A NSW Government website

Understanding air quality data

Learn about air quality information, find out what air quality categories are and how we determine them.

We report on air quality in near real-time using up-to-date, accurate concentration data on hourly and daily basis. For most parts of the network, air quality is also presented as air quality categories derived from concentration data. On a daily basis every afternoon, we issue a next-day air quality forecast for Sydney. We share this information in various ways:

  • in tables, maps and text
  • by pollutant, location (site, region) and time
  • on our website, via email/SMS subscription, and in reports.
Sunrise at South Head, Sydney Harbour National Park

Air quality categories help us understand air quality and modify our activities if pollution levels are high.

OEH scientist checking a dust watch monitoring station in Gunnedah

Quality assurance procedures are applied to ensure the validity and integrity of air quality data we acquire and report.

Air pollution monitoring satellite modelling on computer

Air pollutants are measured in various units. Find out about the units and how to convert them so you can compare our data with data from other sources.

A view of the mountains from Warrumbungle National Park in the Central West region of New South Wales

Setting air quality standards and goals are essential for protecting human health and the environment from the adverse effects of air pollution.

A view of the landscape from Oxley Wild Rivers National Park in the Northern Tablelands region of New South Wales

Air quality data readings are taken continuously and averaged to give hourly and daily air quality information.

A scientist analysing for pollutants

Glossary of words, phrases and acronyms used in air quality monitoring and reporting.