Electroluminescent Materials Can Further Enhance the Nighttime Conspicuity of Pedestrians Wearing Retroreflective Materials.

OBJECTIVE: We investigated the nighttime conspicuity benefits of adding electroluminescent (EL) panels to pedestrian clothing that contains retroreflective elements. BACKGROUND: Researchers have repeatedly documented that pedestrians are too often not sufficiently conspicuous to drivers at night and that retroreflective materials can enhance the conspicuity of pedestrians. However, because retroreflective elements in clothing are effective only when they are illuminated by the headlamps of an approaching driver, they are not useful for pedestrians who are positioned outside the beam pattern of an approaching vehicle's headlamps. Electroluminescent materials-flexible luminous panels that can be attached to clothing-have the potential to be well suited for these conditions. METHOD: Using an open-road course at night, we compared the distances at which observers responded to pedestrians who were positioned at one of three lateral positions (relative to the vehicle's path) wearing one of two high-visibility garments. RESULTS: The garment that included both EL and retroreflective materials yielded longer response distances than the retroreflective-only garment. This effect was particularly strong when the test pedestrian was positioned farthest outside of the area illuminated by headlamps. CONCLUSION: These findings suggest that EL materials can further enhance the conspicuity of pedestrians who are wearing retroreflective materials. APPLICATION: EL materials can be applied to garments. They may be especially valuable to enhance the conspicuity of roadway workers, emergency responders, and traffic control officers.

Drivers' judgments of the effect of headlight glare on their ability to see pedestrians at night.

INTRODUCTION: Several studies have concluded that pedestrians typically overestimate their own conspicuity to approaching drivers at night. The present experiments extended this research by exploring the accuracy of drivers' judgments of pedestrian conspicuity while facing varying degrees of headlight glare. METHOD: In Experiment 1, participants on an open road estimated their ability to see a roadside pedestrian in each of two clothing configurations and with each of three different glare intensities present. In Experiment 2, participants responded to a roadside pedestrian under the same open road conditions; the participants were naïve with regard to both the position of the pedestrian and to the clothing and glare manipulations. RESULTS: Consistent with earlier research, estimates of response distance were, on the average, over three times greater than actual recognition distance. The extent to which participants overestimated conspicuity was greater when the pedestrian wore a retroreflective vest, and participants incorrectly judged that headlight glare would not degrade drivers' ability to see a pedestrian wearing a retroreflective vest. CONCLUSIONS AND PRACTICAL APPLICATIONS: These results confirm that road users' understanding of issues involving drivers' night vision is limited. These misunderstandings may result in road users behaving in ways that increase the risk of nighttime collisions with pedestrians.

The accuracy of drivers' judgments of the effects of headlight glare on their own visual acuity.

Drivers' judgments of the magnitude of disability glare caused by high-beam headlights may not match actual declines in visual performance. This study investigated younger and older drivers' beliefs about their own visual performance in the presence of headlight glare. Eleven older drivers and seventeen younger drivers judged the distance at which they would just be able to recognize the orientation of a white Landolt C if it were present adjacent to the headlamps of a stationary opposing vehicle at night. The younger participants were generally accurate in their estimates of the recognition distance of the stimulus, while older participants significantly overestimated both their own acuity and the effect of glare on their vision. From this study, we see that older drivers' judgments about the disabling effects of oncoming headlights may be systematically inaccurate. These misperceptions about headlight glare may help explain why drivers tend to underuse high beams.