Toronto Green

Ozone and UV Index 

Ozone (O3) is a colourless, odourless gas at ambient concentrations and is a major component of smog. Ground-level ozone is not emitted directly into the atmosphere.  It results from photochemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOCs) in the presence of sunlight.  High levels typically occur from May to September, between noon and early evening. 

TOTAL OZONE MAP - click on the image below for the latest reading



Click here for live UV readings.  For more detailed ozone readings from Environment Canada, click

Air Quality Index  

The Air Quality Index (AQI) is an indicator of air quality, based on hourly pollutant measurements of some or all of the six most common air pollutants: sulphur dioxide, ozone, nitrogen dioxide, total reduced sulphur compounds, carbon monoxide and fine particulate matter.  For more information, visit the Ontario Ministry of the Environment website.

Click on the image below for the latest Air Quality Index readings and forecast.

Air Quality Health Index 

The information below is taken directly from Environment Canada.  To learn more about the new Air Quality Health Index, visit the Government of Canada site.



Click on the city below for the current AQHI

 Brampton | Burlington | Mississauga | Newmarket | Oakville | Oshawa | Toronto

The Air Quality Health Index or "AQHI" is a scale designed to help you understand what the air quality around you means to your health. 

It is a health protection tool that is designed to help you make decisions to protect your health by limiting short-term exposure to air pollution and adjusting your activity levels during increased levels of air pollution. It also provides advice on how you can improve the quality of the air you breathe.

       How can I help to reduce air pollution and create a "Green Toronto"?

 Participate in various government programs and local environmental initiatives:

City of Toronto 20/20 The Way to Clean Air:

Clean Air Online - Government of Ontario:

Taking Action Air Quality Ontario:

Clean Air Canada:

Health Canada Effects of Air Pollution:

Government of Canada Air Action:

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