Shoulder and centerline rumble strips have become predominantly used safety measures along American highways in almost all states and in Canadian provinces. Milled shoulder rumble strips are cut indentations along the shoulder of a highway to warn drivers with an audible and tactile alert if they start drifting off the road. Centerline rumble strips are similar, but are placed between lanes, usually on undivided two-way, two-lane highways, to warn drivers who may start drifting into oncoming traffic. Researchers at Kansas State University (KSU) have conducted research on a new football-shaped highway rumble strip designed by an independent firm in Kansas. Test strips were installed along a Kansas highway, and the KSU research team conducted several tests to evaluate the new football shaped rumble strip versus the rectangular rumble strip. The comparison consisted of water and debris collection, interior sound and vibration production, and the opinions of bicyclists.Based on the literature review, the limited tests performed, and the surveys conducted, it can be concluded that no significant difference was found between the two types of rumble strips.
