Know your limits

The letter of the law tells us the limits are:

Level of alcholEngland,Wales and Northern IrelandScotland
Micrograms per 100 millilitres of breath3522
Milligrammes per 100 millilitres of blood8050
Milligrammes per 100 millilitres of urine10767

However that tells us relatively little as the way alcohol sits in our body depends on:

  • Weight
  • Age
  • Sex
  • Metabolism (the rate your body uses energy)
  • Type of alcohol consumed
  • Concentration of alcohol drunk
  • Food consumed
  • Mood

So How can we really assess if we are definitely legally safe to drive?

The most certain way of checking is using the same kit that the Police use to evidence, so that is either a blood test, not something that we really want to encourage, or breathalysing; something we think the general public who drink and use vehicles should never be without.