Respirable quartz: Geometric mean exposures and percent exceeding designated occupational exposure limits by major industry division, MSHA and OSHA samples, 1979-2003
SIC - Standard Industrial Classification PEL - permissible exposure limit REL - recommended exposure limit
Note: Before March 1, 1989 and after March 22, 1993, the OSHA PEL is [(10 mg/m3) / (% quartz + 2)], for respirable dust containing at least 1 percent quartz. From March 1, 1989 to March 22, 1993, the OSHA PEL was 0.1 mg/m3 for respirable quartz. The NIOSH REL
Source: MSHA metal/nonmetal mine data. OSHA Integrated Management Information System.
Reference Number: 2008-305
Date Posted: June 2008