In the UK, there is no fixed number of alcohol units that a person can drink and still drive legally because the legal limit is based on the concentration of alcohol in your blood, breath, or urine, not on a set number of units consumed. However, the Department for Transport suggests that men should not drink more than 2 to 3 units and women no more than 1 to 2 units if they intend to drive. A unit of alcohol is defined as 8 grams (or 10 milliliters) of pure alcohol. The legal drink driving limits are:
- In England, Wales, and Northern Ireland: 80 milligrams of alcohol per 100 milliliters of blood or 35 micrograms per 100 milliliters of breath.
- In Scotland: a lower limit of 50 milligrams per 100 milliliters of blood or 22 micrograms per 100 milliliters of breath.
Because alcohol affects individuals differently based on factors like weight, age, sex, metabolism, food intake, and stress levels, even small amounts can push someone over the limit. Therefore, the safest option is to avoid drinking any alcohol if planning to drive. Examples of units in common drinks:
- A pint of lager (3.8% ABV) contains about 2.2 units.
- A 125ml glass of wine (11% ABV) contains about 1.5 units.
- A single 25ml shot of spirits contains 1 unit.
In summary, although men might drink up to 2-3 units and women 1-2 units as a rough guide, there is no guarantee this will keep someone under the legal limit, so no alcohol before driving is safest.
