Alcohol impairs a person’s ability to control a vehicle. Research suggests that at a blood alcohol concentration level of 0.05, the risk of being involved in a traffic accident is double that of a person who has not been drinking at all.
If you have a full unrestricted licence your blood alcohol level reading must be below 0.05 if you want to drive.
If you are a learner (L Plate) driver or provisional (P Plate) driver you must have a 0.00 blood alcohol reading.
You can be asked to do a breath test by police at any time you are driving, or police reasonably suspect you have been driving. Generally, failing or refusing to provide a sample is an offence. If you are incapable of providing a breath sample because of your physical condition, police may ask you to provide a blood sample instead, if appropriate.
You may only refuse to do a test if you are deemed incapable of providing any sample (eg. you have a medical condition which prevents you from doing the test, or you are injured or passed out and cannot give a sample), or if more than 4 hours has passed since the time that you are believed to have driven the motor vehicle.
If you believe your result is incorrect you should seek legal advice as to how to challenge your test.
If you show a higher reading than 0.05, and you hold a full licence, the mandatory minimum punishment is 3 months suspension of your license and a large fine, both becoming more severe the higher the reading is and whether or not you have any prior drink driving offences.
If you are a learner or provisional driver, and you register more than 0.00, you may have your licence cancelled, and you will have to begin your learner or provisional stage again after the disqualification period.
If you do lose your licence or have it suspended, you may be able to apply for a restricted licence to be able to drive during specific times of the day (for instance, being able to drive to and from work).