Any amount of alcohol affects your ability to drive. There is no foolproof way of drinking and staying under the limit, or of knowing how much an individual person can drink and still drive safely.
Each person's tolerance to alcohol depends on a range of factors including:
- current stress levels
- whether they have eaten recently
- amount of alcohol
If you drive at twice the legal alcohol limit you are at least 30 times more likely to cause a road crash, than a driver who hasn't been drinking.
So the only safe option is not to drink alcohol if you plan to drive, and never offer an alcoholic drink to someone else who is intending to drive.
What is the drink drive legal limit?
The legal alcohol limit for drivers in Great Britain is:
- 80 milligrammes (mg) of alcohol per 100 millilitres (ml) of blood (80mg/100ml), or
- 35 microgrammes of alcohol per 100ml of breath, or
- 107mg of alcohol per 100ml of urine
The limit has remained unchanged since its introduction by the Road Safety Act 1967, which also gave the police powers to breath-test drivers suspected of drink driving.
What are the current penalties?
For exceeding the legal alcohol limit for drivers:
- up to 6 months in prison
- a fine of up to £5000
- a minimum of 12 months' disqualification (3 years for a second offence within 10 years)