Speed limits
Setting speed limits
For speed limits to be effective they must be set at a level that appears reasonable to a driver and adequately reflect the environment through which the road passes.
Many people consider speed limits as the answer to all road safety concerns and whilst appropriately set speed limits can improve road safety, erecting speed limit signs does not always produce the desired level of vehicle speeds unless a driver can see a need for the limit.
Our policy on setting Local Speed Limits (PS05/02) is based on the national guidance provided by the Department for Transport. A link to the national guidance is provided below.
We consider many factors when determining the appropriate speed limit. The predominant factors that are considered are:
- Road environment and characteristics of the road
- Average speed of the traffic
- Number of vulnerable road users
The speed limit assessment is carried out over a minimum distance of 600-metres.
While outside of the main policy criteria, the number of personal injury crashes, types of speed reducing measures required, buildings like schools and hospitals, and community concern are also considered.
Changes to speed limits
Average traffic speeds are used to determine the most appropriate speed limit for a road, as the mean speed reflects the speed that most drivers consider to be the safe speed for the road environment.
Introducing speed limits that are too far below the existing mean speed of drivers is not effective. If a limit is set too low for the road environment drivers will continue to travel at higher speeds.
An experienced officer carries out site visits to assess requests against the national guidance and our speed limit policy.
The Police are responsible for enforcing speed limits and we always consult with them to ensure we have their support before taking a new speed limit forward. We must ensure that, as far as possible, speed limits are self-enforcing and will not be solely reliant on continuous enforcement to be effective.
National speed limits
There are three national speed limits
- 30mph on roads with street lighting (sometimes known as restricted roads)
- 60mph national speed limit on single carriageway roads
- 70mph national speed limit on dual carriageways and motorways
These speed limits are not appropriate for all roads. Where the road environment suggests another speed limit is appropriate, the County Council can progress a Traffic Regulation Order (TRO) to introduce a different speed limit. The permitted speed limits are 20mph, 30mph, 40mph, 50mph or 60mph speed limit.
It takes several months to complete a TRO as we have to carryout consultations and follow a statutory procedure before the traffic signs can be introduced.
Requests for a lower speed limit should be submitted to the Road Safety Team providing as much detail as possible, including the current speed limit, what you believe the speed limit should be, and why you feel the change is needed.