Maryland · County air quality · 2025

Prince George's County, Maryland

Median AQI 41 (Good). 83.5% of monitored days rated Good, direct from EPA Air Quality System stations.

41
Median AQI
83.5%
Good-air days
0
Unhealthy days
62%
Cleaner than US counties

The verdict

According to EPA Air Quality System monitoring data, Prince George's County's air is good on balance, cleaner than the median US county, a median AQI of 41 with 83.5% of 304 monitored days in the Good band, driven mainly by Ozone.

41
median AQI · Good
83.5%
days rated Good
Ozone
main pollutant
62%
cleaner than US counties

Not one day crossed into the Unhealthy tier; the worst single reading was AQI 126.

Data updated July 2026

Prince George's 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 304 monitored days G M Median AQI 41 0 50 100 150 200 300 500 Prince George's County
  • Good · 254 d · 83.6%
  • Moderate · 47 d · 15.5%
  • USG · 3 d · 1.0%

How did Prince George's County's air break down in 2025?

Across 304 monitored days, 254 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 126 (USG).

EPA AQS →

Air quality data from EPA Air Quality System (2025). 304 days monitored. Median AQI: 41 (Good).

Insights: Prince George's County, Maryland. EPA monitors recorded a median Air Quality Index of 41 across 304 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 254 (84%) fell in the Good band (AQI 0–50), 47 (15%) registered Moderate readings, and 3 (1%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 61, while the worst single-day peak hit 126 (USG). Residents averaged about 25.1 clean-air days per 30-day window during the monitoring year.

The full pollutant mix ranks as Ozone (254 days), PM2.5 (50 days). Across the 2020–2025 trend window, good days shifted by -60 and the median AQI moved +2 points, placing the multi-year trajectory at stable. The worst single reading over the 2020–2025 window was AQI 126, usg but never Unhealthy. Nearby counties show comparable readings: Anne Arundel (87.2% good, AQI 40); Baltimore (70.4% good, AQI 44); Baltimore (City) (68.7% good, AQI 44); Calvert (94.6% good, AQI 38); Carroll (90.3% good, AQI 38); Cecil (80.9% good, AQI 41).

Air Quality Summary

Median AQI

41

Good

Good Days

83.5%

254 of 304 monitored days

8.5pp vs 75% target

Max AQI Recorded

126

USG

Health Grade

Good

90th-pct AQI 61

Prince George's County, Good days share 83.5%
National avg

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

Prince George's 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).

AQI Day Breakdown (2025)

Distribution of 304 monitored days across EPA AQI categories.

Good

254

84%

Moderate

47

15%

USG

3

1%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Pollutant Breakdown

Days where each pollutant was the primary driver of AQI readings in Prince George's County.

Prince George's County, Maryland 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 · 83.6% PM2.5 · 16.4% 0% 25% 50% 75% 100% Prince George's County, Maryland · 304 monitored days Criteria pollutant column
  • Ozone · 254 days · 83.6%
  • PM2.5 · 50 days · 16.4%
Ozone (O3) 254 days (84%)

How Ozone affects health →

Fine Particles (PM2.5) 50 days (16%)

How PM2.5 affects health →

Health Impact Assessment

Good

Prince George's County's air quality is rated Good based on 83.5% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 83.5% of monitored days in 2025, with a median AQI of 41. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is Ozone, driving AQI on 254 of 304 monitored days.

5-Year Air Quality Trend

Air quality is stable in Prince George's County. Best year: 2020 (314 good days).

Year Good Moderate USG Unhealthy Median AQI
2020 314 51 1 0 39
2021 287 73 5 0 41
2022 313 51 1 0 39
2023 253 101 8 3 44
2024 280 83 3 0 39
2025 254 47 3 0 41

How does Prince George's County compare?

How Prince George's County compares

Good-day share better than US avg
Prince George's County 83.5%
Anne Arundel County, Maryland 87.2%
US average 76.5%
Median AQI worse than US avg
Prince George's County 41
Anne Arundel County, Maryland 40
US average 38
Unhealthy days / yr about average
Prince George's County 0
Anne Arundel County, Maryland 0
US average 0

Other Counties in Maryland

Air quality comparison for nearby counties in Maryland.

Counties with Similar Air Quality

Counties across the US with a similar median AQI to Prince George's County.

What Prince George's County's air means for you

The air here stays in the breathable range year-round, with Ozone the main thing to watch.

  • Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-Ozone days, the guide explains what a median of 41 means for exposure. Health guidance
  • See how Prince George's County ranks against every monitored U.S. county on Good-day share. County rankings
  • Compare Prince George's County with its Maryland neighbours before drawing a conclusion about the region. All of Maryland

Based on 304 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.

More Air Quality Data

Air Quality Guides

Frequently Asked Questions

What is the air quality in Prince George's County, Maryland?
Prince George's County has a median Air Quality Index (AQI) of 41, rated "Good." 83.5% of monitored days (254 out of 304) had good air quality in 2025.
What is the main pollutant in Prince George's County?
The primary pollutant in Prince George's County is Ozone (O3), which was the main AQI driver on 254 days (84% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Prince George's County have?
In 2025, Prince George's County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 126.
Is the air quality in Prince George's County getting better or worse?
Air quality in Prince George's County is stable based on 5-year trends (2020-2025). Best year: 2020 with 314 good days. Worst year: 2023 with 253 good days.
What does AQI 41 mean for health?
Prince George's County's median AQI of 41 falls in the "Good" category. See the <a href="/guides/understanding-aqi" class="underline">AQI category guide</a> for what each range means for health.
How does Prince George's County compare to other counties in Maryland?
Prince George's County has 83.5% good air days. Nearby counties in Maryland: Anne Arundel (87.2% good), Baltimore (70.4% good), Baltimore (City) (68.7% good), Calvert (94.6% good), Carroll (90.3% good), Cecil (80.9% good).
What is the 90th percentile AQI in Prince George's County?
The 90th percentile AQI for Prince George's County is 61, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 126 (USG).

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.

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.