Louisiana · County air quality · 2025

Iberville County, Louisiana

Median AQI 41 (Good). 78.4% of monitored days rated Good, direct from EPA Air Quality System stations.

41
Median AQI
78.4%
Good-air days
0
Unhealthy days
47%
Cleaner than US counties

The verdict

According to EPA Air Quality System monitoring data, Iberville County's air is good on balance, more polluted than the median US county, a median AQI of 41 with 78.4% of 273 monitored days in the Good band, driven mainly by Ozone.

41
median AQI · Good
78.4%
days rated Good
Ozone
main pollutant
47%
cleaner than US counties

Not one day crossed into the Unhealthy tier; the worst single reading was AQI 105.

Data updated July 2026

Iberville 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 273 monitored days G M Median AQI 41 0 50 100 150 200 300 500 Iberville County
  • Good · 214 d · 78.4%
  • Moderate · 58 d · 21.2%
  • USG · 1 d · 0.4%

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

Across 273 monitored days, 214 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 105 (USG).

EPA AQS →

Air quality data from EPA Air Quality System (2025). 273 days monitored. Median AQI: 41 (Good).

Insights: Iberville County, Louisiana. EPA monitors recorded a median Air Quality Index of 41 across 273 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 214 (78%) fell in the Good band (AQI 0–50), 58 (21%) registered Moderate readings, and 1 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 61, while the worst single-day peak hit 105 (USG). Residents averaged about 23.5 clean-air days per 30-day window during the monitoring year.

The full pollutant mix ranks as Ozone (242 days), PM2.5 (31 days). Across the 2020–2025 trend window, good days shifted by -92 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 105, usg but never Unhealthy. Nearby counties show comparable readings: Ascension (94.1% good, AQI 33); Bossier (86.5% good, AQI 40); Caddo (84.3% good, AQI 38); Calcasieu (61.5% good, AQI 47); East Baton Rouge (49.3% good, AQI 51); Jefferson (58.6% good, AQI 48).

Air Quality Summary

Median AQI

41

Good

Good Days

78.4%

214 of 273 monitored days

3.4pp vs 75% target

Max AQI Recorded

105

USG

Health Grade

Good

90th-pct AQI 61

Iberville County, Good days share 78.4%
National avg

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

Iberville 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 273 monitored days across EPA AQI categories.

Good

214

78%

Moderate

58

21%

USG

1

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 Iberville County.

Iberville County, Louisiana 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 · 88.6% PM2.5 · 11.4% 0% 25% 50% 75% 100% Iberville County, Louisiana · 273 monitored days Criteria pollutant column
  • Ozone · 242 days · 88.6%
  • PM2.5 · 31 days · 11.4%
Ozone (O3) 242 days (89%)

How Ozone affects health →

Fine Particles (PM2.5) 31 days (11%)

How PM2.5 affects health →

Health Impact Assessment

Good

Iberville County's air quality is rated Good based on 78.4% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 78.4% 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 242 of 273 monitored days.

5-Year Air Quality Trend

Air quality is worsening in Iberville County. Best year: 2020 (306 good days).

Year Good Moderate USG Unhealthy Median AQI
2020 306 57 3 0 38
2021 299 63 3 0 39
2022 267 91 6 1 42
2023 253 99 12 1 44
2024 270 86 8 1 41
2025 214 58 1 0 41

How does Iberville County compare?

How Iberville County compares

Good-day share better than US avg
Iberville County 78.4%
Ascension County, Louisiana 94.1%
US average 76.5%
Median AQI worse than US avg
Iberville County 41
Ascension County, Louisiana 33
US average 38
Unhealthy days / yr about average
Iberville County 0
Ascension County, Louisiana 0
US average 0

Other Counties in Louisiana

Air quality comparison for nearby counties in Louisiana.

Counties with Similar Air Quality

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

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

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 Iberville County, Louisiana?
Iberville County has a median Air Quality Index (AQI) of 41, rated "Good." 78.4% of monitored days (214 out of 273) had good air quality in 2025.
What is the main pollutant in Iberville County?
The primary pollutant in Iberville County is Ozone (O3), which was the main AQI driver on 242 days (89% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Iberville County have?
In 2025, Iberville County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 105.
Is the air quality in Iberville County getting better or worse?
Air quality in Iberville County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 306 good days. Worst year: 2025 with 214 good days.
What does AQI 41 mean for health?
Iberville 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 Iberville County compare to other counties in Louisiana?
Iberville County has 78.4% good air days. Nearby counties in Louisiana: Ascension (94.1% good), Bossier (86.5% good), Caddo (84.3% good), Calcasieu (61.5% good), East Baton Rouge (49.3% good), Jefferson (58.6% good).
What is the 90th percentile AQI in Iberville County?
The 90th percentile AQI for Iberville County is 61, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 105 (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.