Air Quality Health Index (AQHI)

The Air Quality Health Index replaced the Air Quality Index on June 24, 2015. For more information about the new AQHI index, see What is the Air Quality Health Index?

Air Quality Health Index Categories, Values and Associated Colours

Air Quality Health Index Categories and Values
1	2	3	4	5	6	7	8	9	10	+
Low Risk (1 - 3)			Moderate Risk (4 - 6)			High Risk (7 - 10)				Very High Risk

AQHI Observations and Forecasts

• Current AQHI calculated at 9:00 pm EDT August 4, 2020
• Environment Canada location AQHI forecasts updated at 5:00 pm EDT August 4, 2020

Current and Forecast Air Quality Health Index for Ontario

Location	Current	Forecast Maximums
	Tuesday, 9:00 pm	Tuesday Night	Wednesday
Barrie	1 Low Risk	2 Low Risk	2 Low Risk
Belleville	2 Low Risk	2 Low Risk	2 Low Risk
Brampton	1 Low Risk	3 Low Risk	2 Low Risk
Brantford	1 Low Risk	3 Low Risk	2 Low Risk
Chatham	1 Low Risk	2 Low Risk	3 Low Risk
Cornwall	1 Low Risk	2 Low Risk	2 Low Risk
Dorset	1 Low Risk	2 Low Risk	2 Low Risk
Grand Bend	1 Low Risk	2 Low Risk	3 Low Risk
Guelph	1 Low Risk	3 Low Risk	2 Low Risk
Milton	2 Low Risk	3 Low Risk	2 Low Risk
Burlington	3 Low Risk	3 Low Risk	2 Low Risk
Hamilton Downtown	2 Low Risk	3 Low Risk	2 Low Risk
Hamilton Mountain	2 Low Risk	3 Low Risk	2 Low Risk
Hamilton West	2 Low Risk	3 Low Risk	2 Low Risk
Kingston	2 Low Risk	2 Low Risk	2 Low Risk
Kitchener	1 Low Risk	3 Low Risk	2 Low Risk
London	1 Low Risk	2 Low Risk	3 Low Risk
Mississauga	2 Low Risk	3 Low Risk	2 Low Risk
Newmarket	1 Low Risk	3 Low Risk	2 Low Risk
North Bay	1 Low Risk	2 Low Risk	2 Low Risk
Oakville	2 Low Risk	3 Low Risk	2 Low Risk
Oshawa	N/A	3 Low Risk	2 Low Risk
Ottawa Downtown	1 Low Risk	2 Low Risk	2 Low Risk
Parry Sound	1 Low Risk	2 Low Risk	2 Low Risk
Petawawa	1 Low Risk	2 Low Risk	2 Low Risk
Peterborough	2 Low Risk	3 Low Risk	2 Low Risk
Port Stanley	1 Low Risk	2 Low Risk	3 Low Risk
Sarnia	1 Low Risk	2 Low Risk	3 Low Risk
Sault Ste. Marie	1 Low Risk	2 Low Risk	2 Low Risk
St. Catharines	3 Low Risk	3 Low Risk	2 Low Risk
Sudbury	1 Low Risk	2 Low Risk	2 Low Risk
Thunder Bay	1 Low Risk	2 Low Risk	2 Low Risk
Tiverton	1 Low Risk	2 Low Risk	2 Low Risk
Toronto Downtown	1 Low Risk	3 Low Risk	2 Low Risk
Toronto East	2 Low Risk	3 Low Risk	2 Low Risk
Toronto North	2 Low Risk	3 Low Risk	2 Low Risk
Toronto West	2 Low Risk	3 Low Risk	2 Low Risk
Windsor Downtown	1 Low Risk	3 Low Risk	3 Low Risk
Windsor West	N/A	3 Low Risk	3 Low Risk

Air Quality Health Index Categories and Health Messages

The table below provides the health messages for each category of the Air Quality Health Index for the "at risk" population and the general population.

Health Risk	Air Quality Health Index	Health Messages
		At Risk Population*	General Population
Low	1 - 3	Enjoy your usual outdoor activities.	Ideal air quality for outdoor activities.
Moderate	4 - 6	Consider reducing or rescheduling strenuous activities outdoors if you are experiencing symptoms.	No need to modify your usual outdoor activities unless you experience symptoms such as coughing and throat irritation.
High	7 - 10	Reduce or reschedule strenuous activities outdoors. Children and the elderly should also take it easy.	Consider reducing or rescheduling strenuous activities outdoors if you experience symptoms such as coughing and throat irritation.
Very High	Above 10	Avoid strenuous activities outdoors. Children and the elderly should also avoid outdoor physical exertion.	Reduce or reschedule strenuous activities outdoors, especially if you experience symptoms such as coughing and throat irritation.

* People with heart or breathing problems are at greater risk. Follow your doctor's usual advice about exercising and managing your condition.