Respirable Dust Trends in Coal Miners With Longwall or Continuous Miner Sections.
Watts-WF Jr.; Niewiadomski-GE
Part 1 VIIth Int'l Pneumoconioses Conf U S Pub Health Serv Cent -Disease Con PP 94-99 :94-99
Over the past 5 years, operators of longwall shearer sections reported increases in median production from 1,200 to 2,200 tons per shift. This increase in production was accompanied by a continuing problem with respirable dust despite the significant decrease in mean dust levels that has occurred since fiscal year 1978 (fy78). A number of longwall sections still experience difficulty in maintaining continuous compliance with the federal standard. Longwall sections have arithmetic mean respirable dust concentrations that are more than double the concentrations reported by continuous ripper sections (2.0 Mg/m3 versus 1.0 Mg/m3). In fy 87, 45 pct (58) of the longwall sections were found to be in noncompliance once, and an additional 24 pct (31) were cited two or more times. Thus, 69 pct of the longwall sections in operation during fy 87 experienced compliance problems. It is evident from these data that dust problems continue to plague longwall mining operations as longwall production continues to rise. If more high- producing longwalls are to be brought on-line to realize the full potential of this mining method, additional effective dust control measures must be put into place and maintained to more consistently control dust levels on a continuous basis.
Part 1, VIIth Int'l Pneumoconioses Conf. U.S. Pub. Health Serv. Cent.-Disease Con., PP. 94-99