Jun 27 2022

What is the drink driving limit?

The drink driving limit in England and Wales is 35 micrograms (μg) per 100 millilitres (ml) of breath, 80 milligrams (mg) per 100ml of blood, and 107mg per 100ml of urine. The limits are different in Scotland, but as we do not work in Scotland you will have to find a local solicitor if you want to know about the limits there.

The real question that most people want to know is how much they can drink and not exceed the drink driving limit. Unfortunately, that isn’t an easy question to answer.

Your alcohol level will depend on a number of factors, which makes it very difficult to predict what quantity of alcohol will put you over the limit. As a general rule, men can consume more alcohol than women, and bigger people can consume more than smaller people. That said, because your alcohol level has a lot to do with the water content in your body, bigger people who are carrying a lot of fat will be able to consume more than a person the same size who is carrying more muscle and less fat.

We acted in a case in which a professor of toxicology looked at the amount of alcohol our client had consumed and gave evidence that if he had been present he would have advised our client that he was safe to drive; however, when he conducted the scientific tests he found that the client’s alcohol consumption was enough to put him over the limit! Even very experienced professors of toxic struggle to get these judgements right.

A lot of people think that eating will have an impact on their alcohol level. In fact, whether you drink on an empty stomach, or a full stomach makes such a miniscule difference to your alcohol level that toxicologists ignore your food consumption entirely when calculating a person’s predicted alcohol level based on the drinks they consumed! Eating before or while drinking will help you feel less drunk, but it will not change the amount of alcohol that enters your blood stream and so all of the methods used by the police to detect alcohol will still return the same result whether you feel the impact of your alcohol consumption or not.

The best advice is not to drink alcohol if you are going to drive. If you are going to drink or you have had a drink the night before driving, the next best advice is to buy a good quality breath test device, follow the instructions and use it

If you do find yourself accused of a motoring offence and require specialist legal advice you can call us on 020 8242 4440 or sent an email via our contact page.