be adversely affected.
On elevated roadways, leading to or constructed on the inclined surfaces of the impounding structure, berms or guardrails are required to be maintained as the structure increases in height.
If active construction on an impounding structure is suspended for any reason, and the roadway has not yet achieved the final elevation in accordance with the approved construction plan, then berms or guardrails are required if the site is an elevated roadway.
The requirements of paragraph (k) apply to that part of an elevated haulage road where one bank is, or both are, unprotected by a natural barrier which will prevent vehicles or equipment from running off and rolling down the unprotected bank(s).
"Elevated roadways," as used in this requirement, are roadways of sufficient height above the adjacent terrain to create a hazard in the event that mobile equipment should run off the roadway.
"Berm," as used in this Section, means a pile or mound of material at least axle high to the largest piece of equipment using such roadway and as wide at the base as the normal angle of repose provides. Where guardrails are used in lieu of berms,they shall be of substantial construction.
The width of the haulage road does not preclude the need for berms or guardrails.
77.1606 Loading and Haulage Equipment; Inspection and Maintenance
Mobile loading and haulage equipment shall be inspected by a competent person before such equipment is placed in operation at the beginning of each shift. Any defects found affecting safety during the required inspection shall be recorded and reported to the mine operator.
Subpart R .... Miscellaneous
77.1702 Arrangements for Emergency Medical Assistance and Transportation for Injured Persons; Reporting Requirements; Posting Requirements
Paragraphs (a) and (b) of this Section are not to be interpreted to mean that a physician or an ambulance must be present at the mine at all times. These paragraphs do mean, however, that the required services must be arranged for and be readily available.
Paragraphs (c) and (d) of this Section have been dis approved by the Office of Management and Budget (OMB) pursuant to authority under Executive Order 12174 (44 FR 69609) and the Paperwork Reduction Act of 1980. Beginning January 1, 1982, no enforcement action shall be taken relative to the reporting requirements of these two paragraphs.
Discontinuance of these information reporting requirements does not alter the requirements of paragraphs (a), (b), and (e) of this Section. Operators of surface coal mines still must have arrangements established with a licensed physician, medical service, medical clinic or hospital to provide 24-hour emergency medical assistance and must have arrangements with an ambulance service, or otherwise provide, for 24-hour emergency transportation for any person injured at the mine.
Likewise, operators must continue to post at appropriate places at the mine the names, titles, addresses, and telephone numbers of all persons or services available under the arrangements for medical assistance and emergency transportation. The posted information is required to be current and accurate. Where appropriate, inspectors shall make the necessary inquiries to determine the accuracy of the information posted.