If the road ahead starts to look like this, pull over.

We've all seen the stats on driving while chemically challenged or talking on a cellphone, but there's another leading cause of car crashes that's often overlooked, especially at this time of the year when so many people undertake long holiday journeys: just plain tiredness.

And it seems to affect younger drivers more than it does older ones.

Whether that's because young people nod off more easily than adults or because teenage drivers underestimate just how tired you get sitting behind the wheel for 12 hours at a stretch is a moot point but, based on a recent survey by the American Automobile Association Foundation for Traffic Safety, one in seven licensed drivers aged 16-24 admitted to having nodded off at least once while driving in the past year as compared to one in 10 of all licensed drivers who confessed to falling asleep during the same period.


That ties in with 2010 National Highway Traffic Safety Administration crash data which estimates that young drivers aged 16-24 were more 78 percent more likely to be drowsy at the time of the crash as drivers aged 40-59. The 2010 NHTSA analysis showed that one in six deadly crashes involved a drowsy driver, making it one of the biggest causes of accidents.

AAA President Robert Darbelnet said: “Fatigue impairs safe driving, causing drivers to behave in ways similar to those who are intoxicated.

“This often overlooked crash risk is a serious threat to everybody's safety on the road.”

And here's a weird self-contradiction:

Eight out of ten people polled viewed drowsy drivers as a serious threat to their own personal safety but thirty percent of those same people admitted to driving in the past 30 days when they were so tired that they struggled to keep their eyes open.

AAA Foundation President Peter Kissinger commented: “Most drivers underestimate the risks associated with drowsy driving and overestimate their ability to deal with it - and that's a dangerous combination.”

Driving while drowsy results in slower reaction timed, impaired vision and lapses in judgment.

So if you find that you are:

Having trouble remembering the last kilometres or missing exits and traffic signs.

Having trouble keeping your eyes open and focused,

Yawning frequently or rubbing your eyes repeatedly,

Drifting from your lane or off the road,

Daydreaming or having wandering, disconnected thoughts.

Find (if possible) a safe place to pull off and get a few hours sleep - you can always text the people who are expecting you (even if it's the middle of the night) to tell them you'll be late.

This week is Drowsy Driving Prevention Week.

That’s a wake-up call (sorry, couldn't resist that) before you hit the long road to:

Get plenty of sleep (at least seven hours) the night before a long drive.

Avoid travelling at times you would normally be sleeping, such as the middle of the night.

Schedule a break every two hours or 200km.

Avoid heavy foods.

Travel with a companion and take turns driving.

Avoid medications that cause drowsiness or other impairment - especially hay-fever medication that may contain antihistamines.