On-Road Measures of the Nighttime Conspicuity of Pedestrians

Abstract

Pedestrian fatalities, which in the U.S. account for 12% of all traffic fatalities, are more common at night. This experiment quantified drivers' ability to recognize the presence of pedestrians at night. Ten younger and ten older participants drove around a closed road circuit and indicated when they first recognized that a pedestrian was present. The percentage of pedestrians recognized was recorded and a parallax-based video system measured recognition distances. Results confirm that a severe pedestrian conspicuity problem exists and that driver age, clothing configuration, headlamp beam setting, and glare all significantly affect pedestrian recognition. In the most challenging condition (low beams, black clothing, glare) only 5% of pedestrians were recognized. At the other extreme, 100% of the pedestrians were recognized when they wore retro-reflective materials depicting biological motion (without glare present). Without glare, mean recognition distances varied from 0.0 meters (older drivers, low beam, black clothing) to 220 meters (younger drivers, high beam, biomotion).

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