A recent survey has revealed that one in 10 motorists would fail their driving test if they were to sit it again, because of poor eyesight. This will not come as news to anyone who regularly uses the British Road Network. After all, though simple eye tests are a standard procedure at the driving test centre, there's still no compulsory re-test of a driver's sight until the age of 70.

Many motorists are unaware of their fading vision, and therefore don't realise they are unfit to drive. Furthermore, nearly half of all drivers who wear glasses or contact lenses admit they don't wear them at the wheel.

As the number of drivers on our roads continues to increase, the potential for accidents is also set to rise and, with that in mind, experts recommend the following advice: We are required by law to ensure we can read a number plate from a distance of 20.5 metres (67 feet).

The distance requirement for the eyesight test with the new-style number plate is 20 metres. New-style number plates were introduced on 1 September 2001 and are easily identifiable because they start with two letters ie AB51 ABC. The Drivers Medical Branch of the DVLA therefore advises that we have our eyes professionally tested every two years.

Forgetful Every day, tens of thousands of shortsighted people take to our roads, having forgotten (or chosen) not to wear their glasses. The majority do not realise that in doing so, they are breaking the law. If that's you, then try to always carry a spare pair in the car. After all, in some European countries, this is a legal requirement.

Contacts If you wear contact lenses, the chances are your eyes will grow tired more quickly on a long journey, so it would be worth switching to a pair of glasses, until reaching your destination.

Fashion Some spectacles are better than others for driving. The trendy models with rimless designs, and those with particularly thin rims, are actually the most suitable, as they allow greater all-round vision.

Glare To reduce glare from the sun, and from the lights from on-coming traffic, anti-reflection coatings can be applied to any lenses. This will help you to see more clearly, especially when driving at night.

The Code The Highway Code states that tinted glasses and tinted motorcycle helmet visors must never be worn after dark. Nor should they be worn in conditions of poor visibility such as heavy rain, fog and during snowfall.

Medicine Like alcohol, some medicines not only impair vision, but can also slow down reaction times when driving. It's therefore worth checking with your doctor whether a prescription is safe before taking to the wheel.

The major problem is that in the majority of cases, motorists don't even realise their eye sight is posing a danger, not just to themselves, but to other road-users. If you find yourself suffering from headaches, or feeling particularly tired when driving, the best thing you can do is visit an optician.

It could save your life.