Drink driving - exploding the myths

What will your drink cost you 2 smMyth One: 'I know how much I can drink to stay below the legal limit.'


You must not drive if you are above the following limits in the UK (Scotish limits are different):

  • 35 micrograms of alcohol per 100 millilitres of breath
  • 80 milligrams of alcohol per 100 millilitres of blood
  • 107 milligrams of alcohol in 100 millilitres of urine.

In Scotland it is

  • 22 micrograms of alcohol per 100 millilitres of breath
  • 50 milligrams of alcohol per 100 millilitres of blood
  • 67 milligrams of alcohol per 100 millilitres of urine

(Correct on 27 Sept 2017. Always check The drink drive limit page on the gov.uk site)


It is also an offence to drive whilst unfit; the level is irrelevant if you and your driving are deemed to be impaired.

  • It is impossible to say how much alcohol you can drink and stay below the legal limit. Alcohol intake depends on a number of factors, including the individual's response to alcohol
  • Your system continues to absorb alcohol even after you've finished drinking
  • Without taking a breath test there is no way of knowing how much alcohol is in your system.

The best way to make sure you are not over the limit is not to drink and drive.

Myth Two: 'Drink doesn't affect the way I drive.'


  • If you have drunk at least twice the current drink drive limit then you are 50 times more likely to be involved in a fatal collision.
  • The prescribed level was set at the point where your reaction time doubles

Myth Three: 'I haven't had a drink since last night, I can't be still over the limit.' 


  • Many people drive the morning after; their alcohol reading is often still over the prescribed limit but remember, if driving is affected or a collision occurs, the level is irrelevant.
  • Take a Saturday night's drinking:

    • At midnight you may have 200 milligrams per 100 millilitres of blood in your system. This is 2½ times the drink drive limit
    • At 7.30 am there will still be 90 milligrams per 100 millilitres in your system - you are still over the drink-drive limit
    • By lunchtime you will still have about 20 milligrams within your system, not above the limit, but still enough to adversely affect your driving.  

Myth Four: 'I'll never get caught.'


  • More than half a million breath tests are carried out every year in England and Wales.
  • In Devon and Cornwall in 2015 there were 14,185 roadside breath tests and 1,692 arrests.
  • It’s not just the police who worry about drink drug drivers, many calls to police are from concerned friends and family

If you are convicted of drinking and driving:

  • You will have a criminal record
  • You will be disqualified from driving for at least a year
  • Your next vehicle insurance premium will significantly increase
  • You will have difficulty hiring a car for the next 10 years
  • You may have to retake your driving test and attend rehabilitation to regain your licence.

You may even be imprisoned..

Doesn't matter where you live drink driving is never a good idea.

Scottish government Drink Driving campaign - 'Blue light'

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