Jeremy Clarkson tilts at windmills

Following last week’s round-up of road news by El Reg – and a number of reader comments about the new “average speed” cameras that are being rolled out across the UK - it's nice to see Jeremy Clarkson taking up the subject in his column in the Sun. (Just kidding- we know this has been a bugbear of JC since the dawn of time).

According to Speed Cameras UK – a website dedicated to all things related to speed cams - SPECS average speed camera systems use state of the art video systems with Automatic Number Plate Reading (ANPR) digital technology. SPECS speed cameras work out the vehicle's average speed, given the time it takes to drive between the two camera positions.

A minimum of two cameras, each fitted with infra red illuminators so they can work day or night, are mounted on gantries above the road, either at the roadside or in the central reservation.

As vehicles pass between the entry and exit camera points their number plates are digitally recorded, whether speeding or not. Then, by ANPR recognition, the images on the video of matching number plates are paired up, and because each image carries a date and time stamp, the computer can work out your average speed between the cameras. There is no film used in SPECS.

Jeremy Clarkson raises the issue also mentioned by El Reg readers, that if you switch lanes between start and exit points, you will avoid being done.

Is this true? It sounds so unlikely that it might be. Or it could just be a new urban myth in the making.

We sorry to report that the latter appears to be the case. According to Geoff Collins, marketing director of Speedcheck Services Ltd, which manufacture the SPECS system, the idea that you can avoid points on your license by changing lanes is “categorically untrue”.

It has never been true from a technical perspective: after all, the only thing this system needs to do is recognise a number plate twice and then apply an algorithm to the two timestamps recorded. Nor, sadly, do Home Office guidelines prevent the cameras being used in this way.

According to Collins, the need for Home Office Type Approval (HOTA) may have given rise to the confusion. This, he says “is a form of rigorous testing that any system must undergo before it can be used for enforcement. Until recently, the only HOTA available applied to cars maintaining their lanes.

“However, a new test schedule was carried out last year, which means that average speed checking can be applied even where cars change lanes.”

Debate continues as to whether this speed system improves driving – or encourages bad habits. There can be little doubt that Jeremy Clarkson does the latter, as he is alleged to have suggested that the best way to deal with this new technology is to pull over after the first camera: take a five-minute break; and then zoom through the second at 120mph.

We do not advise you to try this. We also point out that if anyone wishes to achieve a particular average speed, they can do so by driving for equal periods of time by the same amount above and below the desired average. This does not work if you try to drive for equal distances in this manner. ®