The drunk-driving limit is 50mg of alcohol per 100ml of blood.
Wine is available with meals in French motorway service areas - a fact that surprises a lot of visitors. But don't forget that the blood alcohol limit in France is very low. The best advice is the same everywhere - don't drink and drive.

It is now obligatory for all vehicles (including motorbikes) driving inFrance to carry a breathalyzer or alcohol-level test. The law came intoforce on July 1, 2012. Single-use certified breathalyzers are nowbecoming available in supermarkets, chemists and garages throughoutFrance, at a cost of about 1 €uro each. So the cost is minimal.

The new law does not oblige drivers to self-test after having a drink. But those who plan to self-test to be on the safe side should have at least two breathalyzers in the car, if not more.

It is an offence to hold and use a cell phone while driving in France. Hands-free use of cell phones is not illegal. Though many drivers ignore this rule, traffic police are clamping down on drivers holding phones to their ears while driving, and drivers are liable to an on-the-spot fine of 130 Euros and 3 penalty points if they have a French driving license.

These have been banned in France since late 2011. Drivers using radar detectors (speed camera detectors) are liable for a fine of 1,500 Euros and 6 points off their license. This applies to specific radar warning devices, such as the Coyote, which must have their software updated to remain legal.

With regard to TomToms and other GPS systems, which have speed camera locations programmed in to their software, the situation is confusing. These are not officially 'radar detectors', but manufacturers are obliged to make new software available, and most have done so. Tomtoms and other GPS systems are technically in breach of the law if they still have radars listed in their Points of Interest software; and even if it is not clear how roadside police can stop and check for offending software, rather than hardware, drivers are warned to err on the side of precaution and download the latest map software for France. This is advisable anyway, since older software is not up to date with regard to new routes, new speed restrictions, and other changes. For both existing radar warning devices and GPS devices, current radar information is being replaced with warnings to announce 'danger zones', many of which will be areas with speed cameras.

Seatbelts must be worn at all times when driving in France, by both adults and children, and both in the back and front seats. Rear passengers can only travel without seatbelts in the back of older cars in which they are not fitted.

Children under 10 years of age must travel in the back, using an appropriate child seat or booster seat. Babies are allowed to travel in the front passenger seat, but only when placed in an approved rear-facing baby seat and the airbag is turned off.

Dipped headlights must be used in poor daytime visibility. Motorcycles over 125cc must use dipped headlights during the day at all times.

You should only use your horn in an emergency.

If you want the car in front to give way, flash your headlights.
In built-up areas, if there's no yellow diamond sign, you must give way to any cars coming out of a side turning on the right.
The last car in a queue of slow-moving traffic must use their hazard lights as a warning.
Take care when overtaking, allow more space between you and the car in front so you can see further down the road ahead.
Take care in built-up areas where the old rule giving priority to traffic coming from the right (Priorité a droite) still applies unless a yellow diamond indicates you have priority. On roundabouts you generally give priority to traffic already on the roundabout, in other words, coming from your left as you enter the roundabout.