More than 30 years have passed since Britain’s first-ever speed camera was installed on Twickenham bridge in London

The Gatso (short for Gatsometer) was the first fixed speed camera to gain official approval from the Home Office. Trials began in 1988, before they were pressed into use as enforcement devices from 1992. A Gatso camera uses radar to measure speed, then two static images of the passing vehicle for use when issuing a ticket.

Gatso speed cameras – officially called ‘safety cameras’ – were originally painted grey, but a change in the law stipulated that all cameras must be easily visible to drivers. In the early days, they also featured removable film, which had to be checked by operators. Digital versions that don’t rely on film arrived in 2007.

You’ll know if you’ve been caught by a Gatso, because a flash will illuminate the car and its number plate. Crucially, the photograph also captures the white calibration lines painted on the road.

Are road markings required?

There are two types of white lines – sometimes known as ‘dragon’s teeth’ – used for speed cameras. Some are painted in the centre of the lane, while others are found at the edges of the road. Some Gatso cameras have no road markings next to them, either because the camera housing is a dummy, or because the road has been resurfaced.

As this Freedom of Information (FOI) request highlights, ‘there is no laid down distance [for road markings] and [they] can vary by both area and site’.

If the speed camera is to be used within Section 20 of the Road Traffic Offenders Act, the lines or some other distance reference need to be present, so a secondary check can be carried out. The lines on the road are normally set at five feet, six feet, one metre or two metre intervals.

This is an important point, because Gatso speed cameras DO NOT require road markings for the speeding ticket to be enforceable. The lines are there to make it easier for safety camera partnerships to provide the necessary evidence. Using the lines is a more effective secondary check.

Alternatively, other fixed features can be used to assess the distance travelled by the vehicle between the two images in the evidence. An example could be the road markings in the centre of the road.

Slow down and stay safe

We contacted a road safety partnership for clarification. We were told: ‘If no lines are present an offence could still be prosecuted’.

The National Police Chiefs’ Council (NPCC) guide for the operational use of speed and red-light offence detection technology sheds more light on the subject.

Section 16.2.2 of the guide states: ‘HOTA [Home Office Type Approved] unattended automatic devices will have a second independent method of checking the primary speed measurement. One such method offered by manufacturers is the taking of two photographs of the offending vehicle at a known time apart, which can be compared with the distance travelled within that time interval to drive at the speed of the vehicle. Only approved methods of secondary checks should be utilised.’

No markings for average speed cameras

Modern speed cameras do not rely on road markings to catch speeding motorists. Take the SPECS digital cameras (pictured above), which measure the average speed between two cameras. These are commonly found on A-roads, or to enforce temporary speed limits on motorways.

The fact is, speed cameras have never needed painted road markings, they were simply there for evidence and enforcement purposes. However, that’s not to say that the markings can’t be used by motorists who feel a speeding ticket has been issued unfairly.

If in doubt, don’t speed. If you see a camera, assume it is operational and that you will get caught if you speed past it. In all senses, the risk simply isn’t worth it.

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