View the air quality summary map below showing the percentage of days when pollutant levels in different metropolitan and regional centres were below air quality standards (dark blue) or over the standards (light blue).
Exceedance days
There were 67 days in 2025 above national standards, while 36 days were recorded in 2024 (see the table below).
In 2025, every station across the NSW Air Quality Monitoring Network recorded at least one day above a national standard. Wagga Wagga North recorded the highest number of exceedance across stations in metropolitan and regional centres, with 22 days in 2025. This was largely driven by local dust and hazard reduction burning.
Particle pollution was the primary cause of poor air quality days in 2025:
- The PM10 standard was exceeded on 36 days (compared to 18 days in 2024).
- The PM2.5 standard was exceeded on 33 days (compared to 20 days in 2024).
This increase was primarily driven by local dust, hazard reduction burning and bushfire smoke.
Standards for gaseous pollutants were exceeded on 14 days in 2025:
- The ozone standard was exceeded on 12 days (compared to 3 days in 2024).
- The new one-hour sulfur dioxide standard was exceeded on 2 days. Although not in effect in 2024, this new standard would have been exceeded on one occasion in that year.
| Pollutant | Number of days over standard in 2025* | Number of days over standard in 2024* | Percentage of time standards were met in 2025 | Percentage of time standards were met in 2024 |
|---|---|---|---|---|
| Any pollutant exceeded | 67 | 36 | 81.6% | 90.2% |
| Particles as PM10 | 36 | 18 | 90.1% | 95.1% |
| Particles as PM2.5 | 33 | 20 | 91.0% | 94.5% |
| Ozone, O3 | 12 | 3 | 96.7% | 99.2% |
| **Sulfur dioxide, SO2 | 2 | 0 | 99.5% | 100% |
| Nitrogen dioxide, NO2 | 0 | 0 | 100% | 100% |
| Carbon monoxide, CO | 0 | 0 | 100% | 100% |
Notes:
*On any given day, levels may exceed standards for multiple pollutants or at one or more air quality monitoring stations. Also note that data are excluded for Stockton (Newcastle Local region) and data from Aberdeen, Merriwa, Singleton and Muswellbrook are included.
**From 1 January 2025, the one-hour standard for sulfur dioxide was lowered to 7.5 pphm. If the new standard were applied retrospectively to 2024 data, a sulfur dioxide exceedance in 2024 would have been recorded at Morisset. This would have resulted in 2024 sulfur dioxide data meeting this new standard 99.7% of the time compared with 100%. As a result, in 2024 pollutants would have then met standards 89.9% of the time compared with 90.2% and 37 days would have exceeded pollutant standards compared with 36 days.
Exceedance causes
Below, the source attribution for event days graph shows the sources identified as contributing to exceedances of PM10, PM2.5 and ozone air quality standards in each region.
Dust, wood heater smoke, hazard reduction burning and smoke from bushfires accounted for most exceedances of national particle standards, while photochemical smog and smoke from bushfires and hazard reduction burns accounted for ozone exceedances.
Notes:
On any given day, levels may have been over the standard for multiple pollutants at one or more air quality monitoring stations.
* Represents exceptional event days: that is, pollutant levels on these days were adversely affected by bushfires, jurisdiction-authorised hazard reduction burns or continental-scale dust storms in 2025.
^ Stockton is excluded from this analysis.
# Data from Aberdeen, Merriwa, Muswellbrook and Singleton only.
~ Days where both dust and smoke were present and contributed to a particle exceedance.
Ozone
The ozone standard was exceeded on 12 days at 17 stations across 9 regions in 2025. Three stations exceeded on more than one day, with Liverpool (South West Sydney) recording the most exceedances (4 days).
Nine of the 12 exceedance days were attributable to photochemical smog during heatwave events. These included 3 in January (6, 14 and 15 January) and 2 in March (14 and 15 March), with only 15 March recording exceedances at more than one station (3 in South West Sydney). Exceedances from 18 to 21 December were the most extensive ozone event of 2025, with 13 stations exceeding over the 4 days. These included 11 from Sydney as well as Wollongong (Illawarra) and Muswellbrook (Upper Hunter). On 21 December, 10 stations exceeded, all from Sydney.
Ozone exceedances on the 3 other days were due to smoke. Hazard reduction burning resulted in Macquarie Park (East Sydney) exceeding on 28 February with 8.0 pphm, the highest ozone level of 2025. Bushfire smoke caused exceedances at Wollongong on 6 December, and at Morisset and Wallsend (Lower Hunter) on 9 December.
Three ozone exceedance days occurred in 2024, affecting fewer stations and regions.
Particles
All 16 air quality regions recorded particle exceedances in 2025. Daily particle standards were exceeded on 59 days. PM10 was exceeded on 36 days, and PM2.5 on 33 days.
Dust was the primary cause of PM10 exceedances on 25 days in 2025. A widespread dust storm on 27 May resulted in the most extensive pollution event of 2025. Originating in eastern South Australia, PM10 exceedances were recorded at 33 of 46 stations in metropolitan and regional centres around New South Wales. The highest daily PM10 for 2025 (193.4 micrograms per cubic metre of air; µg/m3) was recorded on 27 May at Albury (Riverina–Murray). Exceedances on 24 days were due to local dust, which occurred at 13 stations in 2025.
Hazard reduction burning resulted in particle exceedances on 16 days in 2025, with dust also contributing to exceedances on 4 days. Bargo (South West Sydney) exceeded on 5 days, including 11 to 14 April, due to several large hazard reduction burns in Sydney. The highest daily PM2.5 (127.1 µg/m3) was recorded at Bargo on 11 April.
Smoke from domestic wood heaters contributed to exceedances of the PM2.5 daily standard on 12 days at 4 stations, all in June. Armidale (Northern Tablelands) and Gunnedah (North West Slopes) recorded the most exceedances, with 6 days and 5 days, respectively.
Bushfires caused particle exceedances on 11 days in 2025, with dust also contributing to one of those exceedances. Seventeen stations recorded particle exceedances from bushfires in December over 6 days, primarily from the Milsons Gully, Pacific Highway Bulahdelah and Nimbin Road Koolewong bushfires. The most widespread impact occurred on 6 December, when 13 stations exceeded particle standards across 8 regions, including Sydney, the Lower Hunter and surrounding air quality regions.
Sulfur dioxide
On 1 January 2025, the one-hour sulfur dioxide standard was reduced to 7.5 pphm. Morisset recorded 2 exceedances of this standard, on 27 August (8.3 pphm) and 16 September (8.5 pphm).
Although the new standard came into effect in 2025, this threshold was reached only once in 2024.