Median AQI
41
Good
Missouri · County air quality · 2025
Sainte Genevieve County, Missouri
Median AQI 41 (Good). 91.4% of monitored days rated Good, direct from EPA Air Quality System stations.
- 41
- Median AQI
- 91.4%
- Good-air days
- 0
- Unhealthy days
- 83%
- Cleaner than US counties
Sainte Genevieve County's 2025 annual median AQI is 41 (Good), with 91.4% Good days
According to the U.S. EPA Air Quality System, Sainte Genevieve County, Missouri posted a 2025 median AQI of 41 (Good) across 255 monitored days, with 91.4% 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
- Sainte Genevieve County's 91.4% Good-day share places it cleaner than 83% of US counties in 2025.
- Closest median-AQI peer
- Armstrong County (70.5% Good, median AQI 41) is the closest nationwide median-AQI peer to Sainte Genevieve County.
- 2020–2025 trend
- Sainte Genevieve County's floor-qualifying Good-day share is stable from 2020 to 2025 (93.5% → 91.4%).
- Median AQI
- Median AQI: 41
The verdict
According to EPA Air Quality System monitoring data, Sainte Genevieve County's air is good on balance, cleaner than most US counties, a median AQI of 41 with 91.4% of 255 monitored days in the Good band, driven mainly by Ozone.
- 41
- median AQI · Good
- 91.4%
- days rated Good
- Ozone
- main pollutant
- 83%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 108.
Data updated August 2026
- Good · 233 d · 91.4%
- Moderate · 20 d · 7.8%
- USG · 2 d · 0.8%
How did Sainte Genevieve County's air break down in 2025?
Across 255 monitored days, 233 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 108 (USG).
EPA AQS →Air quality data from EPA Air Quality System (2025). 255 days monitored. Median AQI: 41 (Good).
Insights: Sainte Genevieve County, Missouri. EPA monitors recorded a median Air Quality Index of 41 across 255 measured days in 2025, earning a Good classification and a Excellent health grade. Of those days, 233 (91%) fell in the Good band (AQI 0–50), 20 (8%) registered Moderate readings, and 2 (1%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 50, while the worst single-day peak hit 108 (USG). Residents averaged about 27.4 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (255 days). Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -2.1 points and the median AQI moved +5 points, placing the multi-year trajectory at stable. The worst single reading over the 2020–2025 window was AQI 108, usg but never Unhealthy. Nearby counties show comparable readings: Andrew (86.9% good, AQI 40); Boone (93.2% good, AQI 37); Buchanan (56.4% good, AQI 46); Callaway (89.6% good, AQI 41); Cass (77.6% good, AQI 41); Cedar (81.6% good, AQI 39).
Air Quality Summary
Good Days
91.4%
233 of 255 monitored days
16.4pp vs 75% target
Max AQI Recorded
108
USG
Health Grade
Excellent
90th-pct AQI 50
Sainte Genevieve County, Good days share 91.4%
National avg
Share of monitored days at AQI 0-50 (Good band).
Sainte Genevieve 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 255 monitored days across EPA AQI categories.
Good
233
91%
Moderate
20
8%
USG
2
1%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Sainte Genevieve County.
- Ozone · 255 days · 100.0%
Health Impact Assessment
Excellent
Sainte Genevieve County's air quality is rated Excellent based on 91.4% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 91.4% 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 255 of 255 monitored days.
5-Year Air Quality Trend
Air quality is stable in Sainte Genevieve County. Highest Good-day share: 2020 (93.5%, 229 of 245 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 229 | 16 | 0 | 0 | 36 | 87 |
| 2021 | 227 | 18 | 0 | 0 | 39 | 100 |
| 2022 | 215 | 29 | 0 | 0 | 41 | 100 |
| 2023 | 195 | 38 | 12 | 0 | 44 | 147 |
| 2024 | 225 | 23 | 0 | 0 | 43 | 100 |
| 2025 | 233 | 20 | 2 | 0 | 41 | 108 |
How does Sainte Genevieve County compare?
How Sainte Genevieve County compares
Good-day share better than US avg
Sainte Genevieve County 91.4%
Armstrong County, Pennsylvania 70.5%
US average 76.0%
Median AQI worse than US avg
Sainte Genevieve County 41
Armstrong County, Pennsylvania 41
US average 39
Unhealthy days / yr better than US avg
Sainte Genevieve County 0
Armstrong County, Pennsylvania 0
US average 1
Counties with a similar median AQI
Nationwide peers within about the same annual median AQI as Sainte Genevieve County (41), not geographic neighbors.
Armstrong County, Pennsylvania
Median AQI 41 · 70.5% Good-day share
Benewah County, Idaho
Median AQI 41 · 63.4% Good-day share
Berrien County, Michigan
Median AQI 41 · 80.9% Good-day share
Callaway County, Missouri
Median AQI 41 · 89.6% Good-day share
Cambria County, Pennsylvania
Median AQI 41 · 74.5% Good-day share
Cass County, Missouri
Median AQI 41 · 77.6% Good-day share
Same primary pollutant: Ozone
Ozone 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).
Shelby County, Alabama
91.4% Good-day share · median AQI 36
Shelby County, Indiana
91.4% Good-day share · median AQI 35
Monmouth County, New Jersey
91.3% Good-day share · median AQI 36
Anderson County, South Carolina
91.3% Good-day share · median AQI 40
Fond du Lac County, Wisconsin
91.5% Good-day share · median AQI 37
Knox County, Indiana
91.3% Good-day share · median AQI 36
Missouri counties on the map
Geographic containment only, other monitored counties in Missouri, independent of AQI or pollutant match.
What Sainte Genevieve 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 Sainte Genevieve County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Sainte Genevieve County with its Missouri neighbours before drawing a conclusion about the region. All of Missouri
Based on 255 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 Sainte Genevieve County, Missouri? ▼
Sainte Genevieve County has a median Air Quality Index (AQI) of 41, rated "Good." 91.4% of monitored days (233 out of 255) had good air quality in 2025.
What is the main pollutant in Sainte Genevieve County? ▼
The primary pollutant in Sainte Genevieve County is Ozone (O3), which was the main AQI driver on 255 days (100% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Sainte Genevieve County have? ▼
In 2025, Sainte Genevieve County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 108.
Is the air quality in Sainte Genevieve County getting better or worse? ▼
Air quality in Sainte Genevieve County is stable across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2020 at 93.5% (229 of 245 days). Lowest qualifying Good-day share: 2023 at 79.6% (195 of 245 days).
What does AQI 41 mean for health? ▼
Sainte Genevieve County's median AQI of 41 falls in the "Good" category. See the AQI category guide for what each range means for health.
How does Sainte Genevieve County compare to other counties in Missouri? ▼
Sainte Genevieve County has 91.4% good air days. Nearby counties in Missouri: Andrew (86.9% good), Boone (93.2% good), Buchanan (56.4% good), Callaway (89.6% good), Cass (77.6% good), Cedar (81.6% good).
What is the 90th percentile AQI in Sainte Genevieve County? ▼
The 90th percentile AQI for Sainte Genevieve County is 50, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 108 (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. Spotted a figure that looks wrong? Report a correction.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Sainte Genevieve County, Missouri · 2020–2025
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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.