Louisiana · County air quality · 2025

Livingston County, Louisiana

Median AQI 45 (Good). 62.0% of monitored days rated Good, direct from EPA Air Quality System stations.

45
Median AQI
62.0%
Good-air days
0
Unhealthy days
18%
Cleaner than US counties

Livingston County's 2025 annual median AQI is 45 (Good), with 62.0% Good days

According to the U.S. EPA Air Quality System, Livingston County, Louisiana posted a 2025 median AQI of 45 (Good) across 363 monitored days, with 62.0% rated Good and 0 unhealthy or worse. This is an annual comparison, not today's advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US
Livingston County's 62.0% Good-day share places it cleaner than 18% of US counties in 2025.
Closest median-AQI peer
Baltimore County (64.7% Good, median AQI 45) is the closest nationwide median-AQI peer to Livingston County.
2020–2025 trend
Livingston County's floor-qualifying Good-day share is improving from 2020 to 2025 (58.0% → 62.0%).
Median AQI
Median AQI: 45

The verdict

According to EPA Air Quality System monitoring data, Livingston County's air is good on balance, among the more polluted 10% of US counties, a median AQI of 45 with 62.0% of 363 monitored days in the Good band, driven mainly by PM2.5.

45
median AQI · Good
62.0%
days rated Good
PM2.5
main pollutant
18%
cleaner than US counties

Not one day crossed into the Unhealthy tier; the worst single reading was AQI 90.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Livingston County's Good-day share fell from 64.2% to 62.0% between the 2024 and 2025 EPA annual releases, a change of -2.2 percentage points.
  • Livingston County's peak single-day AQI fell from 100 to 90 between the 2024 and 2025 EPA annual releases, a change of -10 points.

Compared against 366 monitored days in 2024 and 363 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Data updated August 2026

Livingston 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 363 monitored days G M Median AQI 45 0 50 100 150 200 300 500 Livingston County
  • Good · 225 d · 62.0%
  • Moderate · 138 d · 38.0%

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

Across 363 monitored days, 225 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 90 (Moderate).

EPA AQS →

Air quality data from EPA Air Quality System (2025). 363 days monitored. Median AQI: 45 (Good).

Insights: Livingston County, Louisiana. EPA monitors recorded a median Air Quality Index of 45 across 363 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 225 (62%) fell in the Good band (AQI 0–50), 138 (38%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 59, while the worst single-day peak hit 90 (Moderate). Residents averaged about 18.6 clean-air days per 30-day window during the monitoring year.

The full pollutant mix ranks as PM2.5 (237 days), Ozone (124 days), NO2 (2 days). Across the 2020–2025 trend window, the share of monitored days rated Good shifted by +4.0 points and the median AQI moved -2 points, placing the multi-year trajectory at improving. The worst single reading over the 2020–2025 window was AQI 90, moderate but never Unhealthy. Nearby counties show comparable readings: Ascension (95.6% good, AQI 33); Bossier (78.9% good, AQI 42); Caddo (80.0% good, AQI 38); Calcasieu (62.2% good, AQI 47); East Baton Rouge (49.6% good, AQI 51); Iberville (78.6% good, AQI 40).

Air Quality Summary

Median AQI

45

Good

Good Days

62.0%

225 of 363 monitored days

-13.0pp vs 75% target

Max AQI Recorded

90

Moderate

Health Grade

Moderate

90th-pct AQI 59

Livingston County, Good days share 62.0%
National avg

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

Livingston 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 363 monitored days across EPA AQI categories.

Good

225

62%

Moderate

138

38%

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 Livingston County.

Livingston 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. PM2.5 · 65.3% Ozone · 34.2% 0% 25% 50% 75% 100% Livingston County, Louisiana · 363 monitored days Criteria pollutant column
  • PM2.5 · 237 days · 65.3%
  • Ozone · 124 days · 34.2%
  • NO₂ · 2 days · 0.6%
Fine Particles (PM2.5) 237 days (65%)

How PM2.5 affects health →

Ozone (O3) 124 days (34%)

How Ozone affects health →

Nitrogen Dioxide (NO2) 2 days (1%)

How NO2 affects health →

Health Impact Assessment

Moderate

Livingston County's air quality is rated Moderate based on 62.0% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 62.0% of monitored days in 2025, with a median AQI of 45. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is PM2.5, driving AQI on 237 of 363 monitored days.

5-Year Air Quality Trend

Air quality is improving in Livingston County. Highest Good-day share: 2024 (64.2%, 235 of 366 monitored days).

Year Good Moderate USG Unhealthy Median AQI
2020 206 148 1 0 47
2021 186 161 1 0 48
2022 177 181 3 0 51
2023 134 225 5 0 54
2024 235 131 0 0 44
2025 225 138 0 0 45

How does Livingston County compare?

How Livingston County compares

Good-day share worse than US avg
Livingston County 62.0%
Baltimore County, Maryland 64.7%
US average 76.0%
Median AQI worse than US avg
Livingston County 45
Baltimore County, Maryland 45
US average 39
Unhealthy days / yr better than US avg
Livingston County 0
Baltimore County, Maryland 0
US average 1

Counties with a similar median AQI

Nationwide peers within about the same annual median AQI as Livingston County (45), not geographic neighbors.

Same primary pollutant: PM2.5

PM2.5 led the AQI on the most monitored days here. These peers share that driver and the closest Good-day share (a second relationship type beyond median-AQI neighbors).

Louisiana counties on the map

Geographic containment only, other monitored counties in Louisiana, independent of AQI or pollutant match.

What Livingston 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 45 means for exposure. Health guidance
  • See how Livingston County ranks against every monitored U.S. county on Good-day share. County rankings
  • Compare Livingston County with its Louisiana neighbours before drawing a conclusion about the region. All of Louisiana

Based on 363 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.

Keep exploring the annual AQI record

Air-quality reading list

Frequently Asked Questions

What is the air quality in Livingston County, Louisiana?
Livingston County has a median Air Quality Index (AQI) of 45, rated "Good." 62.0% of monitored days (225 out of 363) had good air quality in 2025.
What is the main pollutant in Livingston County?
The primary pollutant in Livingston County is Fine Particles (PM2.5), which was the main AQI driver on 237 days (65% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Livingston County have?
In 2025, Livingston County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 90.
Is the air quality in Livingston County getting better or worse?
Air quality in Livingston County is improving across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2024 at 64.2% (235 of 366 days). Lowest qualifying Good-day share: 2023 at 36.8% (134 of 364 days).
What does AQI 45 mean for health?
Livingston County's median AQI of 45 falls in the "Good" category. See the AQI category guide for what each range means for health.
How does Livingston County compare to other counties in Louisiana?
Livingston County has 62.0% good air days. Nearby counties in Louisiana: Ascension (95.6% good), Bossier (78.9% good), Caddo (80.0% good), Calcasieu (62.2% good), East Baton Rouge (49.6% good), Iberville (78.6% good).
What is the 90th percentile AQI in Livingston County?
The 90th percentile AQI for Livingston County is 59, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 90 (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. Spotted a figure that looks wrong? Report a correction.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Livingston County, Louisiana · 2020–2025

Share this annual record

Send the source-year summary or download its ready-to-use data card.

XFacebookLinkedInWhatsAppEmail
Embed this widget

Copy this snippet to embed a live-linked card on your own site. Attribution to PlainAirData is baked into the widget.

Download this county's annual AQI row as CSV , with the same EPA fields and denominator shown on this page.

Every figure on PlainAirData 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.