🔥 Wildfire season is here — check before you head out
Is the air safe outside?
Real-time air quality and wildfire smoke check for any city. One number, one color, clear advice — no sign-up, free forever.
What the colors mean
The US Air Quality Index (AQI) grades air from 0 to 500 in six color-coded levels.
😊 Good
Air is clean. Great time for outdoor activities and exercise.
🙂 Moderate
Air is acceptable. Outdoor activities are fine for most people.
😐 Unhealthy for Sensitive Groups
General public is OK, but keep outdoor efforts light and take breaks.
😷 Unhealthy
Avoid prolonged outdoor exertion. Wear an N95/KN95 mask outside and run an air purifier indoors.
🚨 Very Unhealthy
Stay indoors with windows closed. Use an air purifier. N95 mask is a must if you have to go out.
☠️ Hazardous
Health emergency. Everyone should stay indoors, seal windows, and run air purifiers continuously.
🔥 Why is wildfire smoke dangerous?
Wildfire smoke is packed with fine particles (PM2.5) small enough to travel deep into your lungs and enter your bloodstream. Even hundreds of kilometers from a fire, smoke can push air quality into unhealthy ranges. Short-term exposure irritates eyes and airways; it's especially risky for children, older adults, pregnant people, and anyone with asthma, heart or lung conditions.
🔬 What is PM2.5?
PM2.5 means particulate matter smaller than 2.5 micrometers — about 1/30 the width of a human hair. It's the main harmful ingredient of wildfire smoke, and also comes from traffic and industry. The WHO recommends keeping 24-hour average exposure below 15 µg/m³. When PM2.5 spikes, an N95/KN95 mask outdoors and a HEPA air purifier indoors make a real difference.
😷 When should I wear a mask?
From AQI 151 (red, “Unhealthy”) upward, everyone benefits from wearing a well-fitted N95/KN95 outdoors. Sensitive groups should consider one from AQI 101 (orange). Cloth and surgical masks do little against fine smoke particles.
🏠 What helps indoors?
Close windows and doors, run an air purifier with a HEPA filter, and avoid adding indoor smoke (candles, frying). If you don't own a purifier, a box fan taped to a furnace filter is a proven budget alternative during smoke events.