NSW annual air quality statement 2021: PM10 particles

Daily average PM10 levels met the national standard in metropolitan areas, including Sydney Newcastle and the Illawarra, and regional centres on 89% of days in 2021, compared with 76% of days in 2020.

National standards for PM10

  • Annual average – 25 micrograms per cubic metre of air (25 µg/m3)
  • Daily average – 50 micrograms per cubic metre of air (50 µg/m3).

Annual average PM10 levels at all but one of 45 monitoring stations were below the national standard at all NSW monitoring stations in 2021. The exception was Stockton in Newcastle, which recorded an annual average of 30.1 µg/m3. This is similar to 2020, when only Stockton recorded an annual average PM10 over the national standard, with a level of 34.5 µg/m3. The Stockton monitoring site is significantly impacted by sea salt.

More information on the elevated levels recorded at Stockton can be found in the Stockton tab of Focus areas.

Apart from Stockton, levels in New South Wales in 2021 ranged from 6.9 µg/m3 at Narrabri in the North West Slopes to 21.0 µg/m3 at Carrington in Newcastle. In 2020, the equivalent lowest and second highest annual averages were 11.9 µg/m3 recorded at Coffs Harbour on the Mid North Coast and 24.2 µg/m3 recorded at Carrington, respectively. The annual averages of particles as PM10 at almost all locations were the lowest seen in the past 9 years.

More information about particle levels in the Hunter regions can be found in Focus areas – on the Hunter Valley and Stockton tabs.

Daily average PM10 levels exceeded the national standards at one or more of the 45 stations in metropolitan or regional population centres on 40 days in 2021. Excluding Stockton, there were 18 days with daily average PM10 levels over the national standards. This compares with 2020 when 87 exceedance days were recorded (55 excluding Stockton).

In 2021, 18 of the 45 monitoring stations recorded daily average PM10 levels over the national standards. Of these 18 stations, 15 are in the Sydney Greater Metropolitan Region (ranging from the Illawarra to Newcastle), one is in the Upper Hunter and two in the Riverina-Murray region. In 2020 all monitoring stations recorded levels over the standard except Lidcombe, Morisset and Penrith, all of which came online part-way through the year after the bushfire period in early 2020.

The maximum daily average PM10 level in 2021 was 125.2 µg/m3 recorded at Macquarie Park in East Sydney on 9 October 2021. These levels were significantly impacted by smoke from hazard reduction burns which took place nearby (less than 100m from the monitoring location).

The day with the largest number of stations exceeding the standard was 29 October. Five stations in metropolitan and regional centres, and an additional 6 diagnostic and small community stations in the Upper Hunter, were impacted due to a widespread dust storm on this day.

In Newcastle, sea salt spray results in elevated PM10 levels at Stockton. Local industrial sources also affect particle levels throughout the Hunter Valley. More information on the special purpose of industry-funded Hunter Valley monitoring networks is found in the Hunter Valley and Stockton tabs on the focus areas webpage.

Figure 1 Summary of PM10 observations in NSW metropolitan or regional population centres in 2021

Bar chart summary for PM10 measurements at the 45 stations in metropolitan or regional population centres. It shows for PM10, the maximum daily average, annual average and exceptional and non-exceptional event days. Exceedances of the 24-hour and yearly standards are shaded darker.

Note: Days exceeding standard are divided into exceptional and non-exceptional events. Exceptional events are those related to bushfires, hazard reduction burns and continental-scale dust storms. These are not counted towards the National Environment Protection Measure (NEPM) goal of 'no days above (i.e. exceeding) the particle standards in a year'.