Always maintain a safety margin around the vehicle by keeping distances and by driving at appropriate speeds. Having a sufficient safety margin could mean the difference between safely avoiding a collision and being involved in a fatal crash.
Rear-end collisions are almost exclusively caused by one vehicle tailgating another, and not being able to stop in time as a consequence.
Give yourself time to react by creating a ‘buffer’ between yourself and potential hazards. For example:
If something moves into your safety margin - slow down to maintain your buffer.Following too closely (A) dramatically increases the risk of rear - end collisions (B)
When you spot a potential hazard, you should prepare to stop by smoothly slowing down while kee
If you feel that a vehicle behind you is too close, gently slow down if safe. A lower speed will give you more time to respond to possible hazards and prevent sudden braking, which may cause a collision with the vehicle behind you.
How much safety margin you need is determined by a combination of the time you need to react and the time you need to respond.
You should have a sufficient distance to the vehicle in front so that you have time to react and safely stop or steer away to avoid a collision.
A general rule is to have at the very least a 3-second gap to the car in front of you, called the ‘3-second rule’.
You can measure this by a simple test:
Think of reaction time as the time needed to:
Think of response time as the time needed to respond. Braking is often the only appropriate response to avoid a severe crash, as swerving may result in a more severe crash (e.g. a head-on collision).
A fit and alert driver requires about 1.5 seconds to react to a hazard and responding also takes time. That's why you should keep a following distance of at least 3 seconds.
Keep in mind that a 3-second gap leaves no room for error, so it's often a safer option to have 4 seconds or more. Conditions are rarely perfect, and you might need a much longer time to react and respond safely.
You should always drive at a speed suitable to the conditions - slow down and increase your following distance when:
Additionally, increase the following distance and be extra careful:
Always be extra careful around heavy vehicles as they take longer to change direction and stop. Stay out of their safety margin.
Vehicles with a combined length of at least 7.5m (including a trailer) are considered 'long'.
A long vehicle following another long vehicle must drive at least 60m away from it. However, there are two exceptions to this rule: