30 CFR §56.6904
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
Smoking and use of open flames shall not be permitted within 50 feet of explosive material except when separated by permanent noncombustible barriers. This standard does not apply to devices designed to ignite safety fuse or to heating devices which do not create a fire or explosion hazard.