Metro area air quality · 2024

Dayton, OH

Median AQI 47 (Good). 59.6% of monitored days rated Good across this metro's EPA monitoring network.

47
Median AQI
59.6%
Good-air days
0
Unhealthy days
25%
Cleaner than US metros

Aggregated from EPA Air Quality System (2024), 366 monitored days. EPA AQS →

Insights: Dayton, OH metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 47 over 366 measured days in 2024, which corresponds to a Good band and a Moderate metro-wide health grade. The monitored-day split lands at 218 Good days (60%), 144 Moderate (39%), and 4 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 67 while the highest single-day reading hit 147 (USG). Metro residents averaged roughly 17.9 clean-air days per 30-day window across the reporting year.

Across the 2020–2024 trend window, good days shifted by +50 and the median AQI moved -5 points, which classifies the multi-year trajectory as improving. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Baltimore-Columbia-Towson, MD (58.7% good, AQI 47); Bartlesville, OK (57.2% good, AQI 47); Columbia, SC (57.4% good, AQI 47).

Air Quality Summary

Median AQI

47

Good

Good Days

59.6%

218 of 366 days

Max AQI

147

USG

Health Grade

Moderate

90th pct: 67

AQI Day Breakdown (2024)

Distribution of 366 monitored days across EPA AQI categories.

Good

218

60%

Moderate

144

39%

USG

4

1%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Dayton, OH metro area's air quality is rated Moderate based on 59.6% good air days. No unhealthy air days were recorded in 2024.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the Dayton, OH metro compare?

How Dayton, OH compares

Good-day share worse than US avg
Dayton, OH 59.6%
Baltimore-Columbia-Towson, MD 58.7%
US average 70.2%
Median AQI worse than US avg
Dayton, OH 47
Baltimore-Columbia-Towson, MD 47
US average 41
Unhealthy days / yr better than US avg
Dayton, OH 0
Baltimore-Columbia-Towson, MD 1
US average 1

5-Year Air Quality Trend

Air quality is improving in the Dayton, OH metro. Best year: 2024 (218 good days).

Year Good Moderate Unhealthy Median AQI
2020 168 194 0 52
2021 156 208 0 53
2022 196 166 0 49
2023 178 174 2 51
2024 218 144 0 47

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Dayton, OH.

Baltimore-Columbia-Towson, MD

AQI 47 · 58.7% good

47

Bartlesville, OK

AQI 47 · 57.2% good

47

Columbia, SC

AQI 47 · 57.4% good

47

Florence, SC

AQI 47 · 61.4% good

47

Fort Wayne, IN

AQI 47 · 59.3% good

47

Gadsden, AL

AQI 47 · 58.6% good

47

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Air Quality Guides

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Health Effects of Air Pollution

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Frequently Asked Questions

What is the air quality in the Dayton, OH metro area? ▼
The Dayton, OH metro area has a median Air Quality Index (AQI) of 47, rated "Good." 59.6% of monitored days (218 out of 366) had good air quality in 2024.
How many unhealthy air days does Dayton, OH have? ▼
In 2024, the Dayton, OH metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 147.
Is air quality in Dayton, OH getting better or worse? ▼
Air quality in the Dayton, OH metro is improving based on 5-year trends (2020-2024). Best year: 2024 with 218 good days. Worst year: 2021 with 156 good days.
What does AQI 47 mean for health? ▼
An AQI of 47 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for Dayton, OH? ▼
The 90th percentile AQI for the Dayton, OH metro area is 67, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 147 (USG).
How does Dayton, OH compare to other metro areas? ▼
The Dayton, OH metro has 59.6% good air days. Similar metros: Baltimore-Columbia-Towson, MD (58.7% good), Bartlesville, OK (57.2% good), Columbia, SC (57.4% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2024. The AQS collects ambient air monitoring data from state, local, and tribal monitoring agencies across the United States.

Metrics: Air Quality Index (AQI) is calculated using EPA-standard breakpoints for six criteria pollutants: PM2.5, PM10, Ozone, NO2, CO, and SO2. Median AQI, max AQI, and 90th percentile AQI are computed from daily measurements. Good days percentage reflects days with AQI 0–50.

Coverage: 501 metro areas (Core Based Statistical Areas). Only metros with active monitoring stations are included. Unmonitored areas are not represented.

Read our methodology , how this data is sourced, computed, and verified.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary files (metro-level) · 2020–2024