Gaithersburg, MD
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.
Gaithersburg, MD air quality summary: Gaithersburg, MD, achieves a clean air score of 88.9 and an overall grade of A. The annual mean for PM2.5 in the city is 4.5. Gaithersburg has an annual PM2.5 mean of 4.5. The long-term air quality in Gaithersburg is improving, indicating a positive environmental trajectory over recent years.
Clean Air Score
A clean air score of 88.9 and an A grade signify excellent long-term air quality in Gaithersburg. This indicates that particulate matter levels remain consistently low, providing a high-quality environmental setting for residents.
🏡 What This Means for Buying
For those evaluating Gaithersburg, the city's A-grade air quality serves as a positive indicator of long-term environmental health. Prospective residents can view these metrics as part of a comprehensive assessment of the area.
Indoor Air Quality in Gaithersburg, MD
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 Gaithersburg.
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 Gaithersburg:
- 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.
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🩺 My Health Risk Assessment
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Health Advice
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</> Create Free Widget🏡 Property Value Impact Analysis
Between 2019 and 2024, Gaithersburg's air quality improved by 1.9 μg/m³. Based on NBER studies, this change correlates with a estimated 7.6% increase in relative property value retention.
Cleaner Alternatives in MD
No cleaner cities found in this state. Gaithersburg is already a top performer!
Why Gaithersburg earned a 88.9
Raw inputs, scoring weights, and data coverage for this city.
Best Time to Run
Find the cleanest hours for your run today.
Cycling Forecast
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📅 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% | 100 |
| Unhealthy Days | 25% | 100 |
| 5-Year Trend | 20% | 59.5 |
| Seasonal Variability | 10% | 89.4 |
| 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.
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Gaithersburg Air Quality FAQs
Is Gaithersburg a good fit for people who care about long-term air quality?
Gaithersburg has a clean air score of 88.9 and an overall grade of A. With a PM2.5 annual mean of 4.5, the city is well-suited for those prioritizing high long-term air quality.
What is the frequency of unhealthy air or long-term pollution exposure in Gaithersburg?
Gaithersburg has an unhealthy days percentage of 0. This lack of unhealthy days reinforces the city's A grade and its low PM2.5 annual mean.
Is air quality in Gaithersburg improving or getting worse over time?
Air quality in Gaithersburg is improving. This means that long-term particulate levels have been trending downward over recent years.
Are there specific neighborhoods in Gaithersburg with better or worse air quality?
Air quality can vary within the city due to local traffic, industry, and location patterns. Localized factors like transit corridors can influence the specific conditions in different areas.