Median AQI
49
Good
Utah · County air quality · 2025
Utah County, Utah
Median AQI 49 (Good). 54.0% of monitored days rated Good, direct from EPA Air Quality System stations.
- 49
- Median AQI
- 54.0%
- Good-air days
- 0
- Unhealthy days
- 9%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Utah County's air is good on balance, among the most polluted counties nationally, a median AQI of 49 with 54.0% of 304 monitored days in the Good band, driven mainly by Ozone.
- 49
- median AQI · Good
- 54.0%
- days rated Good
- Ozone
- main pollutant
- 9%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 109.
Data updated July 2026
- Good · 164 d · 53.9%
- Moderate · 139 d · 45.7%
- USG · 1 d · 0.3%
How did Utah County's air break down in 2025?
Across 304 monitored days, 164 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 109 (USG).
EPA AQS →Air quality data from EPA Air Quality System (2025). 304 days monitored. Median AQI: 49 (Good).
Insights: Utah County, Utah. EPA monitors recorded a median Air Quality Index of 49 across 304 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 164 (54%) fell in the Good band (AQI 0–50), 139 (46%) registered Moderate readings, and 1 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 75, while the worst single-day peak hit 109 (USG). Residents averaged about 16.2 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (197 days), PM2.5 (101 days), PM10 (3 days), NO2 (3 days). Across the 2020–2025 trend window, good days shifted by -35 and the median AQI moved +1 points, placing the multi-year trajectory at stable. The worst single reading over the 2020–2025 window was AQI 109, usg but never Unhealthy. Nearby counties show comparable readings: Box Elder (60.0% good, AQI 48); Cache (61.2% good, AQI 46); Carbon (62.9% good, AQI 47); Davis (59.5% good, AQI 48); Duchesne (59.4% good, AQI 47); Garfield (100.0% good, AQI 4).
Air Quality Summary
Good Days
54.0%
164 of 304 monitored days
-21.0pp vs 75% target
Max AQI Recorded
109
USG
Health Grade
Moderate
90th-pct AQI 75
Utah County, Good days share 53.9%
National avg
Share of monitored days at AQI 0-50 (Good band).
Utah 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 304 monitored days across EPA AQI categories.
Good
164
54%
Moderate
139
46%
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 Utah County.
- Ozone · 197 days · 64.8%
- PM2.5 · 101 days · 33.2%
- PM10 · 3 days · 1.0%
- NO₂ · 3 days · 1.0%
Health Impact Assessment
Moderate
Utah County's air quality is rated Moderate based on 54.0% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 54.0% of monitored days in 2025, with a median AQI of 49. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 197 of 304 monitored days.
5-Year Air Quality Trend
Air quality is stable in Utah County. Best year: 2024 (210 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 199 | 162 | 5 | 0 | 48 | 150 |
| 2021 | 192 | 156 | 17 | 0 | 49 | 144 |
| 2022 | 206 | 154 | 5 | 0 | 49 | 119 |
| 2023 | 201 | 163 | 1 | 0 | 48 | 104 |
| 2024 | 210 | 147 | 8 | 1 | 47 | 151 |
| 2025 | 164 | 139 | 1 | 0 | 49 | 109 |
How does Utah County compare?
How Utah County compares
Good-day share worse than US avg
Utah County 54.0%
Box Elder County, Utah 60.0%
US average 76.5%
Median AQI worse than US avg
Utah County 49
Box Elder County, Utah 48
US average 38
Unhealthy days / yr about average
Utah County 0
Box Elder County, Utah 0
US average 0
Other Counties in Utah
Air quality comparison for nearby counties in Utah.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Utah County.
Allegheny County, Pennsylvania
AQI 49 · 51.6% good
Arkansas County, Arkansas
AQI 49 · 51.6% good
Ashley County, Arkansas
AQI 49 · 53.9% good
Clayton County, Georgia
AQI 49 · 53.1% good
Cleveland County, Oklahoma
AQI 49 · 53.7% good
Dewey County, Oklahoma
AQI 49 · 56.6% good
What Utah 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 49 means for exposure. Health guidance
- See how Utah County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Utah County with its Utah neighbours before drawing a conclusion about the region. All of Utah
Based on 304 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 Utah County, Utah? ▼
Utah County has a median Air Quality Index (AQI) of 49, rated "Good." 54.0% of monitored days (164 out of 304) had good air quality in 2025.
What is the main pollutant in Utah County? ▼
The primary pollutant in Utah County is Ozone (O3), which was the main AQI driver on 197 days (65% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Utah County have? ▼
In 2025, Utah County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 109.
Is the air quality in Utah County getting better or worse? ▼
Air quality in Utah County is stable based on 5-year trends (2020-2025). Best year: 2024 with 210 good days. Worst year: 2025 with 164 good days.
What does AQI 49 mean for health? ▼
Utah County's median AQI of 49 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 Utah County compare to other counties in Utah? ▼
Utah County has 54.0% good air days. Nearby counties in Utah: Box Elder (60.0% good), Cache (61.2% good), Carbon (62.9% good), Davis (59.5% good), Duchesne (59.4% good), Garfield (100.0% good).
What is the 90th percentile AQI in Utah County? ▼
The 90th percentile AQI for Utah County is 75, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 109 (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.