Ohio · County air quality · 2025

Lawrence County, Ohio

Median AQI 43 (Good). 70.3% of monitored days rated Good, direct from EPA Air Quality System stations.

43
Median AQI
70.3%
Good-air days
0
Unhealthy days
32%
Cleaner than US counties

The verdict

According to EPA Air Quality System monitoring data, Lawrence County's air is good on balance, more polluted than the median US county, a median AQI of 43 with 70.3% of 273 monitored days in the Good band, driven mainly by Ozone.

43
median AQI · Good
70.3%
days rated Good
Ozone
main pollutant
32%
cleaner than US counties

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

Data updated July 2026

Lawrence 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 43 0 50 100 150 200 300 500 Lawrence County
  • Good · 192 d · 70.3%
  • Moderate · 81 d · 29.7%

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

Across 273 monitored days, 192 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). 273 days monitored. Median AQI: 43 (Good).

Insights: Lawrence County, Ohio. EPA monitors recorded a median Air Quality Index of 43 across 273 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 192 (70%) fell in the Good band (AQI 0–50), 81 (30%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 61, while the worst single-day peak hit 90 (Moderate). Residents averaged about 21.1 clean-air days per 30-day window during the monitoring year.

The full pollutant mix ranks as Ozone (147 days), PM2.5 (126 days). Across the 2020–2025 trend window, good days shifted by -87 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 90, moderate but never Unhealthy. Nearby counties show comparable readings: Allen (65.9% good, AQI 43); Ashtabula (81.2% good, AQI 43); Athens (80.3% good, AQI 33); Belmont (63.0% good, AQI 42); Butler (33.3% good, AQI 55); Clark (59.4% good, AQI 46).

Air Quality Summary

Median AQI

43

Good

Good Days

70.3%

192 of 273 monitored days

-4.7pp vs 75% target

Max AQI Recorded

90

Moderate

Health Grade

Moderate

90th-pct AQI 61

Lawrence County, Good days share 70.3%
National avg

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

Lawrence 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

192

70%

Moderate

81

30%

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 Lawrence County.

Lawrence County, Ohio 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 · 53.8% PM2.5 · 46.2% 0% 25% 50% 75% 100% Lawrence County, Ohio · 273 monitored days Criteria pollutant column
  • Ozone · 147 days · 53.8%
  • PM2.5 · 126 days · 46.2%
Ozone (O3) 147 days (54%)

How Ozone affects health →

Fine Particles (PM2.5) 126 days (46%)

How PM2.5 affects health →

Health Impact Assessment

Moderate

Lawrence County's air quality is rated Moderate based on 70.3% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 70.3% of monitored days in 2025, with a median AQI of 43. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is Ozone, driving AQI on 147 of 273 monitored days.

5-Year Air Quality Trend

Air quality is worsening in Lawrence County. Best year: 2020 (279 good days).

Year Good Moderate USG Unhealthy Median AQI
2020 279 75 0 0 40
2021 210 155 0 0 46
2022 220 141 0 0 45
2023 225 134 4 2 46
2024 264 102 0 0 43
2025 192 81 0 0 43

How does Lawrence County compare?

How Lawrence County compares

Good-day share worse than US avg
Lawrence County 70.3%
Allen County, Ohio 65.9%
US average 76.5%
Median AQI worse than US avg
Lawrence County 43
Allen County, Ohio 43
US average 38
Unhealthy days / yr about average
Lawrence County 0
Allen County, Ohio 0
US average 0

Other Counties in Ohio

Air quality comparison for nearby counties in Ohio.

Counties with Similar Air Quality

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

What Lawrence 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 43 means for exposure. Health guidance
  • See how Lawrence County ranks against every monitored U.S. county on Good-day share. County rankings
  • Compare Lawrence County with its Ohio neighbours before drawing a conclusion about the region. All of Ohio

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 Lawrence County, Ohio?
Lawrence County has a median Air Quality Index (AQI) of 43, rated "Good." 70.3% of monitored days (192 out of 273) had good air quality in 2025.
What is the main pollutant in Lawrence County?
The primary pollutant in Lawrence County is Ozone (O3), which was the main AQI driver on 147 days (54% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Lawrence County have?
In 2025, Lawrence County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 90.
Is the air quality in Lawrence County getting better or worse?
Air quality in Lawrence County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 279 good days. Worst year: 2025 with 192 good days.
What does AQI 43 mean for health?
Lawrence County's median AQI of 43 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 Lawrence County compare to other counties in Ohio?
Lawrence County has 70.3% good air days. Nearby counties in Ohio: Allen (65.9% good), Ashtabula (81.2% good), Athens (80.3% good), Belmont (63.0% good), Butler (33.3% good), Clark (59.4% good).
What is the 90th percentile AQI in Lawrence County?
The 90th percentile AQI for Lawrence County is 61, 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.

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.