Date of Award
Master of Architectural Engineering (MAE)
Dr Rrad Sariji
Dr. Stephen Treado
Dr. Rashed AI Shaaly
One of the important factors in striving towards sustainable urban living is the safety of pedestrians. This safety is influence by many factors, one of which is the ability of drivers to see pedestrians. During the night, pedestrian visibility becomes more difficult, especially on two-way streets, where headlamps of cars from the opposite direction cause glare to drivers. Newer types of headlamps are using LEDs and Xenon which are glarier than older halogen types.
This study is arranged in two parts. The first part of which examines the effect of oncoming car headlamps on pedestrian night time visibility. Detection distance was used as a measure of visibility. The detection distance was measured in the presence and in the absence of on-coming car headlamps in an unlit street. Pedestrians wore three different clothing colors; white, yellow and, black. It was found that, for pedestrians wearing white and yellow clothing, the detection distance was reduced by half in the presence of on-coming car headlamps compared to the detection distance when on-coming headlamps were absent. The mean detection distance dropped by 60% for pedestrian wearing black clothing.
The other part of this study examines the effect of different types of street lights which are: HPS, MH and LED Street lights on pedestrian night time visibility. The detection distance was measured in the presence of on-coming car headlamps. Pedestrians wore three different clothing color: white, yellow and black. It was found that, statistically MH and LED street lights had the same mean detection distance which was larger than HPS. In relation to the cloth colors, we found that the white and yellow colors had a significant difference from the black color which means that the driver has some difficulties to designate the pedestrians who wear dark cloth colors. The finding of this study may influence speed limit considerations as well as street lighting design standards.
Younis, Dana, "Comparative Pedestrian Visibility under Solid State Led Sources" (2013). Theses. 297.