§71.700. Inhalation hazards; threshold limit values for gases, dust, fumes, mists, and vapors. — Inbound Citations

(b) Upon written notification by the Secretary to the operator of an underground coal mine or of a surface coal mine, the operator shall conduct any additional air sampling tests and analyses as the Secretary may from time to time require in order to ensure compliance with the standards set forth in § 71.700 in each surface installation and at each surface worksite.