THE PREDICTED IMPACT OF REVISED AUSTRALIAN CAR DESIGN RULES ON MELBOURNE AIR-QUALITY TRENDS

The emission of atmospheric pollutants such as carbon monoxide (CO), o xides of nitrogen (NOx) and hydrocarbons (HC) from Australian motor ve hicles depends on the performance of the emission control devices fitt ed to them. The total emission of these atmospheric pollutants nas cal culated for Melbourne, assuming deterioration rates for the control eq uipment such that vehicles comply with Australian Design Rules for fiv e years. There is an initial decline in total emissions of CO and HC, but by the year 2011 the expected increase in total vehicle kilometres (VKT) means that the output of all pollutants to the airshed will inc rease with time. Significant decreases in atmospheric emissions are on ly possible by stricter emission controls.