How you could be just as dangerous behind the wheel as drink drivers without realising

WE all know that drink driving is a big no no.

But did you know that driving while tired could be as dangerous as drink driving?

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Tiredness contributes to about four per cent of fatal road crashes[/caption]

A new study has found those who have less than five hours of sleep a night are just as likely to have a vehicle crash as those over the legal limit for alcohol.

Tiredness contributes to about four per cent of fatal road crashes and two per cent of all collisions in Britain, according to road safety charity Brake.

However, it is likely that the true figures are far higher because fatigue is hard to spot and, unlike alcohol and drugs, police can’t test for tiredness.

The Australian scientists found having less than four to five hours of sleep in the previous 24 hours doubles the risk of a vehicle crash.

This is the same crash risk seen when drivers have a blood alcohol concentration of 0.05 per cent – which equates to around two drinks.

In Scotland, a blood alcohol level above 0.05 per cent is considered over the legal limit.

While in England, Wales and Northern Ireland, anything above 0.08 per cent is over the legal limit.

Not only this, but a driver’s risk of a crash significantly increases with each hour of sleep lost the night before. 

Previous studies suggest that when a driver had between zero and four hours of sleep the previous night, they may be up to 15 times more likely to have a crash.

The evidence suggests Governments could require drivers to have a certain amount of sleep before getting behind the wheel, study author Doctor Madeline Sprajcer, or CQUniversity Australia, wrote in The Conversation.

 “If we were to align with the degree of risk considered acceptable for intoxication, we may consider requiring a minimum of four to five hours of sleep prior to driving,” Dr Madeline explained.

However, for the most part, drinking alcohol is something individuals choose to do – how much sleep someone gets is not, she said.

For example, new parents, shift workers and people with sleep disorders can’t always get more sleep.

The study was published in Nature and Science of Sleep.