Respiratory Protection Recommendations for Airborne Exposures to Crystalline Silica
July 2008
DHHS (NIOSH) Publication Number 2008-140
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This document describes the NIOSH policy for respiratory protection against airborne exposures to crystalline silica.
NIOSH recommends the use of half-facepiece particulate respirators with N95 or better filters for airborne exposures to crystalline silica at concentrations less than or equal to 0.5 milligrams per cubic meter of air (mg/m3). The Occupational Safety and Health Administration (OSHA) also specifies the use of at least a 95-rated filter efficiency [29 Code of Federal Regulations (CFR) 1910.134]. The recommendation for a 95-rated filter efficiency reflects the improved filter efficiency of N95 filters over the earlier dust and mist (DM) filters.
Respiratory Protection Recommendations for Airborne Exposures to Crystalline Silica [PDF – 103.34 KB]