8-hour Exceedances Summary
Values in each column is 8-hour concentration - standard of 70 parts per billion;
| Region |
County |
Site |
10/3/25 |
10/1/25 |
9/19/25 |
9/18/25 |
9/17/25 |
9/12/25 |
9/10/25 |
8/16/25 |
8/6/25 |
8/5/25 |
7/29/25 |
7/22/25 |
7/15/25 |
7/14/25 |
7/3/25 |
7/2/25 |
6/16/25 |
6/12/25 |
6/11/25 |
6/7/25 |
6/5/25 |
| Chicago Metropolitan |
Cook |
Alsip |
|
|
|
74 |
|
|
|
|
|
|
|
|
|
|
|
|
71 |
71 |
|
|
|
| Cook |
Chicago - Com Ed |
|
|
|
76 |
|
|
|
|
73 |
|
|
|
|
|
|
|
71 |
|
|
|
|
| Cook |
Chicago - SWFP |
73 |
|
79 |
73 |
|
80 |
|
79 |
75 |
73 |
78 |
|
75 |
89 |
|
75 |
78 |
|
77 |
|
|
| Cook |
Chicago - Taft |
|
|
|
71 |
|
|
|
|
76 |
|
89 |
|
|
84 |
71 |
|
74 |
|
74 |
|
|
| Cook |
Cicero |
|
|
|
|
|
|
|
|
73 |
|
|
|
|
78 |
|
|
73 |
|
73 |
|
|
| Cook |
Des Plaines |
|
|
|
|
|
|
|
|
71 |
|
78 |
|
|
75 |
|
|
|
|
|
|
|
| Cook |
Evanston |
71 |
|
72 |
|
|
71 |
|
|
|
|
76 |
|
74 |
80 |
|
73 |
73 |
|
72 |
|
|
| Cook |
Lemont |
|
|
|
80 |
72 |
|
|
|
|
73 |
|
|
|
|
|
|
|
|
|
|
|
| Cook |
Northbrook |
|
|
|
|
|
|
|
|
|
|
82 |
|
|
77 |
|
|
|
|
|
|
|
| Cook |
Schiller Park |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| DuPage |
Lisle |
|
|
|
|
|
|
|
|
|
72 |
|
|
|
|
|
|
|
|
|
|
|
| Kane |
Elgin |
|
|
|
83 |
72 |
|
|
|
|
|
|
|
|
|
|
|
81 |
75 |
|
72 |
|
| Lake |
Zion |
|
|
|
|
|
|
|
|
|
|
|
|
71 |
|
|
|
73 |
|
71 |
|
|
| McHenry |
Cary |
|
|
72 |
84 |
|
73 |
|
|
76 |
|
|
76 |
|
|
|
|
80 |
72 |
72 |
|
|
| Will |
Braidwood |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Metro-East |
Jersey |
Jerseyville |
|
71 |
|
88 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
76 |
|
|
| Madison |
Alton |
|
|
|
78 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Madison |
Maryville |
|
|
|
|
|
|
71 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Madison |
Wood River |
|
|
|
75 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Randolph |
Houston |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| St. Clair |
East St. Louis |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Northern Illinois |
Rock Island |
Rock Island |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Winnebago |
Loves Park |
|
|
|
74 |
|
|
|
|
|
|
|
|
|
|
|
|
|
73 |
|
|
|
| West Central Illinois |
Adams |
Quincy |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Macoupin |
Nilwood |
|
|
|
|
72 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Peoria |
Peoria |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
73 |
| Peoria |
Peoria Heights |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
73 |
| Sangamon |
Springfield |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| East Central Illinois |
Champaign |
Thomasboro |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| McLean |
Normal |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
74 |
| Macon |
Decatur |
|
|
|
72 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Southeast Illinois |
Effingham |
Effingham |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Hamilton |
Knight Prairie Township |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|