More than every fourth driver killed in traffic collides with a fixed obstacle at the roadside. Half these fatalities occur when hitting a tree, with about 50 fatal accidents annually or almost as many as the number of cyclists killed during one year. Annually, slightly more than 20 fatal accidents in collisions with guardrails; about 10 fatal accidents in collisions with lamp posts and slightly more than 10 fatal accidents in collisions with other types of posts. The highest risks of accidents with posts occur on the municipal road network. This is natural since most posts are concentrated to this road network. Half the number of hit posts in the road environment are lamp posts and they are often placed within a couple of metres from the roadside. Concerning the traffic safety problem of lamp posts, the distance from the road is not decisive but rather the size of the posts. Their position at the side or in the middle of the road is decisive and it is important whether the post is rigid or deformable when hit. The worst position regarding traffic safety is that of lamp posts placed on the outside of curves, which results both in increased risks of collisions and more severe injury consequences. Lamp posts placed on the inside of curves are in the safest position of all. Lamp posts in the middle of the road in the central reserve or on traffic islands at junctions have lower personal injury accident risk than lamp posts placed on the roadside. The result of the study generally shows that lamp posts must not be placed on the outside of curves. Furthermore, rigid steel posts should gradually be exchanged for deformable and energy absorbing posts, which should be used when installing new road lighting. There are also possibilities of reducing the number of lamp posts in the road environment without any impairment of lighting, by replacing posts by high lattice towers at junctions and roundabouts or by using wire suspended lighting in the street environment. It is important to point out that road lighting saves about 35-40 lives annually despite the above-mentioned inconveniences, which can and should be reduced. (A)
Samenvatting