Saint Charles, IL
Long-term air quality
What this page tells you
This page combines annual PM2.5, unhealthy days, 5-year trend, and data coverage so you can compare long-term air quality, not just today's reading.
Saint Charles, IL air quality summary: Saint Charles, IL has a clean air score of 71.3 and a B grade, indicating good air quality. The city's annual PM2.5 mean is 8.2 µg/m³. Saint Charles recorded an annual PM2.5 mean of 8.2, which is considered moderate or acceptable but still relevant for long-term exposure. Long-term air quality in Saint Charles has been improving over recent years.
Clean Air Score
A clean air score of 71.3 and a B grade signify healthy air quality over the long term. These ratings show that particulate levels are generally low and well within safe limits for residents.
🏡 What This Means for Buying
Air quality should be seen as a positive attribute when considering a home in Saint Charles. The B grade indicates a stable environment with favorable particulate levels.
Indoor Air Quality in Saint Charles, IL
Outdoor pollution can still affect indoor air when windows are open, filtration is weak, or wildfire smoke moves in.
How to react when today's AQI changes
Use the AQI bands below to decide whether to open windows, run an air purifier, or stay indoors when pollution spikes in Saint Charles.
AQI 0-50
GoodOpen windows: Open windows if you want fresh air.
Air purifier: No purifier needed for most homes.
Indoor activity: Normal indoor activity is fine.
AQI 51-100
ModerateOpen windows: Sensitive groups should limit open-window time.
Air purifier: Use fans or filtration if dust or pollen is bothering you.
Indoor activity: Most people can stay active indoors.
AQI 101-150
Unhealthy for Sensitive GroupsOpen windows: Keep windows closed.
Air purifier: Run a HEPA purifier in the main room and bedroom.
Indoor activity: Sensitive groups should reduce outdoor exposure.
AQI 151+
UnhealthyOpen windows: Keep windows and doors closed.
Air purifier: Run HEPA continuously and seal obvious drafts.
Indoor activity: Stay indoors as much as possible; use an N95 if you must go out.
Common indoor air concerns in Saint Charles:
- Seasonal pollen and dust mite allergens
- VOCs from household products
Recommended action: If today's AQI reaches 101 or higher, close windows and run HEPA filtration before indoor air starts to feel smoky or stale.
Top Products for Saint Charles Homes:
🩺 My Health Risk Assessment
See how Saint Charles's air quality affects you and your family specifically.
Health Advice
Good for most outdoor activities.
Add Saint Charles Air Quality to your site
Perfect for local news, real estate blogs, and community pages.
</> Create Free Widget🏡 Property Value Impact Analysis
Between 2019 and 2024, Saint Charles's air quality improved by 2 μg/m³. Based on NBER studies, this change correlates with a estimated 8% increase in relative property value retention.
Cleaner Alternatives in IL
Why Saint Charles earned a 71.3
Raw inputs, scoring weights, and data coverage for this city.
Best Time to Run
Find the cleanest hours for your run today.
Cycling Forecast
Avoid pollution spikes on your next ride.
📅 Past 30 Days Trend
Real-time daily PM2.5 AQI
🌸 Pollen Outlook
Current Seasonal Forecast
How it worksBased on current seasonal forecast data. Not a long-term pollution rating or relocation score.
Score Breakdown
| Component | Weight | Score Contribution |
|---|---|---|
| Annual Air Quality | 40% | 55 |
| Unhealthy Days | 25% | 100 |
| 5-Year Trend | 20% | 60 |
| Seasonal Variability | 10% | 93.6 |
| Extreme Events | 5% | 100 |
Explore More Air Quality Data
Frequently Asked Questions
About This Data
Data Sources
Historical air quality mapping and scoring are based completely on official U.S. Environmental Protection Agency (EPA) AirNow API data. 5-day AQI forecasts are provided by WAQI.
Methodology
Our Clean Air Score (0-100) is a proprietary algorithm that weighs multiple factors:
- Annual PM2.5 averages (40%)
- Frequency of unhealthy days (25%)
- 5-year pollution trends (20%)
- Seasonal variability and extreme events (15%)
Updates & Accuracy
Real-time data is updated hourly. Historical aggregate scores are recalculated monthly to reflect the latest trends. While we strive for accuracy, sensor maintenance and local conditions can affect individual readings.
Practical Advice
When AQI > 100: Sensitive groups (children, elderly, asthmatics) should limit prolonged outdoor exertion.
When AQI > 150: Everyone should avoid outdoor exercise and keep windows closed.
More Cities in IL
Similar Rankings Nationwide
Saint Charles Air Quality FAQs
Is Saint Charles a good fit for people who care about long-term air quality?
Saint Charles is a strong option with a clean air score of 71.3 and a B grade. Its annual PM2.5 mean of 8.2 supports a generally healthy and clean environment.
What is the frequency of unhealthy air or long-term pollution exposure in Saint Charles?
Saint Charles reports 0% unhealthy days, which aligns with its B grade and healthy PM2.5 mean of 8.2. This indicates a consistent track record of clean air.
Is air quality in Saint Charles improving or getting worse over time?
The air quality trend in Saint Charles has been improving over recent years. This positive trajectory is a good sign for long-term environmental stability.
How does air quality vary within Saint Charles?
Air quality can vary within the city due to local traffic, industry, and location patterns. Proximity to transit routes and local industrial activity can lead to localized variations.