A traffic calming device consisting of a raised ridge of asphalt, concrete, or rubber placed across a roadway to force drivers to slow down. They are typically 3 to 6 inches high and feature an aggressive slope, making them effective at reducing speeds to 15 mph or less in parking lots and residential zones. Highway designers contrast them with speed humps, which have a longer profile and allow slightly higher speeds.
The snowplow caught the edge of the rubber speed bump and tore it completely off the concrete anchors.
Traffic engineers strictly differentiate a bump (abrupt, for very low speeds) from a hump (gradual, for 20-25 mph zones).
Also heard as
- sleeping policeman
Related terms
Slow street
A residential roadway designed with physical traffic calming measures to restrict vehicle speeds.
Rumble strip
A series of raised or grooved patterns on a roadway edge designed to alert inattentive drivers.
Chicane
A series of alternating curves or lane shifts built into a roadway to slow down traffic.