The report below displays data on the total number of days in Arizona 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
Phoenix-Mesa
Tucson
1990
20
7
1991
24
4
1992
33
6
1993
37
14
1994
33
10
1995
41
14
1996
45
8
1997
33
8
1998
47
7
1999
47
8
2000
35
5
2001
25
0
2002
22
7
2003
26
7
2004
9
0
2005
23
8
2006
25
9
2007
11
1
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.