Weights from a Safety Perspective for Interchange Lighting Prioritization

The focus of this paper is to research and update weights (values indicating the effect) to multiply ratings of selected factors used in the Total Design Process (TDP) for interchange lighting prioritization from a safety perspective. Results based on analysis using data collected at 80 interchanges along nine segments in North Carolina showed differences in weights for currently used factors such as freeway median width, freeway number of lanes and night-time traffic volume per lane. Results also showed that considering the number of night-time crashes by severity instead of night-to-day crash rate ratio, for prioritization of interchange lighting system installation or maintenance, would reduce the bias towards interchanges with fewer numbers of crashes and lead to better utilization of limited available transportation funds.