Daily Air Quality Index summaries from EPA monitors in Bennington, Vermont, 1986–2025.
84%
Good days in 2025
37
Median daily AQI, 2025
2
Days above 100 in 2025
360
Days with an AQI in 2025 (of 365)
In 2025, EPA reported a daily Air Quality Index (AQI) for Bennington, Vermont on 360 days. 301 of those days (84%) were in the Good range, and the median daily AQI was 37. That median is about the same as the typical monitored county in Vermont (median 37 across 3 counties), and lower than the typical monitored U.S. county (40). The main pollutant was ozone on 284 days. Across the years with fuller monitoring, the share of Good days rose: an average of 72% in 1987–1989 versus 85% in 2023–2025.
Years with fewer than 120 monitored days (1986) are shown in the table but left out of comparisons and trend statements.
How the days broke down each year
Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Typical and high-end AQI over time
The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.
Median daily AQI
90th-percentile daily AQI
Main pollutant by day, 2025
On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.
Pollutant
Days as main pollutant
Share of monitored days
Ozone
284
79%
Fine particles (PM2.5)
76
21%
Year-by-year data
Annual AQI summary by year
Year
Days with AQI
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Median AQI
90th pct.
Max AQI
Main pollutant
2025
360
301
57
2
0
0
0
37
54
122
Ozone
2024
365
332
33
0
0
0
0
36
50
80
Ozone
2023
359
290
63
4
2
0
0
38
56
157
Ozone
2022
365
324
41
0
0
0
0
37
51
74
Ozone
2021
365
307
57
1
0
0
0
37
55
115
Ozone
2020
366
330
36
0
0
0
0
37
50
73
Ozone
2019
365
329
36
0
0
0
0
37
50
95
Ozone
2018
365
300
64
1
0
0
0
37
55
101
Ozone
2017
364
317
46
1
0
0
0
37
53
101
Ozone
2016
366
325
40
1
0
0
0
37
51
112
Ozone
2015
365
276
89
0
0
0
0
39
57
97
Ozone
2014
362
288
74
0
0
0
0
38
56
90
Ozone
2013
365
294
70
1
0
0
0
39
56
101
Ozone
2012
366
286
79
1
0
0
0
39
56
108
Ozone
2011
361
239
121
1
0
0
0
42
61
140
PM2.5
2010
364
283
79
2
0
0
0
38
62
101
Ozone
2009
359
274
82
3
0
0
0
38
60
115
Ozone
2008
350
266
81
3
0
0
0
39
62
147
Ozone
2007
363
301
55
7
0
0
0
36
61
136
Ozone
2006
356
304
49
3
0
0
0
34
57
119
Ozone
2005
340
265
66
9
0
0
0
41
62
136
Ozone
2004
360
304
50
5
1
0
0
34
58
164
Ozone
2003
354
294
54
6
0
0
0
36
61
140
Ozone
2002
301
208
75
13
5
0
0
40
77
164
Ozone
2001
263
169
79
13
2
0
0
45
84
169
Ozone
2000
279
210
65
3
1
0
0
37
64
164
Ozone
1999
277
169
90
15
3
0
0
44
80
172
Ozone
1998
253
182
64
7
0
0
0
42
77
143
Ozone
1997
241
184
47
8
2
0
0
41
77
179
Ozone
1996
255
193
52
7
3
0
0
38
69
169
Ozone
1995
262
208
44
10
0
0
0
37
67
150
Ozone
1994
246
177
59
9
1
0
0
43
80
164
Ozone
1993
252
191
51
7
3
0
0
41
78
185
Ozone
1992
249
198
39
11
1
0
0
39
68
156
Ozone
1991
219
158
42
11
8
0
0
42
93
190
Ozone
1990
207
150
42
11
4
0
0
42
87
159
Ozone
1989
206
140
57
8
1
0
0
43
87
174
Ozone
1988
194
130
31
22
9
2
0
44
122
214
Ozone
1987
196
156
29
9
2
0
0
40
84
161
Ozone
1986
94
82
7
5
0
0
0
32
64
147
Ozone
What this data can and can’t tell you
It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.
It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.
Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.
Counties in Vermont with a similar median AQI in 2025
