Sources of particulate pollution
Windblown dust and dust storms
Dust is generated from many different activities and sources. These include soil erosion, surface soil, unpaved roads, materials storage and handling and re-suspension of road dust from brakes and tyres. These all contribute to the particle levels in regional air.
During 1994–2009, the highest ever 24-hour average PM10 level in NSW was recorded at Newcastle on 23 September 2009 during a severe dust storm − 2,426.8 μg/m3. The highest PM10 level ever recorded at Albury (940.2 μg/m3) and Wagga Wagga (970.0 μg/m3) was due to a dust storm on 19 March 2003.
Following the severe dust storms throughout NSW in 2009, OEH launched a DustWatch website. The site provides valuable information to scientists, farmers, land managers and the broader community about dust conditions and wind erosion through regular reports on dust activity.
DustWatch does not aim to report on air quality. Instead, the program aims to:
- report on the extent and severity of wind erosion by measuring dust concentration and observing visibility, and
- raise awareness of the effects of wind erosion on the landscape and the impacts of dust on the community and the environment.
With changes to weather patterns predicted to occur across NSW, it is likely that some areas will experience warmer temperatures and lower rainfall. This will most likely contribute to more dust storms.
Bushfires in Murramarang National Park, 2010
Bushfire smoke contains a complex mixture of gases and fine particles produced when wood and other organic matter is burnt.
Bushfire smoke can have a major impact on air quality in regional NSW. A study by CSIRO in 2008 - Particles, ozone and air toxic levels in rural communities during prescribed burning seasons - found that during bushfires, the ’air quality of impacted rural towns is almost 100% worse than the worst months in Sydney’.
With changes to weather patterns predicted to occur across NSW, it is likely there will be an increase in bushfire frequency and/or duration. Particle pollution is likely to increase if there are more fire days.
Bushfire hazard reduction burning
Low-intensity bushfire hazard reduction burning refers to the practice of removing excess fuel loading in the bush (e.g. ground litter) using fire. It aims to minimise the potential impacts of a bushfire on life, property and the environment.
Hazard reduction burning is strategically planned to minimise the potential impact of smoke on public health and amenity.
The NSW Rural Fire Service's hazard reduction burns page shows when and where burns will be conducted by NSW land managers.
Solid fuel heaters and woodstoves
Excessive smoke from incorrectly installed or operated wood heaters is a major contributor to air pollution. It is a major source of particle pollution in regional NSW during the cooler months. Pollutants in the smoke include:
- gases, such as carbon monoxide
- organic compounds, including air toxics
- fine particles, formed when unburnt gases cool as they go up the chimney − in the air, these can be seen as white smoke.
Agricultural stubble burning
Stubble is the plant residue left in a paddock after harvest, including the stem, leaf and glumes of cereals. Stubble is burnt for a variety of reasons including reducing the risk of disease carryover and pests to the next crop, reducing weed seed banks and reducing stubble loads to allow easier sowing the following season.
Crops subject to agricultural burning include:
- cereals (e.g. wheat, barley)
- legumes (e.g. lupins)
- oilseeds (e.g. canola).
This practice can cause significant localised air pollution.
Further information on agricultural stubble burning is provided in the local government air quality toolkit.
Page last updated: 18 June 2013