Illinois PM2.5 24-hour Exceedance Summary
Value in each column is 24-hour concentration - standard of 35 micrograms per cubic meter
(values in micrograms per cubic meter)
| Region | County | Site | 2024 None to date |
| Chicago Metropolitan | Cook | Alsip | |
| Cook | Chicago-Com Ed | ||
| Cook | Chicago-Springfield Pump | ||
| Cook | Chicago-Mayfair | ||
| Cook | Chicago-Washington HS | ||
| Cook | Cicero | ||
| Cook | Des Plaines | ||
| Cook | Kingery Near-Road | ||
| Cook | McCook | ||
| Cook | Northbrook | ||
| Cook | Schiller Park | ||
| Cook | Summit | ||
| Du Page | Naperville | ||
| Kane | Aurora | ||
| Kane | Elgin | ||
| McHenry | Cary | ||
| Will | Braidwood | ||
| Will | Joliet | ||
| Metro-East | Jersey | Jerseyville | |
| Madison | Alton | ||
| Madison | Granite City-23rd&Madison | ||
| Madison | Granite City-Gateway Medical | ||
| Madison | Wood River | ||
| Randolph | Houston | ||
| St Clair | E St. Louis | ||
| Northern Illinois | Rock Island | Rock Island | |
| Winnebago | Rockford | ||
| West Central Illinois | Peoria | Peoria | |
| Sangamon | Springfield | ||
| East Central Illinois | Champaign | Bondville | |
| Champaign | Champaign | ||
| Macon | Decatur | ||
| McLean | Normal | ||
| Southeast Illinois | Hamilton | Knight Prairie |