30 C.F.R. § 57.4131 Surface fan installations and mine openings.
Title 30 - Mineral Resources
(a) On the surface, no more than one day's supply of combustible materials shall be stored within 100 feet of mine openings or within 100 feet of fan installations used for underground ventilation. (b) the one-day supply shall be kept at least 25 feet away from any mine opening except during transit into the mine. (c) Dry vegetation shall not be permitted within 25 feet of mine openings.
Title 30: Mineral Resources
PART 57—SAFETY AND HEALTH STANDARDS—UNDERGROUND METAL AND NONMETAL MINES
Subpart C—Fire Prevention and Control
Prohibitions/Precautions/Housekeeping
§ 57.4131 Surface fan installations and mine openings.
