Information about air quality

Questions about air quality

• Frequently asked questions
• Health messages and air quality advice
• Wildfire smoke and air quality health

Ontario's air quality monitoring system

• Monitoring air quality
• Monitored pollutants
  • Ozone
  • Fine particulate matter
  • Nitrogen dioxide
  • Sulphur dioxide
  • Carbon monoxide
  • Total reduced sulphur compounds

Data sets

• Air quality alert statistics: Ontario smog events from 2015 to 2024
• Atom news feeds (XML): Current air quality observations, forecasts and alerts
• Historical air quality pollutant data
• Data disclaimer

Support and other resources

• Air quality publications
• Contact information
• Français