And, while more than half of motorists claim to have checked their tyre pressures in the last month, 49% of drivers do not know that an underinflated tyre can dramatically affect a car’s stopping distance.

Bridgestone UK is behind the survey, as part of a new campaign to use its network of 170 First Stop tyre dealerships to offer every driver in the country a free tyre health check and cut down on the 34,351 deaths and serious injuries on U.K. roads each year. The company has recently joined forces with the RAC Foundation and FIA Foundation to promote the Think Before You Drive campaign, encouraging all drivers to check their tyres in an effort to reduce accidents.

“Tyres are the only contact our cars have with the road,” said John McNaught, managing director of Bridgestone UK. “Our survey has illustrated that, while people believe they are driving around safely, the truth is that many motorists are still unsure as to how much air should be in their tyres and how much tread should be on them.”

The survey showed that women are the worst offenders, with only 46 per cent having checked their tyre tread depth in the last month and only 23% actually knowing the safe legal tread depth limit is 1.6mm.

Teenagers also fared badly, with almost 60% of 17 to 24 year olds admitting they do not know how much tread needs to be on their tyres to keep them safe. And, while drivers over 55 claim to be the most vigilant, with a massive 85% insisting they have never driven with a tyre even slightly flat or remotely unsafe, an amazing 65% admitted they did not know how much tread they should have on their tyres.

“While our primary concern is safety,” said McNaught, “it’s also worth noting that for each tyre that is below the legal tread limit, motorists can be fined £2,500 and have three penalty points added to their licences. So, anyone who has four tyres below the limit could potentially be fined £10,000 and be banned from driving because of the 12 points.”