SIR – I can’t imagine who in their right mind set the UK limit for tyre tread at 1.6mm as this standard is difficult to measure accurately when it represents just 64,000th of an inch!

The general European tread depth of 3mm is far more logical and safer. They obviously understand better that brakes stop the wheels turning but tyres stop the vehicle moving.

As a former international transporter, I always renewed my tyres when they got down to that level so as not to be caught out by the authorities abroad.

Although the Euro standard brought many thousands of second-hand tyres to the UK, particularly from Germany, the only problem with second-hand ones is you don’t know what they have been used for or if they were on a car in an accident.

Surely the best way would be to make it a round figure, eg, at least 2mm, then everyone would know where they stood and today there are plenty of budget-priced new tyres about to keep legal on.

DS Boyes, Upper Rodley Lane, Leeds