EnviroNearby

Bell County, Kentucky air quality history

Daily Air Quality Index summaries from EPA monitors in Bell, Kentucky, 1988–2025.

67%
Good days in 2025
42
Median daily AQI, 2025
1
Days above 100 in 2025
361
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Bell, Kentucky on 361 days. 242 of those days (67%) were in the Good range, and the median daily AQI was 42. That median is higher than the typical monitored county in Kentucky (median 39 across 25 counties), and about the same as the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 258 days. Across the years with fuller monitoring, the share of Good days fell: an average of 87% in 1991–1993 versus 62% in 2023–2025.

Years with fewer than 120 monitored days (1988, 1989, 1990) 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.

Share of monitored days in each AQI category, by year0%25%50%75%100%1988: Good 20 of 23 days1988: Moderate 3 of 23 days19881989: Good 47 of 61 days1989: Moderate 14 of 61 days1990: Good 52 of 58 days1990: Moderate 6 of 58 days1991: Good 168 of 173 days1991: Moderate 5 of 173 days1992: Good 319 of 366 days1992: Moderate 43 of 366 days1992: Unhealthy for Sensitive Groups 4 of 366 days1993: Good 279 of 365 days1993: Moderate 79 of 365 days1993: Unhealthy for Sensitive Groups 7 of 365 days19931994: Good 303 of 365 days1994: Moderate 57 of 365 days1994: Unhealthy for Sensitive Groups 4 of 365 days1994: Unhealthy 1 of 365 days1995: Good 279 of 365 days1995: Moderate 69 of 365 days1995: Unhealthy for Sensitive Groups 16 of 365 days1995: Unhealthy 1 of 365 days1996: Good 318 of 366 days1996: Moderate 40 of 366 days1996: Unhealthy for Sensitive Groups 7 of 366 days1996: Unhealthy 1 of 366 days1997: Good 286 of 365 days1997: Moderate 69 of 365 days1997: Unhealthy for Sensitive Groups 10 of 365 days1998: Good 274 of 365 days1998: Moderate 73 of 365 days1998: Unhealthy for Sensitive Groups 14 of 365 days1998: Unhealthy 4 of 365 days19981999: Good 241 of 364 days1999: Moderate 94 of 364 days1999: Unhealthy for Sensitive Groups 28 of 364 days1999: Unhealthy 1 of 364 days2000: Good 230 of 366 days2000: Moderate 99 of 366 days2000: Unhealthy for Sensitive Groups 32 of 366 days2000: Unhealthy 5 of 366 days2001: Good 193 of 312 days2001: Moderate 99 of 312 days2001: Unhealthy for Sensitive Groups 18 of 312 days2001: Unhealthy 2 of 312 days2002: Good 137 of 264 days2002: Moderate 93 of 264 days2002: Unhealthy for Sensitive Groups 26 of 264 days2002: Unhealthy 8 of 264 days2003: Good 160 of 265 days2003: Moderate 96 of 265 days2003: Unhealthy for Sensitive Groups 9 of 265 days20032004: Good 182 of 263 days2004: Moderate 79 of 263 days2004: Unhealthy for Sensitive Groups 2 of 263 days2005: Good 124 of 234 days2005: Moderate 99 of 234 days2005: Unhealthy for Sensitive Groups 11 of 234 days2006: Good 171 of 267 days2006: Moderate 95 of 267 days2006: Unhealthy for Sensitive Groups 1 of 267 days2007: Good 86 of 264 days2007: Moderate 141 of 264 days2007: Unhealthy for Sensitive Groups 33 of 264 days2007: Unhealthy 4 of 264 days2008: Good 137 of 263 days2008: Moderate 121 of 263 days2008: Unhealthy for Sensitive Groups 5 of 263 days20082009: Good 202 of 264 days2009: Moderate 62 of 264 days2010: Good 158 of 264 days2010: Moderate 99 of 264 days2010: Unhealthy for Sensitive Groups 7 of 264 days2011: Good 190 of 263 days2011: Moderate 73 of 263 days2012: Good 151 of 259 days2012: Moderate 104 of 259 days2012: Unhealthy for Sensitive Groups 4 of 259 days2013: Good 225 of 264 days2013: Moderate 39 of 264 days20132014: Good 208 of 266 days2014: Moderate 58 of 266 days2015: Good 227 of 261 days2015: Moderate 34 of 261 days2016: Good 230 of 261 days2016: Moderate 29 of 261 days2016: Unhealthy for Sensitive Groups 1 of 261 days2016: Unhealthy 1 of 261 days2017: Good 231 of 263 days2017: Moderate 32 of 263 days2018: Good 224 of 256 days2018: Moderate 32 of 256 days20182019: Good 238 of 263 days2019: Moderate 25 of 263 days2020: Good 242 of 263 days2020: Moderate 21 of 263 days2021: Good 164 of 364 days2021: Moderate 198 of 364 days2021: Unhealthy for Sensitive Groups 2 of 364 days2022: Good 197 of 365 days2022: Moderate 168 of 365 days2023: Good 185 of 365 days2023: Moderate 177 of 365 days2023: Unhealthy for Sensitive Groups 3 of 365 days20232024: Good 244 of 365 days2024: Moderate 121 of 365 days2025: Good 242 of 361 days2025: Moderate 118 of 361 days2025: Unhealthy for Sensitive Groups 1 of 361 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 year0501001501988: 90th percentile AQI 531989: 90th percentile AQI 541990: 90th percentile AQI 511991: 90th percentile AQI 381992: 90th percentile AQI 541993: 90th percentile AQI 741994: 90th percentile AQI 611995: 90th percentile AQI 801996: 90th percentile AQI 581997: 90th percentile AQI 711998: 90th percentile AQI 841999: 90th percentile AQI 972000: 90th percentile AQI 1012001: 90th percentile AQI 872002: 90th percentile AQI 1082003: 90th percentile AQI 772004: 90th percentile AQI 692005: 90th percentile AQI 832006: 90th percentile AQI 712007: 90th percentile AQI 1082008: 90th percentile AQI 802009: 90th percentile AQI 632010: 90th percentile AQI 802011: 90th percentile AQI 652012: 90th percentile AQI 762013: 90th percentile AQI 542014: 90th percentile AQI 592015: 90th percentile AQI 542016: 90th percentile AQI 522017: 90th percentile AQI 522018: 90th percentile AQI 522019: 90th percentile AQI 502020: 90th percentile AQI 482021: 90th percentile AQI 682022: 90th percentile AQI 642023: 90th percentile AQI 672024: 90th percentile AQI 602025: 90th percentile AQI 591988: Median AQI 261989: Median AQI 341990: Median AQI 271991: Median AQI 251992: Median AQI 341993: Median AQI 411994: Median AQI 381995: Median AQI 351996: Median AQI 321997: Median AQI 341998: Median AQI 351999: Median AQI 392000: Median AQI 442001: Median AQI 452002: Median AQI 502003: Median AQI 462004: Median AQI 442005: Median AQI 492006: Median AQI 462007: Median AQI 642008: Median AQI 502009: Median AQI 432010: Median AQI 482011: Median AQI 442012: Median AQI 472013: Median AQI 402014: Median AQI 422015: Median AQI 392016: Median AQI 392017: Median AQI 402018: Median AQI 392019: Median AQI 402020: Median AQI 342021: Median AQI 522022: Median AQI 482023: Median AQI 492024: Median AQI 442025: Median AQI 42198819931998200320082013201820232025
  • 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)25871%
Ozone10329%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536124211810004259101PM2.5
20243652441210000446088PM2.5
202336518517730004967131PM2.5
20223651971680000486491PM2.5
202136416419820005268112PM2.5
2020263242210000344874Ozone
2019263238250000405077Ozone
2018256224320000395284Ozone
2017263231320000405280Ozone
20162612302911003952165Ozone
2015261227340000395477Ozone
2014266208580000425993Ozone
2013264225390000405480Ozone
201225915110440004776133Ozone
2011263190730000446597Ozone
20102641589970004880115Ozone
2009264202620000436393Ozone
200826313712150005080126Ozone
2007264861413340064108176Ozone
20062671719510004671101Ozone
200523412499110004983136Ozone
20042631827920004469115Ozone
20032651609690004677147Ozone
2002264137932680050108182Ozone
200131219399182004587159Ozone
2000366230993250044101190Ozone
199936424194281003997151Ozone
199836527473144003584174Ozone
199736528669100003471122Ozone
19963663184071003258151Ozone
199536527969161003580151Ozone
19943653035741003861174Ozone
19933652797970004174126Ozone
19923663194340003454129CO
199117316850000253866CO
1990585260000275158PM10
19896147140000345468PM10
1988232030000265360PM10

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 Kentucky with a similar median AQI in 2025

All monitored counties in Kentucky

Source: U.S. EPA AirData, “Annual AQI by County” files for 1988–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem