Evaluation of Driver Perception–Reaction Time under Rainy or Wet Roadway Conditions at Onset of Yellow Indication

Abstract

The research presented in this paper characterizes the impact of a wet pavement surface and rainy weather conditions on driver perception–reaction time (PRT) at the onset of the yellow indication on the approach to a high-speed signalized intersection. An in-vehicle differential Global Positioning System was used in a controlled field environment. Three hundred eighty-four data records for all drivers who stopped at the onset of the yellow indication were available for analysis. The minimum time to intersection (TTI) ranged from 2.35 s to 5.71 s. Statistical analyses were used to quantify the effects of the TTI, grade (uphill or downhill), gender, and age (<40 years, 40 to 59 years, and ≥60 years) on driver PRT. The study demonstrated that driver PRT increases as TTI increases. A longer PRT was found when vehicles traveled along an upgrade section, given that the driver was typically accelerating when the yellow indication was initiated. No gender differences were found in PRT, and no statistically significant differences were found between different age groups. Furthermore, the study demonstrated that driver PRT increased under conditions of a wet pavement surface and rainy weather as compared with clear weather conditions over the entire TTI range.