What’s a rumble device designed to do?
A rumble device consists of raised markings or strips across the road, designed to give drivers an audible, visual and tactile warning. These devices are used in various locations, including in the line separating the hard shoulder and the left-hand lane on the motorway and on the approach to some hazards, to alert drivers to the need to slow down.
The then Department of Transport produced a leaflet which outlines the concept of Rumble Devices very well. Although it was produced in 1993 the concept is still the same today. It states:
Features with a vibratory and audible effect can be used, usually in rural areas, to alert drivers to take greater care in advance of a hazard such as a bend or junction. In combination with a gateway they can indicate the entry to a village or the start of a series of traffic calming measures. They have also been used to designate the start of shared use roads in new residential developments.