Evaluation of Low-Cost Intersection Countermeasures to Reduce Red-Light-Running Violations: Retro-Reflective Signal Back Plates

015446632013Final ReportPDFTech ReportMATC-KU: 16525-1121-0003-165Traffic accidentsRed light runningReflective signsRetroreflectorsSignalized intersectionsCountermeasuresAccident causesBefore and after studiesCase studiesDriversAgeGenderPeriods of the dayResearch HubHighwaysOperations and Traffic ManagementSafety and Human FactorsI83: Accidents and the Human FactorI85: Safety Devices used in Transport InfrastructureRetroreflectorsSignalized intersectionsTraffic crashesUnited StatesMid-America Transportation CenterDissanayake, SunandaDias, IshaniKansas State UniversityUnited States. Dept. of Transportation. Research and Innovative Technology AdministrationUS Transportation CollectionRed light running has become a serious safety issue at signalized intersections throughout the United States. One objective of this study was to identify the characteristics of red-light-running (RLR) crashes and the drivers involved in those crashes. Driver characteristics, time and day of the crash, occupancy of the vehicle, and environmental factors were tested against any relationship with the RLR crashes and other signalized intersection (non-RLR) crashes. The other objective was to evaluate the effectiveness of retro-reflective signal backplates in reducing red light running as a low cost countermeasure. Crashes that happened in the State of Kansas were analyzed as a case study. Contingency table analysis was used to identify whether a particular factor is related to the crash type, i.e. RLR vs non-ROR. Two methods were used to evaluate the effectiveness of reflective backplates: cross-sectional analysis using an intersection with reflective backplates and an intersection without reflective backplates, and a before-and-after study using four intersections. According to the results of contingency table analysis, the driver age and safety equipment usage, injury severity of the driver, crash severity, time and day of crash, adverse weather conditions, and surface condition were related to crash type. Variables such as gender of the driver, light condition, and presence of passengers were not related to the crash type. The cross-sectional analysis found that reflective backplates are effective in reducing red light violations in the through and left turning traffic flows. The before-and-after study showed a significant reduction in red light violations in one of the two treatment sites, according to paired-t-test statistics. The reduction of red light violations was not significant in the other. Both analyses could not prove a significant impact on red light violations among the right turning vehicles