The US Federal Highway Administrations (FHWAs) Highway Safety Information System (HSIS) project includes three basic components  (1) the acquisition of annual crash, roadway inventory, traffic and other safety data files from seven states and two local jurisdictions, (2) the preparation of these data into research-usable formats and the on-request distribution of subsets of these data to researchers both inside the US DOT and across the nation for use in their research studies, and (3) the use of these data by HSIS project team researchers in research tasks that support FHWA or companion agencies.

In this case, the HSIS research team was requested by Dr. Michael Griffith, Director of FMCSAs Office of Research and Analysis, to conduct a project which would identify NC Interstate corridors which exhibit a higher than normal number of injury or fatal crashes involving cars and commercial vehicles. (North Carolina is one of the states in the HSIS system, and HSIS contains NC data from 1985  2005.) These identified sites could then be used as potential treatment sites in an enforcement program that is to be conducted by the North Carolina State Highway Patrol (SHP), the Motor Carrier Enforcement Administration Section of the SHP and FMCSA. This enforcement program may be modeled after the Ticketing Aggressive Cars and Trucks (TACT) program conducted in Washington State. The details of that program can be found at http://www.wa.gov/wtsc/programs/trucks/blomberg_final_tact_report.pdf.

This current research effort is only related to one component of the overall TACT effort  the identification of potential sites (corridors) where the enforcement treatment may be implemented and corridors which might be used as comparison sites in a program evaluation. The following narrative will describe how these potential corridors were identified and the results of the effort  the corridor locations. An attempt is being made to make this as non-technical as possible (given that the process used is indeed somewhat technical in a statistical sense). Additional technical details will be included in appendices to this report.