Live Air Quality Datafrom

Live Air Quality Index (AQI) data using pm2.5 measurements available in Chiang Mai and Northern Thailand. Note that EPA recommendations are for 24-hour average exposures.

What do these numbers mean?
Category AQI value Actions to Protect your Health
Good 0-50 All groups may participate in normal activities
Moderate 51-100 Unusually sensitive people may experience health effects and may consider limiting activity
Unhealthy for Sensitive Groups 101-150 Children, active individuals, elderly adults and those with heart or lung conditions should limit activity or exertion
Unhealthy 151-200 Individuals in sensitive groups should avoid activity or exertion; all others should limit activity or exertion
Very Unhealthy 201-300 All individuals should avoid activity or exertion
Hazardous 301-500 Health effects are forecast regardless of exertion level; emergency actions are required

Latest view of Chiang Mai

Help us document this year's smoke season

Upload your photos of air pollution, agricultural burning, trash burning and forest fires


Tracking the 2018 Smoke Season

Find out how this year's smoke season is evolving. The data below show daily 24-hour average Air Quality Index (AQI) derived from PM2.5 measurements in Chiang Mai.

Last 7 days AQI

24-hour average AQI, PM2.5

24-hour average AQI, PM2.5

Full 2018 Smoke Season

To see a chart of the full smoke season from January 2018, visit this page on a larger screen.

Hover points for daily AQI number.

Take Action

Stop the Smoke Campaign
You can stop the smoke and save lives by purchasing biochar from local farmers

Make A Difference

Learn more

This timelapse taken over a 10 hour period on March 24th shows how the city is smothered in dangerous particulate pollution from burning. Watch how Doi Suthep mountain slowly appears from behind the thick haze as the day progresses.

Seven-year-old Nong Yen from Mae Rim reminds us of how air pollution affects the health and happiness of our youngest citizens

video: Marisa Marchitelli

SMOKE: A Crisis In Northern Thailand

Follow documentary film maker Marisa Marchitelli as she explores the multifaceted problem of Northern Thailand's annual burning season.

Air Quality Index

A guide to air quality and your health.

Outdoor Air Quality

World Health Organization fact sheet.

The Air We Breathe

A Guardian Cities series investigating air pollution around the world.

Testing Pollution Masks

By Beijing doctor Richard Saint Cyr MD

Tested: Home air filters

As tested by an airborne-particle physicist.

DIY Air Filter

If you can't afford an expensive air filter, build one yourself.

Community Action

Join the conversation and connect with the people who are saving lives in the fight against air pollution in Northern Thailand

Get Started

Bright Ideas

Biomass Power: A Sustainable, Long-term Solution to a Critical Portion of the Northern Haze Problem

Dr. D. Michael Shafer, Director, Warm Heart Foundation

Every year, North Thailand is blanketed by a smothering pall of deadly smoke that kills 3,500 people, hospitalizes another 17,000, and costs Thailand billions of dollars. A significant portion of this smoke comes from burning corn and rice crop residues. If the burning of corn and rice waste alone can be stopped, it will have a major impact on climate change, public health, as well as environmental and poverty reduction efforts.

Eliminating half the smoke from these two sources will remove 34,600 metric tons of the most dangerous fine particulate pollution (PM2.5) from the air. Luckily, there is a known, tested, sustainable solution ready and waiting to eliminate this smoke: the biomass gasifier power plant. read more