New Jersey · County air quality · 2025

Passaic County, New Jersey

Median AQI 41 (Good). 76.2% of monitored days rated Good, direct from EPA Air Quality System stations.

41
Median AQI
76.2%
Good-air days
0
Unhealthy days
42%
Cleaner than US counties

The verdict

According to EPA Air Quality System monitoring data, Passaic County's air is good on balance, more polluted than the median US county, a median AQI of 41 with 76.2% of 181 monitored days in the Good band, driven mainly by Ozone.

41
median AQI · Good
76.2%
days rated Good
Ozone
main pollutant
42%
cleaner than US counties

Not one day crossed into the Unhealthy tier; the worst single reading was AQI 108.

Data updated July 2026

Passaic 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 181 monitored days G M Median AQI 41 0 50 100 150 200 300 500 Passaic County
  • Good · 138 d · 76.2%
  • Moderate · 41 d · 22.7%
  • USG · 2 d · 1.1%

How did Passaic County's air break down in 2025?

Across 181 monitored days, 138 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 108 (USG).

EPA AQS →

Air quality data from EPA Air Quality System (2025). 181 days monitored. Median AQI: 41 (Good).

Insights: Passaic County, New Jersey. EPA monitors recorded a median Air Quality Index of 41 across 181 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 138 (76%) fell in the Good band (AQI 0–50), 41 (23%) registered Moderate readings, and 2 (1%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 58, while the worst single-day peak hit 108 (USG). Residents averaged about 22.9 clean-air days per 30-day window during the monitoring year.

The full pollutant mix ranks as Ozone (98 days), PM2.5 (83 days). Across the 2020–2025 trend window, good days shifted by -107 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 108, usg but never Unhealthy. Nearby counties show comparable readings: Atlantic (79.6% good, AQI 38); Bergen (71.1% good, AQI 40); Camden (69.4% good, AQI 44); Cumberland (73.0% good, AQI 42); Gloucester (72.4% good, AQI 43); Hudson (74.7% good, AQI 41).

Air Quality Summary

Median AQI

41

Good

Good Days

76.2%

138 of 181 monitored days

1.2pp vs 75% target

Max AQI Recorded

108

USG

Health Grade

Good

90th-pct AQI 58

Passaic County, Good days share 76.2%
National avg

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

Passaic 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 181 monitored days across EPA AQI categories.

Good

138

76%

Moderate

41

23%

USG

2

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 Passaic County.

Passaic County, New Jersey 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 · 54.1% PM2.5 · 45.9% 0% 25% 50% 75% 100% Passaic County, New Jersey · 181 monitored days Criteria pollutant column
  • Ozone · 98 days · 54.1%
  • PM2.5 · 83 days · 45.9%
Ozone (O3) 98 days (54%)

How Ozone affects health →

Fine Particles (PM2.5) 83 days (46%)

How PM2.5 affects health →

Health Impact Assessment

Good

Passaic County's air quality is rated Good based on 76.2% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 76.2% 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 98 of 181 monitored days.

5-Year Air Quality Trend

Air quality is worsening in Passaic County. Best year: 2024 (269 good days).

Year Good Moderate USG Unhealthy Median AQI
2020 245 17 0 0 37
2021 243 18 0 0 37
2022 251 53 0 0 38
2023 241 104 4 4 42
2024 269 95 2 0 38
2025 138 41 2 0 41

How does Passaic County compare?

How Passaic County compares

Good-day share about average
Passaic County 76.2%
Atlantic County, New Jersey 79.6%
US average 76.5%
Median AQI worse than US avg
Passaic County 41
Atlantic County, New Jersey 38
US average 38
Unhealthy days / yr about average
Passaic County 0
Atlantic County, New Jersey 0
US average 0

Other Counties in New Jersey

Air quality comparison for nearby counties in New Jersey.

Counties with Similar Air Quality

Counties across the US with a similar median AQI to Passaic County.

What Passaic 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 Passaic County ranks against every monitored U.S. county on Good-day share. County rankings
  • Compare Passaic County with its New Jersey neighbours before drawing a conclusion about the region. All of New Jersey

Based on 181 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 Passaic County, New Jersey?
Passaic County has a median Air Quality Index (AQI) of 41, rated "Good." 76.2% of monitored days (138 out of 181) had good air quality in 2025.
What is the main pollutant in Passaic County?
The primary pollutant in Passaic County is Ozone (O3), which was the main AQI driver on 98 days (54% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Passaic County have?
In 2025, Passaic County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 108.
Is the air quality in Passaic County getting better or worse?
Air quality in Passaic County is worsening based on 5-year trends (2020-2025). Best year: 2024 with 269 good days. Worst year: 2025 with 138 good days.
What does AQI 41 mean for health?
Passaic 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 Passaic County compare to other counties in New Jersey?
Passaic County has 76.2% good air days. Nearby counties in New Jersey: Atlantic (79.6% good), Bergen (71.1% good), Camden (69.4% good), Cumberland (73.0% good), Gloucester (72.4% good), Hudson (74.7% good).
What is the 90th percentile AQI in Passaic County?
The 90th percentile AQI for Passaic County is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 108 (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.