30 C.F.R. § 57.22608 Secondary blasting (I-A, II-A, and V-A mines).
Title 30 - Mineral Resources
Prior to secondary blasting, tests for methane shall be made in the mine atmosphere at blast sites by a competent person. Secondary blasting shall not be done when 0.5 percent or more methane is present.
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
Explosives
§ 57.22608 Secondary blasting (I-A, II-A, and V-A mines).
