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Final Rule: Respirable Crystalline Silica - Health Alert

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HEALTH ALERT

Final Rule: Respirable Crystalline Silica

On April 18, 2024, MSHA issued its final rule, Lowering Miners’ Exposure to Respirable Crystalline Silica and Improving Respiratory Protection, to reduce miner exposures to respirable crystalline silica and improve respiratory protection for all airborne hazards.

Important Dates:

  • The final rule will take effect on June 17, 2024.
  • Coal mine operators are required to be compliant by April 14, 2025
  • MNM mine operators are required to be compliant by April 8, 2026

The Final Rule:

  • Establishes a uniform permissible exposure limit (PEL) of 50 micrograms per cubicmeter of air (μg/m3) and action level of 25 μg/m3 for all mines.
  • Uniform requirements for monitoring and controlling respirable crystalline silicaRequires medical surveillance at MNM mines, modeled after existing requirements forcoal mines.
  • Updates the existing respiratory protection requirements to the ASTM F3387-19Standard.

For more information, visit: www.msha.gov/regulations/rulemaking/silica