Electroluminescent Materials Can Improve Nighttime Pedestrian Conspicuity When Added to Retroreflective Garments

Abstract

Retroreflective materials make nighttime pedestrians more conspicuous to drivers, especially when configured in a biological motion pattern. Because retroreflectors are only effective when they are illuminated by a light source near the driver, they are not useful for pedestrians who are positioned outside the beam of a vehicle’s headlamps. Electroluminescent materials have the potential to enhance conspicuity in these conditions. We investigated the conspicuity benefits of adding electroluminescent material to clothing containing retroreflectors. We compared, using an open-road course at night, the distances at which 120 observers responded to a test pedestrian wearing one of two garments at one of three roadside locations. Response distances to the garment that contained both electroluminescent and retroreflective materials were significantly longer, particularly when the pedestrian was more poorly illuminated as a result of being positioned on the left shoulder. These findings suggest electroluminescent materials have the potential to enhance the conspicuity of pedestrians.