Skip to content
DOL Press Release - MSHA/ 05-975-NAT
U.S. Department of Labor
Contact: Suzy Bohnert    Dirk Fillpot
Phone: (202) 693-9420    (202) 693-4676


Released Monday, June 6, 2005

MSHA Issues Final Rule Strengthening Protections for Underground Metal/Nonmetal Miners Exposed to Diesel Particulate Matter

ARLINGTON, Va. - The U.S. Department of Labor's Mine Safety and Health Administration (MSHA) today issued a final rule strengthening protections for miners exposed to diesel particulate matter (DPM) from diesel exhaust in underground metal and nonmetal mines. By changing the unit of measure for DPM exposure to a more accurate one, this rule allows MSHA to enforce protections more effectively for exposed miners.

"The health and safety of workers is a top priority of this Administration, and this is one more way to demonstrate that commitment," said David G. Dye, acting assistant secretary of labor for mine safety and health.

This rule revises the interim DPM concentration limit measured in total carbon to a comparable, but more accurate, permissible exposure limit measured in elemental carbon. This will help ensure that individual miners are not exposed to unacceptable levels of DPM. The former interim level was 400 micrograms of total carbon per cubic meter of air (400TC/m3). The new interim level is 308 micrograms of elemental carbon per cubic meter of air (308EC µg/m3).

This rule also gives mine operators additional tools to bring their operations into compliance by employing the "hierarchy of controls" that is used in MSHA's other exposure-based health standards for metal and nonmetal mines. However, the rule retains the prohibition on rotation of miners to achieve compliance.

To view the full text of the final rule, visit MSHA's Web site at www.msha.gov. MSHA strives to ensure the safety of miners by helping mine operators nationwide comply with all agency requirements and regulations.