(a)All power circuits entering a mine shall be protected against lightning by lightning arrestors at or near the points of entrance to the mine. All power circuits shall be protected against lightning or other surges by adequate circuit breakers, fuses, or both.
(b)All power wires, except trailing cables and ground wires, whether bare or insulated, shall be supported on well-installed insulators and shall not touch combustible material, roof, or ribs. Power wires or cables installed prior to August 12, 1949, in locations inaccessible without prohibitive expense may be continued in use if approved by the division.
(c)Power wires shall be insulated properly when passing through doors and stoppings and where they cross other power circuits.
(d)Signal wires and telephone wires shall be run
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(a) All power circuits entering a mine shall be protected against lightning by lightning arrestors at or near the points of entrance to the mine. All power circuits shall be protected against lightning or other surges by adequate circuit breakers, fuses, or both.
(b) All power wires, except trailing cables and ground wires, whether bare or insulated, shall be supported on well-installed insulators and shall not touch combustible material, roof, or ribs. Power wires or cables installed prior to August 12, 1949, in locations inaccessible without prohibitive expense may be continued in use if approved by the division.
(c) Power wires shall be insulated properly when passing through doors and stoppings and where they cross other power circuits.
(d) Signal wires and telephone wires shall be run at a safe distance and, where possible, shall be placed on the opposite side of the slope or heading from the power wires.
(e) Where track is used as a power conductor:
(1) Tracks shall be bonded and cross-bonded in such manner as to assure adequate return.
(2) Switches on entries shall be well bonded.
(f) Employees called upon to do work on energized electric circuits or energized parts of electrical equipment shall use properly tested lineman’s electric gloves and leather protector gloves.
(g) Trolley and feeder wires shall be installed as follows:
(1) Aligned properly and where installed after August 12, 1949, at least six inches outside the track gauge line.
(2) Provided with cutout switches at intervals of not more than 2,000 feet and near the beginning of all branch lines.
(3) Kept taut and not permitted to touch roof, rib, or cross bars. Particular care should be taken where they pass through door openings to preclude bare wires coming in contact with combustible material.
(4) Trolley or bare feeder cables shall be guarded adequately where it is necessary for men to pass or work under them regularly unless the wires are more than six and one-half feet above the top of the rail. They shall also be guarded adequately on both sides of doors and regardless of height at all stations designated for loading and unloading of mantrips and at sand boxes.