Nobody knows this rule about speed cameras, but it is essential to avoid fines.

Few drivers know this, but there are precise distances between the radar signs and the devices themselves.

Although we see many of them on the side of the road, the signs indicating the proximity of a speed camera do not always have the desired effect. Supposed to warn that a device is going to check the speed of their vehicles a few meters further, they have the gift of provoking a sort of panic among some motorists who, at the sight of them, use and abuse the brake pedal. Result: a slowdown is created and that's how we see traffic jams forming, especially when traffic is already heavy.

All this wouldn't happen if drivers knew how far these speed camera signs were from the speed cameras themselves. Not to mention that it would help them know at what precise moment to check their speed or even slow down to avoid being caught speeding and having to pay a fine, most often accompanied by the loss of points on the driving license. Because the distance between the sign and the speed control device is almost always the same in France, within a few meters, depending on the type of road on which it is installed.

©&amp ;nbsp;SIPA

In fact, the higher the speed limit on the road, the greater the distance. On roads limited to 70 km/h, you have to allow 300 meters between the sign and the radar. It is 400 meters on roads with a speed limit of 80 or 90 km/h, while the gap climbs to 600 meters on motorways. In concrete terms, the speed of 130 km/h on a motorway, you can allow about fifteen seconds, between 16 and 17 to be precise, to pass between the sight of the sign and the place where the speed of your vehicle will be measured. You should know that the distance can vary by around fifty metres depending on the environment. Also, when a radar is installed in a city, it is most often at the entrance to it that the signs “Frequent radar control” or “Automatic controls” are set up and not at a specific distance from the radar(s).

As it happens that you are not always focused on your GPS or Smartphone when driving, and therefore miss certain alerts, knowing how many meters away the radar is once you pass in front of the warning sign can be useful. In France, there is no law requiring you to report the proximity of a radar. But the government services have chosen to install a sign before each automatic speed control radar. A way, no doubt, to calm (a little) the discontent of motorists who have seen these devices spring up like mushrooms on the roadsides in about twenty years.

While fixed radars are indicated, this is not the case for mobile radars on board police vehicles or private companies, any more than for red light radars. But the best thing to do to avoid the risk of being flashed is obviously to respect the speed limits everywhere and all the time.