Measurement of Coal Dust and Diesel Exhaust Aerosols in Underground Mines.
Rubow-KL; Cantrell-BK; Marple-VA
Part I VIIth Int'l Pneumoconioses Conf U S Pub Health Serv Cent -Disease Con Pp 645-50 :645-50
In a cooperative study by the University of Minnesota and the U.S. Bureau of Mines, diesel exhaust and mineral dust concentrations have been measured for aerosols generated in the laboratory and in five underground coal mines. Three mines utilized diesel-powered haulage equipment and two used all-electric equipment. Two source apportionment techniques have been applied to differentiate between the mineral dust and diesel exhaust aerosol concentrations measured. The first technique, using a micro-orifice, uniform deposit impactor (moudi) for size-selective sampling, is based on modeling aerosol size and on the premise that the diesel exhaust portion of the aerosol is predominantly submicrometer and the mineral dust portion is mostly greater than 1 um in size. The second technique, chemical mass balance (cmb) modeling, was used to referee the analysis of diesel exhaust and mineral dust aerosol concentrations from the size-selective sampling results. The moudi size distribution data were modeled to obtain parameters describing the fine and coarse fractions of the sampled aerosol and to estimate the contributions to each mode from both mineral dust and diesel exhaust aerosol sources. The results showed the size distribution of the mixed aerosols exhibited two definite modes with the minimum between the modes occurring at 0.8 Um. Less than 5 pct of the coal mine diesel aerosol was found in the coarse size fraction. Cmb analysis confirms the original premise for using aerosol size to separate diesel exhaust and mineral dust aerosol during sampling. Based on the results
Part I, VIIth Int'l Pneumoconioses Conf. U.S. Pub. Health Serv. Cent.-Disease Con., Pp 645-50