Air quality in ACT

How bad is the air quality in ACT?

The Australian Capital Territory (ACT) is the country’s federal territory housing the Australian capital city of Canberra, along with some nearby townships. Landlocked as an enclave within the state of New South Wales, the capital territory is established between Australia’s two most populated cities, Sydney and Melbourne, and is home to the country’s political establishment. ACT’s regional surroundings of forest, farmland and nature reserves has earned the region the nickname of “Bush capital”.

ACT’s air quality is generally at a healthy level most of the year round, in comparison with other global locations; however, similarly to much of Australia’s air quality, the territory is vulnerable to experiencing some extreme air pollution episodes, most often caused by dust storms and wildfires. The main pollutants of concern for people’s health within ACT, are particulate matter: microscopic airborne particles less than 2.5 or 10 microns in diameter (abbreviated as PM2.5 or PM10 respectively). These particles are particularly hazardous since their tiny size enables them to travel deep into the human system via the lungs, with PM2.5 even able to travel further into the bloodstream, causing a range of health effects. PM can be generated from human-based activities, such as combustion of fuel in vehicles and industry, as well as natural causes such as smoke from bushfires, and dust storms.

During 2019, Canberra – which represents all monitored air quality data within the ACT – ranked as Australia’s 3rd most polluted location nationally for PM2.5 pollution, of a list of 95 measured cities included in IQAir’s 2019 World Air Quality Report.¹ The capital city averaged an annual concentration of 15 μg/m³, which exceeds Australia’s national annual air quality standard for PM2.5 of 8 μg/m³, almost twofold. It also exceeds the World Health Organisation (WHO)’s slightly less stringent international PM2.5 standard, which is an annual mean concentration of 10 μg/m³. Canberra’s air quality fared better than only two other locations within Australia, the cities of Armidale (averaging 23 μg/m³) and Tamworth (15.2 μg/m³). This highly polluted position in comparison with other Australian locations may be linked to the particularly devastating bushfires that affected ACT during the country’s summer of 2019-2020. While Canberra’s monthly average PM2.5 levels ranged between a generally lower 7.8 - 12.6 μg/m³ from January to November in 2019, December’s average value soared up to 74.1 μg/m³, indicating a severe and persistent level of particle pollution throughout the month, which helped to bring up Canberra’s annual average overall.

Real-time air quality information can be found in the dynamic Australian Capital Territory air quality map at the top of this page, along with live wildfire updates. This information can be followed anytime using the IQAir AirVisual air pollution app, along with a 7-day ACT air quality forecast.

How does the ACT’s air quality compare globally?

However, while Canberra may appear to be more polluted within the context of the generally clean Australia, global context sheds some additional light. For example, Paris air quality experienced a similar level of pollution during 2019, averaging 14.7 μg/m³, and Canberra ranked as a cleaner capital city than Manila’s air pollution (18.2 μg/m³) and Singapore air quality (19 μg/m³). Canberra remained, however, more polluted than London (12 μg/m³) and New York (7 μg/m³) during 2019.

What are the health impacts of ACT air pollution?

Exposure to air pollution can cause a range of short- and long-term health effects. Short periods of exposure can aggravate existing conditions such as asthma, while also causing irritation to the eyes, nose and throat. Long-term effects of exposure to air pollution can include increased risk of developing respiratory or cardiovascular disease, such as lung cancer, chronic obstructive pulmonary diseases (COPD), stroke, and coronary heart disease. Exposure to air pollution can also increase risk of premature mortality and death. A 2016 study conducted by the Australian Institute of Health and Welfare (AIHW) in Canberra, analysed the Australian burden of disease from air pollution in 2011. The study found that of the total number of Australian deaths linked to air pollution, the majority of these were caused via coronary heart disease (70%), followed by stroke (26%), then lung cancer and COPD.²

What are the main sources of pollution in ACT?

The major contributors to particle pollution within the Australian Capital Territory are smoke from wood heaters and bushfires, vehicle emissions and windblown dust. Other pollutants such as carbon monoxide and nitrogen dioxide, are primarily emitted from motor vehicles. Conversely, ozone, which is an example of a photochemical oxidant, is not directly emitted from any single source, but rather is a secondary pollutant: this means that it is formed through the chemical reactions of other pollutants in the atmosphere. Ozone is formed when nitrogen oxides react with other air pollutants known as reactive organic compounds (ROCs), in the presence of sunlight; accordingly, high ground-level ozone concentrations are most likely during sunny and hot conditions.³

Are there still fires in Australian Capital Territory?

ACT, like the rest of Australia, is prone to experience the effects of bushfires during Australia’s hotter months. While fires tend to affect various parts of Australia at different times in the year due to seasonal changes, with northern Australia experiencing higher fire risk earlier than southern Australia, ACT’s prime time for dangerous fire conditions occurs after the dry winter and spring, from spring into mid-summer.⁴ During 2019-2020, Australia as whole experienced some of the worst wildfires on record, known colloquially as the “black summer”. These fires were particularly devastating, due to months of prolonged drought, limited rainfall, and record-breaking temperatures. While New South Wales was worst affected by fires of any state in the country, ACT, nestled within NSW, also experienced severe impacts from the fires.

On New Year’s Day 2020 (1st January), Canberra awoke to some of its worst air quality on record. The smoke coming from nearby bushfires was intensified due to a temperature inversion: a weather event where a layer of warm air sits above a layer of cooler air at ground-level, when usually the reverse arrangement is true. The warm layer of air “traps” the air below, including any air pollution within it; therefore temperature inversions can often worsen and prolong air pollution episodes, by preventing the polluted air to escape a given area. The New Year’s Day air pollution was the worst since monitoring began 15 years prior in ACT, with shocking Australian AQI readings of 3,463 (when any Australian AQI reading above 200 represents “hazardous” air quality).⁵ The poor air quality had caused at least 12 people to be admitted to Canberra hospital with smoke-related illnesses within the same 24 hours.⁵

While Canberra and the Australian Capital Territory were experiencing severe smoke blown in from surrounding areas until that point, ACT also experienced its own “black summer” bushfires shortly after the New Year’s Day episode. ACT’s first major bushfire began on 16 January next to Canberra Airport, which was brought under control within a couple of hours; a second fire broke out again the following day nearby, which again was brought under control by fire fighting teams relatively quickly. However, some flights were cancelled as a consequence of these, and some vehicles were reportedly also damaged in the airport’s car park. Another fire broke out on 27 January 2020, from the Orroral Valley through the Namadgi National Park, travelling east and north-east towards Canberra, growing quickly.⁶ Hot conditions and an abundance of dry material to feed fuel to the fire made this blaze difficult to control, and it grew into the worst fire that ACT has experienced since the historically awful Canberra wildfires of 2003, which had killed 4 people, injured 435 and caused 5000 people to be evacuated.⁷ This Orroral Valley fire was ignited accidentally by a military helicopter during a firefighting operation in the area, when heat from the helicopter’s landing light started an unintended grassfire below it during a landing for reconnaissance.⁶ The fire was eventually officially announced as fully contained a month later, on 27 February 2020, after 40 days of continuous operations by the ACT Emergency Services Agency.⁸

What is ACT doing about air pollution?

The Australian Capital Territory’s Health department runs a network of air quality monitoring stations around the territory. These are located at Civic (Canberra’s city center or central business district), Florey (a residential suburb), and Monash (a suburb in the district of Tuggeranong). The monitoring sensors measure a range of 5 key pollutants: carbon monoxide (CO), nitrogen dioxide (NO₂), ozone (O₃), PM10 and PM2.5. The territory does not monitor sulphur dioxide (SO₂) concentrations, due to a lack of heavy industry making this of less concern. While the ACT also used to previously monitor airborne lead, this was stopped in July 2002 following the phase out of leaded fuel in January 2002.⁹ Through monitoring air pollutants, ACT is responsible as a state to try to ensure that its state-wide pollution levels do not exceed the Australian air quality standards, known as the National Environment Protection Measure for Ambient Air (NEPM) standards.

Does ACT use an air quality index?

The Australian Capital Territory reports its air quality measurements to the public using an ACT Air Quality Index, which follows the broader Australian air quality index system. The ACT AQI system is intended to convey pollutant measurements, which can be complex, in a simplified way that clearly indicates a level of health hazard, and whether Canberrans should act to protect their health against air pollution. The AQI is calculated for each pollutant measured at a given location, expressed as a percentage of the NEPM standard for that pollutant. For example, an AQI level of 100 indicates that a pollutant is at the maximum allowable amount within the standard (100%); an AQI of 200 indicates a twofold exceedance. Whichever pollutant has the highest AQI, will dictate the overall AQI for that location. The ACT AQI scale is color-coded, from 0-33, “Very Good” (blue), up to 200+, “Hazardous” (red).

+ Article resources

[1] IQAir. “2019 World Air Quality Report”. IQAir website, March 18, 2020.
[2] Australian Institute of Health & Welfare (AIHW). “Australian Burden of Disease Study: impacts and causes of illness and death in Australia 2011”. Australian government website, 2016.
[3] ACT Government. “Air pollutants and sources”. ACT Government website, September 3, 2019.
[4] Australian Government Bureau of Meteorology. “Bushfire weather”. Bureau of Meterology website, n.d.
[5] Graham Readfearn. “Canberra experiences worst air quality on record as bushfire smoke from south coast sets in”. The Guardian, January 1, 2020.
[6] Australian Institute for Disaster Resilience. “Australian Capital Territory, January – February 2020: Bushfires – Black Summer”. Australian Disaster Resilience Knowledge Hub, n.d.
[7] Australian Institute for Disaster Resilience. “Canberra Bushfire 2003”. Australian Disaster Resilience Knowledge Hub, n.d.
[8] ACT Government. “Information update: Orroral Valley fire declared out”. ACT Government Emergency Services Agency website, February 27, 2020.
[9] ACT Government. “Air pollutants and sources”. ACT Government website, September 3, 2019.