Drink driving
If you are going to drink, don't drive. If you are going to drive, don't drink. Anything else is a risk, not only to you, but also to other motorists and pedestrians.
Alcohol is involved in about one-third of all serious motor vehicle accidents. As the level of alcohol increases in your body, you have more risk of crashing. If you are above the prescribed blood alcohol content level, as the level of alcohol in your body increases, so does the severity of your fine and/or jail term.
This page contains:
- Standard drinks
- Blood alcohol concentration (BAC) levels
- Penalties for drink driving
- Random breath testing (RBT)
- Increased risk of accident
- More information
Standard drinks
The use of standard drinks can help people to monitor their alcohol consumption and exercise control over the amount they drink.
Different types of alcoholic drinks contain different amounts of pure alcohol. A standard drink is defined as one that contains 10 grams of pure alcohol.
These are all equal to approximately one standard drink:
A middy of beer (285ml) = a nip (30ml) of spirits = a small glass (100ml) of wine = a small glass (60ml) of fortified wine such as sherry.
Please keep in mind:
- Some hotels don't serve standard drinks - they might be bigger. Large wine glasses can hold two standard drinks - or even more!
- Drinks served at home often contain more alcohol than a standard drink.
- Cocktails can contain as many as five or six standard drinks, depending on the recipe.
Blood alcohol concentration (BAC) levels
The blood alcohol concentration (BAC) is the amount of alcohol in the bloodstream. A BAC of 0.05 means you have 0.05 grams of alcohol in every 100ml of your blood.
As the liver metabolises alcohol at around one standard drink per hour, the BAC level drops unless more alcohol is consumed.
BAC is measured with a breathalyser, or by analysing a sample of blood.
Legal BAC limits
There are legal limits as to the BAC level permissible if you are driving:
- experienced drivers (that is drivers over 18 years of age who have been driving for more than 3 years and are not classed as 'professional' drivers), in the ACT have a limit of 'less that 0.05 grams of alcohol per 100 millilitres of blood' commonly referred to as a limit of 'under 0.05.'
- probationary drivers in the ACT, provisional drivers and learner drivers have a limit of '0.02 grams of alcohol per 100 millilitre of blood'.
The following 'professional drivers' must have a limit of '0.02 grams of alcohol per 100 millilitres blood':
- taxi drivers
- bus drivers
- dangerous goods vehicles
- heavy vehicles (gross vehicles mass over 4.5 tonnes)
- Commonwealth vehicles
- learner and P plate drivers
Factors affecting your BAC
The more you drink, the higher your BAC. But two people who drink the same amount might register quite different BACs. There are many factors that will affect this, including:
Body size:
A smaller person will have a higher BAC than a larger person because the alcohol is concentrated in a smaller body mass.
Empty stomach:
Someone with an empty stomach will reach a higher BAC sooner than someone who has just eaten a meal. Food in the stomach slows down the rate at which alcohol passes into the bloodstream.
Body fat:
People with a lot of body fat tend to have higher BACs because alcohol is not absorbed into fatty tissue, so alcohol is concentrated in a smaller body mass.
Women:
After drinking the same amount of alcohol, a woman will almost always have a higher BAC than a male.
Because of all these variable factors, counting the number of standard drinks you consume can only give a rough guide to your BAC. For more detailed information about alcohol and how it effects you, please see the Australian Drug Foundation website.
Drinking limits advice
To stay below 0.05 BAC, drivers are advised to limit their drinking to:
- For men: No more than two standard drinks in the first hour and no more than one standard drink every hour after that.
- For women: No more than one standard drink in the first hour and no more than one every hour after that.
This is a conservative estimate that is designed to minimise the risk of exceeding the legal limit to drive. Because everyone is different, some people need to drink less to maintain a BAC level below the legal limit. This guide is based on advice from the Australian Transport Safety Bureau.
Do not drive if there is any doubt. Make alternative arrangements: call a taxi, catch a bus, get a lift with someone who has not been drinking, or stay overnight.
Penalties for drink driving
The Australian Capital Territory's drink driving laws reinforce the message that drink driving is a serious offence, one that can result in a jail sentence. If the police charge you with a drink-driving offence, the matter will be dealt with by the courts. Penalties for drink driving offences include disqualification from driving for a set period, fines and imprisonment. You should obtain legal advice before you attend court.
Random breath testing (RBT)
Random breath testing is carried out on streets and public places at any time of the day or night. Police officers have the right to stop any vehicle at any time and require the driver to supply a breath sample for screening.
Any person driving a motor vehicle is required by law to have less than a specified amount of alcohol in their blood. If a driver exceeds the level which applies to them the driver has committed an offence.
RBT screening process
- If the reading from a screening instrument indicates that the driver of the vehicle may have exceeded the 'prescribed content of alcohol'
- The driver is conveyed to a police station for breath analysis.
- At the police station, an approved breath analysis operator requires the driver of a vehicle to supply a further breath sample for analysis by the Drager breath analysis instrument. The instrument is recognised by the ACT courts as providing an accurate and lawful reading.
- If the analysis of the sample shows that the person is over the limit, he or she can either be arrested or summoned to appear in court at a later date.
- It is an offence to fail or refuse to supply a sample of breath for screening, or fail or refuse to supply a sample of breath for analysis.
Increased risk of accident
It is safest not to drink alcohol at all if you are going to drive. The more alcohol you have in your body, the more risk you have of crashing.
Facts:
- At 0.05% Blood Alcohol Content (BAC), your risk of being involved in a road crash is double that of a 0.00% reading.
- At 0.1% BAC your risk is more than seven times as high of being involved in a road crash, than at 0.00%.
- At 0.15% your risk increases to 25 times that of driving at 0.00%.
More information
For more information, please see Drink driving laws (Urban Services).