Gary-IITRI

Data time: 11/8/2026 2:00 PM CST

Location

Address:: 201 Mississippi St. (IITRI Bunker)
City:: Gary
Latitude:: 41.606563
Longitude:: -87.305015
Region:: North West

Air Quality Information
Pollutant	Concentration	Units of Measure
O3 1-Hour Average	25	PPB
O3 8-Hour Average	17	PPB

Monitored Pollutants
Pollutant	Concentration	Units of Measure
O3	25.9	PPB

Site Details

The Gary IITRI monitoring site began operating in March 1993 (PM10 and Meteorological parameters). Ozone and VOCs were added in July 1995, SO2 in June 1997, NO2 in June 1998, PM2.5 in March 1999 and PM2.5 speciation in April 2005. The monitoring objective is to monitor the ambient air in Gary near the US Steel Steelmill.

Historical Data Concentration

Hour	AQI	Class	Program	Responsible Pollutant	Activity Caution	Risk Groups
14:00	20	Good	O3 1-Hour Average	O3	None	None
14:00	16	Good	O3 8-Hour Average	O3	None	Children and people with asthma are the groups most at risk.
13:00	18	Good	O3 1-Hour Average	O3	None	None
13:00	15	Good	O3 8-Hour Average	O3	None	Children and people with asthma are the groups most at risk.
12:00	15	Good	O3 1-Hour Average	O3	None	None
12:00	13	Good	O3 8-Hour Average	O3	None	Children and people with asthma are the groups most at risk.
11:00	14	Good	O3 1-Hour Average	O3	None	None
11:00	12	Good	O3 8-Hour Average	O3	None	Children and people with asthma are the groups most at risk.
10:00	12	Good	O3 1-Hour Average	O3	None	None
10:00	12	Good	O3 8-Hour Average	O3	None	Children and people with asthma are the groups most at risk.
09:00	12	Good	O3 1-Hour Average	O3	None	None