On November 11, 2026, the Mine Safety and Health Administration (MSHA) posted the proposed revised rule entitled Respirable Crystalline Silica and Respiratory Protection. View the proposed rule.

The proposed rule is 186 pages long and does not propose any changes to the respirable crystalline silica PEL of 50 micrograms per cubic meter of air for a full-shift exposure or the action level of 25 micrograms per cubic meter of air for a full-shift exposure. MSHA’s revised rule focuses on “practical, commonsense, risk-based improvements to compliance requirements, exposure monitoring, medical surveillance, recordkeeping, and respiratory protection based on [Occupational Safety and Health Administration] standards.” According to the agency, the proposed rule “would clarify and improve mine operators’ compliance requirements for respirable crystalline silica overexposure and improve respiratory protections and health protections for all miners.”

The rule will be formally published in the Federal Register on November 12, 2026. A 60-day comment period will follow. MSHA is holding a virtual public hearing on December 15, 2026, at 9 a.m. Eastern Time to provide industry, labor, and other interested parties with an opportunity to present oral statements and other information on the proposed rule. Additional information on how to attend the hearing will be available on MSHA’s public hearing information page.

Please reach out to a Husch Blackwell Workplace Safety and Health team member with any questions.