What are the effects of alcohol on driving?

Alcohol affects us when it enters our bloodstream and is carried to our brain and other organs. Most of the alcohol is absorbed through our small intestines.

Alcohol is a depressant, which means that alcohol:

• slows brain functions so that you can’t respond to situations, make decisions or react quickly
• reduces your ability to judge how fast you are moving or your distance from other cars, people or objects
• gives you false confidence – you may take greater risks because you think your driving is better than it really is
• makes it harder to do more than one thing – while you concentrate on steering, you could miss seeing traffic lights, cars entering from side streets or pedestrians
• affects your sense of balance – very important if you ride a motorcycle or bicycle
• makes you sleepy.
  

What is Blood Alcohol Concentration?

Blood alcohol concentration (BAC) is the amount of alcohol present in the body, measured in grams of alcohol per 100 millilitres of blood. Studies have shown that as a driver’s blood alcohol level increases, so does the chance of being involved in a crash.
 
Your BAC increases with the quantity and frequency of the alcohol you drink. People absorb alcohol into their bloodstreams at different rates. Body size and general health affect the rate and a female will nearly always have a higher BAC than a male who drinks the same amount of alcohol.  The rate at which you absorb alcohol can also vary from day to day and will be influenced by the rate at which you drink and any food you eat. 

A basic approach is to monitor the alcohol you consume in terms of “standard drinks” which contain 10 millilitres of alcohol per serving. 

It takes a healthy liver about one hour to process the equivalent of one standard drink. There’s nothing you can do to speed up this process — hot coffee and cold showers might wake you up but they have no impact on BAC.

Your BAC can only be measured accurately by either a breathalyser (RBT) or a medically administered blood test.

What is Random Breath Testing?

Detection of alcohol use is based on a quick, unobtrusive roadside test called a Random Breath Test (RBT). This test measures a driver’s breath alcohol concentration and can reliably demonstrate the difference between drivers who have no alcohol in their system, drivers with a level of alcohol under the legal limit and drivers who exceed the legal limit.

Unrestricted mobile random breath testing allows Police to require a driver to submit to a random breath test at anytime, including when they are involved in a crash, commit a traffic offence or appear to be driving under the influence of drugs or alcohol.

All police vehicles are equipped to perform RBT operations and do so regularly, with the aim of reducing and preventing road crashes and making our roads safer.  Police also operate static random breath testing stations across the State.

Where can I go to get further information and/or assistance related to alcohol and other drugs?

If you are:

• worried about your own alcohol or other drug use
• concerned about a friends or relatives alcohol or other drug use
• worried that your teenager may be using drugs
• uncertain about services in your area
• wanting more information
• needing to talk to someone.
  

Contact that Alcohol and Drug Information Service on 1300 13 1340 or visit www.dassa.sa.gov.au for more information.

This confidential and anonymous telephone service operates 24 hours a day, and is staffed by specialist drug and alcohol counsellors who can provide:

• Information on alcohol, illegal drugs and some prescription drugs.
• Counselling and professional assistance in helping you deal with and understand your own or another's alcohol or other drug problem.
• Referral options if you require further ongoing assistance.
• Publications on alcohol and other drug related information and services.