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Get your AQHI for Toronto!
Did you know ...
If you have heart problems or difficulty breathing, you should monitor your symptoms closely as the index reading rises.
About the Air Quality Health Index
The quality of the air we breathe has long been recognized as an important element of public health. The new Air Quality Health Index (AQHI) is the first health-based index that combines the quality of air with known health effects. The AQHI takes into account how the level of exposure to multiple pollutants, even at low levels of exposure, can affect your health.
The AQHI is a personal health tool. It provides specific information to individuals who are ‘at-risk’ from air pollution and to the general Canadian public. This new index helps you make informed choices about your activities throughout the day to protect your health.
This national initiative was developed in partnership with federal, provincial and municipal governments and agencies. The National pilot of the Air Quality Health Index was launched in Toronto on July 9, 2007 and over the coming months, more locations across Canada will be receiving the Health Index localized for their community. Visit this site often for updates on the new locations.
Please select from the options below to learn more about the AQHI.
- What is the Air Quality Health Index (AQHI)?
- Don't we already have an Air Quality Index (AQI)?
- How is the AQHI calculated?
- What is the scale for the new AQHI?
- How can I find out more about the air quality in my community?
What is the Air Quality Health Index (AQHI)?
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.
This index pays particular attention to people who are sensitive to air pollution and provides them with advice on how to protect their health during air quality levels associated with low, moderate, high and very high health risks.
The AQHI communicates four primary things;
- A number from 1 and 10+ indicating the quality of the air. The higher the number, the greater the health risk associated with the air quality. When the amount of air pollution is very high, the number will be reported as 10+.
- A category that describes the level of health risk associated with the index reading (e.g. Low, Moderate, High, or Very High Health Risk).
- Health messages customized to each category for both the general population and the ‘at risk’ population.
- Current hourly AQHI readings and maximum forecasted values for today, tonight and tomorrow.
The AQHI is designed to give you this information in one place along with some suggestions on how you might adjust your activity levels depending on your individual health risk from air pollution. Follow this guide on how to use the AQHI or learn about the history of the AQHI.
Don't we already have an Air Quality Index (AQHI)?
While the Air Quality Index (AQI) has been reported for many years, this new Air Quality Health Index (AQHI) has been created with a different goal - to report on the health risks that are posed by different levels of a mixture of air pollutants.
Read more about how the AQHI and the AQI differ.
How is the AQHI calculated?
The AQHI is calculated based on the relative risks of a combination of common air pollutants which are known to harm human health. These pollutants include:
- Ozone (O3) at ground level,
- Particulate Matter (PM2.5/PM10) and
- Nitrogen Dioxide (NO2).
What is the scale for the new AQHI?
The AQHI is measured on a scale ranging from 1-10+. The AQHI index values are also grouped into health risk categories as shown below. These categories help you to easily and quickly identify your level of risk.
- 1-3 Low health risk
- 4-6 Moderate health risk
- 7-10 High health risk
- 10 + Very high health risk
More information on the scale and the AQHI categories.
How can I find out about the air quality in my community?
If you live in the city of Toronto pilot area, visit Toronto AQHI for your local AQHI or Toronto Public Health's Web site at www.toronto.ca/health/aqhi.
Additional pilot locations will be established across Canada in the months to come. Visit our pilot locations Web page to find out about locations near you.
If you reside outside the AQHI Toronto pilot, please contact your local public health office, Ministry of Environment air monitoring branch, or local lung association chapter for available local resources on air quality.
Please see Learn More for more information.
