Measurement and control of diesel exhaust aerosol.
Cantrell BK; Waytulonis RW; Ambs JL
Proceedings of the 22nd Annual Institute on Coal Mining Health, Safety and Research, Blacksburg, Virginia, August 26-28, 1991. Hugler E, Bacho A, Karmis M, eds. Blacksburg, VA: Virginia Polytechnic Institute and State University, 1991 Aug; :73-85
During the 1980's, the Mine Safety and Health Administration (MSHA.) proposed new regulations for the use of diesel equipment in underground coal mines. In addition, the National Institute for Occupational Safety and Health (NIOSH) recommended that whole diesel exhaust be regarded as "a potential occupational carcinogen," and that reductions in exposure to exhaust pollutants would reduce excess risk. In this period, the U.S. Department of the Interior, Bureau of Mines (Bureau), developed and tested new diesel emission measurement techniques and exhaust control technology. Threshold limit values (TLVs) have been recommended for diesel-associated gaseous pollutants; CO, CO2, NO, N02, S02, and some hydrocarbons (HC) emitted in diesel exhaust. There is, however, no TL V recommended for diesel exhaust aerosols nor is there yet a standard method for sampling these aerosols. The Bureau and the University of Minnesota have developed a personal diesel exhaust aeroso] sampler. Air-quality measurements made during field tests of this sampler indicate that average diesel exhaust aerosol concentrations in the haulage entry for the mines surveyed were 0.8 +/- 0.2 mg/m3. Also, gas concentrations, i.e., CO, CO2, NO, NO2, and SO2, were well below regulated levels. Emission controls for underground diesel vehicles include work practices, engine maintenance, and exhaust aftertreatment. Work practices to control or minimize diesel exhaust pollutants begin with the use of engines known to have good emission characteristics. Engine manufacturers have developed diesels to be a balance of performance, durability, and emissions. Deviation from proper engine maintenance methods and intervals results in poor performance, increased engine wear, and higher emissions. Exhaust aftertreatment controls are used to modify exhaust characteristics and remove pollutants. Waterbath exhaust conditioners, water scrubbers, are currently used to provide cooling and prevent flames, sparks, or backfires reaching gassy atmospheres. They also remove between 10 and 30 pet of exhaust aerosol and a high percent of sulfates. Oxidation catalytic converters oxidize CO and RCs into Jess toxic gases. Catalyzed and noncatalyzed ceramic diesel aerosol filters are used on selected heavy-duty diesel vehicles in noncoal mines. These are 80 to 95 pct efficient in removing exhaust aerosol. Catalyst coating son diesel exhaust filters reduce regeneration temperatures and have effects upon gaseous emissions similar to the coatings on catalytic converters. The Bureau has recently completed tests of a disposable, pleated-media diesel exhaust aerosol filter conducted at a high altitude coal mine in Utah. Filters were shown to reduce diesel exhaust aerosol concentration in the mine environment by 95 +/- 4 pct.
Mine-workers; Miners; Mining-industry; Pollutants; Pollution; Toxic-materials; Toxins; Control-methods; Control-systems; Diesel-exhausts; Diesel-emissions; Diesel-engines; Carcinogens; Aerosols; Exhaust-gases; Filters; Underground-mining; Underground-miners; Coal-workers; Coal-miners; Coal-mining
Hugler E; Bacho A; Karmis M
Proceedings of the 22nd Annual Institute on Coal Mining Health, Safety and Research, Blacksburg, Virginia, August 26-28, 1991