What is a rumble line?

Rumble strips, also known as sleeper lines, audible lines, “the corduroy”, growlers, and “woo woo” boards, are a road safety feature to alert inattentive drivers of potential danger, by causing a tactile vibration and audible rumbling transmitted through the wheels into the vehicle interior.

Are rumble strips effective?

Center line rumble strips are an effective countermeasure to reduce head-on collisions and opposite-direction sideswipes (often referred to as cross-over or cross- center line crashes). Center line rumble strips are primarily used to warn drivers whose vehicles are crossing center lines of two-lane, two-way roads.

What is a rumble used for?

The driver of a vehicle passing over a rumble strip hears an audible warning (rumbling sound) and feels a vibration. These physical and audible warnings alert the drowsy, distracted or impaired driver, thus reducing the chance for a crash.

What are the bumps on the freeway called?

Speed humps, sometimes called road humps or undulations, are used for 10–15 mph speed zones. They’re often seen on local streets or connector roads where traffic needs to flow smoothly but excessive speed will endanger pedestrians.

Who invented rumble strips?

Inattentive or sleepy drivers automatically became more alert once their car tires came into contact with the rumble strip, producing an unmistakable rumbling sound. ÅF Lighting’s invention of the rumble strip is now spreading all over Europe, creating safer motorways along the way.

What are mumble strips?

What are mumble strips? Sinusoidal rumble strips are also called mumble strips. They are similar to traditional rumble strips, but mumble strips have a wave pattern ground into the pavement that lessens the external noise produced when vehicles travel across them. Traditional rumble strips do not have the wave pattern.

Where are rumble strips used?

Centerline rumble strips are used on undivided highways to reduce cross-over incidents and resultant head-on collisions. Shoulder rumble strips are used primarily to reduce run-off-road collisions. They alert distracted or drowsy drivers that they are leaving the roadway or crossing the centerline of the road.

What are the grooves on the side of the highway called?

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.

Why are there rumble strips in the middle of the road?

Rumble strips are raised or indented patterns installed to alert drowsy or inattentive drivers to the fact that they are drifting out of their lane. On two-lane, two-way highways rumble strips are often installed on the centerline to keep drivers from drifting into oncoming vehicles, causing a cross-over crash.

Which rumble strips make the most noise?

Milled rumble strips are considered the most audible and provide the most vibration. Rolled rumble strips are made of V-shaped or rounded grooves that are pressed into hot asphalt during construction.