Dust Exposures at U.S. Surface Coal Mines in 1982–1983

Abstract
Exposures to British Mining Research Establishment corrected respirable dust and respirable quartz at U.S. surface coal mines during 1982–1983 were evaluated from coal mine operator and Mine Safety and Health Administration (MSHA) inspector samples. The average respirable quartz concentration from inspector samples ranged from .34-.49 mg/m3 for drilling jobs and .18 mg/m3 for bulldozer operators. For most other surface coal mine jobs, the average respirable quartz concentration was less than .1 mg/m3, and the average respirable dust concentration was less than 2 mg/m3. The results from the analysis of quartz exposures are consistent with epidemiological results for an increased silicosis risk among drillers. It is unclear, however, whether the MSHA samples provide a representative estimate of the average annual quartz concentration for drillers. Results suggest the need for a greater number of quartz samples to be taken on strip coal miners, particularly on drillers and bulldozer operators.