Mobile speed enforcement safety patrols are operated by West Yorkshire Police on behalf of West Yorkshire Casualty Reduction Partnership and operate in known casualty zones. Patrols are sited according to how many lives they might save and injuries they might prevent.

Mobile cameras may only be deployed on a site length of between 0.4 and 5 km where there has been at least 1 collision causing death or serious injury per km within the previous 3 years. In addition, there must have been a high number of other injury-causing collisions.

At least 20% of drivers must be exceeding the speed limit at the location. "Speeding" is defined as at least 10% above the speed limit plus 2mph (e.g. 35mph in a 30mph zone) for free-flowing traffic excluding any rush hour periods.

In addition, cameras may only be used where it can be shown that other highways improvement and road safety measures have been tried but have failed significantly to reduce the numbers of crashes and casualties.

If you see a mobile patrol, you are in a casualty danger zone!

There are clear Government requirements covering where and how mobile safety cameras should be placed, and the measures to be taken to ensure drivers are aware of them. The Partnership identifies each mobile patrol location along with the local highways authority, and once approval for the site is given, the area is surveyed for the best parking spot to deal with the problem. Locations are selected with the full knowledge and approval of the Assistant Chief Constable of West Yorkshire Police.

The patrol vehicles use leading-edge, laser speed measurement technology. It is a stationary laser, not hand held, that pinpoints a specific vehicle. The laser emits a series of invisible light pulses to measure both the range and speed of vehicles. It is invisible to radar detectors. It is used at an operational distance up to 2,000ft. The equipment is calibrated annually and check procedures are completed by the operators prior to each use.

The laser operates effectively in a wide range of weather and light conditions, enabling the roadside patrols to enforce throughout the year. Specially-trained police officers, employed by West Yorkshire Casualty Reduction Partnership, wear full police uniform and wear high visibility jackets while on duty.

Mobile patrols must be highly visible. They do not operate covertly and the Government has laid down the guidelines on the visibility of mobile patrols.

West Yorkshire Casualty Reduction Partnership uses police-liveried Ford Galaxies and a police-liveried police motorcycle. In addition to clear police markings, all vehicles are identified as belonging to West Yorkshire Casualty Reduction Partnership. Patrol vehicles are positioned so as to be clearly highly visible to approaching motorists in order to encourage them to check that they are driving within the legal limit.

Location details of where mobile patrols are operating this week and next in West Yorkshire are available within Future Patrols.

The installation of safety cameras is only one aspect of casualty reduction. We are always looking for the most effective measure in any situation and safety cameras are a last resort.