30 C.F.R. § 57.22602 Blasting from the surface (I-C mines).
Title 30 - Mineral Resources
(a) All blasting shall be initiated from the surface after all persons are out of the mine and any connecting mines. (b) Persons shall not enter the mine until a competent person has examined the blast sites and methane concentrations are less than 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
Explosives
§ 57.22602 Blasting from the surface (I-C mines).
