State Government of Victoria

Environment Protection Authority

Monitoring the environment

2009 Victorian air monitoring results


Victoria’s air quality in 2009 was generally good, with air quality objectives (other than for particles, visibility and ozone) typically met.

The major impacts on Victoria’s air quality in 2009 came from smoke from bushfires, planned burning and dust storms. These non-urban events led to a relatively high number of days when the particles standards were not met.

Accumulation of combustion particles from urban sources in calm, highly stable air also resulted in days when the particle standards were not met. The ozone standards were not met at three monitoring station on three days, under typical urban summer smog formation conditions. At other times, Victoria’s air was generally good.

Under climate change Victoria is predicted to become hotter and drier. As a result bushfires and dust storms are expected to become more frequent, affecting our air quality.

Compared to similar urban centres, Melbourne’s air quality remains relatively good, with little change over the last decade despite increasing pressures such as population growth.

Maintaining and improving Victoria’s air quality will be a challenge in the context of expected continued population growth and the impacts of climate change.

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Q&A on the 2009 Victorian air monitoring results + Expand all Collapse all

  • Where does EPA monitor?

    In 2009, EPA monitored air quality at 15 sites across Victoria, with:

    • 11 in metropolitan Melbourne
    • two in Geelong
    • two in the Latrobe Valley.
  • How do we assess air quality?

    Air quality is assessed against the national and/or state objectives and goals shown in the table below.

    Pollutant Averaging period Objective Goal (maximum allowable days not meeting the objective)
    Particles as PM10 1 day 50 μg/m3 5 days a year
    Particles as PM2.5 1 day 25 μg/m3 not applicable
    1 year 8 μg/m3 not applicable
    Visibility-reducing particles 1 hour 20 km 3 days a year
    Ozone 1 hour 0.10 ppm 1 day a year
    4 hours 0.08 ppm 1 day a year
    Carbon monoxide 8 hours 9.0 ppm 1 day a year
    Nitrogen dioxide  1 hour 0.12 ppm 1 day a year
    1 year 0.03 ppm none
    Sulfur dioxide 1 hour 0.20 ppm 1 day a year
    1 day 0.08 ppm 1 day a year
    1 year 0.02 ppm none
    Lead 1 year 0.50 μg/m3 none
  • What other factors affected air quality?

    Air quality in 2009 was affected by:

    • smoke from bushfires and planned burning (mainly for fuel reduction) in February and April 2009
    • windblown dust, including widespread dust storms during the warmer months of the year. Windblown dust is typically coarse and tends to impact PM10 more than visibility.
    • ozone formed under typical urban summer smog conditions
    • urban sources, predominantly motor vehicle and wood heater emissions accumulating in stable atmospheric conditions. These stable conditions tend to occur on calm, cold autumn/winter nights. These urban sources typically impact visibility more than PM10. When not properly managed, sources such as woodheaters can have a significant local impact.
  • What happened in my region?

    An assessment against Victoria’s air quality objectives and goals is shown in the 2009 air quality data.

    In Melbourne there were more days when the particle (PM10 and visibility) objectives were not met, compared with the previous year. Elevated PM10 levels occurred mainly on days affected by bushfires in February and planned burning (in April) and windborne dust (during the warmer months). Low visibility days were caused mainly by bushfires and planned burning and urban emissions (particularly from motor vehicles and wood heaters) that were trapped in calm, highly stable conditions.

    The four-hour ozone objective was exceeded at Point Cook in Melbourne on two days with conditions suitable for the generation of photochemical smog. The ozone goal was met at all other stations.

    The air quality objectives for nitrogen dioxide, carbon monoxide and sulfur dioxide were met on all days in 2009.

    Air toxics monitoring concluded at Campbellfield in January 2009. Levels were low and met the limits specified in the National Environment Protection Measure (NEPM) for Air Toxics.

    In Geelong, there were more days when the particle (PM10 and visibility) objectives were not met, compared with the previous year. As was observed in the previous three years, windblown dust was the major cause of high PM10 levels. Geelong had fewer days that did not meet the visibility objective than the Melbourne stations at Alphington and Mooroolbark. Days of poor visibility were caused mainly by bushfires, planned burning and urban emissions.

    The objectives for ozone, nitrogen dioxide, carbon monoxide and sulfur dioxide were all met.

    In the Latrobe Valley, there were more days when the particle (particularly PM10 and visibility) objectives were not met than in the previous year but less than in 2007. The main causes of high PM10 were smoke from bushfires (January to March) and windborne dust. Low visibility days were caused mainly by the accumulation of urban emissions, such as smoke from wood fires in the colder months.

    The objectives for ozone, nitrogen dioxide and sulfur dioxide were met on all days.

    Air toxics monitoring at Traralgon concluded in January 2008. Levels were low and met the limits specified in the Air Toxics NEPM.

    There was no monitoring in other rural regions in 2009.

  • What are the long-term trends?

    Air quality has changed very little in Melbourne over the past decade. Melbourne’s air quality is considered to be relatively good for a major metropolitan centre. Long term trend graphs are available with the 2009 air quality data.

    On a regional basis the NEPM goal has not been met in the Port Phillip region over the period 2003–09. The exceedances were attributed to fires (bushfires or planned burning) as the most frequent cause, followed by windborne dust and urban emissions. 2003, 2006 and 2009 were particularly affected by fires, with all stations in the Port Phillip region not meeting the goal.

    Further analysis of trends in compliance with the air quality goals is given in Air monitoring report 2009 — Compliance with the National Environment Protection (Ambient Air Quality) Measure (publication 1331).
  • How does Melbourne compare with other cities?

    Melbourne’s air quality is better than or comparable to interstate and international cities in countries of a similar level of development to Australia. Improvements are necessary, however, to preserve Melbourne’s relatively good air quality given increasing pressures from population and economic growth and a changing climate. A comparison is presented in EPA's report on Victoria’s air quality in 2006 (publication 1140).

Page last updated on 17 Sep 2014