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CFR > Title 30 - Mineral Resources > CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR > SUBCHAPTER K—METAL AND NONMETAL MINE SAFETY AND HEALTH (parts 56 to 58) > PART 57—SAFETY AND HEALTH STANDARDS—UNDERGROUND METAL AND NONMETAL MINES > SUBPART K—Electricity (§57.12001 to §57.12088) > 57.12053—Circuits powered from trolley wires.
57.12053—Circuits powered from trolley wires.
Ground wires for lighting circuits powered from trolley wires shall be connected securely to the ground return circuit.