MORE than half of drivers risk falling asleep at the wheel, says a new survey.
And Huddersfield-based road safety charity Brake has blamed the Government for not doing enough to warn people of the dangers of driving while tired - especially on motorways.
The Transport Department recommends drivers to take a 15-minute rest every two hours to remain alert and safe on the motorway.
But under half of drivers follow this advice.
The survey, conducted by the Institute of Advanced Motorists, also shows 25% of drivers are regularly behind the wheel for more than four hours without a break.
Brake spokesman Simon Collister said the findings mirrored those of a similar study conducted by the charity.
He added: "The figures are very worrying - but the message does not seem to be getting through.
"Our survey showed a high percentage of drivers regularly had under five hours sleep.
"The Government has spent some money on advertising this problem and making drivers aware of the dangers. But it is nowhere near enough," said Mr Collister.
"We want the Government to carry out a high-profile campaign telling people not to drive when tired and how to prevent tiredness and stay safe.
"Drivers should pull off the road and have a caffeine drink and a rest."
It is estimated that about 23,000 smashes ever year on Britain's roads are caused by drivers falling asleep or being tired.