Median AQI
47
Good
Georgia · County air quality · 2025
Washington County, Georgia
Median AQI 47 (Good). 57.9% of monitored days rated Good, direct from EPA Air Quality System stations.
- 47
- Median AQI
- 57.9%
- Good-air days
- 0
- Unhealthy days
- 11%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Washington County's air is good on balance, among the more polluted 10% of US counties, a median AQI of 47 with 57.9% of 242 monitored days in the Good band, driven mainly by PM2.5.
- 47
- median AQI · Good
- 57.9%
- days rated Good
- PM2.5
- main pollutant
- 11%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 82.
Data updated July 2026
- Good · 140 d · 57.9%
- Moderate · 102 d · 42.1%
How did Washington County's air break down in 2025?
Across 242 monitored days, 140 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 82 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 242 days monitored. Median AQI: 47 (Good).
Insights: Washington County, Georgia. EPA monitors recorded a median Air Quality Index of 47 across 242 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 140 (58%) fell in the Good band (AQI 0–50), 102 (42%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 60, while the worst single-day peak hit 82 (Moderate). Residents averaged about 17.4 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (242 days). Across the 2020–2025 trend window, good days shifted by -90 and the median AQI moved +4 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 82, moderate but never Unhealthy. Nearby counties show comparable readings: Bibb (49.5% good, AQI 51); Charlton (79.0% good, AQI 24); Chatham (66.7% good, AQI 44); Clarke (66.7% good, AQI 44); Clayton (53.1% good, AQI 49); Cobb (92.5% good, AQI 36).
Air Quality Summary
Good Days
57.9%
140 of 242 monitored days
-17.1pp vs 75% target
Max AQI Recorded
82
Moderate
Health Grade
Moderate
90th-pct AQI 60
Washington County, Good days share 57.9%
National avg
Share of monitored days at AQI 0-50 (Good band).
Washington 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 242 monitored days across EPA AQI categories.
Good
140
58%
Moderate
102
42%
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 Washington County.
- PM2.5 · 242 days · 100.0%
Health Impact Assessment
Moderate
Washington County's air quality is rated Moderate based on 57.9% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 57.9% of monitored days in 2025, with a median AQI of 47. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is PM2.5, driving AQI on 242 of 242 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Washington County. Best year: 2020 (230 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 230 | 122 | 2 | 0 | 43 | 112 |
| 2021 | 178 | 184 | 3 | 0 | 51 | 111 |
| 2022 | 142 | 217 | 3 | 0 | 52 | 112 |
| 2023 | 160 | 197 | 2 | 1 | 52 | 161 |
| 2024 | 221 | 139 | 1 | 0 | 44 | 101 |
| 2025 | 140 | 102 | 0 | 0 | 47 | 82 |
How does Washington County compare?
How Washington County compares
Good-day share worse than US avg
Washington County 57.9%
Bibb County, Georgia 49.5%
US average 76.5%
Median AQI worse than US avg
Washington County 47
Bibb County, Georgia 51
US average 38
Unhealthy days / yr about average
Washington County 0
Bibb County, Georgia 0
US average 0
Other Counties in Georgia
Air quality comparison for nearby counties in Georgia.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Washington County.
Beaver County, Pennsylvania
AQI 47 · 54.3% good
Bell County, Texas
AQI 47 · 61.3% good
Bowie County, Texas
AQI 47 · 57.3% good
Bronx County, New York
AQI 47 · 56.6% good
Butte County, California
AQI 47 · 66.1% good
Calcasieu County, Louisiana
AQI 47 · 61.5% good
What Washington County's air means for you
The air here stays in the breathable range year-round, with PM2.5 the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 47 means for exposure. Health guidance
- See how Washington County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Washington County with its Georgia neighbours before drawing a conclusion about the region. All of Georgia
Based on 242 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 Washington County, Georgia? ▼
Washington County has a median Air Quality Index (AQI) of 47, rated "Good." 57.9% of monitored days (140 out of 242) had good air quality in 2025.
What is the main pollutant in Washington County? ▼
The primary pollutant in Washington County is Fine Particles (PM2.5), which was the main AQI driver on 242 days (100% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Washington County have? ▼
In 2025, Washington County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 82.
Is the air quality in Washington County getting better or worse? ▼
Air quality in Washington County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 230 good days. Worst year: 2025 with 140 good days.
What does AQI 47 mean for health? ▼
Washington County's median AQI of 47 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 Washington County compare to other counties in Georgia? ▼
Washington County has 57.9% good air days. Nearby counties in Georgia: Bibb (49.5% good), Charlton (79.0% good), Chatham (66.7% good), Clarke (66.7% good), Clayton (53.1% good), Cobb (92.5% good).
What is the 90th percentile AQI in Washington County? ▼
The 90th percentile AQI for Washington County is 60, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 82 (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.