Counties in Kentucky by highest daily Air Quality Index (US EPA)

Campbell County had the highest highest daily Air Quality Index (US EPA) of 36 counties in 1996, at 209. Whitley County had the lowest, at 42. The median was 161. Source: the U.S. Environmental Protection Agency.

Highest209Campbell County

Lowest42Whitley County

Median16136 counties

Map of counties, 1996

Under 100
100 to 150
150 to 160
160 to 170
170 to 180
180 and over
No data

index, 1996. Hatched areas have no value for this period. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 1996

index. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12.

Full ranking

Rank	Counties	1996 index	Change on 1995
1	Campbell County	209	+7
1	Morgan County	209	+4
3	Jefferson County	202	+5
4	Kenton County	200	-10
5	Oldham County	197	+31
6	Boone County	187	-8
7	Boyd County	177	-18
7	Daviess County	177	0
9	Henderson County	174	-8
9	Washington County	174	-5
11	Edmonson County	172	-15
11	Greenup County	172	-2
13	Bullitt County	169	-31
14	Hardin County	166	-40
14	Livingston County	166	0
14	Simpson County	166	-13
17	Jessamine County	164	-33
18	Hancock County	161	-29
18	Trigg County	161	-11
20	Fayette County	159	-38
21	Bell County	151	0
21	Graves County	151	+25
21	Scott County	151	-34
24	McLean County	150	-45
25	Christian County	147	-3
26	Perry County	143	-16
27	McCracken County	129	-21
27	Pike County	129	-71
29	Pulaski County	115	-85
30	Lawrence County	108	-96
31	Marshall County	83	+24
32	Floyd County	66	-9
33	Harlan County	62	+1
34	Madison County	51	-7
35	Warren County	45	-3
36	Whitley County	42	-20

Other periods

About this ranking

Highest daily Air Quality Index (AQI) value recorded in a US county during the year, from the EPA AirData annual summaries. Values above 500 are beyond the AQI scale and are published as EPA computes them.

A single day decides the value, so one wildfire or dust event can set it. Dust from the dry Owens Lake bed puts Inyo and Mono counties in California in the thousands. United States counties with air quality monitors only, about 1,000 of some 3,100 in recent years; a county without monitors has no value. The number of days with an AQI differs between counties because some monitors run only in the ozone season.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. 19 counties with data in other periods have no value for 1996 and are left out rather than filled from another source. Equal values share a rank.

How to cite

U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Environmental Protection Agency. (2026). EPA AirData annual AQI by county: highest daily AQI (Counties in Kentucky by highest daily Air Quality Index (US EPA), 1996) [Data set]. Retrieved October 12, 2026, from https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual

MLA 9

EPA AirData annual AQI by county: highest daily AQI, Counties in Kentucky by highest daily Air Quality Index (US EPA), 1996. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/kentucky-counties?period=1996. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: highest daily AQI. Counties in Kentucky by highest daily Air Quality Index (US EPA), 1996. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/kentucky-counties?period=1996.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: highest daily AQI, Counties in Kentucky by highest daily Air Quality Index (US EPA), 1996 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/rankings/highest-daily-air-quality-index/kentucky-counties?period=1996 (Accessed: 12 October 2026).

BibTeX

@misc{environmental_counties_in_kentucky_by_1996,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: highest daily AQI: Counties in Kentucky by highest daily Air Quality Index (US EPA), 1996}},
  year = {2026},
  howpublished = {Data set},
  url = {https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/kentucky-counties?period=1996. Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download\_files.html\#Annual. Retrieved 2026-10-12.},
}

RIS

TY  - DATA
AU  - U.S. Environmental Protection Agency
TI  - EPA AirData annual AQI by county: highest daily AQI: Counties in Kentucky by highest daily Air Quality Index (US EPA), 1996
PY  - 2026
DA  - 2026/07/13
PB  - U.S. Environmental Protection Agency
DB  - Invokely
UR  - https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual
L2  - https://invokely.ai/rankings/highest-daily-air-quality-index/kentucky-counties?period=1996
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/kentucky-counties?period=1996.
N1  - Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
ER  -

Embed this chart

Paste this code into a web page or a blog post. The chart shows the latest figures as they are published, with the source and a link back to this page.

Embed code

<iframe src="https://invokely.ai/embed/rankings/highest-daily-air-quality-index/kentucky-counties?period=1996" width="760" height="500" title="Counties in Kentucky by highest daily Air Quality Index (US EPA), 1996, chart from Invokely" loading="lazy" style="border:0;width:100%;max-width:760px" referrerpolicy="strict-origin-when-cross-origin"></iframe>

Sites that read oEmbed links, such as WordPress, can show the chart when you paste the link to this page.

Use this data in your AI agent

Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:

Rank Counties in Kentucky by highest daily Air Quality Index (US EPA) using official data, and cite the source.

rank_places {"indicator":"aqi_max","level":"province","within":"Kentucky","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=aqi_max&level=province&within=Kentucky&limit=10

Connect Claude, ChatGPT or Cursor in one step. The trial answers 25 calls a day without an account.

Questions

Which county has the highest highest daily Air Quality Index (US EPA)?

Campbell County, with 209 in 1996, according to the U.S. Environmental Protection Agency.

Which county has the lowest highest daily Air Quality Index (US EPA)?

Whitley County, with 42 in 1996.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12. 19 counties have no value for 1996 and are not ranked.