Ultimate Guide to UK Stopping Distances

You may remember memorising stopping distances for your driving test, but can you remember them now? The stopping distance is the space required to bring your vehicle to a halt from the moment you notice a hazard. With tailgating being one of the most common causes of car accidents in the UK, it’s really important to know how far away you should be from the car in front and what factors can cause these distances to alter.

What are the correct UK stopping distances?

There are two aspects you need to take into account when calculating the stopping distance, these are thinking distance and braking distance. Thinking distance is the distance you travel while your brain interprets what you are seeing and makes the decision that you need to apply the brakes. Braking distance is the distance the car travels once the brakes have been applied before it comes to a complete standstill. So for the overall stopping distance, you simply add the thinking distance to the braking distance to get your final figure.

Of course, there are many other factors at play, so these figures cannot ever be perfectly accurate, but they are a guideline based on an average-sized family car in fine weather conditions.

Thinking Distance

• Speed: 20 = Thinking Distance: 6 metres
• Speed: 30 = Thinking Distance: 9 metres
• Speed: 40 = Thinking Distance: 12 metres
• Speed: 50 = Thinking Distance: 15 metres
• Speed: 60 = Thinking Distance: 18 metres
• Speed: 70 = Thinking Distance: 21 metres

Braking Distance

• Speed: 20 = Breaking Distance: 6 metres
• Speed: 30 = Breaking Distance: 14 metres
• Speed: 40 = Breaking Distance: 24 metres
• Speed: 50 = Breaking Distance: 38 metres
• Speed: 60 = Breaking Distance: 55 metres
• Speed: 70 = Breaking Distance: 75 metres

Total Stopping Distance

• Speed: 20 = Stopping Distance: 12 metres
• Speed: 30 = Stopping Distance: 23 metres
• Speed: 40 = Stopping Distance: 36 metres
• Speed: 50 = Stopping Distance: 53 metres
• Speed: 60 = Stopping Distance: 73 metres
• Speed: 70 = Stopping Distance: 96 metres

What factors affect the braking distance of a vehicle?

So once you know the stopping distances for an average car in average conditions, you need to think about the different conditions that could alter those distances further. Factors to consider include…

The weather

Perhaps the most obvious factor that will massively impact stopping distances is the weather conditions. Braking distance will increase if the road surface is slippery, so that could be in the ice and snow and also in the rain. Low visibility, such a fog, snow or driving rain can also create an increase in the thinking distance as it takes longer for the driver to realise that they’re in a situation where the brakes need to be applied.

The vehicle

The condition of the brakes will have an impact on stopping distance so be sure to have your brake pads checked regularly and replace if necessary. Under-inflated tyres can increase stopping distances so check your tyre pressure too. Worn tyres will have less grip and so will add to the problem. What may also surprise you, is that in tests, budget tyres require extra stopping distance when compared to premium tyres, so do think about this next time you need to buy a new tyre. Spending a bit extra on premiums might just be the wisest choice when it comes to safety.

The driver

The human factor can also play a massive part in determining the stopping distance at a particular point in time. Thinking distances will increase if the driver is tired and that’s one factor that we really do need to bear in mind more. Sadly tiredness really does kill. Distractions also cause our reactions to be slower as we take longer to notice we need to slam on the brakes. A mobile phone conversation, loud music, the kids in the back, they can all become distractions that increase stopping distances. Of course, being under the influence of drugs or alcohol will have an adverse effect on stopping distances, and so can age. There’s not a lot we can do about the slowing of our reactions as we get older, but we can be aware that this can happen and just leave that little extra space to be on the safe side.

The condition of the road

The road surface itself may also alter your stopping distances. Rainfall on a hot road on a summer’s day can cause the road surface to be greasy and increase stopping distances. There may be oil on the road, and loose surfaces such as gravel can also cause problems.

What is the 3 second rule in driving?

The three second rule is a system recommended by The National Safety Council as an easy way to help you keep a safe distance between you and the vehicle ahead. What you need to do, is select something on the roadside ahead of you. A tree, road sign or suchlike When the car ahead of you passes this marker, start counting the seconds, with 1-1000, 2-1000, 3-1000 as you would when calculating the distance of a storm between lightning strike and thunder clap. As you pass the marker yourself, if you counted more than three seconds, then your distance from the car in front is adequate. If you are under 3 seconds then you need to allow some more space.

How does ABS shorten stopping distance?

ABS or anti-lock braking systems are now standard on most modern vehicles. They help to decrease stopping distances by pumping the brakes when the car senses the vehicle is skidding. Each wheel has a sensor, so when the wheels lock or stop moving, the brakes are automatically pumped incredibly fast, literally hundreds of times a second. This then helps you to maintain control of the vehicle and so come to a halt more quickly, in essence, shortening the stopping distance.

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