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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) > 57.12050—Installation of trolley wires.
57.12050—Installation of trolley wires.
Trolley wires shall be installed at least seven feet above rails where height permits, and aligned and supported to suitably control sway and sag.