1.6mm in tread depth is enough, says Michelin

ERJ staff report (DS)

Berlin, Germany -- Michelin has carried out research in conjunction with Dresden Technical University which shows that relatively few accidents are caused by low tread depth. The team recorded accidents in Dresden and wheneveran acident was reported to th ePolice, arrived thre within 20 minutes to observe conditions.

In 69 percent of cases, the roads and weather were dry. In 27 percent of cases, there was some dampness or moisture present and in 4 percent of cases, there was show or ice present. In the 27 percent of incidents where moisture was detected, 0ver 86.5 percent iof incidents appeared to be on dry roads, but where tere was significant humidity. In 12.7 perent of cases, the raod was wet, but with no standing water and in only 0.8percent of the cases where moisture was present, were puddles or standing water observed.

The conclusion, said Michelin is that when ter eis standing water, drivers adapt their behaviour to become safer. However, the most significant finding was that a relatively large number of accidents occur when the condisitnos appear to be dry, but ter eis humidity in the air which translates to moisture in the contact patch between tyre and road. Drivers are not aware of this, so do not compensate by driving more safely.

Michelin therefore said it is developing tyres designs which ensure a progressive break-away when drivers approach the limit if grip and also is developing compounds which deliver improved grip in conditions which are apparently dry, but where moisture affects grip levels.