30 C.F.R. § 57.22233 Actions at 0.5 percent methane (I-C mines).
Title 30 - Mineral Resources
If methane reaches 0.5 percent in the mine atmosphere, ventilation changes shall be made to reduce the level of methane. Until methane is reduced to less than 0.5 percent, no other work shall be permitted in affected areas. [52 FR 24941, July 1, 1987; 52 FR 27903, July 24, 1987]
Title 30: Mineral Resources
PART 57—SAFETY AND HEALTH STANDARDS—UNDERGROUND METAL AND NONMETAL MINES
Subpart T—Safety Standards for Methane in Metal and Nonmetal Mines
Ventilation
§ 57.22233 Actions at 0.5 percent methane (I-C mines).
