Evaluation of two Countdown Pedestrian Signal displays for pedestrian safety

摘要

The Manual on Uniform Traffic Control Devices (MUTCD) states that Countdown Pedestrian Signals (CPS) shall only be displayed during the clearance interval (FLASHING DON'T WALK - FDW) of pedestrian signals. The purpose of the CPS display is to inform pedestrians of the remaining time for crossing a road controlled by the signal, to discourage them from starting when there is insufficient time for complete crossing, and to inform those who are already on the way of the remaining time before the beginning of the DON'T WALK (DW) interval. The general literature on CPS is conclusive that CPS is better understood than the conventional pedestrian signals. In the District of Columbia the CPS display starts at the onset of the Steady WALK (SW) interval and continues through the FDW interval. It is not certain whether this CPS display has any advantage over the standard display as prescribed by the MUTCD. In this research a comparative field study of both types of countdown displays at twenty-five (25) intersections in the District of Columbia was conducted in addition to an attitudinal survey to gauge the public's preference of the type of display. The results of the evaluation showed that at the majority of the intersections studied, there were no statistically significant differences in pedestrian crossing behaviors (using 5% significance level) due to the type of CPS display. The attitudinal survey results showed that the majority of pedestrians (～86%) and drivers (～83%) prefer CPS display which starts at the onset of the SW.