Median AQI
42
Good
New York · County air quality · 2025
Essex County, New York
Median AQI 42 (Good). 79.8% of monitored days rated Good, direct from EPA Air Quality System stations.
- 42
- Median AQI
- 79.8%
- Good-air days
- 1
- Unhealthy days
- 52%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Essex County's air is good on balance, cleaner than the median US county, a median AQI of 42 with 79.8% of 273 monitored days in the Good band, driven mainly by Ozone.
- 42
- median AQI · Good
- 79.8%
- days rated Good
- Ozone
- main pollutant
- 52%
- cleaner than US counties
1 day reached Unhealthy or worse; the worst single reading hit AQI 159.
Data updated July 2026
- Good · 218 d · 79.9%
- Moderate · 50 d · 18.3%
- USG · 4 d · 1.5%
- Unhealthy · 1 d · 0.4%
How did Essex County's air break down in 2025?
Across 273 monitored days, 218 fell in the Good band (AQI 0–50) and 1 reached Unhealthy or worse. The worst single day peaked at AQI 159 (Unhealthy).
EPA AQS →Air quality data from EPA Air Quality System (2025). 273 days monitored. Median AQI: 42 (Good).
Insights: Essex County, New York. EPA monitors recorded a median Air Quality Index of 42 across 273 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 218 (80%) fell in the Good band (AQI 0–50), 50 (18%) registered Moderate readings, and 4 (1%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 64, while the worst single-day peak hit 159 (Unhealthy). Residents averaged about 24.0 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (236 days), PM2.5 (37 days). Across the 2020–2025 trend window, good days shifted by -126 and the median AQI moved +3 points, placing the multi-year trajectory at worsening. Residents and visitors experienced 1 unhealthy-or-worse days combined, periods when the EPA recommends sensitive groups limit prolonged outdoor exertion. Nearby counties show comparable readings: Albany (67.4% good, AQI 39); Bronx (56.6% good, AQI 47); Chautauqua (88.6% good, AQI 39); Dutchess (92.7% good, AQI 37); Erie (61.3% good, AQI 44); Hamilton (96.6% good, AQI 36).
Air Quality Summary
Good Days
79.8%
218 of 273 monitored days
4.8pp vs 75% target
Max AQI Recorded
159
Unhealthy
Health Grade
Good
90th-pct AQI 64
Essex County, Good days share 79.8%
National avg
Share of monitored days at AQI 0-50 (Good band).
Essex County, Unhealthy-or-worse share 0.4%
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 273 monitored days across EPA AQI categories.
Good
218
80%
Moderate
50
18%
USG
4
1%
Unhealthy
1
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Essex County.
- Ozone · 236 days · 86.4%
- PM2.5 · 37 days · 13.6%
Health Impact Assessment
Good
Essex County's air quality is rated Good based on 79.8% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.
Air quality is acceptable most days, but 4 days reached "Unhealthy for Sensitive Groups" (AQI 101-150) and peak AQI reached 159. Sensitive groups should monitor real-time conditions at AirNow.gov.
The dominant pollutant is Ozone, driving AQI on 236 of 273 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Essex County. Best year: 2020 (344 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 344 | 21 | 0 | 0 | 39 | 80 |
| 2021 | 310 | 54 | 1 | 0 | 40 | 101 |
| 2022 | 342 | 21 | 2 | 0 | 41 | 115 |
| 2023 | 296 | 59 | 8 | 2 | 42 | 161 |
| 2024 | 310 | 56 | 0 | 0 | 41 | 80 |
| 2025 | 218 | 50 | 4 | 1 | 42 | 159 |
How does Essex County compare?
How Essex County compares
Good-day share better than US avg
Essex County 79.8%
Albany County, New York 67.4%
US average 76.5%
Median AQI worse than US avg
Essex County 42
Albany County, New York 39
US average 38
Unhealthy days / yr worse than US avg
Essex County 1
Albany County, New York 0
US average 0
Other Counties in New York
Air quality comparison for nearby counties in New York.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Essex County.
Adams County, Pennsylvania
AQI 42 · 73.8% good
Anderson County, Tennessee
AQI 42 · 91.0% good
Andrew County, Missouri
AQI 42 · 84.3% good
Armstrong County, Pennsylvania
AQI 42 · 68.1% good
Baldwin County, Alabama
AQI 42 · 72.2% good
Belmont County, Ohio
AQI 42 · 63.0% good
What Essex County's air means for you
On most days the air here is fine, but Ozone drives 1 unhealthy-or-worse day a year that sensitive groups should plan around.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-Ozone days, the guide explains what a median of 42 means for exposure. Health guidance
- See how Essex County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Essex County with its New York neighbours before drawing a conclusion about the region. All of New York
Based on 273 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 Essex County, New York? ▼
Essex County has a median Air Quality Index (AQI) of 42, rated "Good." 79.8% of monitored days (218 out of 273) had good air quality in 2025.
What is the main pollutant in Essex County? ▼
The primary pollutant in Essex County is Ozone (O3), which was the main AQI driver on 236 days (86% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Essex County have? ▼
In 2025, Essex County recorded 1 unhealthy air days (1 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 159.
Is the air quality in Essex County getting better or worse? ▼
Air quality in Essex County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 344 good days. Worst year: 2025 with 218 good days.
What does AQI 42 mean for health? ▼
Essex County's median AQI of 42 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 Essex County compare to other counties in New York? ▼
Essex County has 79.8% good air days. Nearby counties in New York: Albany (67.4% good), Bronx (56.6% good), Chautauqua (88.6% good), Dutchess (92.7% good), Erie (61.3% good), Hamilton (96.6% good).
What is the 90th percentile AQI in Essex County? ▼
The 90th percentile AQI for Essex County is 64, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 159 (Unhealthy).
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.