EnviroNearby

Summit County, Ohio air quality history

Daily Air Quality Index summaries from EPA monitors in Summit, Ohio, 1980–2025.

64%
Good days in 2025
44
Median daily AQI, 2025
3
Days above 100 in 2025
365
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Summit, Ohio on 365 days. 232 of those days (64%) 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 211 days. Across the years with fuller monitoring, the share of Good days fell: an average of 69% in 1980–1982 versus 63% 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.

Share of monitored days in each AQI category, by year0%25%50%75%100%1980: Good 182 of 364 days1980: Moderate 133 of 364 days1980: Unhealthy for Sensitive Groups 31 of 364 days1980: Unhealthy 16 of 364 days1980: Very Unhealthy 2 of 364 days19801981: Good 293 of 358 days1981: Moderate 38 of 358 days1981: Unhealthy for Sensitive Groups 15 of 358 days1981: Unhealthy 10 of 358 days1981: Very Unhealthy 2 of 358 days1982: Good 278 of 364 days1982: Moderate 53 of 364 days1982: Unhealthy for Sensitive Groups 22 of 364 days1982: Unhealthy 10 of 364 days1982: Very Unhealthy 1 of 364 days1983: Good 264 of 365 days1983: Moderate 51 of 365 days1983: Unhealthy for Sensitive Groups 33 of 365 days1983: Unhealthy 12 of 365 days1983: Very Unhealthy 5 of 365 days1984: Good 280 of 366 days1984: Moderate 55 of 366 days1984: Unhealthy for Sensitive Groups 23 of 366 days1984: Unhealthy 8 of 366 days1985: Good 272 of 365 days1985: Moderate 60 of 365 days1985: Unhealthy for Sensitive Groups 27 of 365 days1985: Unhealthy 6 of 365 days19851986: Good 270 of 365 days1986: Moderate 60 of 365 days1986: Unhealthy for Sensitive Groups 28 of 365 days1986: Unhealthy 7 of 365 days1987: Good 276 of 365 days1987: Moderate 52 of 365 days1987: Unhealthy for Sensitive Groups 25 of 365 days1987: Unhealthy 11 of 365 days1987: Very Unhealthy 1 of 365 days1988: Good 272 of 366 days1988: Moderate 31 of 366 days1988: Unhealthy for Sensitive Groups 29 of 366 days1988: Unhealthy 24 of 366 days1988: Very Unhealthy 10 of 366 days1989: Good 264 of 365 days1989: Moderate 64 of 365 days1989: Unhealthy for Sensitive Groups 23 of 365 days1989: Unhealthy 11 of 365 days1989: Very Unhealthy 3 of 365 days1990: Good 285 of 365 days1990: Moderate 49 of 365 days1990: Unhealthy for Sensitive Groups 25 of 365 days1990: Unhealthy 5 of 365 days1990: Very Unhealthy 1 of 365 days19901991: Good 251 of 365 days1991: Moderate 58 of 365 days1991: Unhealthy for Sensitive Groups 30 of 365 days1991: Unhealthy 24 of 365 days1991: Very Unhealthy 2 of 365 days1992: Good 319 of 366 days1992: Moderate 31 of 366 days1992: Unhealthy for Sensitive Groups 12 of 366 days1992: Unhealthy 4 of 366 days1993: Good 279 of 365 days1993: Moderate 57 of 365 days1993: Unhealthy for Sensitive Groups 20 of 365 days1993: Unhealthy 9 of 365 days1994: Good 287 of 365 days1994: Moderate 49 of 365 days1994: Unhealthy for Sensitive Groups 27 of 365 days1994: Unhealthy 2 of 365 days1995: Good 287 of 365 days1995: Moderate 55 of 365 days1995: Unhealthy for Sensitive Groups 13 of 365 days1995: Unhealthy 10 of 365 days19951996: Good 288 of 366 days1996: Moderate 43 of 366 days1996: Unhealthy for Sensitive Groups 26 of 366 days1996: Unhealthy 9 of 366 days1997: Good 298 of 365 days1997: Moderate 49 of 365 days1997: Unhealthy for Sensitive Groups 14 of 365 days1997: Unhealthy 4 of 365 days1998: Good 261 of 365 days1998: Moderate 58 of 365 days1998: Unhealthy for Sensitive Groups 33 of 365 days1998: Unhealthy 12 of 365 days1998: Very Unhealthy 1 of 365 days1999: Good 55 of 365 days1999: Moderate 262 of 365 days1999: Unhealthy for Sensitive Groups 37 of 365 days1999: Unhealthy 11 of 365 days2000: Good 67 of 366 days2000: Moderate 273 of 366 days2000: Unhealthy for Sensitive Groups 23 of 366 days2000: Unhealthy 3 of 366 days20002001: Good 64 of 365 days2001: Moderate 255 of 365 days2001: Unhealthy for Sensitive Groups 33 of 365 days2001: Unhealthy 12 of 365 days2001: Very Unhealthy 1 of 365 days2002: Good 66 of 365 days2002: Moderate 255 of 365 days2002: Unhealthy for Sensitive Groups 22 of 365 days2002: Unhealthy 20 of 365 days2002: Very Unhealthy 2 of 365 days2003: Good 65 of 365 days2003: Moderate 278 of 365 days2003: Unhealthy for Sensitive Groups 18 of 365 days2003: Unhealthy 3 of 365 days2003: Very Unhealthy 1 of 365 days2004: Good 91 of 366 days2004: Moderate 257 of 366 days2004: Unhealthy for Sensitive Groups 16 of 366 days2004: Unhealthy 2 of 366 days2005: Good 189 of 365 days2005: Moderate 142 of 365 days2005: Unhealthy for Sensitive Groups 29 of 365 days2005: Unhealthy 5 of 365 days20052006: Good 226 of 365 days2006: Moderate 125 of 365 days2006: Unhealthy for Sensitive Groups 13 of 365 days2006: Unhealthy 1 of 365 days2007: Good 204 of 365 days2007: Moderate 124 of 365 days2007: Unhealthy for Sensitive Groups 29 of 365 days2007: Unhealthy 8 of 365 days2008: Good 225 of 366 days2008: Moderate 124 of 366 days2008: Unhealthy for Sensitive Groups 16 of 366 days2008: Unhealthy 1 of 366 days2009: Good 129 of 365 days2009: Moderate 232 of 365 days2009: Unhealthy for Sensitive Groups 4 of 365 days2010: Good 80 of 365 days2010: Moderate 267 of 365 days2010: Unhealthy for Sensitive Groups 18 of 365 days20102011: Good 194 of 365 days2011: Moderate 164 of 365 days2011: Unhealthy for Sensitive Groups 7 of 365 days2012: Good 154 of 366 days2012: Moderate 210 of 366 days2012: Unhealthy for Sensitive Groups 1 of 366 days2012: Unhealthy 1 of 366 days2013: Good 281 of 365 days2013: Moderate 82 of 365 days2013: Unhealthy for Sensitive Groups 2 of 365 days2014: Good 289 of 365 days2014: Moderate 75 of 365 days2014: Unhealthy for Sensitive Groups 1 of 365 days2015: Good 96 of 365 days2015: Moderate 268 of 365 days2015: Unhealthy for Sensitive Groups 1 of 365 days20152016: Good 158 of 366 days2016: Moderate 207 of 366 days2016: Unhealthy for Sensitive Groups 1 of 366 days2017: Good 221 of 365 days2017: Moderate 144 of 365 days2018: Good 200 of 365 days2018: Moderate 164 of 365 days2018: Unhealthy for Sensitive Groups 1 of 365 days2019: Good 199 of 363 days2019: Moderate 161 of 363 days2019: Unhealthy for Sensitive Groups 3 of 363 days2020: Good 193 of 361 days2020: Moderate 165 of 361 days2020: Unhealthy for Sensitive Groups 3 of 361 days20202021: Good 223 of 356 days2021: Moderate 130 of 356 days2021: Unhealthy for Sensitive Groups 3 of 356 days2022: Good 231 of 362 days2022: Moderate 128 of 362 days2022: Unhealthy for Sensitive Groups 3 of 362 days2023: Good 209 of 348 days2023: Moderate 131 of 348 days2023: Unhealthy for Sensitive Groups 5 of 348 days2023: Unhealthy 2 of 348 days2023: Very Unhealthy 1 of 348 days2024: Good 224 of 341 days2024: Moderate 116 of 341 days2024: Unhealthy for Sensitive Groups 1 of 341 days2025: Good 232 of 365 days2025: Moderate 130 of 365 days2025: Unhealthy for Sensitive Groups 3 of 365 days2025
  • 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 and 90th-percentile daily AQI, by year0501001501980: 90th percentile AQI 1151981: 90th percentile AQI 901982: 90th percentile AQI 1001983: 90th percentile AQI 1261984: 90th percentile AQI 971985: 90th percentile AQI 971986: 90th percentile AQI 971987: 90th percentile AQI 1011988: 90th percentile AQI 1471989: 90th percentile AQI 1011990: 90th percentile AQI 971991: 90th percentile AQI 1401992: 90th percentile AQI 581993: 90th percentile AQI 901994: 90th percentile AQI 921995: 90th percentile AQI 871996: 90th percentile AQI 1001997: 90th percentile AQI 771998: 90th percentile AQI 1121999: 90th percentile AQI 1082000: 90th percentile AQI 902001: 90th percentile AQI 1082002: 90th percentile AQI 1082003: 90th percentile AQI 882004: 90th percentile AQI 872005: 90th percentile AQI 1002006: 90th percentile AQI 802007: 90th percentile AQI 1012008: 90th percentile AQI 822009: 90th percentile AQI 762010: 90th percentile AQI 902011: 90th percentile AQI 752012: 90th percentile AQI 782013: 90th percentile AQI 612014: 90th percentile AQI 602015: 90th percentile AQI 782016: 90th percentile AQI 652017: 90th percentile AQI 632018: 90th percentile AQI 672019: 90th percentile AQI 652020: 90th percentile AQI 632021: 90th percentile AQI 672022: 90th percentile AQI 622023: 90th percentile AQI 742024: 90th percentile AQI 702025: 90th percentile AQI 671980: Median AQI 511981: Median AQI 321982: Median AQI 341983: Median AQI 331984: Median AQI 311985: Median AQI 361986: Median AQI 341987: Median AQI 291988: Median AQI 311989: Median AQI 351990: Median AQI 351991: Median AQI 361992: Median AQI 301993: Median AQI 321994: Median AQI 341995: Median AQI 311996: Median AQI 321997: Median AQI 281998: Median AQI 301999: Median AQI 662000: Median AQI 642001: Median AQI 642002: Median AQI 622003: Median AQI 602004: Median AQI 592005: Median AQI 492006: Median AQI 412007: Median AQI 462008: Median AQI 442009: Median AQI 552010: Median AQI 632011: Median AQI 462012: Median AQI 552013: Median AQI 322014: Median AQI 352015: Median AQI 572016: Median AQI 522017: Median AQI 462018: Median AQI 482019: Median AQI 482020: Median AQI 482021: Median AQI 452022: Median AQI 432023: Median AQI 462024: Median AQI 442025: Median AQI 441980198519901995200020052010201520202025
  • 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.

PollutantDays as main pollutantShare of monitored days
Fine particles (PM2.5)21158%
Ozone15442%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536523213030004467126PM2.5
202434122411610004470105PM2.5
202334820913152104674230PM2.5
202236223112830004362133PM2.5
202135622313030004567105PM2.5
202036119316530004863114PM2.5
201936319916130004865115PM2.5
201836520016410004867105PM2.5
20173652211440000466397PM2.5
201636615820710005265112PM2.5
20153659626810005778135PM2.5
20143652897510003560107Ozone
20133652818220003261146Ozone
201236615421011005578151PM2.5
201136519416470004675150PM2.5
201036580267180006390140PM2.5
200936512923240005576105PM2.5
2008366225124161004482164Ozone
20073652041242980046101179Ozone
2006365226125131004180184Ozone
20053651891422950049100177Ozone
200436691257162005987154PM2.5
200336565278183106088204PM2.5
20023656625522202062108207PM2.5
20013656425533121064108203PM2.5
200036667273233006490185PM2.5
19993655526237110066108179PM2.5
19983652615833121030112209Ozone
199736529849144002877182Ozone
1996366288432690032100185Ozone
1995365287551310003187185Ozone
199436528749272003492154Ozone
199336527957209003290185Ozone
199236631931124003058182Ozone
19913652515830242036140215Ozone
199036528549255103597207Ozone
19893652646423113035101213Ozone
198836627231292410031147249Ozone
19873652765225111029101215Ozone
198636527060287003497182Ozone
198536527260276003697197Ozone
198436628055238003197182Ozone
19833652645133125033126207Ozone
19823642785322101034100202Ozone
1981358293381510203290232Ozone
198036418213331162051115205CO

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

All monitored counties in Ohio

Source: U.S. EPA AirData, “Annual AQI by County” files for 1980–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem