Pleasant Hill, Missouri Air Quality
Pleasant Hill air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now
Pleasant Hill, MO · Air quality right now
The air quality index in Pleasant Hill, MO is 31 (Good) right now — safe for outdoor activity.
Is it safe to be outside in Pleasant Hill today?
AQI 31 Yes — air quality is Good
Air is clean — great for outdoor activity.Main pollutant: PM2.5Observed 10:00 AM CDT
Pollutants right now
- PM2.52.5 µg/m³Main pollutantfine particles — smoke, exhaust, soot
- PM102.5 µg/m³coarse particles — dust, pollen, ash
- Ozone31 µg/m³smog — builds on hot, sunny days
- NO₂9.4 µg/m³nitrogen dioxide — traffic, combustion
ExerciseOK to run — no air-quality limits on outdoor exercise.
How to read Pleasant Hill’s air quality
Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.
Air quality over time in Pleasant Hill
Across the EPA’s county records from 2020 to 2025, Pleasant Hill’s cleanest year was 2020 (median AQI 39) and its most polluted was 2023 (median AQI 44); the typical (median) day has trended more polluted since 2020.
| Year | Median AQI | Unhealthy+ | Main pollutant | USG | Moderate | Good |
|---|---|---|---|---|---|---|
| 2020 | 39 | 0 | PM2.5 | 2 | 60 | 300 |
| 2021 | 42 | 0 | PM2.5 | 1 | 97 | 267 |
| 2022 | 40 | 0 | Ozone | 0 | 73 | 287 |
| 2023 | 44 | 0 | Ozone | 5 | 85 | 242 |
| 2024 | 42 | 0 | Ozone | 1 | 85 | 280 |
| 2025 | 41 | 0 | PM2.5 | 1 | 80 | 281 |
“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 2020–2025.
Frequently asked
- What was the worst year for air quality in Pleasant Hill?
- In the EPA's 2020–2025 county records, 2023 had the most days above AQI 100: 5 days (5 Unhealthy for Sensitive Groups, 0 Unhealthy or worse). It also had the highest median AQI, 44.
- How many unhealthy air days does Pleasant Hill have?
- Across 2020–2025, under 1% of the days reported for Pleasant Hill's county had an AQI above 100 (10 of 2147), about 2 days a year. 2025 had 1 day.
- What's the main air pollutant in Pleasant Hill?
- PM2.5 drove Pleasant Hill's county AQI on the most days in 3 of 6 years (2020–2025); Ozone in 2022, 2023, 2024.