Just take a short ferry trip to Calais, or down the Eurotunnel, and voila, we are driving in France - a plan that every year thousands of British holidaymakers follow.

Until now, the only thing we had to worry about once we were on French roads was to make sure that we drove on the right side, but things are getting more complicated over there.

A new French driving law imposed from July the 1^st establishes that drivers must carry a breathalyser with them "certified to the French NF standard."

However, according to the Institute of Advanced Motorists (IAM), half of UK motorists are unaware of the new legislation.

Their online poll, with which they obtained data from 2300 respondents also shows that 83% of drivers don't think that carrying a breathalyser will reduce the risks of drink driving. Still, regardless of their opinion about the efficiency of the device, they will be fined if not carrying it.

"Agree with the changes or not, from July 1^st you will face a fine if you don't carry an NF approved breathalyser while travelling in France. While these are a good way of being sure you are safe to drive, if you're going to drink don't drive, and beware the morning after effect," said IAM chief executive Simon Best.

To make sure that the breathalyser complies with the French regulation you must look for a blue circular NF logo - the French equivalent of UK's BSI kite mark.

"We will be looking forward to seeing the evaluation of what impact this new legislation is having. Support is likely to be higher if people can see that carrying a breathalyser actually reduces drink driving," Best added.

It's important to notice that the legal alcohol limit in France is also lower than in the UK - 50 mg per 100 ml of blood, instead of 80mg per 100ml.

The French legislation probably has some commercial interest behind it - surely enough, one knows that you mustn't drive if you drink, no matter what a breathalyser says. Also, if they are so important, why are they not being given away for free? Why are teetotallers and people who never drink when being behind the wheel having to comply with that requirement?

I guess I should ask these questions to the Gendarmerie myself. In the meantime, I'm afraid I will buy a NF standard breathalyser if I decide to cross the Channel.