A system for asphalt fume generation.
Stone S; Goldsmith T; Afshari A; Frazer D
Biomedical engineering recent developments: proceedings of the Twenty First Southern Biomedical Engineering Conference, September 28 - 29, 2002, Bethesda, Maryland. Vossoughi J, ed. Washington, DC: Medical and Engineering Publishers, Inc., 2002 Sep; :321-322
There is concern during road paving operations over the potential adverse health effects from exposure to asphalt fume. In order to study this problem a system was developed to expose small laboratory animals to a precisely controlled concentration of asphalt fumes. The fumes were generated as asphalt flowed over a heated metal plate and were entrained in heated conditioned air, which passed over the plate. After passing though the generator, the fume entered the exposure chamber through a heated pipe. The mass concentration of the fume aerosol within the chamber was estimated with a light scattering device and was used to control the amount of heated, conditioned diluent air that was added to the fume to maintain its concentration within desired limits. A second feedback system used a computer controlled needle value to regulate. the flow of asphalt across the metal plate. Additional control systems were used to sustain constant airflows and temperatures throughout the system. Specialized software. was developed to continuously monitor and record temperatures, gas flows and fume concentration within the system for analysis. Laboratory generated asphalt fume was shown to be similar to field fume in terms of chemical composition.
Asphalt-fumes; Exposure-chambers; Exposure-methods; Laboratory-equipment; Laboratory-techniques
Biomedical engineering recent developments: proceedings of the Twenty First Southern Biomedical Engineering Conference, September 28 - 29, 2002, Bethesda, Maryland