Builders, electricians and plumbers are being warned off skimping on replacement tires in an attempt to cut vehicle running costs.

According to tire and maintenance provider ATS Euromaster, while the retailing part-worn tires is not illegal in the UK, there is no governance over the quality of the tires and whether they have gone through any internal structural trauma even if they appear outwardly good value.

An investigation by tire safety charity TyreSafe with the UK’s Trading Standards body found that 94% of part-worn retailers were selling tires illegally, and 63% of the tires were unsafe to return to the roads. Estimates suggest that some 5.5 million part-worn tires are retailed each year.

Lois Harvey, category manager at ATS Euromaster, commented: “We have recently seen plenty of part-worn tire traders popping up, no doubt seeing the chance to offer apparent value as the cost-of-living crisis continues to grip the UK. But you have no guarantee over the veracity of the tires being retailed and whether they are safe. It is a false economy for the trades and small businesses to think they are getting a bargain.

“I would also advise that they need to consider their duty of care to other motorists and road users. Under the Health & Safety at Work Act 1974, as a tradesperson, whether self-employed or as a one-person limited company, you are responsible for the safety of your vehicle at work. If you are found guilty of a breach - such as causing an accident where part-worn tires were identified as the culprit - the fines can be unlimited, and there is also the possibility of imprisonment.”

ATS Euromaster said many part-worn tires were sourced from Germany where compulsory winter tires must have a minimum tread of 3mm. Others sources were from salvage or scrap merchants that deal with old cars and write-offs and sell the tires to make extra cash.