The effects of hydrophobic treatment of the driver-side window and rearview mirror on distance judgement

Abstract

This study investigated the effects of hydrophobic treatment on distance estimation under conditions of simulated rain and wind when applied to the driver-side window and driver-side exterior rearview mirror. The dependent measure was the estimate of distance to a target vehicle viewed through the driver-side window and rearview mirror. The following independent variables were examined: actual distance, hydrophobic treatment of the driver-side window, hydrophobic treatment of the driver-side exterior rearview mirror, participant age, and participant sex. While the results of this study indicate no significant effect of hydrophobically treating driver-side windows or mirrors, one marginally nonsignificant interaction of interest was observed. Specifically, there was a tendency for older drivers to report shorter (more conservative and presumably safer) distance estimates when viewing vehicles through a driverside window that has received hydrophobic treatment. This tendency, in combination with over-representation of older drivers in lane change/merge crashes, suggests that additional research efforts should be focused on examining the potential for safety benefits from applying hydrophobic treatment to driver-side windows.