State Government
The state government is concerned about gathering information on urban air quality to inform people and use it as a basis for responses on air releated issues. This government also created "action for air", an air quality management plan in which a broadly based forum is conducted every three years to encourage public input on the topic of air quality tendancies and stratedgies
This is the form of governmnet who would go to if you wanted to find background information on urban air quality.
http://www.environment.nsw.gov.au/air/
Federal Government
While the state governmnet looks into air quality and tries to create awareness about it, the Federal Government looks to create policies and programmes attempting to disminish air pollution. The Australian Government's focus is on the sectors that have the worst air quality along with the pollutants that continue to cause threats to the environment.
You would go to this form of government if you where looking to take action on the air quality, not just find information.
http://www.environment.gov.au/atmosphere/airquality/index.html