503 EM 385-1-1 Sections 20-26

26.D.08 Storage of flammable and combustible materials.

3. Flammable or combustible materials must not be stored above ground within 100 ft (30.4 m) of any access opening to any underground operation unless they are located as far as practical from the opening and either a fire-resistant barrier of not less than a 1-hour rating is placed between the stored material and the opening.
4. Electrical installations in underground areas where oil, grease, or diesel fuel are stored must be used only for lighting fixtures.
5. Lighting fixtures in storage areas or within 25 ft (7.6 m) of underground areas where oil, grease, or diesel fuel are stored must be approved for Class I, Division 2 locations > See Section 11.H.

26.D.09 The piping of diesel fuel from the surface to an underground location is permitted only if:

1. Diesel fuel is contained at the surface in a tank whose maximum capacity is no more than the amount required to supply the equipment serviced by the underground fueling station for a 24-hour period;
2. The surface tank is connected to the underground fueling station by an acceptable pipe or hose system controlled at the surface by a valve, and at the shaft bottom by a hose nozzle (nozzle must not be of the latch-open type);
3. The pipe is empty at all times except when transferring diesel fuel from the surface tank to a piece of equipment in use underground; and
4. Hoisting operations in the shaft are suspended during refueling operations if the supply piping in the shaft is not protected from damage.

26.D.10 Any structure located underground or within 100 ft (30.4 m) of an opening to the underground must be constructed of material having a fire-resistance rating of at least 1 hour.

26.D.11 Oil-filled transformers must not be used underground unless they are located in a fire-resistant enclosure and surrounded by a dike to contain the contents of the transformers in event of a rupture.

26.D.12 Noncombustible barriers must be installed below welding or burning operations in or over shaft or raise.

26.E Drilling.

26.E.01 Drilling machines.

> See also Section 18.

1. Employees must not be allowed on a drill mast while the drill bit is in operation or the drill machine is being moved.
2. When drill machines are being moved from one drilling area to another, drill steel, tools, and other equipment must be secured and the mast placed in a safe position.
3. Drills on columns must be anchored firmly before drilling is started and must be retightened frequently.
4. Accessible areas within the swing radius of the rear of the equipment's rotating superstructure, either permanently or temporarily mounted, must be barricaded to prevent an employee from being struck or crushed by the crane and hoisting equipment.
5. Jumbos.
• (1) Safe access must be provided to all working levels of drill jumbos.

• (2) Jumbo decks and stair treads must be designed to be slip-resistant and secured to prevent accidental displacement.
• (3) Only employees assisting the operator must be allowed to ride on jumbos, unless the jumbo meets the requirements for adequate seating arrangements that protect passengers from being struck, crushed, or caught between equipment or surfaces, and has safe access.
• (4) Employees working under jumbo decks must be warned whenever drilling is about to begin.
• (5) On jumbo decks over 10 ft (3 m) in height, guardrails, which are removable, or equal protection must be provided on all open sides, excluding access openings of platforms, unless an adjacent surface provides equivalent fall protection.
• (6) Stair access to jumbo decks wide enough to accommodate two persons if the deck is over 10 ft (3 m) in height.
• (7) Receptacles or racks must be provided for drill steel stored on jumbos.
• (8) The employer must provide mechanical means for lifting drills, roof bolts, mine straps, and other material to the top decks of jumbos over 10 ft (3 m) in height.

26.E.02 Scaling bars must be available at scaling operations and must be maintained in good conditions at all times. Blunted or severely worn bars must not be used.

26.E.03 Blasting holes must not be drilled through blasted rock (muck) or water.

26.E.04 Before commencing the drill cycle after a blast, the face and any remaining blasting holes must be examined for misfires that, if found, must be removed.

26.E.05 Employees in a shaft must be protected either by location or by suitable barriers if powered mechanical loading equipment is used to remove muck containing unfired explosives.

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