Aggreg Manag 2004 Jul/Aug; 9(4):12-14
Many workers in the United States and abroad are exposed to high respirable dust levels as they operate heavy equipment while performing many different duties and job functions in the mining industry. Since much of the Earth's surface contains silica-bearing strata, these workers are also often exposed to high levels of respirable silica dust. A review of Mine Safety and Health Administration dust records reveals that a substantial number of equipment operators exceed the allowable limit for silica and respirable dust while operating this equipment. Often in the mining industry, this equipment is older and various components on the enclosed cab and the filtration system have deteriorated to where they are no longer effective. Another contributing factor identified during a recent field study performed by the National Institute for Occupational Safety and Health was that a significant amount of dust may be generated inside the enclosed cab by the actions of the equipment operator. When this occurs, the only method to effectively remove the dust is with a recirculation filtration system. To this end, a new self-contained recirculation unit designed for the mining industry was tested at two operations. Results of the tests, along with the critical factors for implementing an effective recirculation system for enclosed cabs, are discussed in this article.
Respirable-dust; Silica-dusts; Equipment-operators; Dust-exposure; Mining-industry; Filtration; Dusts; Enclosed-cabs; Air-quality; Coal-mining; Surface-mining; Air-flow
NIOSH Pittsburgh Research Laboratory, P.O. Box 18070, Pittsburgh, PA 15236
Research Tools and Approaches: Control Technology and Personal Protective Equipment