EnviroNearby

Bullitt County, Kentucky air quality history

Daily Air Quality Index summaries from EPA monitors in Bullitt, Kentucky, 1980–2025.

88%
Good days in 2025
39
Median daily AQI, 2025
0
Days above 100 in 2025
232
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Bullitt, Kentucky on 232 days. 205 of those days (88%) were in the Good range, and the median daily AQI was 39. That median is about the same as 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 ozone on 232 days. Across the years with fuller monitoring, the share of Good days held roughly steady: an average of 85% in 1984–1986 versus 83% in 2023–2025.

EPA did not report an AQI for every day of 2025 here (232 of 365 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.

Years with fewer than 120 monitored days (1980, 1981) 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%1980: Good 82 of 89 days1980: Moderate 7 of 89 days19801981: Good 19 of 19 days1984: Good 147 of 167 days1984: Moderate 16 of 167 days1984: Unhealthy for Sensitive Groups 4 of 167 days1985: Good 158 of 204 days1985: Moderate 37 of 204 days1985: Unhealthy for Sensitive Groups 8 of 204 days1985: Unhealthy 1 of 204 days1986: Good 188 of 209 days1986: Moderate 16 of 209 days1986: Unhealthy for Sensitive Groups 4 of 209 days1986: Unhealthy 1 of 209 days1987: Good 128 of 214 days1987: Moderate 66 of 214 days1987: Unhealthy for Sensitive Groups 16 of 214 days1987: Unhealthy 4 of 214 days19871988: Good 133 of 211 days1988: Moderate 46 of 211 days1988: Unhealthy for Sensitive Groups 20 of 211 days1988: Unhealthy 9 of 211 days1988: Very Unhealthy 3 of 211 days1989: Good 189 of 208 days1989: Moderate 18 of 208 days1989: Unhealthy for Sensitive Groups 1 of 208 days1990: Good 153 of 197 days1990: Moderate 28 of 197 days1990: Unhealthy for Sensitive Groups 14 of 197 days1990: Unhealthy 2 of 197 days1991: Good 167 of 220 days1991: Moderate 42 of 220 days1991: Unhealthy for Sensitive Groups 8 of 220 days1991: Unhealthy 3 of 220 days1992: Good 256 of 289 days1992: Moderate 33 of 289 days19921993: Good 270 of 347 days1993: Moderate 62 of 347 days1993: Unhealthy for Sensitive Groups 9 of 347 days1993: Unhealthy 6 of 347 days1994: Good 294 of 362 days1994: Moderate 50 of 362 days1994: Unhealthy for Sensitive Groups 16 of 362 days1994: Unhealthy 2 of 362 days1995: Good 272 of 364 days1995: Moderate 70 of 364 days1995: Unhealthy for Sensitive Groups 18 of 364 days1995: Unhealthy 4 of 364 days1996: Good 286 of 364 days1996: Moderate 58 of 364 days1996: Unhealthy for Sensitive Groups 18 of 364 days1996: Unhealthy 2 of 364 days1997: Good 223 of 295 days1997: Moderate 48 of 295 days1997: Unhealthy for Sensitive Groups 20 of 295 days1997: Unhealthy 3 of 295 days1997: Very Unhealthy 1 of 295 days19971998: Good 246 of 365 days1998: Moderate 79 of 365 days1998: Unhealthy for Sensitive Groups 30 of 365 days1998: Unhealthy 10 of 365 days1999: Good 186 of 357 days1999: Moderate 114 of 357 days1999: Unhealthy for Sensitive Groups 46 of 357 days1999: Unhealthy 11 of 357 days2000: Good 212 of 362 days2000: Moderate 124 of 362 days2000: Unhealthy for Sensitive Groups 23 of 362 days2000: Unhealthy 3 of 362 days2001: Good 185 of 358 days2001: Moderate 135 of 358 days2001: Unhealthy for Sensitive Groups 36 of 358 days2001: Unhealthy 2 of 358 days2002: Good 212 of 364 days2002: Moderate 123 of 364 days2002: Unhealthy for Sensitive Groups 21 of 364 days2002: Unhealthy 8 of 364 days20022003: Good 241 of 362 days2003: Moderate 114 of 362 days2003: Unhealthy for Sensitive Groups 7 of 362 days2004: Good 250 of 357 days2004: Moderate 105 of 357 days2004: Unhealthy for Sensitive Groups 1 of 357 days2004: Unhealthy 1 of 357 days2005: Good 206 of 358 days2005: Moderate 131 of 358 days2005: Unhealthy for Sensitive Groups 21 of 358 days2006: Good 226 of 363 days2006: Moderate 132 of 363 days2006: Unhealthy for Sensitive Groups 5 of 363 days2007: Good 89 of 324 days2007: Moderate 215 of 324 days2007: Unhealthy for Sensitive Groups 20 of 324 days20072008: Good 157 of 284 days2008: Moderate 124 of 284 days2008: Unhealthy for Sensitive Groups 2 of 284 days2008: Unhealthy 1 of 284 days2009: Good 182 of 283 days2009: Moderate 101 of 283 days2010: Good 119 of 284 days2010: Moderate 157 of 284 days2010: Unhealthy for Sensitive Groups 8 of 284 days2011: Good 148 of 266 days2011: Moderate 114 of 266 days2011: Unhealthy for Sensitive Groups 3 of 266 days2011: Unhealthy 1 of 266 days2012: Good 183 of 245 days2012: Moderate 56 of 245 days2012: Unhealthy for Sensitive Groups 5 of 245 days2012: Unhealthy 1 of 245 days20122013: Good 222 of 243 days2013: Moderate 20 of 243 days2013: Unhealthy for Sensitive Groups 1 of 243 days2014: Good 194 of 222 days2014: Moderate 27 of 222 days2014: Unhealthy for Sensitive Groups 1 of 222 days2015: Good 215 of 242 days2015: Moderate 25 of 242 days2015: Unhealthy for Sensitive Groups 2 of 242 days2016: Good 202 of 236 days2016: Moderate 33 of 236 days2016: Unhealthy for Sensitive Groups 1 of 236 days2017: Good 208 of 233 days2017: Moderate 25 of 233 days20172018: Good 196 of 233 days2018: Moderate 35 of 233 days2018: Unhealthy for Sensitive Groups 2 of 233 days2019: Good 214 of 243 days2019: Moderate 29 of 243 days2020: Good 224 of 240 days2020: Moderate 15 of 240 days2020: Unhealthy for Sensitive Groups 1 of 240 days2021: Good 212 of 237 days2021: Moderate 24 of 237 days2021: Unhealthy for Sensitive Groups 1 of 237 days2022: Good 212 of 239 days2022: Moderate 26 of 239 days2022: Unhealthy for Sensitive Groups 1 of 239 days20222023: Good 188 of 238 days2023: Moderate 44 of 238 days2023: Unhealthy for Sensitive Groups 6 of 238 days2024: Good 201 of 244 days2024: Moderate 42 of 244 days2024: Unhealthy for Sensitive Groups 1 of 244 days2025: Good 205 of 232 days2025: Moderate 27 of 232 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 501981: 90th percentile AQI 431984: 90th percentile AQI 541985: 90th percentile AQI 711986: 90th percentile AQI 511987: 90th percentile AQI 971988: 90th percentile AQI 1221989: 90th percentile AQI 501990: 90th percentile AQI 1001991: 90th percentile AQI 801992: 90th percentile AQI 541993: 90th percentile AQI 771994: 90th percentile AQI 771995: 90th percentile AQI 841996: 90th percentile AQI 841997: 90th percentile AQI 901998: 90th percentile AQI 1011999: 90th percentile AQI 1152000: 90th percentile AQI 892001: 90th percentile AQI 1012002: 90th percentile AQI 872003: 90th percentile AQI 742004: 90th percentile AQI 662005: 90th percentile AQI 872006: 90th percentile AQI 772007: 90th percentile AQI 902008: 90th percentile AQI 742009: 90th percentile AQI 642010: 90th percentile AQI 772011: 90th percentile AQI 742012: 90th percentile AQI 772013: 90th percentile AQI 502014: 90th percentile AQI 512015: 90th percentile AQI 542016: 90th percentile AQI 582017: 90th percentile AQI 512018: 90th percentile AQI 582019: 90th percentile AQI 512020: 90th percentile AQI 482021: 90th percentile AQI 512022: 90th percentile AQI 512023: 90th percentile AQI 712024: 90th percentile AQI 582025: 90th percentile AQI 541980: Median AQI 291981: Median AQI 311984: Median AQI 361985: Median AQI 391986: Median AQI 311987: Median AQI 441988: Median AQI 441989: Median AQI 311990: Median AQI 371991: Median AQI 381992: Median AQI 341993: Median AQI 361994: Median AQI 361995: Median AQI 361996: Median AQI 351997: Median AQI 351998: Median AQI 381999: Median AQI 492000: Median AQI 452001: Median AQI 492002: Median AQI 442003: Median AQI 402004: Median AQI 412005: Median AQI 462006: Median AQI 432007: Median AQI 592008: Median AQI 482009: Median AQI 442010: Median AQI 542011: Median AQI 482012: Median AQI 432013: Median AQI 372014: Median AQI 382015: Median AQI 392016: Median AQI 392017: Median AQI 392018: Median AQI 382019: Median AQI 412020: Median AQI 372021: Median AQI 372022: Median AQI 402023: Median AQI 442024: Median AQI 432025: Median AQI 391980198719921997200220072012201720222025
  • 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
Ozone232100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025232205270000395490Ozone
20242442014210004358105Ozone
20232381884460004471126Ozone
20222392122610004051101Ozone
20212372122410003751143Ozone
20202402241510003748115Ozone
2019243214290000415193Ozone
20182331963520003858150Ozone
2017233208250000395197Ozone
20162362023310003958122Ozone
20152422152520003954108Ozone
20142221942710003851112Ozone
20132432222010003750105Ozone
20122451835651004377151Ozone
201126614811431004874187Ozone
201028411915780005477119Ozone
200928318210100004464100Ozone
200828415712421004874154Ozone
200732489215200005990147PM2.5
200636322613250004377126Ozone
2005358206131210004687143Ozone
200435725010511004166192Ozone
200336224111470004074119Ozone
2002364212123218004487197Ozone
20013581851353620049101187Ozone
2000362212124233004589161Ozone
199935718611446110049115187Ozone
19983652467930100038101192Ozone
199729522348203103590206Ozone
199636428658182003584169NO2
199536427270184003684200Ozone
199436229450162003677159NO2
19933472706296003677177NO2
19922892563300003454100Ozone
19912201674283003880164Ozone
1990197153281420037100190Ozone
19892081891810003150112Ozone
1988211133462093044122215Ozone
198721412866164004497185Ozone
19862091881641003151151Ozone
19852041583781003971159Ozone
19841671471640003654122Ozone
1981191900000314345NO2
1980898270000295074Ozone

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 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