NSW annual air quality statement 2021

Air quality in New South Wales met national standards between 93% and 100% of the time across regions in 2021, an improvement compared with 2020.


This statement summarises the data collected from the New South Wales Air Quality Monitoring Network during 2021. It highlights air quality conditions at stations in metropolitan and regional centres as well as stations near industrial activities. Data are reported against national standards.

Stations in 'metropolitan and regional centres' include 3 stations near the Port of Newcastle – Carrington, Mayfield and Stockton – and 3 stations in larger population centres in the Upper Hunter – Aberdeen, Muswellbrook and Singleton (For more information, see Defining the Network).

Focus areas

The 2021 Statement presents 4 focus areas, including:

  • Two case studies examining air quality at monitoring stations nearby industrial activities in the Hunter Valley and at Stockton in the Port of Newcastle. While data from stations near pollution sources are not assessed for compliance with national standards, such comparisons are made available in this statement due to public interest.
  • A section outlining changes to the National Environment Protection (Ambient Air Quality) Measure (NEPM) standards for gaseous pollutants in 2021. It presents an analysis illustrating the impact of the national standards update compared to standards in effect during 2020.
  • A section highlighting NSW Government's recent achievements in air quality monitoring, reporting, forecasting and research.

Special note

NSW Annual Air Quality Statements report particle pollution as 24-hour average concentrations when comparing data with national air quality standards.

The NSW Government reports particle pollution online as one-hour averages, adopting a nationally consistent approach for reporting hourly PM2.5 data and related health advice.

Annual summary

  • New South Wales experienced improved air quality in 2021 compared to 2020, primarily due to cool and wet weather during the year reducing the frequency of exceptional events such as bushfires and dust storms.
  • Air quality varied regionally across New South Wales, meeting national standards for 93% of the year in the Newcastle Local region (with 24 days over the standards), to 100% of the time in other regions, including the Central Coast, Lake Macquarie, Mid North Coast and North West Slopes.
  • Fewer exceedance days were recorded in 2021 than in 2020, across all regions and all pollutants. The network recorded 53 days in 2021 with one or more criteria pollutant levels over national standards, compared with 118 days in 2020.
  • Air pollution levels exceeded national standards on 15% of days (53 days) in 2021 across the metropolitan and regional centres, compared to 32% of days (118 days) in 2020. The exceedances were for ozone, sulfur dioxide and particles as PM10 and PM2.5 (airborne particles less than or equal to 10 and 2.5 micrometres in diameter).
  • Particulates (PM10 and PM2.5) were the primary cause of days over national standards in 2021 (52 days). This was followed by ozone pollution on 5 days, and one day with a single 1-hour average sulfur dioxide (SO2) level over the national standard. Note that there were some days where 2 different pollutants were over the national standard.
  • Annual averages for particles (as PM10 and PM2.5) at the majority of locations were the lowest levels seen in the past 9 years.
  • All levels of nitrogen dioxide and carbon monoxide met national standards.

Daily average particle levels were above the national standards on fewer days in 2021 compared to 2020:

  • Daily average PM10 levels exceeded the national standard at one or more metropolitan and regional centres on 11% of days (40 days) in 2021, compared to 24% of days (87 days) in 2020.
  • Daily average PM2.5 levels exceeded the national standard at one or more metropolitan and regional centres on 6% of days (23 days) in 2021, compared to 16% of days (59 days) in 2020.

Annual average particle pollution levels decreased in 2021, compared to 2020:

  • Annual average PM10 levels for 2021 met the national standard in metropolitan and regional centres, except for Stockton at the Port of Newcastle. Stockton recorded the highest PM10 annual average with 30.1 µg/m3, similar to 2020, when it was the only station over the national standard with an annual average PM10 of 34.5 µg/m3.
  • Annual average PM2.5 levels did not meet the national standard of 8 µg/m3 at one monitoring station in 2021 (Stockton), compared with 14 stations in 2020. The highest PM2.5 annual average was 8.3 µg/m3 at Stockton at the Port of Newcastle. In 2020, the highest annual average was 11.8 µg/m3, at Goulburn in the Southern Tablelands.
  • Ozone levels exceeded (new) national standards at one or more metropolitan and regional centres on 5 days (1% of days) in 2021, compared to 9 days (2% of days) in 2020. Four of the 5 days occurred during hot summer conditions which are typical of ozone formation events.
  • Sulfur dioxide levels exceeded the (new) national standard on one occasion in 2021, compared with zero occasions in 2020. This occurred at Muswellbrook in the Upper Hunter on 4 February 2021.

Days with extremely poor air pollution levels are defined as those with pollution at levels exceeding twice the national standards for any pollutant.

Days with extreme air pollution in 2021 were all attributed to smoke from hazard reduction burns, resulting in elevated particle levels with daily PM10 levels exceeding 100 µg/m3 or daily PM2.5 levels exceeding 50 µg/m3.

  • There were 2 days with extremely poor PM10 levels at monitoring stations in metropolitan and regional centres in 2021, compared with 20 days in 2020.
  • For PM2.5, there were 9 days with extremely poor levels in 2021 compared with 19 days in 2020.

Defining the network

The NSW air quality monitoring network in 2021 comprised over 90 air quality monitoring stations. Over 50 stations used compliance methods to monitor air quality in areas of the State's highest populations, near industrial activities in the Upper Hunter and the Port of Newcastle, and at stations with special interest or research purposes. Over 35 stations, supported by the rural communities, used indicative instrumentation methods to monitor particles across the NSW rural air quality monitoring network.

Hourly updated data from the NSW Air Quality Monitoring Network is available for:

More local air quality reports are available in regular publications on our website.