Stopping Distances - RoSPA's Pedestrian Injury Simulator

Facts : Drink-driving

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Driving after drinking alcohol is dangerous. It:

• Gives a false sense of confidence
• Slows reaction times
• Reduces co-ordination
• Reduce the ability to judge speed, time, and distance
• Reduces concentration
• Increases fatigue
• Impairs judgement

All of these effects greatly reduce a driver’s ability to drive safely, and puts them and others in serious danger.

The Law

It is a serious criminal offence to drive a motor vehicle if you are above the drink drive limit.

In England and Wales, the drink drive limit is 80mg alcohol per 100ml blood.

In Scotland, the drink drive limit is lower, at 50 mg alcohol per 100ml blood.

In Northern Ireland, the drink drive limit is 80mg alcohol per 100ml blood, but is due to be reduced to 50 mg for most drivers, but to 20 mg for young drivers and professional drivers.

The Police can breath test any driver who if to test any driver who:

  • they have reasonable cause to suspect has been driving or attempting to drive with alcohol in his body,
  • has committed a moving traffic offence, or
  • has been involved in an accident.

When somebody has been drinking alcohol, it is almost impossible for them to judge whether they are above or below the limit, and so the best advice is always to have none for the road.

Facts and Statistics about Drink Driving

On average, 5 people are killed in drink drive crashes every week on Britain’s roads. Often it is an innocent person who suffers, not the driver who is over the drink drive limit, but their passengers, people in other vehicles, pedestrians, motorcyclists and pedal cyclists.

Drink driving puts everyone at risk.

The level of drink driving has reduced substantially over the least few decades. In 1980, almost 1,500 people were killed, and nearly 8,000 people were seriously injured, in drink drive crashes. In 2013, this had fallen to 260 deaths and 1,100 serious injuries. However, this means that 5 people are killed and 21 seriously injured by drink drivers every week on our roads.

Other Impairments

Whilst drink driving is the most recognised form of driver impairment, driving after taking illegal drugs is also just as dangerous, and is also illegal. Drugs affect a driver’s behaviour, perception, and ability to control their vehicle safely.

Some medicines also impair a person’s ability to drive safely and drivers should always read the warning labels. If a medicine says 'may cause drowsiness', assume that it does.

The Simulator and Drink Driving

A car’s overall stopping distance from any speed is made up of the driver’s thinking distance (the distance the car travels between the point when the driver realises they need to brake and actually starting to brake) and their braking distance (the distance the car travels from the point when they driver starts to press the brake pedal and the vehicle coming to a complete stop).

Alcohol increases the time it takes drivers to process information – which increases their thinking and stopping distances. A drunk driver who spots a pedestrian would take extra vital moments before applying the brake.

This is shown by a large increase in the thinking distance in the simulator, but in the real world a drunk driver may also not press the brake as hard as a sober driver, which may also increase their braking distance. The extra time it takes a driver to press the brake, will mean that the vehicle is travelling at a faster speed when it hits the pedestrian, causing a more severe injury.

Figures taken from ‘Reported Road Casualties 2013, published by the Department for Transport’

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Produced with the support of the Department for Transport.
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