Effect of the 2.0 mg/m3 coal mine dust standard on underground environmental dust levels

The 1969 Federal Coal Mine Health and Safety Act established environmental dust standards for underground coal mines. The Act requires that the average concentration of respirable dust in the active workings of a mine be maintained at or below 3.0 mg/m3; and, that effective December 30, 1972, the 3.0 mg/m3 standard be reduced to 2.0 mg/m3. This paper discusses the current status of dust levels in our underground coal mines, the effect of the 2.0 mg/m3 standard on underground dust levels, and associates the current levels with specific operations and occupations. The comparison is made between current levels and those existing prior to December 30, 1972.