Safer Verges – Part 1: Use of Rumble Strips

This report concludes that road safety could be significantly improved if the UK adopted rumble strips on single carriageways.Rumble strips alert inattentive drivers of potential danger by changing the noise a vehicle’s tyres make on the surface.

While rumble strips in the UK are placed primarily on the edge of dual carriageways, in other countries they are also placed on the edge as well as the centre line of single carriageways

This report by TRL highlights the benefits of installing rumble strips along single carriageway roads to mitigate run-off-road (RoR) accidents.

TRL says research from across the world confirms the beneficial effect of rumble strips – describing them as ‘one of the highest benefit-to-cost roadside safety treatments’.

The study found ‘significant stretches of road’ where at least one death or serious injury a year per mile was likely to be avoided if rumble strips were deployed.

TRL says the findings present a good opportunity for Highways England to bring single carriageway sections of the strategic road network up to the same safety standard as the dual carriageway sections.

The report reads: “Effectiveness of rumble strip installation has been shown through a large number of research studies from around the world.

“Even though the predicted level of benefits can highly differ from one study to another, there is unanimity that the effect is beneficial (or at least is not adverse).”

The report also acknowledges the drawbacks of rumble strips – including the effects on cyclists and motorcyclists.

However, it says that new ‘innovative’ rumble strip patterns, such as those currently being used in America, could provide the answer to some of these issues, including noise.

It calls for a UK-based study be carried out to see the effects and benefits of modern rumble strip types.

The report says: “In contrast to its benefits, rumble strip installation may have some drawbacks which need to be considered during site selection and placement design.

“These concerns include the noise introduced into the road environment and the effect on other road users such as cyclists and motorcyclists.

“It is possible to mitigate these effects by using certain rumble strip designs, in addition to careful consideration during placement.”