Alcohol, drugs and tiredness all do the same thing to a driver: they slow your reactions and weaken your judgement, often without you noticing. The learner’s test includes the legal alcohol limits, so learn the numbers.
The legal alcohol limits
| Measured in | Ordinary driver | Professional driver |
|---|---|---|
| Blood | Less than 0.05 g per 100 ml | Less than 0.02 g per 100 ml |
| Breath | Less than 0.24 mg per 1 000 ml | Less than 0.10 mg per 1 000 ml |
These are the limits in the K53 manual. Limits can change, and it is your responsibility to know the current law. The only way to be sure you are under the limit is not to drink at all before you drive.
What the law says
- You may not drive, or sit in the driver’s seat of a vehicle with the engine running, while over the limit or under the influence of alcohol or a drug with a narcotic effect.
- Refusing to give a blood or breath sample is an offence.
- Driving under the influence is a criminal offence. The manual notes penalties of up to six years in prison and a licence suspension of six months or more.
What alcohol does to a driver
Alcohol slows your reactions, upsets your coordination and balance, blurs your vision and affects your hearing, makes you drowsy, weakens your judgement and makes you more likely to take risks. Coffee, a cold shower or fresh air do not remove alcohol from your blood. Only time does.
Some medicines also make you drowsy. Read the label, and do not drive if it warns against operating machinery.
Fatigue
Warning signs that you are too tired to drive: trouble keeping your eyes open or your head up, yawning, daydreaming, drifting out of your lane, missing signs or exits, and feeling restless or irritable.
- If you feel sleepy, pull over in a safe place, as far off the road as possible.
- A nap of 15 to 20 minutes helps. Avoid sleeping longer than 40 minutes, and wait at least 10 minutes after waking before you drive again.
- On long trips, take a break about every two hours or 100 km.
- Sleep well before a long drive, avoid driving at the times you would normally be asleep, and share the driving if you can.
Test yourself
These questions come from the K53TestsOnline question bank. Choose an answer to see if you are right.
You shall not drive a motor vehicle on a public road while the concentration of alcohol in your body is ...
Practise more rules of the road questionsAny professional driver would be legally accused of driving under the influence when the concentration of alcohol in their blood is …
Practise more rules of the road questions