Safety cameras

Safety cameras are an important element in the Safer Essex Roads Partnership’s (SERP) road safety strategy.

There are more than 100 permanent speed camera installations and 28 red-light camera installations across the SERP area. The strategy also incorporates the use of handheld devices, which allows for dynamic speed enforcement throughout the area at locations where the provision of a permanent installation is not justified.

All enforcement cameras are highly technical pieces of equipment, and, to explain how they operate in detail, would require a highly technical description. However, in this section, it is explained, in simple terms, how each camera type works.

All cameras used for enforcement purposes have to be Home Office Type Approved.  This guarantees the integrity of the equipment and ensures that the information recorded by the camera is accurate when used in accordance with the manufacturer’s instructions.  All permanent camera installations in Essex are digitally enabled and send information directly to the processing centre.  Security and encryption measures are integral to the systems to ensure the digital evidence cannot be hacked or tampered with.

Many challenges to the accuracy of cameras have been raised over the years, but the level of testing required under the Home Office Type Approval process, and the practice of having all cameras calibrated annually, ensures their accuracy is maintained. Cameras are never used for enforcement without a valid calibration certificate.

All permanent camera systems are supported by traffic signing which advises motorists of the presence of the enforcement devices and for speed camera systems, the speed limit being enforced.

Camera types used in the SERP’s area


Permanent Speed Camera Installations

These are the single stand-alone installations for which the housings are painted yellow and usually located on the left-hand side of a road. These installations are normally provided on roads where there has been a number of fatal or serious collisions over a set period, and evidence showed that a high proportion of vehicles were exceeding the speed limit. The majority of cameras in the SERP area were introduced as part of the Department for Transport’s Safety Camera Programme between 2000 and 2007.  This type of installation only records the speed of a vehicle at a particular point or spot on the road and are commonly referred to as spot-speed cameras.


Permanent Average Speed Camera Installations

Average speed cameras are able to cover a long stretch of road by having cameras located at variable distances.  The cameras record the speed of vehicles and calculates the average speed for each vehicle over the length of road concerned.  The average speed system is particularly suitable for dual carriageway situations where there are usually fewer junctions.  These cameras are normally mounted above the road and are also highlighted in yellow.  Average speed cameras encourage motorists to maintain a safe speed over a long length of road, rather than at a specific location. As with permanent speed camera installations, average speed cameras are placed on roads where there has been a history of fatal and serious collisions.


Permanent Managed Motorway Camera Systems

Managed Motorway Cameras have been introduced by Highways England on the M25 in Essex. They are permanent speed camera installations located at the side of, or above the motorway; these cameras support a variable speed limit for which signs are mounted on gantries across the motorway.

This system varies from the other types of permanent fixed camera systems in two key areas: first, they are not always painted yellow (it should be noted there is no legal requirement for any camera to be painted yellow); and they are able to record an image of the speed limit displayed on the associated gantry at the time of an offence.  Motorways comprise two or more lanes of traffic and these cameras are particularly sophisticated in that they can capture the speed of a particular vehicle across many lanes of traffic.

hand-held-cameraMobile Hand-held Speed Cameras

SERP uses ‘Trucam’ speed measuring devices which, although hand held, are able to store video evidence of a vehicle, and records all the necessary information for the vehicle being monitored.  Other forms of hand held speed measuring devices are used by the SERP but these do not capture images of speed offences and require vehicles to be stopped at the road side.

red-light-camera2Permanent Red-light Camera Installations

These camera installations are single stand-alone units that are located on one or more approaches at a traffic signal controlled junction.

The camera housings are painted yellow for added conspicuity and have been installed at locations where there has been a history of personal injury collisions involving at least one driver or rider that has disobeyed a red traffic signal.

The majority of red-light enforcement cameras in the SERP area were installed during the Department for Transport’s Safety Camera Programme that took place between 2000 and 2007.

How do enforcement cameras work?

Speed cameras operate in different ways – here is a simple guide as to how they work.

Permanent Speed Camera Installations
Permanent speed cameras used in the SERP area utilise a ‘passive radar system’; a radar signal is constantly sent out from the camera housing and if a vehicle goes by, the radar signal is bounced back to the camera, and when this happens, the camera is able to calculate the speed of the vehicle.

When a signal is bounced back above a pre-determined threshold speed, which is above the speed limit of the road, the camera takes two photographs.

Permanent Average Speed Camera Systems
Average speed cameras use the simple theory that a vehicle covering a set distance, in a set time, will be travelling at an average speed over that distance. A camera is located at the beginning of a stretch of the road being enforced, with a second camera located at the end of the stretch.

The cameras use a combination of infra-red and normal digital photography. The first camera records the number plates of all of the vehicles entering the enforcement area and the second camera at the end of the enforcement zone records the number plates of all vehicles as they exit the stretch of road being enforced.

The system checks all vehicles and the time it has taken for them to travel the distance between the cameras.

If the average speed is above the threshold, the camera takes a photograph of the vehicle in question.

Mobile Hand-held Speed Cameras
The hand-held cameras used by SERP use a laser to check the speed of a vehicle. When an operator sees a vehicle approaching, they first assess whether, in their view, the vehicle appears to be travelling above the set speed limit. If they believe this to be the case, they aim the hand held camera at the vehicle, and when the vehicle is aligned in the target area shown on the camera screen, the operator presses the trigger.

A series of beams are fired at the vehicle which reflect back to the camera, and the time difference between the beams being sent out and returned gives the speed of the vehicle.

The hand-held cameras used by SERP also record a continuous video image which provides evidence of the offending vehicle.

Other hand-held cameras used by the SERP operate in a similar way but are not capable of storing a moving image of an offence. In these cases the officer will physically stop the vehicle and take the driver or rider’s details which will be used to determine the appropriate course of action.

Permanent Managed Motorway Camera Systems
These operate in a similar way to permanent camera systems in that they are also radar-based, but unlike permanent installations, the managed motorway system is supported by a variable speed limit.


Q: I’d like a speed camera installed in my road. How do I go about requesting one?

A: If you have a concern about the safety of a road, the best way to take your concerns forward is to contact your local County Member (councillor) in the first instance. They can then consider the issue and your request and bring it to their Local Highway Panel for consideration as a potential future scheme.