A Method to Calibrate Roadway Lighting Warrants and Levels with Crash History

Roadway lighting lacks a connection to the crash history. This book presents a novel method to calibrate lighting warrants and to identify effective levels of lighting in order to reduce the severity and frequency of night-time collisions. This new method uses an evidence-based mechanism to connect lighting-warrants with statistical analysis of collisions in order to adjust the scores of the grid system. It also connects the estimation of lighting levels with evidence-based statistical analysis of crash-history in order to identify recommended levels of luminance, illuminance and uniformity variations. The method expands the industry standards by providing the decision maker with two alternate non-exclusive approaches supported over collisions' frequency and severity criteria. A case study for highways in Quebec was used to calibrate the warrants and identified recommended levels of luminance, maximum uniformities of illuminance and of luminance. A case study of Arthabaska municipality illustrates the application at a small region. Calibrated warrants will be based on significant variables and available data and adjusted design levels will become effective minimums to safe lives.