30 CFR § 57.4263
Underground belt conveyors.
Fire protection shall be provided at the head, tail, drive, and take-up
pulleys of underground belt conveyors. Provisions shall be made for
extinguishing fires along the beltline. Fire protection shall be of a type,
size, and quantity that can extinguish fires of any class in their early
stages which could occur as a result of the fire hazards present.