30 C.F.R. § 57.22105 Smoking and open flames (IV mines).
Title 30 - Mineral Resources
Smoking or open flames shall not be permitted in a face or raise, or during release of gas from a borehole until tests have been conducted in accordance with §57.22226 and the methane level has been determined to be below 0.5 percent.
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
§ 57.22105 Smoking and open flames (IV mines).
