Almost 600,000 Irish motorists are driving around on dodgy tyres leaving themselves open to the possibility of a serious accident and prosecution.

The alarming statistic was revealed by Paddy Murphy, general sales manager of Continental Tyres, at a new product launch in Dublin. Murphy said that with the recession indications were that motorists were now leaving it longer to change their tyres.

A survey by the Irish Tyre Industry Association some years ago showed that 50 per cent of drivers were leaving it too late to replace their tyres. "In other words the tyre tread was already below the legal limit of 1.6mm and if that study were to be repeated today the 50 per cent figure would rise substantially."

With 1.8 million vehicles on our roads this means that over 600,000 motorists are driving on defective tyres.

He said that the recession was making customers more cost conscious and many were taking the dangerous path of downgrading from premium tyres to budget tyres to save money in a difficult economic climate.

Welcoming the fact that from April tyres that do not have an 'E' rating to comply with international regulations will fail the NCT, Murphy said that there was still cause for concern that a tyre's speed rating was still not part of the NCT test.

He said it was known that motorists were frequently fitting tyres of a lower speed rating than that specified by the manufacturer and this was clearly dangerous.

Referring to the recent cold snap, he said that the case for cold weather tyres was strong given their superior braking performance in temperatures below 7°C. "For optimum performance and wear motorists should use standard tyres from April to September and cold weather tyres from October to March," he said.

Murphy was speaking at the launch of the ContiSportContact 5 P high performance tyre.