Most rear-end crashes have one cause: the driver behind was too close to stop in time. The K53 rules set a minimum gap in seconds rather than metres, because a gap measured in time grows automatically as your speed goes up.
The minimums
| Situation | Minimum following distance |
|---|---|
| Light motor vehicles and motorcycles | 2 seconds |
| Heavy motor vehicles | 3 seconds |
| Rain, a slippery surface, poor visibility, or someone following you too closely | More than the minimum |
In the practical driving test, the examiner expects at least 3 seconds and penalises you for a shorter gap. Practising with three seconds from your first lesson makes the test easier.
How to measure it
- Pick a fixed point ahead, such as a lamp post, a road sign or a shadow on the road.
- When the back of the vehicle in front passes it, start counting: one thousand and one, one thousand and two.
- If you reach the point before you finish counting, you are too close. Ease off and count again.
Why the gap matters
Your stopping distance has two parts: the distance you travel while you notice the danger and move your foot to the brake, and the distance the vehicle needs to brake to a stop. Both grow with speed, and braking distance grows much faster. A safe following distance means that if the vehicle ahead stops suddenly, you can stop in time without swerving.
When someone is too close behind you
Do not brake to warn them and do not speed up. Increase the gap in front of you instead, so that you can brake gently if you need to, and let them pass where it is safe. When someone overtakes you, keep left and do not accelerate until they are past.
Test yourself
These questions come from the K53TestsOnline question bank. Choose an answer to see if you are right.
A safe following distance, at all speeds, for motorcycles and light vehicles is...
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