The predicted impact of revised Australian car design rules on Melbourne air quality trends

The emission of atmospheric pollutants such as carbon monoxide (CO), oxides of nitrogen (NOx) and hydrocarbons (HC) from Australian motor vehicles depends on the performance of the emission control devices fitted to them. The total emission of these atmospheric pollutants was calculated for Melbourne, assuming deterioration rates for the control equipment such that vehicles comply with Australian Design Rules for five 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 increase with time. Significant decreases in atmospheric emissions are only possible by stricter emission controls.