I've asked this question elsewhere, and they're only advisory, but it might look bad in the event of an accident ,if you ignore them .

Is that even when the restricted speed signs are illuminated as well??

Is that even when the restricted speed signs are illuminated as well??

The ones you asked about are advisory. The ones with red circles are mandatory( as per

anewman's post)

.But ,as said, I'd tend to obey the advisories, as 1) they're a warning.

2) It might look bad if you were involved in an acident , above that speed. ( unless you know that theve been on for a long time ,as I posted above) .

Quick question about speed cameras on the M25. I was driving through them earlier and one of the cameras flashed but not the one above my lane and, even though there were other cars around, none were level with me at the time. Would this just be a random flash or would it have clocked the person in the lane below that camera??

GATSOs are known to "random flash" because radar can give erroneous speed readings which trigger the camera. This is why there are measurement markings painted on the road next to GATSO installations, a GATSO takes two photos about a second apart, and they know the distance traveled during that time thanks to the markings, so they can then calculate the car's speed accurately and ensure it wasn't a dodgy reading from the radar (the two values must be within 10% of each other). Also means they can work out who was speeding on multlilane roads.

Having said all that, doesn't mean someone else got done in one of other lanes.

Edited 17 March, 201214 yr by ckyliu