Alcohol and drugs

Alcohol and drugs: You may not drive or even sit in the driver's seat with the engine on if You've taken narcotic drugs (even prescription drugs) You are…

By K53 Study Guide · Updated

The law says

  • You may not drive or even sit in the driver's seat with the engine on if
    • You've taken narcotic drugs (even prescription drugs)
    • You are a normal driver and you have a blood alcohol level of over 0.05g per 100ml blood (0.24mg per 1000 ml breath)
    • You are a professional driver and you have a blood alcohol level of over 0.02g per 100ml blood (0.10mg per 1000 ml breath)
  • If asked by a law enforcement officer, you may not refuse to give a blood or breath sample
  • You may not smoke till the sample has been taken
  • At the time of this CD being printed, there was a proposal to bring in new laws that make it illegal for drivers to have any alcohol at all in their systems for the first three years after getting their licence. Please check to see if this law has come into effect by the time you get your licence.

Factors that affect blood alcohol levels

If two people drank the same amount they could have different blood alcohol levels, so it's impossible to say exactly what all people can drink to stay under the limit. Some of the factors that affect blood alcohol levels are:
  • Gender: in general, males' blood alcohol levels go up more slowly than females'
  • Weight: the lighter you are, the faster your blood alcohol level goes up
  • General level of health: if you are ill it goes up faster
  • How fast you've been drinking (slower is better)
  • What else you've eaten or drunk, or other drugs you have taken

General guidelines for staying under the limit

  • As mentioned, it is not possible to say exactly how many drinks you can have before being over the limit, because it depends on so many factors. Rather drink less and be sure you are under. But to give you an idea, you should stay below:
    • 1-2 drinks for females (not drinking faster than 1 drink per hour)
    • 2-3 drinks for males (not drinking faster than 1 drink per hour)
  • Alcohol takes time to break down in your blood, so if you had a heavy night and didn't drive, you could still be over the limit if you wake up the next morning and drive.
  • After you stop drinking allow at least an hour for each drink you had to break down.

One 'drink' is

  • One glass table wine (125ml)
  • One can/bottle beer (340ml)
  • One shot of spirits (25ml)