Mining Publication: Criteria for a Recommended Standard: Occupational Exposure to Respirable Coal Mine Dust: Occupational Exposure to Respirable Coal Mine Dust

Information regarding adverse health effects resulting from exposure to respirable coal mine dust was reviewed as a basis for the development of new occupational safety and health standards. Evidence indicated that coal mine dust exposures over a working lifetime may result in the development of simple coal workers' pneumoconiosis, progressive massive fibrosis, and chronic obstructive pulmonary disease. Based on epidemiology studies, a working lifetime exposure to levels of coal dust at the current Mine Safety and Health Administration permissible exposure limit of 2mg/m³ increased the risk of developing these disorders. When exposure also occurs to crystalline silica (14808-60-7) at respirable size particles, the danger of developing silicosis or mixed dust pneumoconiosis was also present. NIOSH recommends in this report that the exposures to respirable coal mine dust be limited to 1mg/m³ as a time weighted average concentration for up to 10 hours a day during a 40 hour work week. Recommendations are provided concerning respirable coal mine dust sampling to monitor worker exposure, the proper use of personal protective equipment, and medical screening and surveillance examinations.