The aim of this study was to evaluate the crash effects of 87 signed fixed digital speed and red light (FDSRL) cameras and accompanying warning signs placed at 77 signalised intersections across Victoria. Fixed Speed cameras have been shown to be generally effective at decreasing crash rates whilst the effectiveness of Red Light Cameras (RLCs) to reduce crashes has been studied on many occasions with mixed results. The use of combination speed and red light fixed camera enforcement is relatively uncommon and has not been previously evaluated. Data were analysed using a before-after quasi-experimental design incorporating controls and Poisson regression to calculate the adjusted percentage reduction in the number of casualty crashes at treated sites in the post-treatment period when compared with the pre-treatment period. Analysis results estimated large decreases in casualty crashes associated with the FDSRL cameras and their associated signage. When only the crashes involving vehicles travelling form the approach intersection leg where the camera was placed are considered, the estimated casualty crash reduction was 47% (95% CI:(36, 56), p<0.0001). When crashes involving vehicles from all approaches are compared, the estimated casualty crash reduction was 26% (95% CI:(16, 35), p<0.0001). A 44% reduction (95% CI:(31, 64), p<0.0001) in right angle and right turn against crashes, those particularly targeted by red light enforcement, was also estimated. Whilst use of the FDSRL cameras was associated with a reduction in overall casualty crash risk, there was no evidence for a reduction in relative crash severity meaning the cameras were associated with equal reductions in minor injury crashes as serious injury and fatal crashes. Across the 77 intersection where the cameras evaluated were installed, it was estimated that 17 serious or fatal crashes per year and 36 minor injury crashes would be prevented representing crash cost savings to the community of over $8M. Based on the outcomes of the evaluation, continued and expanded use of combined fixed red-light and speed cameras in Victoria is expected to improve driver safety, save lives and reduce crash related costs. (Author/publisher) This project was funded through the Centre’s Baseline Research Program for which grants have been received from: Department of Justice Roads Corporation (VicRoads), Transport Accident Commission.
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