Final rule · 2026-23050

Improving and Eliminating Regulations; Limit on Exposure to Diesel Particulate Matter in Underground Metal and Nonmetal Mines

MSHA is eliminating outdated requirements for diesel particulate matter (DPM) personal exposure limits for underground metal and nonmetal (MNM) mines. These requirements are being removed from MSHA's regulations because they contain outdated effective dates and exposure limits that are no longer applicable.