Daily Air Quality Index summaries from EPA monitors in Mahoning, Ohio, 1980–2025.
63%
Good days in 2025
44
Median daily AQI, 2025
2
Days above 100 in 2025
363
Days with an AQI in 2025 (of 365)
In 2025, EPA reported a daily Air Quality Index (AQI) for Mahoning, Ohio on 363 days. 230 of those days (63%) were in the Good range, and the median daily AQI was 44. That median is about the same as the typical monitored county in Ohio (median 43 across 36 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 215 days. Across the years with fuller monitoring, the share of Good days rose: an average of 43% in 1980–1982 versus 60% in 2023–2025.
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
Fine particles (PM2.5)
215
59%
Ozone
148
41%
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
363
230
131
2
0
0
0
44
65
122
PM2.5
2024
361
239
122
0
0
0
0
44
61
93
PM2.5
2023
365
187
172
3
2
1
0
49
73
226
PM2.5
2022
349
214
132
3
0
0
0
46
62
129
PM2.5
2021
365
205
159
1
0
0
0
47
66
110
PM2.5
2020
365
251
113
1
0
0
0
43
58
142
PM2.5
2019
360
232
128
0
0
0
0
46
59
84
PM2.5
2018
365
242
123
0
0
0
0
43
59
90
PM2.5
2017
365
237
128
0
0
0
0
44
60
80
PM2.5
2016
366
222
144
0
0
0
0
45
58
78
PM2.5
2015
363
192
170
1
0
0
0
49
71
112
PM2.5
2014
363
154
208
1
0
0
0
52
66
114
PM2.5
2013
360
152
207
1
0
0
0
53
68
119
PM2.5
2012
366
144
212
8
2
0
0
53
76
169
PM2.5
2011
365
138
220
7
0
0
0
54
74
140
PM2.5
2010
365
126
232
7
0
0
0
55
75
140
PM2.5
2009
295
173
122
0
0
0
0
45
70
100
Ozone
2008
363
113
242
8
0
0
0
56
81
141
PM2.5
2007
263
137
103
22
1
0
0
49
93
168
Ozone
2006
265
140
116
9
0
0
0
49
80
136
Ozone
2005
264
116
127
19
2
0
0
55
97
174
Ozone
2004
365
89
261
14
1
0
0
59
90
151
PM2.5
2003
365
71
279
12
1
2
0
61
87
212
PM2.5
2002
365
82
243
26
14
0
0
60
105
195
PM2.5
2001
359
72
248
34
4
1
0
62
101
202
PM2.5
2000
350
78
253
18
1
0
0
61
89
185
PM2.5
1999
348
58
262
22
6
0
0
64
96
177
PM2.5
1998
240
158
43
27
11
1
0
42
129
204
Ozone
1997
239
186
31
19
3
0
0
36
97
182
Ozone
1996
239
171
48
15
5
0
0
37
97
177
Ozone
1995
285
203
54
18
9
1
0
35
100
208
Ozone
1994
365
303
46
16
0
0
0
28
77
143
Ozone
1993
365
298
52
14
1
0
0
29
77
159
Ozone
1992
365
317
34
9
5
0
0
30
61
187
Ozone
1991
364
270
48
32
12
2
0
33
112
204
Ozone
1990
338
276
44
15
3
0
0
32
74
172
PM10
1989
331
252
64
8
7
0
0
35
77
164
PM10
1988
254
178
31
20
21
4
0
35
147
210
Ozone
1987
309
251
36
16
6
0
0
32
90
197
Ozone
1986
365
314
35
14
2
0
0
31
62
187
Ozone
1985
365
299
45
14
7
0
0
33
80
185
Ozone
1984
336
228
79
28
1
0
0
42
100
158
NO2
1983
365
243
81
29
11
1
0
41
105
218
NO2
1982
365
231
91
34
8
1
0
42
103
222
Ozone
1981
365
151
164
42
6
2
0
57
109
215
NO2
1980
366
90
176
90
9
1
0
73
111
218
NO2
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 Ohio with a similar median AQI in 2025
