A heavy-duty vehicle visual classification scheme: Heavy-duty vehicle reclassification method for mobile source emissions inventory development

When a state air quality agency undertakes regional transportation and air quality plans, it must conform to a mobile source emissions budget in a state implementation plan through mobile source emissions inventories. To avoid problems associated with using the current EPA conversion guidance, Georgia Tech (GT) researchers developed a new visual heavy-duty vehicle (HDV) classification scheme (X-scheme), which was the modified scheme of the GT HDV visual classification scheme developed in 1999 for use in collecting onroad field data, for use in allocating observed vehicle volumes to applicable MOBILE6 vehicle classes. Each HDV classification scheme has its own usefulness for their own propose; that is that the EPA scheme is for emissions modeling, the FHWA scheme is for highway traffic management, and the GT HDV visual classification scheme is for vehicle activity observation. In terms of emissions modeling, a hybrid HDV scheme such as the X-scheme is needed not only for easy vehicle observation, but also for highway perofmrance monitoring systems database development. The X-scheme is useful to observe HDV activities and to convert observed activities to EPA HDV classes with high resolution for the emissions modeling. This is an abstract of a paper presented at the AWMA 97th Annual Conference and Exhibition (Indianapolis, IN 6/22-25/2004).