An Update of the Reduced Standards Problem and Overview of Improved Control Technology for Respirable Coal Mine Dust.
Jankowski-RA; Kissell-FN; Nesbit-RE
Proc 2nd U S Mine Ventilation Symp Reno Nevada, Sept 23-26 1985 :151-167
Over 10 pct of active coal mine sections are on reduced dust standards owing to quartz, with an average applicable standard for the underground designated occupation at 1.2 Mg/m3, while the applicable standard for the surface designated work position averages 0.8 Mg/m3. It is estimated that by the end of the 1985 fiscal year over 15 pct of all coal mine workers will be affected by overexposure to respirable quartz and that a significant percentage of mining sections will be placed under more stringent dust standards. Studies have shown that the primary source of quartz dust on surface mining operations comes from dust escaping the collector system of the highwall drill. On underground operations, the primary source of quartz is the continuous mining machine, cutting roof, floor and rock partings in the seam. With the cooperation of industry and the Mine Safety and Health Administration, the Bureau of Mines has identified new or improved controls to reduce the amount of airborne dust and dust rollback and developed procedures to correct the deficiencies of the roof bolter dust collector system. The Bureau has also initiated extensive research to control the quartz dust exposure of the continuous miner operator, to control quartz dust levels downwind of the continuous mining machine, and to identify novel concepts for reducing quartz dust in underground coal mines.
Proc. 2nd U.S. Mine Ventilation Symp., Reno, Nevada, Sept. 23-26, 1985, PP. 151-167