North Carolina · County air quality · 2025

Carteret County, North Carolina

Median AQI 37 (Good). 94.2% of monitored days rated Good, direct from EPA Air Quality System stations.

37
Median AQI
94.2%
Good-air days
0
Unhealthy days
86%
Cleaner than US counties

The verdict

According to EPA Air Quality System monitoring data, Carteret County's air is good on balance, cleaner than most US counties, a median AQI of 37 with 94.2% of 224 monitored days in the Good band, driven mainly by Ozone.

37
median AQI · Good
94.2%
days rated Good
Ozone
main pollutant
86%
cleaner than US counties

Not one day crossed into the Unhealthy tier; the worst single reading was AQI 80.

Data updated July 2026

Carteret 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 224 monitored days G Median AQI 37 0 50 100 150 200 300 500 Carteret County
  • Good · 211 d · 94.2%
  • Moderate · 13 d · 5.8%

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

Across 224 monitored days, 211 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 80 (Moderate).

EPA AQS →

Air quality data from EPA Air Quality System (2025). 224 days monitored. Median AQI: 37 (Good).

Insights: Carteret County, North Carolina. EPA monitors recorded a median Air Quality Index of 37 across 224 measured days in 2025, earning a Good classification and a Excellent health grade. Of those days, 211 (94%) fell in the Good band (AQI 0–50), 13 (6%) 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 80 (Moderate). Residents averaged about 28.3 clean-air days per 30-day window during the monitoring year.

The full pollutant mix ranks as Ozone (224 days). Across the 2020–2025 trend window, good days shifted by -148 and the median AQI moved +3 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 80, moderate but never Unhealthy. Nearby counties show comparable readings: Alexander (92.4% good, AQI 39); Avery (93.9% good, AQI 38); Buncombe (71.4% good, AQI 42); Caldwell (96.2% good, AQI 37); Caswell (94.6% good, AQI 39); Catawba (67.2% good, AQI 43).

Air Quality Summary

Median AQI

37

Good

Good Days

94.2%

211 of 224 monitored days

19.2pp vs 75% target

Max AQI Recorded

80

Moderate

Health Grade

Excellent

90th-pct AQI 48

Carteret County, Good days share 94.2%
National avg

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

Carteret 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 224 monitored days across EPA AQI categories.

Good

211

94%

Moderate

13

6%

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 Carteret County.

Carteret County, North Carolina 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 · 100.0% 0% 25% 50% 75% 100% Carteret County, North Carolina · 224 monitored days Criteria pollutant column
  • Ozone · 224 days · 100.0%
Ozone (O3) 224 days (100%)

How Ozone affects health →

Health Impact Assessment

Excellent

Carteret County's air quality is rated Excellent based on 94.2% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 94.2% of monitored days in 2025, with a median AQI of 37. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is Ozone, driving AQI on 224 of 224 monitored days.

5-Year Air Quality Trend

Air quality is worsening in Carteret County. Best year: 2020 (359 good days).

Year Good Moderate USG Unhealthy Median AQI
2020 359 3 0 0 34
2021 337 15 0 0 35
2022 346 13 0 0 35
2023 319 31 2 0 38
2024 357 7 0 0 35
2025 211 13 0 0 37

How does Carteret County compare?

How Carteret County compares

Good-day share better than US avg
Carteret County 94.2%
Alexander County, North Carolina 92.4%
US average 76.5%
Median AQI better than US avg
Carteret County 37
Alexander County, North Carolina 39
US average 38
Unhealthy days / yr about average
Carteret County 0
Alexander County, North Carolina 0
US average 0

Other Counties in North Carolina

Air quality comparison for nearby counties in North Carolina.

Counties with Similar Air Quality

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

What Carteret 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 37 means for exposure. Health guidance
  • See how Carteret County ranks against every monitored U.S. county on Good-day share. County rankings
  • Compare Carteret County with its North Carolina neighbours before drawing a conclusion about the region. All of North Carolina

Based on 224 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 Carteret County, North Carolina?
Carteret County has a median Air Quality Index (AQI) of 37, rated "Good." 94.2% of monitored days (211 out of 224) had good air quality in 2025.
What is the main pollutant in Carteret County?
The primary pollutant in Carteret County is Ozone (O3), which was the main AQI driver on 224 days (100% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Carteret County have?
In 2025, Carteret County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 80.
Is the air quality in Carteret County getting better or worse?
Air quality in Carteret County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 359 good days. Worst year: 2025 with 211 good days.
What does AQI 37 mean for health?
Carteret County's median AQI of 37 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 Carteret County compare to other counties in North Carolina?
Carteret County has 94.2% good air days. Nearby counties in North Carolina: Alexander (92.4% good), Avery (93.9% good), Buncombe (71.4% good), Caldwell (96.2% good), Caswell (94.6% good), Catawba (67.2% good).
What is the 90th percentile AQI in Carteret County?
The 90th percentile AQI for Carteret County is 48, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 80 (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.