A new proposed rule change could better protect U.S. miners from health hazards related to silica dust exposure.
The U.S. Mine Safety and Health Administration (MSHA) announced a proposed rule change June 30, 2023, to amend current standards to ensure miners have the same levels of protection against silica dust as workers in other industries.
Silica dust, or respirable crystalline silica, is a carcinogen and exposures over time cause severe illnesses, including:
- silicosis
- progressive massive fibrosis
- non-malignant respiratory disease, such as emphysema
- kidney disease, and
- lung cancer.
Miners exposed to mixed coal mine dust containing respirable crystalline silica can develop coal workers’ pneumoconiosis, or black lung disease, as well multi-dust pneumoconiosis.
MSHA’s proposed rule change would require mine operators to maintain permissible exposure limits (PELs) to silica dust at or below 50 micrograms per cubic meter of air for a full shift exposure, calculated as an 8-hour time weighted average.
If a miner’s exposure exceeds the limit, the rule would require mine operators to take immediate corrective actions to come into compliance.
The proposed rule includes other requirements to protect miners’ health such as exposure sampling and medical surveillance at no cost for metal and non-metal miners. It would also replace existing outdated requirements for respiratory protection with new requirements that better reflect the latest technological advances and practices.
Once the proposed rule is published in the Federal Register, MSHA will open public comments and announce dates for public hearings in Arlington, Virginia, and Denver, Colorado. The hearings will be open for in-person or online participation.
