The present study used commercial motor vehicle (CMV) crash data from NCDOT’s Traffic Engineering Accident Analysis System (TEAAS) to infer the presence and relative extent of STAA dimensioned vehicles operating beyond the 3-mile buffer of the present STAA Truck Network in North Carolina. STAA dimensioned vehicles include trailers 53ft or greater in length and double trailers. STAA routes in NC constitute only about 8 percent of all state-maintained roadway miles. The data showed that approximately 87 percent of all large truck crashes took place on STAA network roads during the period 2001-2005. While only 13 percent of large truck involved crashes took place on roads "off" the network, the likelihood of any given off-network crash involving a fatality was twice that of a crash taking place on the network. Off network crashes involving large trucks are problematic for reasons other than safety, especially in metropolitan areas where operations, irrespective of crash involvement, are associated with traffic delays (due to the maneuvering/turning requirements of larger vehicles) and infrastructure damage. The report provides GIS "maps" of each of the eight NCSHP troop areas, the network and its 3-mile buffer and the location and severity of all large truck-involved crashes reported as taking place "off' the network. The report also provides a detailed description of the attributes of off-network crashes for 2001-2005 for each NCSHP troop. Several criteria were explored as a means for ranking troop areas in terms of need for STAA improvements. The report also identifies specific off-network routes at the county and troop levels having the highest numbers of crashes per mile. Recommendations are provided for `next steps’ as well as a plan for technology transfer and implementation.
