Air Quality Legend
Air quality describes how clean or polluted the air is, and how it can affect our health. At AIROMAP, we display key pollutants—both particulate matter and gases—to help you make informed decisions about your environment and well-being.
Measured Pollutants
Particulates
Particles in the air can vary in size. Smaller particles (PM2.5) can penetrate deeper into the lungs, while larger ones (PM10) can irritate airways.
Typical Guidance:
Normal: PM2.5 ≤ 12 µg/m³ and PM10 ≤ 50 µg/m³
Elevated:: PM2.5 = 12.1 – 35.4 µg/m³; PM10 = 51 – 150 µg/m³
High:: PM2.5 > 35.4 µg/m³; PM10 > 150 µg/m³
Gases
We track several gases that can impact air quality, health, and the environment.
Nitrogen Dioxide (NO₂):
Can irritate airways; higher levels pose greater risks for people with asthma or lung conditions.
Ozone (O₃):
Ground-level ozone can trigger breathing difficulties, especially for sensitive groups.
Sulfur Dioxide (SO₂):
Major contributor to acid rain and can cause respiratory problems at higher concentrations.
Carbon Monoxide (CO):
Reduces oxygen in the bloodstream. Prolonged high exposure can be dangerous.
Typical Guidance:
NO₂ (ppb): Normal ≤ 53; Elevated 54 – 100; High > 100
O₃ (ppb): Normal ≤ 70; Elevated 71 – 85; High > 85
SO₂ (ppb): Keep as low as possible; short-term spikes above ~75 ppb can be harmful
CO (ppm): Normal ≤ 4.4; Elevated 4.5 – 9.4; High > 9.4
Air Quality Index (UAQI) Overview
All measured pollutants feed into a single Air Quality Index (UAQI) to provide an at-a-glance summary. Hover over any location on the AIROMAP for real-time UAQI readings.
| UAQI Level | Range | Label | Health Considerations |
|---|---|---|---|
| Excellent | 80 – 100 | Excellent air quality | Air is very clean and safe. No precautions necessary. |
| Good | 60 – 79 | Good air quality | Air is generally safe, but very sensitive individuals may experience minor effects. |
| Moderate | 40 – 59 | Moderate air quality | Some pollutants may be a concern for very sensitive individuals. |
| Low | 20 – 39 | Low air quality | May cause discomfort or minor health effects, especially for sensitive groups. |
| Poor | 1 – 19 | Poor air quality | Everyone may experience adverse effects. Limit outdoor exposure. |
| Very Poor | 0 | Very Poor air quality | Severe health risks. Stay indoors and use air purification if available. |
UAQI Forecast
Our UAQI Forecast leverages real-time data and predictive models to estimate how air quality may change in the coming hours or days. Check the Forecast section to plan outdoor activities safely and proactively.
Historical Data
Review Historical Data to see how pollutant levels have changed over time. This helps you identify trends, spot potential pollution sources, and better understand seasonal or weather-related fluctuations in air quality.
What These Numbers Mean for You
Normal (Good): Enjoy outdoor activities; minimal health risk.
Elevated (Moderate): Sensitive groups should monitor symptoms; others generally safe.
High (Unhealthy – Very High): Reduce time outdoors, especially if you have respiratory or heart conditions.
Hazardous: Everyone should stay indoors and follow official health advisories.