Rumble strips and stripes
What's the difference?
Rumble strips are grooves or rows of indents in the pavement designed to alert inattentive drivers through noise and vibration and reduce the number of accidents.
Rumble stripes are essentially rumble strips cut into the pavement where the white edge lines are placed. After the rumble strips are ground in, the white line is marked right over the rumble strips. The advantage is that the white line is much more visible in the rain and the rumble strip provides warning to a motorist who strays from the driving lane.
Where you'll find them
- Road shoulders - Shoulder rumble strips are longitudinal rumble strips installed outside of the edgeline (the yellow or white line that separates the travel lane from the left or right shoulder). The intent of shoulder rumble strips is to notify inattentive drivers that they are leaving the travelled lane - with the goal of reducing run-off-the-road crashes. They are also useful during snowy conditions to help the driver keep the vehicle in the travelled lane.
- Lane edges - Edgeline rumble stripes are installed to separate the travel lane from the shoulder.
- Centerlines - Centerline rumble stripes are installed to separate opposing traffic on undivided highways. The goal of these is to reduce head-on and opposite direction side-swipe crashes.
- Middle of the lane - Transverse roadway rumble strips are placed across the travelled lane to alert drivers approaching a change of roadway condition or a hazard that requires substantial speed reduction or other maneuvering.
Common factors for lane departure crashes
- Young drivers
- Fatigued and drowsy drivers (or “highway hypnosis”)
- Distracted driving such as texting and cell phone use
Roads and environment:
- Two-lane, undivided roads
- Rural, high speed roads
- Adverse weather conditions (rain, sleet, snow, fog, etc.)
- Curvy and hilly conditions