Average Speed Limits

[denis567]

When travelling on a stretch of road (usually at road works) where there are signs saying 'Average Speed Checks' do the cameras record all vehicles or is it just the ones exceeding the speed limit when they pass the first camera.
If this is so, is there anything to stop a driver speeding between the cameras, assuming he knows where they are.

[sara3]

it records them all temporarily, and when you pass the next set of cameras they recognise if the time span is inappropriate (if you were speeding) and you'll get a dodgy photo in the post!

if you're only going to pass one set of cameras I would guess that you would get away with it.

[sddsddean]

The theory is that they record all vehicles (although some will be missed...hidden behind lorries etc), so you have got to do an average of (say) 50 between the cameras. So you could belt along at 80 part way then slow down to 20, but it seems a bit pointless...just stick to 50. I once spoke to a mate of mine who was something to do with Surrey CC road safety and he told a few years ago about people doing exactly what you describe on the M25. They got over 1000 vehicles in one day!

[jd_here]

Why not try writing to your local Road Safety Partnership and ask them under 'The Freedom of Information Act' to let you know exactly how and when the cameras are working. They will be obliged to tell you

[doglady]

Personally, I think these are great. They seem to keep the traffic flowing much better than normal speed cameras where everyone brakes to get under the limit as they go through the camera, which then makes the person driving too close behind brake and sets up a nice chain which ends up in a traffic jam.

[buildersmate]

I think most us know HOW they work - see the first reply - they measure the time taken for the detected vehicle to travel between the 2 camera points. If the time taken is less than a calculated figure, the vehicle's average speed was exceeding the limit for the section.

[Panic Button]

At one time you could beat the system simply by changing lanes, but I think technology is catching up now.

[pagey]

A friend of mine saw the sign 'average speed cameras' and asked... why don't they get decent ones?!

[Compostella]

Have a look at this

http://www.thisislondon.co.uk/news/article-233 70879-details/Drivers+can+avoid+speeding+ticke ts...by+changing+lanes/article.do

[denis567]

Thanks Compostella. Very interesting