OSHA has a Permissible Exposure Limit (PEL) for exposure to respirable crystalline silica of 50 micrograms per cubic meter of air (µg/m3) based on an 8-hour time weighted average. OSHA also requires hazard communications training for workers exposed to crystalline silica, as well as a respiratory protection program until engineering controls are implemented.
In September 2008, CalOSHA issued a standard “Control of Employee Exposures from Dust-Generating Operations Conducted on Concrete or Masonry Materials.”
In December, 2004, New Jersey signed a law prohibiting the dry cutting and dry grinding of masonry.
NIOSH recommends an exposure limit lower than the OSHA PEL. The NIOSH Recommended Exposure Limit (REL), published in 1974, is 0.05 mg/m3 based on a time-weighted average for up to 10 hours.
The American Conference of Industrial Hygienists (ACGIH) recommends a Threshold Limit Value of 0.025 mg/m3 based on an 8-hour time-weighted average.
Federal OSHA Standards
are enforced by the U.S. Department of Labor in 26 states. There are currently 22 states and jurisdictions operating complete
State plans
(covering both the private sector and state and local government employees) and 5 - Connecticut, Illinois, New Jersey, New York and
the Virgin Islands - which cover public employees only. If you are working in one of those states or jurisdictions you should ensure
that you are complying with their requirements.