c-tedd@uta.edu +1 817 272 5138

This Webinar on Creative Utilization of Urban Roadway Facilities with Predictive Safety Assessment Tool – Phase 1. is hosted by Dr. Mouyid Islam of the University of South Florida, covers his team's work with a novel tool that can help improve safety on our roadways.


The impact of predictive safety assessment based on quantitative methodology of the Highway Safety Manual (HSM) is significant, particularly in urban roadway facilities. Realizing this significance, the responsibilities of safety professionals, transportation planners, and decisionmakers are critical for safe and efficient transportation in the ever-increasing travel demand in the urban areas. The purpose of this project was to develop a predictive safety assessment tool (PSAT) for converting one urban roadway facility type to another with the application of predictive methodology and principles in the HSM. This tool (PSAT) is intended to help safety professionals, transportation planners, and decisionmakers to evaluate safety effects considering the local conditions to make informed decisions in the planning process from the traffic safety perspective. This project focused on developing a proof-of-concept framework of PSAT for converting one facility to another with improvements to specific geometric elements in urban settings. By considering traffic exposure, existing geometric conditions, and unit length of corridor (i.e., one mile of corridor length), PSAT (MS Excel spreadsheet) enables the safety analysts to evaluate existing and proposed facilities and covers a wide range of urban roadway segments, including 2-lane undivided roadway; 2‑lane roadway with two-way left-turn lane; 4-lane undivided and 4-lane divided roadway; 4-lane undivided roadway with two-way left-turn lane, 6-lane undivided lane, and 6-lane divided roadway; 6-lane undivided roadway with two left-turn lanes; and 8-lane divided roadway. The PSAT was developed with user-friendliness to help the safety analysts input values in color-coded areas within the recommend ranges for the parameters from the HSM. The output of the crash prediction and sensitivity analysis (i.e., impact of traffic volume on predicted crashes in comparison facilities of interest) were graphically displayed. Thus, PSAT displays a user-friendly dashboard for the safety analysts with a conversion factor and predicted crash frequency, distribution of collision types (i.e., single- and multi-vehicle collisions) by injury severity levels and impact of traffic volume as part of a sensitivity analysis based on the well-researched HSM methodology.

Lear more about the project here