Improvement of Rate Quality Control Method in Identifying HazardousLocations

摘要

Hazardous locations are sites with higher than expected frequency, rate, or severity of crashes. Identifying hazardous locations is used in deducing underlying causal factors and implementing potential countermeasures. A summary of typical methods for identifying hazardous locations and the associated problems are provided. The emphasis is placed on the rate quality control method. A brief historical perspective on the development of the rate quality control method, its use in identifying hazardous locations, and its strengths and weaknesses are presented. The limitation of collected data from similar locations is discussed. An improvement is provided to estimate the crash rate at the treated site where it is difficult to get locations with similar characteristics associated with the rate quality control method. The improvement is combining the rate quality control method with the Safety Performance Function (SPF), which accounts for factors which probably have close relationships to the crash rate at the treated site and the reference sites. A case study is briefly described to show the improvement.