HC Deb 04 August 1976 vol 916 cc867-8W
29. Mr. Ronald Atkins

asked the Secretary of State for the Environment whether total road traffic as referred to in 3.12 of the consultation document comprises all traffic, including passenger, freight and local distribution services, that use roads; and if this traffic is calculated by weight or by number of vehicles in his percentage comparisons with rail traffic.

Dr. Gilbert

The total road traffic referred to is traffic from all vehicles on all roads. The unit of measurement is passenger car kilometres. Heavy goods vehicles are counted as equivalent to three cars. On this basis heavy goods vehicles account for 21 per cent. of traffic even though they are responsible for only 8 per cent. of vehicle kilometres. The 50 per cent. increase in rail freight referred to is an increase in tonne kilometres.