Section 43.35. Power wires and cables

(a) In all shafts where the angle of inclination is above 45° from the horizontal, and in all hoisting shafts or manway compartments, all power wires and cables shall be amply protected by insulation and substantially fixed in position. All shaft cable shall be supported on insulators that do not cause abrasion of the covering or insulation, and shall be spaced so that no part of the cable is under a tension greater than 1/4 its ultimate strength. The cable shall be held in position at points between the insulators by grips or cleats that do not cause abrasion of the covering or insulation. If the cables are not completely boxed in and protected from falling material, space shall be left between them and the side of the shaft so that they may yield and lessen a blow from falling material. This requirement shall not be construed to prevent the installation of efficiently insulated wires in metal conduit, to transmit power underground.

(b) If it is not possible to keep the cables or feed wires in tunnels at least 12 inches from any part of the tunnel, car or locomotive, they shall be specially protected by proper guards.