Almost one in five drivers have dozed off behind the wheel, a shocking new report has revealed.

Of those who were nodding off, a worrying three in ten (29 per cent) have done so on the motorway doing speeds up to 70 miles per hour.

The report also found a quarter of men have fallen asleep while driving, making them almost twice as likely as women (13 per cent) to do so.

The Safety on Wheels Report, by Post Office Car Insurance, also looked at how often tiredness or a lack of concentration caused accidents.

Three in ten drivers have experienced an incident, from missing a pedestrian crossing to hitting another vehicle, because of a lapse in concentration.

Meanwhile, almost half (49 per cent) of UK drivers have driven while not concentrating.

Paul Havenhand, head of insurance at Post Office, said: 'When fatigue strikes, drivers should steer clear of the roads.

'Anything that hinders their ability to concentrate is dangerous and could result in a potentially fatal accident.

'There is no measurement for tired driving unlike driving while under the influence of alcohol, yet it could result in an equally dangerous accident.

'Drivers who are so tired they fall asleep while on the roads pose a serious risk to themselves and other road users.

'Roads can be hazardous enough as it is, without drivers putting themselves or others at risk by setting out when their concentration has been impaired.'

Drivers are advised to take a 15 minute break from driving every two hours.

However, a third (36 per cent) are so eager to reach their destination they will ignore feelings of fatigue.

What’s more, almost one in five (18 per cent) will drive for longer than four hours without a break - while six per cent carry on for up to six hours.

But when tiredness strikes, drivers do resort to a range of energy boosting measures.

Just over a quarter (27 per cent) opt for a quick caffeine fix and buy a cup of coffee while 17 per cent pull over until they feel alert again.

Mr Havenhand added: 'Sometimes it can be tempting to forge on ahead with a planned journey but it should never override the priority people place upon their safety.

'Drivers should ensure they plan ahead and rest before embarking on a long journey as well as taking regular breaks to recharge their batteries.

'In some circumstances, if they really do feel too tired to concentrate on the roads, they may want to consider an alternative method of transport.

'A momentary lapse in concentration might result in a scrape, or worse an accident, that could otherwise have been avoided.'

據(jù)英國《每日郵報》10月27日報道，英國一份報告稱，英國近1/5的汽車司機曾在開車時打瞌睡。

更糟糕的是，這些“瞌睡蟲司機”中又有3/10（29%）在高速公路上以每小時70英里(113公里)的速度行駛時打瞌睡。開車時睡著過的男司機達25%，幾乎為打瞌睡女司機的兩倍（13%）。

報告還研究了疲勞駕駛或注意力不集中時開車導致事故的頻率。研究顯示，近一半（49%）的英國司機在注意力不集中時開過車，因而經歷過事故的司機達3/10：有的沒注意到過路人，有的撞上其他車輛。

英國郵局保險負責人保羅說：“在犯困時，司機應該繞開道路。任何妨礙注意力的事情都很危險，有可能導致潛在的致命事故。疲勞駕駛和酒后駕駛不一樣，沒有測量標準，但有可能造成同樣危險的事故。”

司機每開2小時車后應當休息15分鐘。但1/3（36%）的司機因急于到達目的地而忽略了疲勞感。此外，近1/5（18%）的司機開車超過4小時不休息，還有6%的司機持續(xù)開車達6小時。

避免疲勞最常見的方法是喝杯咖啡，超過1/4（27%）的司機選擇買杯咖啡，利用咖啡因快速提神，只有17%的汽車司機靠邊停車休息。

保羅還說，“有時，按計劃前進很有誘惑力，但是絕對不該不優(yōu)先考慮安全。司機應該確保提前做好計劃，在開始長途旅行之前休息好，并在旅途中經常休息，恢復精力。有些時候，如果他們確實感覺太累，無法在路上集中注意力，就應該考慮換換交通工具，因為瞬間缺失注意力有可能導致本來能夠避免的刮蹭，甚至更嚴重的事故�！�