Examination of Existing Tools and Data for Highway Safety Management in Oklahoma

Abstract

As an integral component of transportation asset management, Federal, state and local agencies spend considerable amount of resources on roadway safety management to reduce crashes and fatalities. Currently, most DOTs are collecting roadway safety inventory data on a periodic basis for their Safety Management Systems and several safety management tools such as Highway Safety Manual (HSM), Safety Analyst and Interactive Highway Safety Design Model (IHSDM) have been developed to assist in the safety management process. In this study, a comprehensive literature review on national and state efforts of safety management was conducted and the programs being undertaken to improve roadway safety in Oklahoma were summarized. Available tools for safety management, their data needs and their applications were overviewed. Thereafter, an analysis of the goodness-of-fit of the crash prediction model in HSM and IHSDM were evaluated with historical Oklahoma crash data on rural and urban roadway segments. Subsequently, rigorous statistical analysis was performed with the Poisson regression model using ten years of Oklahoma crash data obtained from the Fatality Analysis and Reporting System (FARS), Highway Performance Monitoring System (HPMS) and the Oklahoma Pavement Management System (PMS) databases to investigate the impact and significance of various roadway factors in Oklahoma crashes. Lastly, Analytic Hierarchy Process (AHP) was employed to rank roadway variables in order of their importance to roadway safety by assigning weights to them. It is anticipated that this research will assist Oklahoma Department of Transportation (ODOT) in evaluating future use of tools for assisting safety management efforts in Oklahoma and also to collect and store data for the roadway elements that have significant impact on Oklahoma crash rates.