MSHA’s Proposed Rule to Heighten Standards Relating to Respirable Crystalline Silica
July 5, 2023
By: Eric R. Holway
On June 30, 2023, the Mine Safety and Health Administration (“MSHA”) made publicly available a proposed rule that would amend existing federal standards with respect to occupational exposure to respirable crystalline silica, or silica dust. The stated purpose of the proposed rule is to better protect miners against occupational exposure to silica dust and improve respiratory protection for all airborne hazards. The proposed rule has been under discussion for the past few years, and it comes as no surprise to the mining industry. As expected, the proposed rule significantly reduces the respirable crystalline silica Permissible Exposure Limit (“PEL”).
The proposed rule would require mine operators to maintain the PEL for respirable crystalline silica at or below 50 µ/m3, calculated as an eight-hour time-weighted average. The rule applies to coal and metal/nonmetal mine operations. Mine operators would need to use engineering controls and, if necessary, administrative controls to meet the requirements of the proposed PEL. If a miner’s exposure exceeds the proposed limit, mine operators would be required to take immediate corrective actions to come into compliance.
Under the proposed rule, mine operators would be required to conduct baseline sampling within the first 180 days after the effective date of the proposed rule to assess the respirable crystalline silica exposure of each miner who is or may reasonably be expected to be exposed to respirable crystalline silica. Periodic sampling may be required, depending on the results of the most recent sample.
Additionally, the proposed rule includes other requirements for the provision of medical surveillance for metal and nonmetal miners. The proposed medical examinations would include chest X-rays, spirometry, symptom assessment, and occupational history, which must be provided at no cost to the miner.
The proposed rule would also replace existing requirements for respiratory protection to reflect the latest advances in respiratory protection technologies and practices by incorporating “Standard Practice for Respiratory Protection” (ASTM F3387-19), an updated respiratory protection standard for respirable crystalline silica and all other regulated airborne contaminants.
After the proposed rule is published in the Federal Register, public comments will be permitted. MSHA is also expected to announce dates for upcoming public hearings in Arlington, Virginia and Denver, Colorado. These hearings will be open for both in-person or online participation.
A copy of the proposed rule can be viewed here: https://www.msha.gov/sites/default/files/Regulations/Proposed%20Rule.pdf