Consideration of Driver Behavior in the Design of Red Light Extension Systems

Graduation date: 2016Red Light Running (RLR) is a safety hazard at signalized intersections in Oregon and throughout the United States. Various methods of mitigating factors contributing to RLR have been implemented but few protect against a conflict when a vehicles runs a red light. Additionally, current prediction algorithms are complicated; there is a need for a simplified method which uses input values that are easily measured at an intersection.\ud This study investigated current RLR countermeasures, specifically red clearance extension systems which extend the red clearance interval when a RLR vehicle is detected with the goal of reducing RLR crashes. A field study was completed which investigated driver behavior at five intersections in Oregon in regards to the development of a red clearance extension system. Specifically, driver behavior in response to the yellow and red indications on the major approach, and the green indication on the minor approach were observed using 149 hours of transcribed video data. Analysis determined RLR rates ranging from 0 to 1.263 RLR vehicles/hour and 5th %ile time to conflict (TTC) times ranging from 2 to 4s. These factors, which are simple to determine, are then used to develop an equation which calculates a red extension time input for a red clearance extension system