Median AQI
38
Good
Virginia · County air quality · 2025
Stafford County, Virginia
Median AQI 38 (Good). 95.2% of monitored days rated Good, direct from EPA Air Quality System stations.
- 38
- Median AQI
- 95.2%
- Good-air days
- 0
- Unhealthy days
- 90%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Stafford County's air is good on balance, among the cleanest 10% of US counties, a median AQI of 38 with 95.2% of 268 monitored days in the Good band, driven mainly by Ozone.
- 38
- median AQI · Good
- 95.2%
- days rated Good
- Ozone
- main pollutant
- 90%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 77.
Data updated July 2026
- Good · 255 d · 95.1%
- Moderate · 13 d · 4.9%
How did Stafford County's air break down in 2025?
Across 268 monitored days, 255 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 77 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 268 days monitored. Median AQI: 38 (Good).
Insights: Stafford County, Virginia. EPA monitors recorded a median Air Quality Index of 38 across 268 measured days in 2025, earning a Good classification and a Excellent health grade. Of those days, 255 (95%) fell in the Good band (AQI 0–50), 13 (5%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 48, while the worst single-day peak hit 77 (Moderate). Residents averaged about 28.5 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (267 days), PM10 (1 days). Across the 2020–2025 trend window, good days shifted by -102 and the median AQI moved +6 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 77, moderate but never Unhealthy. Nearby counties show comparable readings: Albemarle (77.9% good, AQI 41); Arlington (84.8% good, AQI 40); Bristol City (78.3% good, AQI 33); Caroline (96.2% good, AQI 37); Carroll (100.0% good, AQI 9); Charles (88.6% good, AQI 38).
Air Quality Summary
Good Days
95.2%
255 of 268 monitored days
20.2pp vs 75% target
Max AQI Recorded
77
Moderate
Health Grade
Excellent
90th-pct AQI 48
Stafford County, Good days share 95.2%
National avg
Share of monitored days at AQI 0-50 (Good band).
Stafford 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 268 monitored days across EPA AQI categories.
Good
255
95%
Moderate
13
5%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Stafford County.
- Ozone · 267 days · 99.6%
- PM10 · 1 days · 0.4%
Health Impact Assessment
Excellent
Stafford County's air quality is rated Excellent based on 95.2% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 95.2% of monitored days in 2025, with a median AQI of 38. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 267 of 268 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Stafford County. Best year: 2020 (357 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 357 | 5 | 0 | 0 | 32 | 84 |
| 2021 | 337 | 20 | 1 | 0 | 35 | 115 |
| 2022 | 351 | 11 | 0 | 0 | 35 | 74 |
| 2023 | 332 | 31 | 1 | 1 | 37 | 169 |
| 2024 | 353 | 9 | 0 | 0 | 35 | 90 |
| 2025 | 255 | 13 | 0 | 0 | 38 | 77 |
How does Stafford County compare?
How Stafford County compares
Good-day share better than US avg
Stafford County 95.2%
Albemarle County, Virginia 77.9%
US average 76.5%
Median AQI about average
Stafford County 38
Albemarle County, Virginia 41
US average 38
Unhealthy days / yr about average
Stafford County 0
Albemarle County, Virginia 0
US average 0
Other Counties in Virginia
Air quality comparison for nearby counties in Virginia.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Stafford County.
Adams County, Illinois
AQI 38 · 94.4% good
Anoka County, Minnesota
AQI 38 · 82.1% good
Atlantic County, New Jersey
AQI 38 · 79.6% good
Avery County, North Carolina
AQI 38 · 93.9% good
Barnstable County, Massachusetts
AQI 38 · 92.5% good
Bay County, Michigan
AQI 38 · 71.8% good
What Stafford 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 38 means for exposure. Health guidance
- See how Stafford County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Stafford County with its Virginia neighbours before drawing a conclusion about the region. All of Virginia
Based on 268 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 Stafford County, Virginia? ▼
Stafford County has a median Air Quality Index (AQI) of 38, rated "Good." 95.2% of monitored days (255 out of 268) had good air quality in 2025.
What is the main pollutant in Stafford County? ▼
The primary pollutant in Stafford County is Ozone (O3), which was the main AQI driver on 267 days (100% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Stafford County have? ▼
In 2025, Stafford County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 77.
Is the air quality in Stafford County getting better or worse? ▼
Air quality in Stafford County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 357 good days. Worst year: 2025 with 255 good days.
What does AQI 38 mean for health? ▼
Stafford County's median AQI of 38 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 Stafford County compare to other counties in Virginia? ▼
Stafford County has 95.2% good air days. Nearby counties in Virginia: Albemarle (77.9% good), Arlington (84.8% good), Bristol City (78.3% good), Caroline (96.2% good), Carroll (100.0% good), Charles (88.6% good).
What is the 90th percentile AQI in Stafford County? ▼
The 90th percentile AQI for Stafford County is 48, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 77 (Moderate).
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.