In 1974 the American President set the maximum speed limit for road users at 55mph.

This was to save large amounts of oil based fuel, owing to disruption of supplies.

Of course this would reduce, proportionally,the air pollution that this fuel would have produced.

If our present road speed limits were properly observed, there would also be a large reduction of air pollution caused by vehicle road users.

Road pollution of the air around us, is made up petrol and diesel fumes, brakepad dust, tyre rubber particles, engine noise and road noise.

If driven steadily, the faster a vehicle travels increases all of these propotionally.

The faster the acceleration, the more excessive the fuel, noise, and rubber pollution is.

The faster the deceleration, the more noise, brake dust, and tyre rubber pollution is.

Travelling, and increasing speed above the speed limit, illegally, creates increasing amounts of all this pollution, and also more collisions, and fatal accidents.

To better protect people from as much air pollution as we can, while they go about their daily lives, we need to start here.

Harry Potts, via email