In his letter "Ring road rumbles" (March 16 ), Mr Herbert questions the recent addition of rumble strips on the approaches to three roundabouts on the Outer Ring Road (A1237).

The measures have been introduced as part of City of York Council's Local Safety Scheme programme in response to a clear pattern of collisions which have resulted in 16 people being injured during a three-year period.

They all involved vehicles on the A1237 approaching roundabouts at speed and not slowing down in time to avoid a collision with a vehicle in front.

The rumble strips provide an audible warning to encourage drivers to slow down early enough to avoid late braking which could lead to such collisions.

Areas of anti-skid surfacing have also been provided to help drivers stop safely if they need to brake sharply.

The rumble strips have been laid at a height of only around 10mm and are designed to create an audible warning without causing significant discomfort for those in vehicles.

Rumble devices, in a variety of forms, have been widely used nationally since the early 90s to help alert drivers to hazards ahead.

As far as we are aware, the use of rumble strips in York and elsewhere has not been an issue that has caused concern to the ambulance service or other emergency services.

Indeed, police support the new measures based on their potential to reduce the number of collisions and injuries occurring.

We shall be monitoring the effect of these strips and requesting feedback from the emergency services as part of this process.

Ray Chaplin,

Head of Engineering Consultancy,

City of York Council,

Back Swinegate,

York.

Updated: 09:37 Tuesday, March 22, 2005