This year’s “State of the Air” report makes it clear that climate change is worsening our air quality and putting more people's health at risk. As we enter Wildfire Awareness Month, we take a closer look at the dangerous trend toward more frequent and intense spikes in particle pollution levels due to wildfires and what can be done to protect people’s health.

A Worrisome Trend

most days with worst levels of daily particle pollution Figure 1. Most Ever Days with Worst Levels of Daily Particle Pollution

Wildfires are becoming more frequent and severe due to our changing climate. Science has proven that particle pollution, one of the main components of wildfire smoke, is harmful to the health of everyone, especially children, older adults, people who are pregnant and people with lung or cardiovascular disease. Exposure to even low levels of fine particles can be deadly. And even people far away from a wildfire can be exposed to smoke, which can travel thousands of miles.

Air Quality Index graph

Each year, the “State of the Air,” provides a "report card" on air pollution levels across the nation. This year’s report found an alarming trend: wildfire-driven particle pollution is getting worse, and an unprecedented number of people were impacted by spikes in daily levels of particle pollution. 

Most people have heard of “code orange” and “code red” days for air quality, meaning that air pollution levels are high on these days according to the U.S. Environmental Protection Agency’s (EPA) Air Quality Index (shown to the right). But not many people have heard of “code purple” or “code maroon” days. Purple (or “very unhealthy”) and maroon (or “hazardous”) are the levels on the Air Quality Index that carry the strongest health warnings and mean the air quality on those days is a serious health threat to everyone living in those areas. On purple days, “the risk of health effects is increased for everyone.” On maroon days, the highest category, a health warning of emergency conditions is issued, saying, “Everyone is more likely to be affected.”

This year’s “State of the Air” report (which looked at air quality data from 2020, 2021 and 2022), found that over 32 million people in 58 counties across 10 states experienced “purple” or “maroon” days for daily particle pollution. This is a significant increase from previous years, and unlike anything we have seen in the history of the report. This trend is expected to continue as climate change worsens.

Wildfires in the western United States and Canada remain the major contributing factor to the increasing number of days and places with unhealthy levels of particle pollution in recent years. The wildfires are also increasing the severity of pollution levels people are exposed to, resulting in the sharp increase seen in the number of days that are either purple or maroon on the Air Quality Index. For the first time, all the 25 worst cities for short-term particle pollution were in the Western U.S. But as we saw last summer from the devastating fires in Hawaii and when smoke from wildfires in Canada affected millions along the East Coast and Midwest, wildfire smoke impacts people across the country – not just in the areas close to wildfires.

How Did We Get Here?

Climate change is creating drier, hotter conditions that are fueling more catastrophic wildfires. Over the last few decades, the Clean Air Act has made tremendous progress in cleaning our air and has saved millions of lives, with controls placed on industry, power plants and the transportation sector that have significantly reduced harmful emissions, including particle pollution. But wildfires are now threatening to reverse that progress.

Additionally, historical fire suppression policies in the United States have led to a dangerous buildup of "fuels” such as dead plants, grasses, leaf litter, sticks and trees. Prescribed fire, which is the careful burning of areas vulnerable to wildfire under safe, controlled conditions, can prevent that type of dangerous buildup that could potentially lead to a catastrophic fire. Prescribed fire is an important tool that can reduce wildfire risk and lower the health and air quality impacts associated with catastrophic wildfire. When properly planned, prescribed fires are implemented under predictable conditions where additional measures can be taken to minimize smoke exposures, including favorable weather conditions and wind patterns that will allow smoke to move away from sensitive areas (e.g., populated areas, hospitals, schools, roadways), in accordance with local and national air quality standards.

For more information, see our research review, “Can Prescribed Fires Mitigate Health Harm?”

Tips to Protect Your Health from Wildfire Smoke

Wildfires are now affecting people in areas that have never experienced wildfire smoke. We’ve heard from many who felt unprepared to protect themselves. Here are some tips on how to help stay safe and protect your lungs from wildfire smoke. 

  1. Check the air quality index. Check the Air Quality Index available at to stay informed about harmful air pollution in your area. The color-coded forecasts let you know when the air is unhealthy in your community. 
  2. When appropriate and possible, stay indoors and protect the air in your home. When a wildfire happens, stay indoors as much as possible, if you can keep the windows and doors closed and dampers shut. Tuck damp towels along the bottom of doors and windows to block outdoor air. Create and use a “clean room” (more info here) with the air filter running. Run your air conditioner on “recirculate.” Air cleaning devices that have HEPA filters can provide added protection from the soot and smoke. Seek shelter elsewhere if you do not have air conditioning and it is too hot to stay inside with the windows closed. 
  3. Protect the air in your vehicle. When traveling in a vehicle, keep windows closed, run the air conditioner and set air to recirculate to reduce smoke.
  4. If you must go outside, wear proper protection. Respirator masks that are rated as N95 or higher help reduce inhalation of particle pollution. These masks must fit securely to work. They do not work for children or people with beards and can be difficult to wear for people with chronic lung diseases. 
  5. Talk to your doctor. Talk with your doctor about how to prepare for smoke, especially if you or someone in the family fits into one of these categories: works outdoors; is under the age of 18 or over the age of 65; is pregnant; or has asthma, COPD or other lung diseases, cardiovascular diseases, or diabetes.
  6. Get prepared. Before a wildfire occurs, preparation is key, especially if you live where wildfire risk is high. Some steps you can take include: have a disaster preparedness plan and emergency kit, sign up to receive local emergency alerts, create a clean room in your home, make sure you have enough medications on hand, and check in with your doctor. 

For additional tips, fact sheets, videos and other resources, visit

From individuals to federal lawmakers, everyone can play a part in cleaning up air pollution and addressing climate change. See our “State of the Air 2024” Recommendations for Action to learn more about what action is needed to protect public health and clean up the air.

Freedom From Smoking Clinic
, | May 29, 2024
Freedom From Smoking Clinic
Detroit, MI | May 29, 2024