Air Quality Resources & Guides
Comprehensive guides to help you understand air quality, protect your health, and make informed decisions about outdoor activities.
Understanding Air Quality
Learn the basics of air quality measurement and what the numbers mean
What is the Air Quality Index (AQI)?
Learn how the AQI scale works and what different levels mean for your health
Read guide →How Air Quality is Measured
Discover the technology and methods used to monitor air pollution
Read guide →Reading Air Quality Reports
Understand forecasts, observed AQI readings, and what they mean for you
Read guide →Common Pollutants
Detailed information about the most common air pollutants
PM2.5: Fine Particulate Matter
The most dangerous air pollutant and its health effects
Read guide →Ozone (O3)
Ground-level ozone: sources, effects, and when it's worst
Read guide →PM10: Coarse Particles
Larger particles that can still affect your health
Read guide →Carbon Monoxide (CO)
The invisible, odorless gas that can be deadly
Read guide →Sulfur Dioxide (SO2)
A major pollutant from fossil fuel combustion
Read guide →Nitrogen Dioxide (NO2)
Traffic-related pollution and respiratory health
Read guide →Health & Protection
How air pollution affects health and what you can do about it
Health Effects of Air Pollution
Short-term and long-term health impacts of poor air quality
Read guide →Protecting Yourself from Air Pollution
Practical steps to reduce your exposure to air pollution
Read guide →Air Quality for Sensitive Groups
Special considerations for children, elderly, and those with conditions
Read guide →Indoor Air Quality
How to improve the air quality inside your home
Read guide →Air Purifiers: Do They Work?
Science-backed guide to choosing and using air purifiers
Read guide →Seasonal & Regional
How air quality varies by season and location
Wildfire Smoke & Air Quality
Understanding and protecting yourself from wildfire smoke
Read guide →Summer Air Quality Issues
Why air quality often worsens in summer months
Read guide →Winter Air Pollution
Cold weather inversions and winter pollution sources
Read guide →Regional Air Quality Patterns
Why some areas have worse air quality than others
Read guide →City Air Quality Guides
In-depth air quality guides for major US cities
Los Angeles Air Quality
LA smog, pollution sources, neighborhood comparisons, and health tips
Read guide →Phoenix Air Quality
Desert dust, ozone concerns, haboobs, and seasonal patterns
Read guide →Houston Air Quality
Refinery impacts, petrochemical emissions, and health guidance
Read guide →Denver Air Quality
Brown cloud, altitude effects, wildfire smoke, and inversions
Read guide →