Air Quality Ontario: Table: Ontario's Air Monitoring Stations

ozone O₃ Concentrations by stations.
Station	Location	O₃
Barrie	83 Perry St.	47
Belleville	2 Sidney St., Water Treatment Plant	46
Brampton	109 Mclaughlin Rd. S.	43
Brantford	324 Grand River Ave.	36
Burlington	North Shore Blvd. E. Lakeshore Rd.	31
Chatham	435 Grand Ave. W.	55
Cornwall	Bedford St. 3rd St. W.	35
Dorset	1026 Bellwood Acres Rd.	30
Grand Bend	Point Blake Conservation Area	56
Guelph	Exhibition St. Clark St. W.	47
Hamilton Downtown	Elgin St. Kelly St.	49
Hamilton Mountain	250 Fennell Ave. W.	45
Hamilton West	Main St. W. Hwy 403	48
Kingston	23 Beechgrove Lane	51
Kitchener	West Ave. Homewood Ave.	48
London	42 St. Julien St.	64
Milton	1120 Main St. E.	43
Mississauga	3359 Mississauga Rd. N., U of T Campus	9
Newmarket	Eagle St. W. McCaffrey Rd.	49
North Bay	Elgin St. Kelly St.	44
Oakville	Eighth Line, Glenashton Dr., Halton Res.	38
Oshawa	Brittania Ave. W., Ep Taylor Stables	45
Ottawa Downtown	Rideau St. Wurtemburg St.	52
Parry Sound	7 Bay St.	48
Peterborough	10 Hospital Dr.	50
Port Stanley	43665 Dexter Line, Elgin Water T. Plt	67
Sarnia	700 Christina St. N.	53
Sault Ste. Marie	Sault College	45
St. Catharines	Argyle Cres., Pump Stn.	56
Sudbury	155 Elm St.	52
Thunder Bay	421 James St. S.	22
Tiverton	4th Concession, Bruce Rd. 23	66
Toronto Downtown	55 John St.	37
Toronto East	Kennedy Rd. Lawrence Ave. E.	36
Toronto North	4905 Dufferin St., Eccc	42
Toronto West	125 Resources Rd.	33
Windsor Downtown	467 University Ave. W.	54
Windsor West	College Ave. South St.	56

Ontario's ambient air monitoring stations

ozone O₃ Concentrations for Saturday, July 5, 2025, 11:00 pm

Note: The pollutant concentrations on this web page are based on automatically polled data and have not undergone final verification.

Note: N/A (not available) denotes invalid or missing data.
Ontario 1-hour AAQC for O₃ = 80 ppb