Monitoring Air Quality

To support the Air Quality Health Index (AQHI), the Ministry monitors up to 6 common pollutants at each of the 39 stations across the provincial AQHI network, including:

Ontario Air Quality Health Index Monitoring Network

Pollutants are monitored at each station.
CITY/TOWNO3PM2.5NO2SO2COTRS
Barrie X X X - - -
Belleville X X X - - -
Brampton X X X - - -
Brantford X X X - - -
Burlington X X X - - -
Chatham X X X - - -
Cornwall X X X - - -
Dorset X X - - - -
Grand Bend X X X - - -
Guelph X X X - - -
Hamilton Downtown X X X X X X
Hamilton Mountain X X X X - -
Hamilton West X X X - - -
Kingston X X X - - -
Kitchener X X X - - -
London X X X - - -
Milton X X X X - -
Mississauga X X X - - -
Newmarket X X X - - -
North Bay X X X - - -
Oakville X X X - - -
Oshawa X X X - - -
Ottawa Downtown X X X - - -
Parry Sound X X X - - -
Peterborough X X X - - -
Port Stanley X X X - - -
Sarnia X X X X - X
Sault Ste. Marie X X X X - -
St. Catharines X X X - - -
Sudbury X X X X - -
Thunder Bay X X X - - -
Tiverton X X - - - -
Toronto Downtown X X X - - -
Toronto East X X X - - -
Toronto North X X X X X -
Toronto West X X X X X -
Windsor Downtown X X X X X -
Windsor West X X X X - X

For current AQHI information, please visit airqualityontario, Environment Canada, or call the AQHI Reporting System line at: (416) 246-0411 in the Toronto area or 1 (800) 387-7768 toll free.