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Illinois Ozone Highs

1-Hr/8-Hr High Concentrations
(Values in Parts Per Billion)
First number in each column is 1-hour concentration - Standard of 125 parts per billion
Second number in each column is 8-hour concentration. - Standard of 75 parts per billion;
Region  County Site 10/25  10/26  10/27  10/28  10/29  10/30  10/31 
Chicago Metropolitan  Cook Alsip 45/41  41/33  48/41  32/23  18/14  18/13  33/33 
Cook Chicago - ComEd --/--  --/--  49/43  35/25  19/14  22/17  36/36 
Cook Chicago - SWFP 40/35  38/36  42/36  30/21  18/14  20/14  38/38 
Cook Chicago - Taft 47/43  38/33  51/44  31/24  26/17  18/18  39/37 
Cook Cicero 44/39  31/28  44/37  28/24  21/16  17/14  35/35 
Cook Des Plaines 43/40  40/33  47/41  29/23  24/15  18/17  32/29 
Cook Evanston 43/40  41/39  47/40  30/24  21/17  15/18  39/39 
Cook Lemont 45/41  39/35  52/46  32/24  22/16  20/17  35/33 
Cook Northbrook 46/42  38/35  52/45  30/26  24/18  20/19  37/35 
Cook Schiller Park 36/30  38/30  44/39  33/27  28/18  22/24  39/37 
DuPage Lisle 45/42  39/34  50/42  28/24  22/17  20/17  35/33 
Kane Elgin 42/39  41/36  50/44  26/23  24/17  19/17  34/32 
Lake Zion 47/43  40/39  56/50  34/28  23/18  25/21  39/37 
McHenry Cary 43/40  41/37  49/43  27/23  21/17  20/17  34/32 
Will Braidwood 46/42  42/37  51/45  32/28  18/17  22/20  34/33 
Metro East  Jersey Jerseyville 46/41  49/44  46/43  33/31  32/28  17/10  29/26 
Madison Alton 49/44  54/49  50/45  40/33  32/30  26/20  34/31 
Madison Maryville 52/45  54/48  53/49  43/35  33/31  30/25  33/30 
Madison Wood River 46/39  52/46  48/41  38/32  29/27  23/19  31/28 
Randolph Houston 57/51  65/59  58/56  49/42  40/34  43/38  40/36 
St. Clair East St. Louis 52/42  51/45  49/45  36/31  30/25  26/19  29/26 
Northern Illinois  Rock Island Rock Island 43/40  40/37  51/48  33/24  24/20  21/24  33/31 
Winnebago Loves Park 44/40  41/41  50/46  28/25  25/19  22/21  32/31 
West Central Illinois  Adams Quincy 45/39  50/45  46/44  38/35  31/28  31/24  30/27 
Macoupin Nilwood 47/41  29/27  --/--  35/32  31/28  27/20  31/28 
Peoria Peoria 46/34  41/36  45/45  34/31  21/18  10/12  31/29 
Peoria Peoria Heights 48/42  43/39  48/42  34/31  23/20  13/16  34/33 
Sangamon Springfield 46/38  46/42  46/43  35/33  26/24  22/18  32/29 
East Central Illinois  Champaign Thomasboro --/--  --/--  --/--  35/29  20/17  24/20  29/28 
McLean Normal 48/38  44/40  50/45  35/32  21/19  23/19  33/31 
Macon Decatur 54/47  53/49  48/45  44/37  29/26  29/24  32/30 
Southeast Illinois  Effingham Effingham 49/43  47/43  53/48  43/34  32/29  29/24  30/29 
Hamilton Knight Prairie Township 56/51  60/53  59/56  48/40  36/33  39/32  37/35