Metro area air quality · 2025

Lancaster, PA

Median AQI 46 (Good). 60.0% of monitored days rated Good across this metro's EPA monitoring network.

46
Median AQI
60.0%
Good-air days
0
Unhealthy days
24%
Cleaner than US metros

Aggregated from EPA Air Quality System (2025), 210 monitored days. EPA AQS →

The verdict

The Lancaster, PA metro runs good on the EPA scale, among the more polluted US metros, a median AQI of 46 with 60.0% of 210 monitored days in the Good band.

46
median AQI · Good
60.0%
days rated Good
24%
cleaner than US metros
119
worst single reading

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

Insights: Lancaster, PA metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 46 over 210 measured days in 2025, which corresponds to a Good band and a Moderate metro-wide health grade. The monitored-day split lands at 126 Good days (60%), 82 Moderate (39%), and 2 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 72 while the highest single-day reading hit 119 (USG). Metro residents averaged roughly 18.0 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, good days shifted by -51 and the median AQI moved -5 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 Albany, GA (55.6% good, AQI 46); Asheville, NC (68.1% good, AQI 46); Cedar City, UT (70.0% good, AQI 46).

Air Quality Summary

Median AQI

46

Good

Good Days

60.0%

126 of 210 days

Max AQI

119

USG

Health Grade

Moderate

90th pct: 72

AQI Day Breakdown (2025)

Distribution of 210 monitored days across EPA AQI categories.

Good

126

60%

Moderate

82

39%

USG

2

1%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Lancaster, PA metro area's air quality is rated Moderate based on 60.0% 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 Lancaster, PA metro compare?

How Lancaster, PA compares

Good-day share worse than US avg
Lancaster, PA 60.0%
Albany, GA 55.6%
US average 71.3%
Median AQI worse than US avg
Lancaster, PA 46
Albany, GA 46
US average 41
Unhealthy days / yr better than US avg
Lancaster, PA 0
Albany, GA 0
US average 1

5-Year Air Quality Trend

Air quality is improving in the Lancaster, PA metro. Best year: 2024 (189 good days).

Year Good Moderate Unhealthy Median AQI
2020 177 184 1 51
2021 100 257 1 56
2022 84 274 1 59
2023 108 243 3 58
2024 189 174 0 50
2025 126 82 0 46

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Lancaster, 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 Lancaster, PA metro area?
The Lancaster, PA metro area has a median Air Quality Index (AQI) of 46, rated "Good." 60.0% of monitored days (126 out of 210) had good air quality in 2025.
How many unhealthy air days does Lancaster, PA have?
In 2025, the Lancaster, PA metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 119.
Is air quality in Lancaster, PA getting better or worse?
Air quality in the Lancaster, PA metro is improving based on 5-year trends (2020-2025). Best year: 2024 with 189 good days. Worst year: 2022 with 84 good days.
What does AQI 46 mean for health?
An AQI of 46 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 Lancaster, PA?
The 90th percentile AQI for the Lancaster, PA metro area is 72, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 119 (USG).
How does Lancaster, PA compare to other metro areas?
The Lancaster, PA metro has 60.0% good air days. Similar metros: Albany, GA (55.6% good), Asheville, NC (68.1% good), Cedar City, UT (70.0% 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.