VOLUME V - COAL MINES
75.1107-5 Electrical Components of Fire-Suppression
Devices; Permissibility Requirements
This Section and Section 75.1107-6 are general requirements for fire-suppression devices which permit the inspector to require proper devices for unusual conditions to insure that adequate fire controls will be achieved.
75.1107-6 Capacity of Fire-Suppression Devices; Location
and Direction of Nozzles
"Enclosed to minimize runoff and overshoot of the extinguishing agent," as used in paragraph (b) of this Section, does not prohibit necessary openings in cable-reel compartments to facilitate cleanliness of equipment, provided the discharge nozzle is not directed toward the openings.
Where practicable, and within the intent of these regulations, extinguishant nozzles shall not be located where accidental discharge of the system will endanger the operator of such equipment.
75.1107-7 Water Spray Devices; Capacity; Water Supply;
"Inundating" means covering the whole top of the machine either by direct or indirect water spray. "Internal injection" means directing the extinguishing agent into the compartment of the machine.
Past experience has shown that approximately 40 percent of the fires on machines have had a cable to ignite in the cable reel compartment. Some of these fires may have been caused by poor splices and the excessive heat liberated in the coiled cable. Whether fire control with water is achieved by inundating or internal injection, the indicated amount of water shall be directed into the cable reel compartment.
The requirements of paragraph (f) state that the quantity of liquid stored on the machine can be reduced appreciably if certain approved liquid chemicals are added to the water. Tests show that a potassium bicarbonate solution is three to four times more effective than plain water. However, potassium bicarbonate solution is corrosive to unalloyed steel. Other chemicals that are noncorrosive or contain inhibitors are as effective for fire control.
The use of liquid chemical is not mandatory, but the industry should be encouraged to use such additives in water.
75.1107-8 Fire-Suppression Devices; Extinguishant Supply
The purpose of the rising stem, or other visual indicator-type shutoff valve addressed in paragraph (a)(4), is to provide a visual means for assuring that the control valve is in the open position while the machine is operating.
"Reasonable time for changing hose," as used in paragraph (b) means without unnecessary delay.
75.1107-9 Dry Chemical Devices; Capacity; Minimum
In paragraphs (b) and (c) of this Section and subsequent regulations, the word "nominal" is used to express the approximate weight in pounds of all-purpose dry chemical.
75.1107-11 Extinguishing Agents; Requirements on Mining
Equipment Employed in Low Coal
This Section provides for lesser quantities of extinguishants on equipment with space limitations. However, there may be instances where the equipment is less than 32 inches high and may not have space limitations. In those instances the full complement of extinguishant shall be installed.
75.1107-12 Inerting of Mine Atmosphere Prohibited
The term "total flooding" does not mean total flooding with water, but control of the potentially hazardous area by inerting the whole atmosphere, i.e., carbon dioxide. This method of fire control is not recommended in mines because of the limited means of escape for miners who might be trapped in the enclosed space.
75.1107-13 Approval of Other Fire-Suppression Devices
Where installation of fire-suppression devices on permissible mine machinery requires alteration of components, a field change approval will be required.
75.1107-15 Fire-Suppression Devices; Hazards; Training of
This Section requires the operator to instruct the miners in safe operating procedures of fire-suppression devices on the equipment that the miners have been assigned to operate.
The inspector shall take appropriate action in each instance where the operator fails to instruct the equipment operator.
75.1107-16 Inspection of Fire-Suppression Devices
"Qualified," as used in paragraph (a) of this Section, does not mean formal training. A person qualified by reason of on-the-job experience and instruction may be designated by the mine operator to inspect the fire-suppression devices.
75.1108 Flame-Resistant Conveyor Belts
Conveyor belts which have been approved as flame-resistant by the Bureau of Mines, MESA, or MSHA are marked every 30 feet on alternate edges of the coal carrying side of the belt, with the following: Flame Resistant MESA, U.S.B.M., or MSHA No.
Subpart M .... Maps
75.1200 Mine Map
The original maps and tracings of a mine, those from which true copies are made, shall be kept in a fireproof repository to ensure the protection of such maps and tracings from damage or destruction by fire, water, or other such hazards.
Such repository shall be located on the surface of the mine in an area chosen by the operator. Such repository may be located on the surface at a central mine office or in the office of an individual, partnership, corporation, or other such firm contracting the engineering work for a mine, if the following conditions are met: A true copy of the mine map shall be maintained on the surface of the mine in a fireproof building or a fireproof container which meets the approval of the Coal Mine Safety and Health district manager of the district in which the mine is located, and such copy shall be certified by a registered engineer or registered surveyor in the state in which the mine is located.
75.1202 Temporary Notations, Revisions, and Supplements
The mine maps shall be kept up-to-date by temporary notations. However, such notations may be made on a true copy of the mine map. Such a true copy may be considered in compliance with the provision requiring that the mine map be kept up-to-date by temporary notations.
75.1203 Availability of Mine Map
The operator shall furnish to the Coal Mine Safety and Health district manager of the District in which the mine is located two copies of the mine map and any revision and supplement thereof on or before the first day of March of each year unless otherwise specified by the district manager. Such copies shall show all the required information, as posted on the mine map on or after the first day of January of each year.
75.1204 Mine Closure; Filing of Map With Secretary
If the mine is to be permanently abandoned, the operator shall notify the District Manager promptly after ventilation is discontinued and shall submit a complete map of the mine within 60 days of abandonment.
If the mine is to be temporarily closed, the operator shall notify the District Manager promptly after ventilation is discontinued and submit a completion map no later than the expiration of the 90-day period during which the mine was not ventilated.
Subpart N .... Blasting and Explosives
There is a formal agreement between MSHA and the BATF relative to compliance inspections of surface explosives storage facilities. These inspections will determine compliance with both MSHA surface standards and requirements in 27 CFR Part 55. Procedures covered by this agreement can be found in the General Inspection Handbook.
75.1310 Explosives and Blasting Equipment
Permissible cap lamp batteries approved as shot-firing units are approved to fire single shots only.
Single-Shot Blasting Units approved under any Schedule except Schedule 12D are not permissible blasting units and must be removed from the mine.
75.1316 Preparation Before Blasting
Paragraph (d) of 30 CFR 75.1316 addresses blasting activities at approaching working faces when the faces are within 25 feet of each other. Some concerns have been expressed as to whether this provision restricts mining of crosscuts to one direction only. This paragraph recognizes that crosscuts could be developed from both directions simultaneously. It is designed to protect against premature detonation of explosives that can occur by accidentally cutting or drilling into loaded boreholes. The 25-foot limitation is based on the size of cutting machine cutter bar and drill steel lengths currently used by the coal mining industry. The hazard addressed is that if cutting and drilling occur simultaneously at two approaching faces with less than 25 feet of separation, drilling could be completed and borehole loading operations started at one face while cutting or drilling activities continue at the other face. Under these circumstances, limiting mining activities to only one face at a time will prevent accidents resulting from the cutting or drilling at one face contacting loaded boreholes in an approaching face, especially if mine communications fail or when the space separating approaching faces is less than anticipated.
Subpart O .... Hoisting and Mantrips
75.1400 Hoisting Equipment; General
A hoist used to transport person(s) shall comply with the provisions of this Section. The number of person(s) transported or the frequency of which the hoist is used to transport person(s) are not factors for compliance with this Section.
Although scaffolding hoists are not equipped with safety catches, they can comply with personnel hoisting regulations. Safety systems utilizing safety belts attached to independently suspended safety lines by lanyards and rope grabs can be approved by district managers as a no less effective device to be used in lieu of safety catches.
The following guidelines should be used in approving these devices.
- Life lines must be attached to a structural member of
the shaft or collar or surface facility and not to the
hoist rope outrigger.
- Life lines 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.
75.1402 Communication Between Shaft Stations and Hoist Room
A signal code shall be adopted and used, and it should be posted in view of the hoisting engineer and at all places where signals are given.
Signals received by the engineer shall be repeated by the engineer when miners are to be hoisted or lowered.
75.1403 Other Safeguards
The safeguards, in addition to those included as criteria in the Federal Register, may be considered of sufficient importance to be required in accordance with this Section.
It must be remembered that these criteria are not mandatory. If an authorized representative of the Secretary determines that a transportation hazard exists and the hazard is not covered by a mandatory regulation, the authorized representative must issue a safeguard notice, allowing time to comply before a 104(a) citation can be issued. Nothing here is intended to eliminate the issuance of a 107(a) order when an imminent danger exists.
75.1403-3 Criteria - Drum Clutch; Cage Construction
At the bottom of each hoisting shaft and at intermediate landings, a "runaround" should be provided for safe passage from one side of the shaft to the other. This passageway should be not less than 5 feet in height and 3 feet in width.
Ice should not be permitted to accumulate excessively in any shaft where miners are hoisted or lowered.
No person should ride a cage with equipment, supplies, or materials. This does not prohibit the carrying of small handtools, surveying instruments, or technical devices.
75.1403-5 Criteria - Belt Conveyors
The requirements for the transportation of persons on belt conveyors, as outlined in this Section, shall apply when any person is transported on belt conveyors at times other than during the regularly scheduled mantrip operations.
Bare pinch wires are acceptable for stopping and starting belt conveyors used to transport persons, provided that the voltage on such circuits is not more than 12 volts. A pull cord arrangement that will enable any person riding the belt to stop and start it shall be acceptable as compliance. Start switches may be located at intervals of not more than 500 feet along such belt conveyors.
An official or other responsible person designated by him should be in attendance while miners are boarding or leaving belts.
Ample clearance should be provided at conveyor-loadingheads and at conveyor-control panels.
75.1403-6 Criteria - Self-Propelled Personnel Carriers
Self-propelled track equipment should be equipped with sanding devices capable of applying sand to all rails in either direction of travel.
75.1403-7 Criteria - Mantrips
The following shall be adopted as additional policy to govern the use of "scoop tractors" when transporting persons:
- Underground personnel may be transported in a scoop that is in the rear position according to the direction of travel. In other words, the scoop must be located so that, if a person accidentally fell from the scoop, the tractor would be moving in a direction away from the fallen person.
- A locking device (stiff link or other accepted device) shall be used to preclude the possibility of accidental activation of the hydraulic control lever which operates the scoop.
- If the scoop is equipped with an ejector blade, the control lever for the blade must also be locked in the neutral position.
- Mantrip passengers should not ride under unguarded trolley wire unless suitable covered man-cars are used.
- Failure to provide special locking devices on drop- bottom cars used for transporting miners on mantrips shall be considered to constitute a danger that a mantrip accident will occur immediately or before such danger can be eliminated within the meaning of Section 107(a) of the Act.
Rails should be secured at all joints by means of plates or welds.
75.1403-9 Criteria - Shelter Holes
Upon the approach of moving traffic, persons shall take refuge in shelter holes or other places of safety.
75.1403-10 Criteria - Haulage; General
During inspections of mines where reflectors or other devices are being used in lieu of permissible trip lights, the inspector should determine if approval to use the reflectors or other type device has been granted by the district manager. In the event approval has not been granted, a safeguard notice should be issued.
Back poling should be prohibited except at places where the trolley pole cannot be reversed or when going up extremely steep grades, and then only at very slow speeds.
Main haulage roads are interpreted to be: (1) the road leading from the surface to the section of a one-section mine; and (2)the road leading from the surface into a multi-section mine,including the roads leading to the various sections of the mine.
Exceptions to main haulage roads are sidetracks or branch lines of limited distance which are not ordinarily used for through traffic. Sidetracks, branch lines, etc., may or may not extend from any main haulage road. Therefore, a main haulage road, as referred to in paragraph (b), is a roadway used for the transportation of personnel, equipment, materials, supplies and/or other articles taken into or out of a coal mine, or section of a coal mine, regardless of alternate methods used to transport coal from the working faces and regardless of the size of the mine. Any branch track leading to a nearby installation(pump, compressor, etc.), crosscut, or pillar place is considered as an exception to main haulage roads.
Sprinkling a shuttle car haulage road to allay dust shall not be construed as making the roadway wet and increasing the difficulty of controlling the shuttle car.
Abrupt changes in vertical clearance that present a hazard to persons riding on mobile equipment should be eliminated where possible. Otherwise, signs, preferably luminous, shall be posted to warn of the change in clearance.
New overcasts and similar structures installed on haulageway should be constructed so as to provide the same vertical clearance as the surrounding area or to permit operation of haulage equipment without restricting the operators' or passengers' normal position.
Material being transported should be so loaded and protected that there is no danger to the motorman or brakeman from sliding of equipment and material. Except in emergencies, timbers and other materials not necessary for, or not incidental to, the operation of locomotives, cutting machines, loading machines, and coal-drilling machines should not be transported on such equipment.
Track locomotives should be equipped with proper rerailing devices, safe seating facilities for the operator, audible warning devices, sealed-beam headlights or the equivalent on each end, a suitable lifting jack and bar, and properly installed and maintained sanding devices.
No person should get on or off moving locomotives or cars being moved by locomotives; however, the brakeman may get on or off the rear end of a slowly moving trip.
Standing cars on any track, unless held effectively by brakes,should be properly blocked or spragged. Cars shall be secured effectively at working faces.
Where it is clear at a particular mine that self-propelled,track-mounted, or rubber-tired equipment that is used to transport miners is operating on grades so steep that the ratio of the gear train is not sufficient to prevent movement of the equipment when it is parked, inspectors should determine the operator's method of preventing accidental movement. It should be noted that devices which trap hydraulic fluid, such as the"MICO Leverlock," are sometimes being used as parking brakes.This type of device is not suitable for use as a parking brake because pressure may be lost due to fluid leakage or contraction when it cools, allowing the vehicle to move. If the operator does not use a reliable method of preventing accidental movement of parked equipment, then a notice to provide safeguard under this section should be issued. Generally, the notice should indicate that the operator shall take reliable precautions against accidental movement of the affected equipment when it is parked. Inspectors should allow operators flexibility in providing the necessary precautions, while at the same time making it clear what constitutes compliance with the safeguard notice. Many manufacturers of mining equipment now have available parking brake systems for personnel carriers.
Where an inspector determines that a safeguard notice is necessary in order to address a transportation hazard, the specific safeguard requirements are to be determined by the inspector based on the actual, specific conditions or practices that constitute a transportation hazard at that particular mine.The inspector should document either in the notice or in the inspector's notes the conditions which provide the basis for the issuance of the safeguard notice. The safeguard notice should also identify the nature of the hazard to which it is directed.For example, if a notice to provide safeguards is issued to require a specific minimum clearance distance between pieces of haulage equipment, the safeguard should also include a statement of the hazards that the clearance distance is intended to prevent, such as injury to equipment operators from pieces of rib coal which could be knocked loose or, if the area is a walkway,injury to pedestrians by the equipment due to insufficient clearance.
Service brakes and parking brakes on personnel carriers must be maintained in an operative condition. Accordingly, such brakes that have been allowed to deteriorate into an inoperative condition constitute a violation of Section 75.1725. Emergency and parking brakes that are not installed and maintained on rubber-tired haulage equipment or parking brakes not installed and maintained on other face equipment would constitute a violation of Section 75.523-3.
Where block signals are used, not more than one locomotive,except pushers, should operate in any signal block at the same time unless by special authority. All mine traffic should be under the direction of a person(s) designated by the operator,and no traffic should be in transit without prior clearance,verbally or by use of block signals.
Where seating facilities are provided, operators of equipment should be seated while such equipment is being operated.
This section shall be used to require audible warning devices on all self-propelled equipment, including off-track equipment.Such devices shall be of the type provided by the manufacturer of the equipment and shall be maintained in operative condition.
Self-propelled, rubber tired haulage equipment shall be equipped with sealed-beam lights.
Rubber-tired, battery-powered mine tractors should be equipped with a suitable lifting jack and bar adequately secured or carried in a compartment.
Since controls meeting the requirements of paragraph (m)are available, future notices to provide safeguards or 104(a)citations shall not give more than 30 days for compliance.