The report below displays data on the total number of days in Michigan with an Air Quality Index Value of
over 100. This data has been compiled from 1990-2007. Some states have multiple monitoring stations and each will be listed in the reports below.
Other states do not have any monitoring stations in which case we have selected the closest station available.
Year
Detroit
Grand Rapids-Muskegon-Holland
1990
17
20
1991
38
38
1992
14
13
1993
15
12
1994
21
30
1995
20
32
1996
26
19
1997
18
19
1998
33
32
1999
41
36
2000
17
15
2001
41
31
2002
34
31
2003
25
22
2004
11
9
2005
38
31
2006
12
16
2007
21
22
According to the EPA, an Air Quality Index Value of over 100 presents some level of health concern. The higher the number, the
higher the level of concern. The EPA provides the following table and more information on Air Quality Index can be found at
WikiPedia.
