Metro area air quality · 2025

Hagerstown-Martinsburg, MD-WV

Median AQI 41 (Good). 77.3% of monitored days rated Good across this metro's EPA monitoring network.

41
Median AQI
77.3%
Good-air days
0
Unhealthy days
62%
Cleaner than US metros

Hagerstown-Martinsburg, MD-WV posted a 2025 median AQI of 41 (Good) with 77.3% Good days

According to the U.S. EPA Air Quality System, the Hagerstown-Martinsburg, MD-WV CBSA recorded a median AQI of 41 across 362 monitored days in 2025, with 77.3% rated Good and 0 unhealthy or worse. This is an annual metro comparison, not a live advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US metros
The Hagerstown-Martinsburg, MD-WV CBSA's 77.3% Good-day share places it cleaner than 62% of US metros in 2025.
Closest median-AQI peer
Adrian, MI (69.3% Good, median AQI 41) is the closest nationwide median-AQI peer to Hagerstown-Martinsburg, MD-WV.
2020–2025 Good-day shift
Hagerstown-Martinsburg, MD-WV's Good-day share moved +1.1 points from 2020 to 2025 (median AQI +0).
Median AQI
Median AQI: 41

Aggregated from EPA Air Quality System (2025), 362 monitored days. EPA AQS →

The verdict

Hagerstown-Martinsburg, MD-WV's peak reading 90 stays in the lower max-AQI tercile on this extract. On the EPA scale the metro runs good, cleaner than the median US metro, with a median AQI of 41 and 77.3% of 362 monitored days in the Good band.

41
median AQI · Good
77.3%
days rated Good
62%
cleaner than US metros
90
worst single reading

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

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Hagerstown-Martinsburg, MD-WV metro's Good-day share rose from 74.4% to 77.3% between the 2024 and 2025 EPA annual releases, a change of +3.0 percentage points.

Compared against 363 monitored days in 2024 and 362 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

Hagerstown-Martinsburg, MD-WV's peak reading 90 stays in the lower max-AQI tercile on this extract. Signature read: peak AQI 90 (low tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 41 over 362 measured days in 2025 (Good / Good). The monitored-day split lands at 280 Good (77%), 82 Moderate (23%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 59; the highest single-day reading hit 90 (Moderate).

Across 2020–2025, Good-day share shifted +1.1 points and median AQI moved +0 (stable). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Adrian, MI (69.3% good, AQI 41); Albany-Schenectady-Troy, NY (67.7% good, AQI 41); Ann Arbor, MI (69.3% good, AQI 41).

Understanding AQI →

Air Quality Summary

Median AQI

41

Good

Good Days

77.3%

280 of 362 days

Max AQI

90

Moderate

Health Grade

Good

90th pct: 59

AQI Day Breakdown (2025)

Distribution of 362 monitored days across EPA AQI categories.

Good

280

77%

Moderate

82

23%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Hagerstown-Martinsburg, MD-WV metro area's air quality is rated Good based on 77.3% 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 Hagerstown-Martinsburg, MD-WV metro compare?

How Hagerstown-Martinsburg, MD-WV compares

Good-day share better than typical
Hagerstown-Martinsburg, MD-WV 77.3%
Adrian, MI 69.3%
Typical US metro 70.6%
Median AQI about typical
Hagerstown-Martinsburg, MD-WV 41
Adrian, MI 41
Typical US metro 41
Unhealthy days / yr better than typical
Hagerstown-Martinsburg, MD-WV 0
Adrian, MI 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Hagerstown-Martinsburg, MD-WV metro. Highest Good-day share: 2025 (77.3%, 280 of 362 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 276 86 0 41
2021 236 124 0 44
2022 270 84 0 42
2023 241 108 2 44
2024 270 93 0 42
2025 280 82 0 41

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Hagerstown-Martinsburg, MD-WV (41).

Adrian, MI

Median AQI 41 · 69.3% Good-day share

41

Albany-Schenectady-Troy, NY

Median AQI 41 · 67.7% Good-day share

41

Ann Arbor, MI

Median AQI 41 · 69.3% Good-day share

41

Bowling Green, KY

Median AQI 41 · 75.6% Good-day share

41

Brunswick, GA

Median AQI 41 · 74.3% Good-day share

41

Decatur, AL

Median AQI 41 · 78.4% Good-day share

41

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Hagerstown-Martinsburg, MD-WV's 0 (independent of median AQI).

Aberdeen, SD

0 unhealthy-or-worse days · median AQI 27

27

Aberdeen, WA

0 unhealthy-or-worse days · median AQI 22

22

Akron, OH

0 unhealthy-or-worse days · median AQI 45

45

Albany, GA

0 unhealthy-or-worse days · median AQI 46

46

Albany, OR

0 unhealthy-or-worse days · median AQI 27

27

Alexandria, LA

0 unhealthy-or-worse days · median AQI 37

37

Frequently Asked Questions

What is the 90th percentile AQI for Hagerstown-Martinsburg, MD-WV? ▼
The 90th percentile AQI for the Hagerstown-Martinsburg, MD-WV metro area is 59, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 90 (Moderate).
How many unhealthy air days does Hagerstown-Martinsburg, MD-WV have? ▼
In 2025, the Hagerstown-Martinsburg, MD-WV metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 90.
What is the air quality in the Hagerstown-Martinsburg, MD-WV metro area? ▼
The Hagerstown-Martinsburg, MD-WV metro area has a median Air Quality Index (AQI) of 41, rated "Good." 77.3% of monitored days (280 out of 362) had good air quality in 2025.
Is air quality in Hagerstown-Martinsburg, MD-WV getting better or worse? ▼
Air quality in the Hagerstown-Martinsburg, MD-WV metro is stable across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2025 at 77.3% (280 of 362 days). Lowest qualifying Good-day share: 2021 at 65.6% (236 of 360 days).
What does AQI 41 mean for health? ▼
An AQI of 41 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
How does Hagerstown-Martinsburg, MD-WV compare to other metro areas? ▼
The Hagerstown-Martinsburg, MD-WV metro has 77.3% good air days. Similar metros: Adrian, MI (69.3% good), Albany-Schenectady-Troy, NY (67.7% good), Ann Arbor, MI (69.3% good).

Data Sources

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

Read our methodology , how this data is sourced, computed, and verified.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Hagerstown-Martinsburg, MD-WV · 2020–2025