Our opinion on the legal world, and how it could affect you

Drink Driving! When will you be safe to drive?

22nd Jan 2015

It takes much longer than people think for alcohol to pass through the body leaving them safe to drive. We get consulted by many Clients who have been charged with Drink Driving having been arrested the morning after they last consumed alcohol.

When is it safe to drive?

The simple answer is that it varies from person to person and depends on a a number of factors including

  • your gender
  • your height & weight
  • what food you have eaten & when
  • what alcohol you have consumed & over what period
  • your individual metabolism: how slowly or quickly your body turns food into energy

On average it takes about one hour for the body to rid itself of each Unit of alcohol but it can take much longer. If you need to prove that, for example, alcohol consumed after you ceased driving was responsible for your failing the Breath Test (or that your drinks had been spiked) we would need to get a Forensic Report as the burden of proof shifts to you.

On top of the one hour per Unit you need to add an additional hour because that is roughly how long it takes for alcohol to be absorbed into your blood stream.

Rough Guide to Your Drinks

  • Pint of beer or lager: 4% beers or lagers are 2-5 hour Pints & each Pint takes at least 2.5 hours to leave your blood stream from when you stop drinking
  • 330mls bottles of lager: these are roughly 2 hour bottles
  • Spirits: no mixer makes any difference as the alcohol takes the same amount of time to leave your system whether it is mixed with ice or oramge juice - a 35ml shot is a 1.5 hour drink
  • Glasses of wine: wine glass sizes now vary but a standard glass is now 250ml and if it is a 15% wine one glass is a 4 hour drink. Drink one bottle of 15% wine & you should not drive for 13 hours!


These are just rough guides & the best advice is to

  • not to drink at all if you know you are going to drive
  • know what you are drinking - avoid strange cocktails
  • if you are going to drink work out when you are next going to drive & do the Maths!

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