Evaluation on Glare from Vehicle Lamps and Effectiveness of Road Components as Glare Barriers

Vehicle lamps are vital components which are required to ensure the driver’s safety, particularly at nighttime. However, vehicle lamps may cause glare which can reduce visibility and create discomfort. The objectives of this research are to evaluate glare from car headlamp and motorcycle lamps; and to study the effectiveness of road components on highway median, i.e. paddle, vegetation, and jersey barriers (87.5 and 122.5 cm high) as glare barriers. Luminance from headlamps and vertical illuminance on observer’s eye were measured to observe glare effect on vehicle drivers, expressed with the de Boer rating. The experiment results show that car headlamps observed at nighttime by car drivers in highway without barriers, scored 3~5 (disturbing~acceptable) on the de Boer scale; while motorcycle lamps in static position scored 1~3 (unbearable~disturbing). Paddle was found to be the most effective glare barrier in highway, for it might reduce glare up to scale 6 (acceptable).