Blood Alcohol Concentration (BAC) and the effects of alcohol

There is a relationship between the concentration of alcohol in the blood (blood alcohol concentration - BAC) and the effects of alcohol, although this varies between individuals. 

In a person of average build, one standard drink will raise the BAC by approximately 0.01 to 0.03% in an hour. See the standard drinks guide on the Australian government's alcohol website.

The body will only process one standard drink per hour. This means, for every standard drink you have, it will take one hour for your BAC to go back to 0.00.

Blood Alcohol Concentration (BAC)

BAC can be used as a guide to what effects alcohol may have on behaviour. People who drink alcohol regularly may show less effect at higher BAC. 

  • A BAC of up to 0.05 g% is likely to cause a feeling of wellbeing. Likely effects are being talkative, more relaxed and more confident.
  • A BAC of 0.05 to 0.08 g% is likely to make you at risk of impaired judgment and reduced inhibitions.
  • A BAC of 0.08 to 0.15 g% is likely to put you in a risky state. Likely effects include slurred speech, impaired balance and coordination, unstable emotions and possibly nausea and vomiting.
  • A BAC of 0.15 to 0.30 g% will put you at high risk with likely effects to be inadequate breathing, unable to walk without assistance, loss of bladder control and possibly loss of consciousness.
  • A BAC of over 0.30 g% is likely to put you in a coma or result in death.