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Smoke Ready

While There is Good Fire, There is No Good Smoke

For current Air Quality Indexes for each of our Ranger Districts, please scroll to the bottom of the page.

No matter the benefits of putting or keeping fire on the ground are, they come with a side effect that can be more than a minor inconvenience: Smoke.

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A wildland firefighter uses a drip torch to carry out a prescribed burn
Photo Credit: Benjamin Cossel

For many people, smoke is the most likely way they will experience prescribed fire—and smoke can be linked with a lot of very real trauma. No one likes to breathe smoke, and it can pose real health risks, especially for some people. There is no way to say that any smoke is “good.”

Living in a fire-prone or fire-adapted environment means that smoke is pretty much inevitable, but here's what else we know:

  • Smoke can either be chance or choice and choice is usually less impactful.  Small fires can help prevent larger ones. And smaller smoke events, like those from prescribed fires, can help reduce smoke from big wildfires.
  • In planning a prescribed fire, managers consider potential smoke impacts and plan to burn when they know the smoke will disperse most quickly. Smoke from prescribed fire is generally present for a shorter time and can have less impact, depending on the severity of the burn and fuel loading in the unit. And because prescribed fire is planned residents can be warned ahead of time when smoke might be an issue.
  • Wildfires tend to last longer, sometimes blanketing huge swaths of the state in thick, choking smoke for months at a time.

Smoke and Health

No matter where it comes from, smoke can be a health risk. There are two different types of smoke we see locally from fires in our forests: wildfire smoke and prescribed fire smoke. Both can affect our communities and contain small particles that can cause heart and lung problems although they carry different health risks.

What is in Wildfire Smoke

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a graphic showing particulate matter in smoke

Wildfire smoke is a complex mixture of gases, particles, and water vapor that comes from burning fuels like trees, vegetation, and sometimes building materials1. Some of the components of wildfire smoke are: carbon monoxide, ozone, Sulphur dioxide, nitrogen dioxide, volatile organic compounds, hazardous air pollutants (e.g., polycyclic aromatic hydrocarbons), fine particulate matter. (PM 2.5)

 

  • The majority of air pollution contained in wildfire smoke is from fine particles of matter. These are also referred to as PM 2.5. Because they are so small, PM 2.5 can travel deeply into the lungs and be absorbed into the body, causing health problems.
  • Larger particles are also present in smoke. These are called PM10, and can cause irritation. However, PM 10 are trapped in the lungs and can usually be coughed out.
  • Smoke from burning structures – such as homes, cars, and gas stations – contains harmful gases and toxic chemicals as well as fine particles.
  • Prescribed fire also omits PM 2.5 smoke, but is normally much smaller amounts for smaller amounts of time.
  • Want to do a deeper dive? Check out the EPA's Why Wildfire Smoke is a Health Concern

Who might be at risk of health problems from smoke?

Certain life stages and populations may be at greater risk of experiencing a health effect due to wildfire smoke and may experience more severe effects. These groups are referred to as at-risk populations. The Air Quality Index uses the term “sensitive groups.” Key risk factors that shape whether a population or individual is at greater risk of health effects from wildfire smoke have been identified primarily from epidemiologic studies examining exposure to fine particle pollution in urban settings.

What can I do to protect my health when it is smoky?

What is the U.S. Air Quality Index (AQI)?

The U.S. AQI is EPA’s index for reporting air quality.

How does the AQI work?

The U.S. Air Quality Index (AQI) is EPA's tool for communicating about outdoor air quality and health. The AQI includes six color-coded categories, each corresponding to a range of index values. The higher the AQI value, the greater the level of air pollution and the greater the health concern. For example, an AQI value of 50 or below represents good air quality, while an AQI value over 300 represents hazardous air quality.

For each pollutant an AQI value of 100 generally corresponds to an ambient air concentration that equals the level of the short-term national ambient air quality standard for protection of public health. AQI values at or below 100 are generally thought of as satisfactory. When AQI values are above 100, air quality is unhealthy: at first for certain sensitive groups of people, then for everyone as AQI values get higher.

The AQI is divided into six categories. Each category corresponds to a different level of health concern. Each category also has a specific color. The color makes it easy for people to quickly determine whether air quality is reaching unhealthy levels in their communities. To view the full color table, please visit the EPA's Air Quality page.

Last updated March 14th, 2025

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