{"data":{"id":"us/30-cfr-57.5015","jurisdiction":"us","citation":"30 CFR 57.5015","heading":"Oxygen deficiency.","body":"Air in all active workings shall contain at least 19.5 volume percent oxygen.","path":["Title 30—Mineral Resources","CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR","SUBCHAPTER K—METAL AND NONMETAL MINE SAFETY AND HEALTH","PART 57—SAFETY AND HEALTH STANDARDS—UNDERGROUND METAL AND NONMETAL MINES","Subpart D—Air Quality, Radiation, Physical Agents, and Diesel Particulate Matter"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-30.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:25:24Z","sha256":"cf615e2e5596dd85bc23194fe44e47ef97ede8a975eb4a0ad2ce719e3f1189b0","source_id":"us-cfr","stale":true,"prev":"us/30-cfr-57.5006","next":"us/30-cfr-57.5037"},"notice":"GroundRules: Original legal text. Not legal advice."}