Know your limit!
The legal alcohol limit for driving is 80mg of alcohol per 100ml of blood. There is no failsafe guide to the amount of alcohol that you can safely consume and stay under the limit, or of knowing how much you can drink and still drive safely.
Your tolerance to alcohol depends on a range of factors including:
- weight
- gender
- age
- metabolism
- current stress levels
- whether you have eaten recently
- amount of alcohol
Even a small amount of alcohol and being well below the legal limit, seriously affects your ability to drive safely. Your ability to judge speed and distance may be impaired, your reaction times may be slowed and your ability to see risk seriously affected.
Never drive if there’s even a slim chance you are still ‘under the influence’.
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.
How long will it take for alcohol to leave your system?
Most people are not aware how long it takes for alcohol to leave the system. You can still be over the drink drive limit the morning after, even if you feel fine. Drinking coffee, sleeping, or having a shower don’t work. Time is the only way to get alcohol out of your system.
On average it takes 1 hour for alcohol to be absorbed into your bloodstream. It then takes at least 1 hour for your body (assuming you have a healthy liver) to rid itself of each unit of alcohol. You should count the hours it takes for each drink to leave your system from the time you finish your last drink.
Below is a guide to help you calculate when you should stop drinking if you are driving the following day.
- 4% beers and ciders - Average strength drinks like Fosters and Guinness are two and half hour pints. Each pint takes at least two and half hours to leave your blood stream from when you stop drinking. Therefore if you have four pints and stop drinking at midnight, you are not safe to drive until after 11am the next day.
- 5.5% beers and ciders - Stronger drinks like Stella, Kronenberg and Strongbow are three hour pints. Drink four pints of Stella and you can't drive for at least 13 hours from finishing your last pint. So if you call it a night at midnight you are not safe until after 1pm the next day.
- 5% bottles – 330ml bottles of Becks, Bud, Stella, or 275ml bottles of WDK, Smirnof Ice are two hour bottles. Drink six of these up till midnight and you are not safe until after 1pm the next day.
- Wine - One 250ml glass of 13% wine is a three and a half hour drink. Drink a bottle of it and you'll need to leave 11 hours before driving or 11am if you stop at midnight.
- Spirits - A double shot of a spirit is a three hour drink. Drink three of these and you will need to leave 10 hours before driving, meaning that if you finish drinking at 11pm you are not safe to drive until 9am the next day.

