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Region 1: EPA New England

Serving Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont & 10 Tribal Nations

Historical Exceedance Days in New England

The chart below shows the number of days air quality monitors in each New England state recorded ozone concentrations exceeding the 1997 8-hour ozone standard (that is, days greater than 0.084 parts per million (ppm)), as well as the number of days exceeding the 2008 8-hour ozone standard (that is, days greater than 0.075 ppm).

Exceedance Days Per Area(Click on an area for a graph of the data)
Year New England
# days >		 CT
# days >		 ME
# days >		 MA
# days >		 NH
# days >		 RI
# days >		 VT
# days >
0.084 0.075 0.084 0.075 0.084 0.075 0.084 0.075 0.084 0.075 0.084 0.075 0.084 0.075
1983 90 113 84 103 21 36 62 84 10 18 24 34 4 7
1984 60 79 54 63 25 34 44 65 10 20 28 42 4 10
1985 50 70 41 58 21 35 38 53 8 16 16 27 6 9
1986 35 53 28 41 9 17 24 32 9 16 12 22 1 6
1987 46 58 37 44 10 20 23 35 13 28 18 27 3 11
1988 56 72 50 62 35 40 43 63 27 37 19 29 14 26
1989 31 62 26 41 16 21 21 43 11 16 9 14 2 5
1990 31 57 24 44 15 21 22 37 9 20 13 18 5 8
1991 40 54 34 46 17 26 26 45 13 22 20 28 10 16
1992 27 47 19 29 12 22 20 36 8 18 5 12 6 11
1993 30 51 27 39 14 20 23 40 8 17 7 11 4 9
1994 33 53 28 39 10 22 20 39 9 19 8 21 2 13
1995 29 48 24 35 14 20 20 39 9 19 11 18 3 13
1996 20 44 16 33 5 20 15 28 6 14 4 12 3 4
1997 30 47 27 34 11 16 24 38 10 16 11 19 2 11
1998 28 52 25 44 11 16 12 36 7 14 5 11 0 5
1999 35 50 33 43 10 21 22 36 10 19 13 16 3 11
2000 19 27 13 23 3 5 5 16 1 5 8 14 1 2
2001 32 47 26 39 15 22 27 37 11 22 15 26 2 9
2002 43 53 36 49 17 28 30 43 13 23 17 33 5 13
2003 17 34 14 26 5 15 11 27 1 10 10 13 0 4
2004 13 28 6 20 1 11 8 16 5 10 4 5 2 4
2005 26 43 20 30 5 15 17 31 4 17 8 17 0 4
2006 16 37 13 29 2 10 12 26 2 10 3 13 0 0
2007 26 53 17 42 8 14 20 38 8 22 8 18 1 5
2008 13 30 8 22 0 4 9 18 2 10 4 6 0 3
2009 4 11 1 6 2 3 1 8 0 2 0 1 0 0
2010 9 29 5 24 2 8 4 14 0 8 1 6 0 0
2011* 11 16 10 14 2 3 5 10 1 2 0 6 0 1

*Please note that the 2011 data is preliminary and subject to change.

Serving Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont, & 10 Tribal Nations

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