Australia State of the Environment Report 2001 (Theme Report)
Lead Author: Dr Peter Manins, Environmental Consulting and Research Unit, CSIRO Atmospheric Research, Authors
Published by CSIRO on behalf of the Department of the Environment and Heritage, 2001
ISBN 0 643 06746 9
Urban Air Quality (continued)
Indicators of the condition of air quality (continued)
Nitrogen dioxide in urban areas [A Indicator 3.4]
The NEPM Standards for nitrogen dioxide are 0.12 ppm averaged over one hour, and 0.03 ppm averaged over one year. The only location to have exceedences is Sydney, which shows exceedences of the one-hour standard, but these occur on only one day per year (Figure 99).
Figure 99: Highest one-hour nitrogen dioxide concentrations for selected Australian cities.
Source: State environmental authorities
High concentrations of nitrogen dioxide and sulfur dioxide indicate large-scale, uncontrolled, industrial emissions. That nitrogen dioxide is not a problem in urban Australia, except possibly in Sydney, confirms the adequacy of the existing controls on industrial stack emissions. Nitrogen dioxide is also formed from the NOx emissions from motor vehicles so that it is to be hoped that the ADR37/01 limits on NOx emissions will reduce the exceedences in Sydney.