30 C.F.R. § 57.5045 Posting of inactive workings.
Title 30 - Mineral Resources
Inactive workings in which radon daughter concentrations are above 1.0 WL, shall be posted against unauthorized entry and designated by signs indicating them as areas in which approved respirators shall be worn.
Title 30: Mineral Resources
PART 57—SAFETY AND HEALTH STANDARDS—UNDERGROUND METAL AND NONMETAL MINES
Subpart D—Air Quality, Radiation, Physical Agents, and Diesel Particulate Matter
Radiation—Underground Only
§ 57.5045 Posting of inactive workings.
