Analysis of road safety in the context of horizontal visibility within intersections – field studies

One of the important factors on which road safety depends is adequate visibility. This article analyses horizontal visibility within road intersections. The visibility condition depends on many factors, primarily on the geometric parameters of road elements and the location of buildings, fences, vegetation etc., neighboring the road. The aim of the research presented in the study was to determine the current condition of horizontal visibility, on the example of twenty two intersections located mostly in built-up rural area along a provincial road near Czestochowa. The research was carried out by two methods (the analysis of satellite photographs and the visual method) and the obtained results were compared. The assessment of the security level was based on applicable regulations and technical guidelines. It was found that the results of the visibility assessment based only on the analysis of maps and satellite photographs are in many cases overestimated, due to the fact that many small elements not visible in the photographs are not taken into account and the occurrence of convex vertical road arches within the field of visibility. However, the main reason for the insufficient visibility at the many intersections is the fact that the geometrical parameters of roads and their surroundings were shaped in the past when the traffic conditions were completely different. It was also noted that road managers perceive this problem and take measures to increase safety within road intersections.