A. Electrical equipment that is taken into or used inby the last open crosscut or in other than an intake airway constitutes permissible equipment.
B. Permissible equipment that is used in an area specified in subsection A shall be maintained in permissible condition.
C. No electrical equipment shall be taken into or operated in any place where a methane level of one percent or more is detected.
D. Voltage limitations for underground installations of electrical equipment using direct or alternating current shall conform to the voltages provided in 30 C.F.R. § 18.47.
E. Electrical equipment shall be classified as permissible and shall be maintained in a permissible condition when such equipment is located within 150 feet of any pillar workings or longwall face.
F. Any electrical conductors and cables installed in or inby the last open crosscut, or within 150 feet of any pillar workings or longwall face, shall be:
1. Shielded high-voltage cables supplying power to permissible longwall equipment or other equipment;
2. Interconnecting conductors and cables of permissible longwall equipment;
4. Cables and conductors supplying power to low-voltage or medium-voltage permissible equipment.
G. Electrical equipment shall be maintained in safe operating condition at all times while it is being used, and any unsafe condition shall be corrected promptly or the equipment shall be removed from service.