Respirable quartz: Geometric mean exposures and percent exceeding designated occupational exposure limits by MSHA coal mine district and state, MSHA inspector and mine operator samples, 1982-2003
- indicates incalculable field. PEL - permissible exposure limit REL - recommended exposure limit GM
Note: The MSHA PEL is 2 mg/m3 MRE for respirable dust containing less than or equal to 5 percent quartz. The PEL is adjusted using the formula [(10 mg/m3 MRE) / (% quartz)] for respirable dust containing greater than 5 percent quartz. See appendices for sourc
Source: MSHA coal mine inspector and mine operator quartz data.
Reference Number: 2007T03-18
Date Posted: June 2008