Respirable quartz: Geometric mean exposures by major industry division, MSHA and OSHA samples, 1979-2003
PEL - permissible exposure limit REL - recommended exposure limit mg/m3 - milligrams per cubic meter MSHA - Mine Safety and Health Administration
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. For metal/non
Source: MSHA metal/nonmetal data. OSHA Integrated Management Information System.
Reference Number: 2008-303
Date Posted: June 2008