Saving Lives Together

Drink driving

people died in alcohol related crashes in 2020

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The summer holiday season is one of high risk, where low-level drink driving is more likely to be justified as a ‘one-off’ or being within self-justified limits. 

The decision whether to drink and drive is unspoken. It’s a silent conversation you have with yourself. And that conversation can at times be highly conflicting. It’s a calculated risk you take in the moment as you weigh up the pros and cons. But nothing is worth the risk of drink driving, even once. 

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Drink driving penalties

See the road rules and penalties section for information on drink driving laws.

Staying Under 0.05

It is best you don't drink anything before driving. 

Determining your blood alcohol concentration (BAC) level is difficult as it is affected by a number of factors, including:

  • The amount of alcohol you drink.
  • The period over which alcohol was consumed.
  • Your body mass.
  • ​Whether or not you have eaten.
  • Your fitness level and health of your liver.

If you do have a drink, as a guide: 

  • Men should not drink more than 2 standard drinks in the first hour and 1 standard drink every following hour. 
  • Women should not drink more than 1 standard drink every hour. 

Note: Learner and provisional drivers must have a zero BAC when driving.

How Much is a Standard Drink?

Type% Vol.Standard Drinks
Mid strength beer glass3-4% Alc/Vol0.8 standard drink per 285 ml
Mid strength beer can3-4% Alc/Vol1 standard drink per 375 ml
Wine10-14% Alc/Vol1 standard drink per 100 ml
Spirits37-43% Alc/Vol1 standard drink per 30 ml
Pre-mixed drinks5% Alc/Vol1.5 standard drinks per 375ml
Full strength beer glass4-6% Alc/Vol1 standard drink per 285ml
Full strength beer can4-6% Alc/Vol1.5 standard drinks per 375ml

WA Alcohol Interlock Scheme

Western Australia introduced an Alcohol Interlock Scheme on 24 October 2016, with the aim of reducing the road safety risk posed by drink drivers on WA roads. This scheme will be user-pays and apply to high-end and repeat drink drivers.

What is an alcohol interlock?

An alcohol interlock stops a vehicle starting if the driver (or rider) has been drinking. This technology helps people to separate drinking from driving. An alcohol interlock is a breath testing device which, when installed in a vehicle or motorcycle, prevents it from being operated if a breath sample reads above a certain amount of alcohol.

Why change the rules?

Despite 20 years of anti-drink driving messaging, alcohol remains a factor in a quarter of fatal crashes.
Alcohol interlock schemes already in place across Australia and around the world have proven to reduce repeat drink driving by approximately 64%. Based on WA drink driving offences, it is expected that between 4,000 and 6,000 drink drivers will be required to fit an alcohol interlock to their vehicles in WA each year.

How does the alcohol interlock scheme legislation work?

As of 24 October 2016, interlocks are now mandatory for drivers who:
  • Are convicted of driving with a BAC 0.15 or over.
  • Are convicted of dangerous driving causing death, bodily harm or grievous bodily harm, where they're under the influence of alcohol to such an extent as to be incapable of having proper control of a vehicle.
  • Commit a second drink driving offence of any kind within 5 years.
  • Fail to comply with a request to provide a breath sample to a member of WA Police.

This is a representation of the legislation only - please see the Comprehensive Q&A for more detail. The penalties associated with the Alcohol Interlock Scheme are additional to existing fines and disqualifications for alcohol-related offences. After an offender has served the applicable disqualification period, their licence will be endorsed with an alcohol interlock condition.

What will it cost you?

Each individual on the Alcohol Interlock Scheme must cover all costs for use of the interlock device including: installation, rental, servicing and removal costs. The total estimated cost over six months is $1,600. This estimate is subject to change. In some circumstances further costs may apply - see the Comprehensive Q&A for more detail.

Alcohol assessment and treatment

Drivers assigned to the Alcohol Interlock Scheme who breach the requirements may be required to attend alcohol assessment and treatment. Alcohol assessment and treatment includes six one hour sessions with a trained alcohol and other drug counsellor, aimed to help support the driver to separate alcohol use from driving.

More Resources  

Drug Driving

The effects of illicit and prescription drugs on drivers vary, from giving the driver false confidence to slowing down reaction times, ultimately putting others at risk.

In Western Australia, drivers can be subject to roadside drug tests, with the aim to reduce the risk posed by drug drivers on WA roads.​
Driving under the influence of illicit or prescription drugs impairs your ability to operate your vehicle safely and puts other road users at risk.
The effects drugs have on your driving ability include the following:
  • Gives the driver a false confidence, increasing risk-taking behaviour.
  • Slows the driver's reaction time.
  • Distorts the driver's visual perceptions.
  • Decreases ability to coordinate reaction when driving.
  • Causes the driver difficulty in judging distances.
  • Can increase the risk of having a crash.

Drug Aware website                                                                                          Mental Health Commission


Community Resource 1
It doesn’t take much to put you over the limit. For men, it’s no more than 2 standard drinks in the first hour and 1 each hour following. For women, it’s no more than 1 per hour. Plan ahead. Don’t drink and drive.Download
Community Resource 2
It doesn’t take much to put you over the limit. For men, it’s no more than 2 standard drinks in the first hour and 1 each hour following. For women, it’s no more than 1 per hour. Plan ahead. Don’t drink and drive.Download
Community Resource 3
Drink and drug driving fact sheetDownload