Metro area air quality · 2025

York-Hanover, PA

Median AQI 45 (Good). 65.6% of monitored days rated Good across this metro's EPA monitoring network.

45
Median AQI
65.6%
Good-air days
0
Unhealthy days
35%
Cleaner than US metros

Aggregated from EPA Air Quality System (2025), 212 monitored days. EPA AQS →

The verdict

The York-Hanover, PA metro runs good on the EPA scale, more polluted than the median US metro, a median AQI of 45 with 65.6% of 212 monitored days in the Good band.

45
median AQI · Good
65.6%
days rated Good
35%
cleaner than US metros
101
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Insights: York-Hanover, PA metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 45 over 212 measured days in 2025, which corresponds to a Good band and a Moderate metro-wide health grade. The monitored-day split lands at 139 Good days (66%), 72 Moderate (34%), and 1 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 66 while the highest single-day reading hit 101 (USG). Metro residents averaged roughly 19.7 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, good days shifted by -82 and the median AQI moved -1 points, which classifies the multi-year trajectory as improving. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Akron, OH (62.2% good, AQI 45); Carson City, NV (79.3% good, AQI 45); Clinton, IA (59.9% good, AQI 45).

Air Quality Summary

Median AQI

45

Good

Good Days

65.6%

139 of 212 days

Max AQI

101

USG

Health Grade

Moderate

90th pct: 66

AQI Day Breakdown (2025)

Distribution of 212 monitored days across EPA AQI categories.

Good

139

66%

Moderate

72

34%

USG

1

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The York-Hanover, PA metro area's air quality is rated Moderate based on 65.6% good air days. No unhealthy air days were recorded in 2025.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the York-Hanover, PA metro compare?

How York-Hanover, PA compares

Good-day share worse than US avg
York-Hanover, PA 65.6%
Akron, OH 62.2%
US average 71.3%
Median AQI worse than US avg
York-Hanover, PA 45
Akron, OH 45
US average 41
Unhealthy days / yr better than US avg
York-Hanover, PA 0
Akron, OH 0
US average 1

5-Year Air Quality Trend

Air quality is improving in the York-Hanover, PA metro. Best year: 2024 (240 good days).

Year Good Moderate Unhealthy Median AQI
2020 221 145 0 46
2021 168 187 0 51
2022 205 159 0 47
2023 198 150 3 48
2024 240 125 0 44
2025 139 72 0 45

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to York-Hanover, PA.

More Air Quality Data

Explore EPA air quality rankings and guides across U.S. metros and counties.

Air Quality Guides

Frequently Asked Questions

What is the air quality in the York-Hanover, PA metro area?
The York-Hanover, PA metro area has a median Air Quality Index (AQI) of 45, rated "Good." 65.6% of monitored days (139 out of 212) had good air quality in 2025.
How many unhealthy air days does York-Hanover, PA have?
In 2025, the York-Hanover, PA metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 101.
Is air quality in York-Hanover, PA getting better or worse?
Air quality in the York-Hanover, PA metro is improving based on 5-year trends (2020-2025). Best year: 2024 with 240 good days. Worst year: 2025 with 139 good days.
What does AQI 45 mean for health?
An AQI of 45 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for York-Hanover, PA?
The 90th percentile AQI for the York-Hanover, PA metro area is 66, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 101 (USG).
How does York-Hanover, PA compare to other metro areas?
The York-Hanover, PA metro has 65.6% good air days. Similar metros: Akron, OH (62.2% good), Carson City, NV (79.3% good), Clinton, IA (59.9% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2025. See our methodology for how AQI, median, and coverage figures are computed.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary files (metro-level) · 2020–2025

Every figure on PlainAir 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.