Respirable crystalline silica, or silica dust, is a common occupational hazard for coal and metal/nonmetal (MNM) miners. Silica dust is released through many mining and milling operations, including cutting, drilling, excavating, sanding, and crushing.
Silica dust can be inhaled easily because the dust particles are so small. Once the silica dust particles are inhaled, they may remain in the lung for a long time. Adverse health effects caused by exposure to respirable crystalline silica include silicosis (acute, accelerated, or chronic silicosis and progressive massive fibrosis), lung cancer, nonmalignant respiratory diseases (e.g., emphysema and chronic bronchitis), and kidney disease. Each of these illnesses is chronic, irreversible, and potentially disabling or fatal.
To reduce miner exposures to silica dust and other airborne hazards, MSHA issued a final rule entitled Lowering Miners' Exposure to Respirable Crystalline Silica and Improving Respiratory Protection. This final rule went into effect on June 17, 2024. Coal mine operators must come into compliance with the final rule by April 14, 2025, and MNM mine operators must come into compliance by April 8, 2026.
To assist miners and mine operators in understanding the risks of silica dust and complying with the rule, MSHA offers a range of compliance assistance materials for mine operators, informational materials for miners, and other resources.
For Mine Operators
For Miners
Additional Resources