Respirable quartz: Geometric mean exposures and percent exceeding designated occupational exposure limits in coal mining, MSHA inspector and mine operator samples, 1982–1999
- indicates incalcuable field SIC - Standard Industrial ClassificationPEL - permissible exposure limitREL - recommended exposure limitGM - Geometric Meanmg/m3 - milligrams per cubic meterMRE - Mining Research EstablishmentMSHA - Mine Safety and Health Administration
Note: For coal mining, the MSHA PEL is [(10 mg/m3 MRE) / (% quartz)] for respirable dust containing greater than 5 percent quartz. The MSHA respirable coal mine quartz exposure data and the NIOSH REL for respirable quartz cannot be compared to each other because they are based on different sampling criteria. See appendices for source description, methods, and agents.
Source: Mine Safety and Health Administration (MSHA) coal mine inspector and mine operator quartz data.
