When it rains, a film of water builds up on the roadway that significantly raises the risk of an accident due to...

Question

DentroTest · Accepted Answer

When it rains, the water on the roadway comes between the tread of the tire and the road surface, drastically reducing the coefficient of friction. If the tire cannot evacuate the water through its grooves (because of excess speed, tread wear or inadequate pressure), the vehicle may suffer aquaplaning or hydroplaning, completely losing steering and braking capacity. That is why the risk comes from the reduction or loss of grip between tires and asphalt. Overheating of the tires is not the cause: the water acts as a coolant and cools the wheels instead of heating them. Nor is the chemical composition or purity of the water the cause: the danger lies not in its chemical properties but in its physical effect of sliding and of interrupting the direct contact between tire and asphalt.

When it rains, a film of water builds up on the roadway that significantly raises the risk of an accident due to...

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