CFR > Title 30 - Mineral Resources > CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR > SUBCHAPTER O—COAL MINE SAFETY AND HEALTH (parts 70 to 90) > PART 75—MANDATORY SAFETY STANDARDS—UNDERGROUND COAL MINES > SUBPART L—Fire Protection (§75.1100 to §75.1108) > 75.1103-7—Electrical components; permissibility requirements.

75.1103-7—Electrical components; permissibility requirements.

The electrical components of each automatic fire sensor and warning device system shall:
(a) Remain functional when the power circuits are deenergized as required by § 75.706; and
(b) Be provided with protection against ignition of methane or coal dust when the electrical power is deenergized as required by § 75.313, but these components shall be permissible or intrinsically safe if installed in a return airway.

Code of Federal Regulations

[37 FR 16546, Aug. 16, 1972, as amended at 57 FR 20929, May 15, 1992]