This proposed increase for tread depth on tyres, at almost twice the current legal limit, is based upon accident figures and results from a survey by the Ergonomics and Safety Research Institute of Loughborough University. Looking at how this might affect safety, the Institute undertook an estimate of the benefits and estimated that the number of pedestrian casualties struck by cars would benefit from an increase in the minimum tread depth for tyres.

A similar study into the safety aspects of tread depth on tyres was also undertaken by MIRA and both bodies have published the results of their studies. The overriding conclusion from both these bodies is that increasing the minimum tread depth would result in fewer casualties. In fact further studies have been carried out to estimate a cost per casualty and this enabled MIRA to calculate the savings resulting from a 3.5mm minimum tread depth for tyres.

These figures make interesting reading for all those concerned with tyres and road safety. However at this point in time it is not known at whether or not the Government will decide to consider changes in the law regarding tread depth. In fact the Government generally undertakes a detailed impact assessment when deciding to consider changes to the law. Whatever the outcome, tread depth on tyres is likely to remain high on the road safety agenda.

The implications of such a change to the law on tyres upon the average motorist is a matter of speculation at this point and no related studies have as yet been carried out in order to canvass, log and analyse their views. However tyres with a 3mm tread depth are likely to be viewed as only lightly worn by many and there is no way of knowing if a consumer backlash could result, possibly leading to a further move towards the fitting part worn tyres on economic grounds.