Single-vehicle run-off-road crashes represent a large share of accidents in the U.S. The category is large in part because it covers such a broad range of roadway departures. Included are intentional departures to avoid other vehicles or objects; involuntary departures due to tire blowout, ice, hydroplaning, or trailer sway; and driver error from distractions or drowsiness. Within this category is a much smaller, more lethal crash type, known as drift-off-road crashes, caused by drivers who drift off the road due to drowsiness, inattention, or distraction, and are responsible for a disproportionate share of severe run-off-road crashes. This article discusses findings from a Michigan study indicating that rumble strip design and placement can significantly reduce the incidence of drift-off-the-road crashes.
Abstract