§ Mrs. Ann Taylorto ask the Secretary of State for the Environment what proportion of the black smoke emitted by road transport reported in his Department's statistical digest No. 12, page 14, is estimated to come from diesel vehicles; what are the relative contributions of diesel smoke and smoke from domestic sources to overall smoke emissions in smoke control areas; and what information he has about the relative soiling effects of diesel smoke in comparison with coal smoke.
§ Mr. TrippierIt is estimated that 184,000 tonnes of black smoke was emitted by road transport in 1988 and that 92 per cent. of emissions from transport came from diesel vehicles.
Information is not available for the relative soiling effects of diesel smoke in comparison with coal smoke, or for the relative contributions of diesel smoke and smoke from domestic sources to overall smoke emissions in smoke control areas. Emissions of black smoke from domestic sources for the United Kingdom as a whole have fallen by approximately 71 per cent. since 1970, while emissions from diesel vehicles have risen by 86 per cent. over the same period.