Effectiveness of Rumble Strips Positioned at Different Lateral Distances to the Edge Line to Avoid Run-Off-Road Accidents

Epidemiological studies have shown that the share of single vehicle run-off-road accidents caused by inattention, distraction and drowsiness ranges between 20% up to 60%. One measure to avoid these accidents is the installation of rumble strips at or close to the edge line of the hard shoulder. Even though one percent of vehicles drive on the hard shoulder and thus pass the edge line without the drivers being inattentive, distracted or drowsy. Hence the installation of rumble strips would result in unnecessary noise pollution to the people living close to the road.
This study shows at which position to the edge line rumble strips could be installed at the hard shoulder to avoid unnecessary noise pollution and still potentially reduce run-off-road accidents. The analysis of real accidents showed an effectiveness reducing run-off-road accidents with rumble strips of approximately 41% if rumble strips are positioned directly on the edge line. The effectiveness of rumble strips is not influenced much by varying the distance of up to 0.5 m to the edge line. Still approximately 37% of run-off-road accidents might be avoided.