Vince Yearley: 'Tiredness kills', the signs say. Dead right, too

There's an old joke about the man who was asked how he wanted to die. "Quietly, in my sleep, like my dad did. Not like all his passengers, screaming behind him."

Go on, admit it. Have you ever driven knowing you were tired? Perhaps at the end of a long weekend away? Or after you've been to a load of meetings and all you want to do is get home and crash out in front of the telly?

I ask because many of the UK's 32 million licensed drivers do it. These are the same motorists who refuse point blank to take a drink when they are driving. And illegal drugs? Never.

A recent survey by my colleagues at the Institute of Advanced Motorists showed that motorists in all vehicles are too often prepared to ignore the effects of tiredness and drive on. Professional drivers have built-in safety: tachographs, for example, to stop them going on too long without a proper break. But the average car-driver has no such safeguards.

So why do we ignore driver fatigue – the so-called silent killer? Perhaps it doesn't occur to us that something's wrong until it's too late. Fatigue is a natural phenomenon and one we all learn to accept. We think we can handle it. Unlike drink and drugs (including over-the-counter medicines that can cause drowsiness), we are more prepared to ignore that doziness because it is so familiar.

But a tired motorist, tackling the mentally and physically demanding task that driving is these days, is wrestling with a potential killer. Even a quiet, straight motorway at 1am after a party can be lethal.

In fact, fatigue operates in much the same way as alcohol at the wheel. Drivers who are slightly tired will not drive as well, or as safely. As tiredness increases, mental and physical performance fall off until, in effect, the driver falls asleep.

Experts claim that 20 per cent of motorway crashes are thought to be related to driver fatigue, although the statistics here don't help much. The police currently have no way to measure impairment at the roadside, the way a breathalyser does.

At the Pan London Road Safety Forum event held last week by Transport for London, a Met Police spokesman said the penalties for drug-driving are as a severe as for drink-driving. But the "drugalyser" has yet to be approved – and there's nothing to help an officer tell if a driver is too tired to carry on. Drivers who are tired usually won't admit it. Those who crash are either killed or often too badly injured to recall the events that led to the collision.

The IAM says that fatigue will never be completely avoidable, but there are simple steps drivers can take to minimise the risk. Start fresh, and get plenty of rest before a long journey. If you're feeling tired or unwell already, make another journey plan. Reduce fatigue by wearing comfortable, loose clothing. Adjust the seat to a comfortable, upright position. Set the climate control to a cool – but not cold – temperature.

Then, stay fresh. Build in regular breaks– every 90 minutes to two hours, depending on driving conditions. Get out the car and walk around; check your voicemail and drink a caffeine-rich drink.

If you start to feel tired, act quickly; don't try to drive through fatigue. Don't turn up the volume on the stereo. Don't open the window or turn the aircon to the coldest setting in the hope that these actions will keep you awake – they won't.

Find a safe place to stop, take a nap (20 minutes at least), and get some fresh air and exercise. If you feel more awake, continue – but bear in mind that you will have to stop again soon. If you still feel tired, sleep until you feel fresh enough to continue.

That nap could be the one that saves your life.

Vince Yearley is head of media at IAM Motoring Trust

motoring@independent.co.uk