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Using Barriers to Reduce Dust Exposure of Longwall Face Workers.
BoM, 1986 :10 pages
Through laboratory and underground studies, the Bureau of Mines has evaluated the use of passive barriers (dust shields) to help confine dust generated by longwall shearers to the face area. Laboratory studies focused first on selection of the optimum barrier design--a simple, gobside barrier (made of conveyor belting) coupled with a headgate splitter arm--to prevent the dust cloud from entering the walkway at the headgate end of the shearer when cutting tail to head. Further laboratory testing was done to determine whether using passive barriers in combination with different water-spray dust-reduction methods, including the shearer-clearer system developed by the Bureau, would improve dust reduction over that from using the water sprays alone. It was found that the combination of gobside passive barriers plus the full shearer-clearer system was most effective, and surmised that this would be especially useful in thicker seams. However, underground testing revealed that the shearer-clearer system alone was 35 pct more effective in reducing dust contamination than when used with the gobside passive barriers, and far more effective than using passive barriers with a conventional water spray system. For such an effective system as the shearer-clearer, the reduction in available space over the top of the machine actually impeded system performance; this was shown in both eastern and western mines. But when used with comparatively inefficient water spray systems, the passive barriers, used in combination with a headgate splitter arm, provide considerable help in reducing
Spray-nozzles; Dust-control; Coal-mining; Underground-mining;
IH; Report of Investigations
NTIS Accession No.
Bureau of Mines, Pittsburgh, Pennsylvania. Pittsburgh Research Center
Page last reviewed: April 12, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division