Collisions between pedestrians and vehicles can occur at any point along a roadway and can be a result of pedestrian behaviour, driver behaviour, or both. A report of the Metropolitan Orlando Bicycle and Pedestrian Program notes that in an investigation of 617 pedestrian-vehicle crashes, 51.6 percent of this class of crashes happened at night with an even distribution between lighted roads and unlighted roads. However, for fatal crashes, 58.6 percent occurred at night on unlighted roads and 25.3 percent occurred at night on lighted roads. The primary cause of these crashes appeared to be the lack of visibility of pedestrians as they crossed the road. The purpose of this report is to provide information to traffic engineers and lighting designers regarding lighting parameters that impact the ability of drivers to see pedestrians in midblock crosswalks and to enable agencies to evaluate the potential effectiveness of lighting designs. While some visibility concepts are discussed below, this report does not cover all aspects of night-time visibility and the human visual system. The information is based on static and dynamic experiments performed at the Virginia Tech Transportation Institute and documented in FHWA-HRT-08-052, available at NTIS under publication number PB2008-106431. The initial static experiment used the time it took for an observer to detect the pedestrian or surrogate target as a metric for visibility, while the dynamic experiment used the distance at which pedestrians or surrogate targets were identified as the metric. Experimental condition variables included lamp type (high-pressure sodium, metal halide), vertical illuminance level (6, 10, 20, and 30 lx), colour of pedestrian clothing (white, black, and denim), position of the pedestrians and surrogates, and the presence of glare. (Author/publisher)
Samenvatting