Speed
Many people think that speed cameras are there to make money and that police time is being wasted trapping and prosecuting 'innocent' drivers - time that could be better spent catching 'real' criminals. Statistically 'real' criminals rarely kill people, but speeding motorists do!
Over four times as many people die each year on our roads than do as a result of violent crime. It is important as a nation that our driving attitude and behaviour changes to prevent many unnecessary casualties and inexcusable deaths.
In 2008 there were just under 28,000 casualties in collisions where a speed contributory factor was reported. These include 586 fatalities and over 4,000 serious injuries, acounting for 25% of road deaths and 18% of serious injuries (reported Road Casualties, Great Britain, 2008, DfT).
For pedestrians the speed at which they are hit is the difference between life and death.
| Vehicle speed | Pedestrians killed |
|---|---|
| 20mph | 5% of pedestrians are killed |
| 30mph | 20% of pedestrians are killed |
| 40mph | 90% of pedestrians are killed |
| Over 40mph | Forget it |
Source: DfT 2005
REMEMBER: It's 30 for a reason.
Some speeding facts
- Around two-thirds of all collisions where people are killed or injured happen on roads where the speed limit is 30mph or less.
- 7 out of 10 drivers regularly break the speed limit - usually by about 5mph.
- An average family car travelling at 35mph will need an extra 21 feet (6.4 metres) to stop than one travelling at 30mph.
- If you hit a cyclist or pedestrian at 35mph the force of the impact increases by more than a third than at 30mph.
- Reducing your speed by an average of 1mph will cut collision frequency by 5 per cent.
- On urban roads 76 per cent of cars will exceed the speed limit if the road is clear.
- It is not safer to drive faster at night. Casualty rates are double that during daylight hours due to the higher speeds because of less traffic, higher alcohol consumption, tiredness and darkness.
Stopping distances
Stopping distance is affected by a number of factors, including load, condition of the road surface, tyres, brakes, driver reactions and design and type of vehicle.
| Speed (mph) | Thinking distance | Braking distance | Total stopping distance | Total (feet) |
|---|---|---|---|---|
| 20 | 1.5 car lengths | 1.5 car lengths | 3 car lengths | 40 |
| 30 | 2.5 car lengths | 3.5 car lengths | 6 car lengths | 75 |
| 40 | 3 car lengths | 6 car lengths | 9 car lengths | 120 |
| 50 | 3.5 car lengths | 9.5 car lengths | 13 car lengths | 175 |
| 60 | 4.5 car lengths | 13.5 car lengths | 18 car lengths | 240 |
| 70 | 5 car lengths | 19 car lengths | 24 car lengths | 315 |
These figures assume dry weather and good tyres and an average family saloon. Naturally, stopping distances will vary according to weather conditions and some cars may perform in different ways.
There are many physical factors that can affect a car's stopping distance. What we want is for drivers to recognise that however good a driver they think they are and however good their car is, the difference between driving at 30 and driving a few mph over the limit, will lead to a much longer stopping distance that could lead to drastic consequences.
For more information on speed limits and how they are decided, see our dedicated web page.
This page was last updated on 9 May 2011
