Air quality in most areas of Australia is generally very good with specified pollutants occasionally failing to meet national guidelines. Photochemical smog is still an issue in some urban areas, indicated by high ozone levels. Pollutants are emitted to the air from various sources. The main stress on air quality in urban areas is a continued increase in the population, with car use rapidly rising (DEW, 2007).  Other sources include the combustion of wood and fossil fuels (such as coal, petrol and diesel), emissions of hydrocarbons from oil and gas refining, odours from industrial processes or intensive agriculture, and dust associated with mining and land clearing. When these emissions are released without precautions and during periods of poor wind movement or under conditions which cause smog, episodes of poor air quality may occur (DEC, 2007). Regional areas may experience poor air quality caused by raised levels of particulates from natural sources like bushfires and windblown dust, or from human sources such as industrial facilities and hazard reduction burns. In rural areas, insufficient air quality information exists as there is inadequate monitoring to identify areas of poor air quality (Manins, et.al, 2001). Some of the mechanisms in place to safeguard human and environmental health from airborne pollution include a series of national environment protection measures (NEPMs) related to ambient air quality, air toxics, National Pollutant Inventory data collection and diesel vehicle emissions. All Australian states and territories are required to report on their compliance against the national environment protection measures (EPA, 2006).