Kentucky · County air quality · 2025

Hancock County, Kentucky

Median AQI 43 (Good). 82.6% of monitored days rated Good, direct from EPA Air Quality System stations.

43
Median AQI
82.6%
Good-air days
0
Unhealthy days
63%
Cleaner than US counties

Hancock County's 2025 annual median AQI is 43 (Good), with 82.6% Good days

According to the U.S. EPA Air Quality System, Hancock County, Kentucky posted a 2025 median AQI of 43 (Good) across 242 monitored days, with 82.6% rated Good and 0 unhealthy or worse. This is an annual comparison, not today's advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US
Hancock County's 82.6% Good-day share places it cleaner than 63% of US counties in 2025.
Closest median-AQI peer
Ashtabula County (81.2% Good, median AQI 43) is the closest nationwide median-AQI peer to Hancock County.
2020–2025 trend
Hancock County's floor-qualifying Good-day share is worsening from 2020 to 2025 (95.1% → 82.6%).
Median AQI
Median AQI: 43

According to the 2025 EPA AQS county release on PlainAirData, Hancock County, Kentucky ranks #631 of 951 by median AQI (43) and #355 by good-day share (82.6%). Ponce County, Puerto Rico is #1 of 951 by median AQI (3, 91.4% Good days) at good-day-share #159 ≠ largest of 7 at 100.0% Good days #1 by good-day share (100.0%, median AQI 9) at median-AQI #7.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Hancock County's Good-day share fell from 87.3% to 82.6% between the 2024 and 2025 EPA annual releases, a change of -4.7 percentage points.

Compared against 229 monitored days in 2024 and 242 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Data updated August 2026

Hancock County AQI category distribution Stacked-segment bar showing the share of monitored days that fell in each EPA AQI category, Good, Moderate, USG, Unhealthy, Very Unhealthy, Hazardous, with median AQI marker. AQI category distribution 242 monitored days G M Median AQI 43 0 50 100 150 200 300 500 Hancock County
  • Good · 200 d · 82.6%
  • Moderate · 42 d · 17.4%

How did Hancock County's air break down in 2025?

Across 242 monitored days, 200 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 97 (Moderate).

EPA AQS →
Hancock County, Good days share 82.6%
National avg

Share of monitored days at AQI 0-50 (Good band).

Hancock County, Unhealthy-or-worse share 0.0%
National avg

Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).

Where Hancock County sits nationally

COUNT-derived placement among 951 US counties with at least 100 monitored days in 2025. Hancock County's Good-day share is 82.6% - cleaner than 63% of that comparison set.

Hancock County Good-day share vs. every US county

Share of monitored days in the Good band (AQI 0–50) - EPA AQS annual release

82.6% Cleaner than 63% higher than 63% of 951 US counties

0.0%–5.0%: 0 US counties (0%). Below this entry. 5.0%–10.0%: 1 US counties (0%). Below this entry. 10.0%–15.0%: 4 US counties (0%). Below this entry. 15.0%–20.0%: 4 US counties (0%). Below this entry. 20.0%–25.0%: 1 US counties (0%). Below this entry. 25.0%–30.0%: 5 US counties (1%). Below this entry. 30.0%–35.0%: 9 US counties (1%). Below this entry. 35.0%–40.0%: 4 US counties (0%). Below this entry. 40.0%–45.0%: 16 US counties (2%). Below this entry. 45.0%–50.0%: 16 US counties (2%). Below this entry. 50.0%–55.0%: 32 US counties (3%). Below this entry. 55.0%–60.0%: 50 US counties (5%). Below this entry. 60.0%–65.0%: 77 US counties (8%). Below this entry. 65.0%–70.0%: 93 US counties (10%). Below this entry. 70.0%–75.0%: 109 US counties (11%). Below this entry. 75.0%–80.0%: 114 US counties (12%). Below this entry. 80.0%–85.0%: 123 US counties (13%). This entry sits in this band. 85.0%–90.0%: 99 US counties (10%). Above this entry. 90.0%–95.0%: 117 US counties (12%). Above this entry. 95.0%–100.0%: 70 US counties (7%). Above this entry. 100.0%–105.0%: 7 US counties (1%). Above this entry. This county 0.0% 100% every floor-qualified US county, bucketed by value

Each bar is a band; taller bars hold more US counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source U.S. Environmental Protection Agency, Air Quality System (AQS) · 2025

Pollutant Breakdown

Days where each pollutant was the primary driver of AQI readings in Hancock County.

Hancock County, Kentucky criteria pollutant distribution Stratified-band visualization showing the share of monitored days each criteria pollutant (PM2.5, PM10, O3, NO2, CO) was the primary AQI driver. Ozone · 100.0% 0% 25% 50% 75% 100% Hancock County, Kentucky · 242 monitored days Criteria pollutant column
  • Ozone · 242 days · 100.0%

2024 daily-monitor rhythm in Hancock County

Month-by-month median AQI from EPA day-level county monitors (229 reported days in 2024). May posted the highest typical readings (median AQI 45, peak 64); Mar was cleanest at median 38.

0 10 20 30 40 50 Mar Apr May Jun Jul Aug Sep Oct 38 43 45 45 45 44 39 43
Hancock County median daily AQI by calendar month (2024, EPA daily county file)

Five-year seasonal record

EPA day-level county files · 2020–2024

1,203 daily readings show a recurring local pattern: Jun has the highest matched-month median AQI (47), while Oct is lowest (34). Each cell is that month’s median daily AQI, not a current-air forecast.

JanFebMarAprMayJunJulAugSepOctNovDec
2020 --3339374541353729--
2021 --3942393740353931--
2022 --4039404945403534--
2023 --3844435844394235--
2024 --3843454545443943--

Lower AQI is better. The colors summarize EPA AQI bands; gaps mean the county had no day-level record for that month.

Health Impact Assessment

Good

Hancock County's air quality is rated Good based on 82.6% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 82.6% of monitored days in 2025, with a median AQI of 43. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is Ozone, driving AQI on 242 of 242 monitored days.

5-Year Air Quality Trend

Air quality is worsening in Hancock County. Highest Good-day share: 2020 (95.1%, 233 of 245 monitored days).

Year Good Moderate USG Unhealthy Median AQI
2020 233 12 0 0 37
2021 220 21 0 0 38
2022 219 23 1 0 40
2023 201 38 6 0 42
2024 200 29 0 0 44
2025 200 42 0 0 43

How does Hancock County compare?

How Hancock County compares

Good-day share better than typical
Hancock County 82.6%
Ashtabula County, Ohio 81.2%
Typical US county 76.0%
Median AQI worse than typical
Hancock County 43
Ashtabula County, Ohio 43
Typical US county 39
Unhealthy days / yr better than typical
Hancock County 0
Ashtabula County, Ohio 0
Typical US county 1

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.

Informational only, not professional advice. Data from EPA AQS. See our disclaimer. Spotted a figure that looks wrong? Report a correction.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Hancock County, Kentucky · 2020–2025

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Download this county's annual AQI row as CSV , with the same EPA fields and denominator shown on this page.

Every figure on PlainAirData is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.