Effects of Smoke Exposure

Firefighter Health First-Aid
Page Last Modified / Reviewed: 
Sep 2019


First and foremost, exposure to wildfire smoke may limit your ability to work efficiently and effectively. Wildfire smoke is a complex mix of chemicals and particles, which varies depending on the fuels, soil, weather, fire intensity, and the burning phase of the fire. Some of the chemicals and particles that are present in wildfire smoke can pose a health risk. These health risks increase with higher exposures or longer duration of exposures. Whether on prescribed fires or wildfires, your exposure to wildfire smoke could cause irritating respiratory symptoms and, over time, could possibly increase your risk of developing long-term illnesses. However, further research is needed to better understand the long-term health risks.

While the makeup of smoke varies, here are just a few of the things in smoke that could impact your health:

  • Carbon Monoxide (CO) - Exposure to CO from wildfire smoke, or from other sources such as exhaust (from chainsaws, engines, or pumps) may lead to a variety of symptoms: impaired vision and judgment, headaches, fatigue, and with high levels of exposure, asphyxiation, which in extreme situations can even lead to death.
  • Fine Particulate Matter (PM) – Wildfire smoke contains gases, vapors, and very small particles or PM. PM have the ability to penetrate deep into your lungs and some may even get into your bloodstream. Studies of PM in ambient air pollution have shown that repeated or continuous exposure can negatively affect a person’s lungs and heart. This is especially true for people with underlying health issues (e.g. high blood pressure, high cholesterol), smokers, and people who work in stressful environments.
  • A variety of other chemicals are also present in wildfire smoke, such as polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Additional harmful chemicals can be released when synthetic materials burns, such as those found in wildland urban interface (WUI). These exposures may further increase your risk of experiencing short-term or even long-term health effects.

There is no easy way to avoid exposure to smoke; it is part of the wildland fire environment. Firefighters and incident overhead personnel should be on the lookout for opportunities to reduce their exposures. Incident overhead can think strategically about assigning wildland firefighting tasks in certain work environments and ask, “Does our workforce really need to be in the smoke to meet the operational objectives?” Some other things to consider include:

  • Is camp placed in a valley where smoke accumulates?
  • Is the crew strung out “holding” a smoke-choked road when the probability of ignition is near zero?
  • Are firefighters mopping-up stuff that poses no operational threat?

Discussion: There are certain tasks that have been associated with higher exposures to potentially harmful chemicals. Below are some of those tasks. How can you/your crew realistically reduce smoke and PM exposure during these tasks:

  • Mopup
  • Line Construction
  • Holding
  • Firing

Think about and discuss this partial quote from an article from the Summer 2017 Two More Chains

“As CO exposure increases, your ability to think clearly decreases.   Being in smoke you don’t need to be in is the epitome of not working “smarter.” In fact, it is actually working dumber.”

Additional Resources

Incident Management Situation Report (IMSR)
Incident Response Pocket Guide (IRPG), PMS 461
NWCG Standards for Helicopter Operations, PMS 510
RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR)
Interagency Standards for Fire and Fire Aviation Operations (Red Book)
Wildland Fire Lessons Learned Center

Have an idea? Have feedback? Share it.

EMAIL | Facebook | URL: https://www.nwcg.gov/committees/6-Minutes-for-safety
MAIL: 6 Minutes for Safety Subcommittee • 3833 S. Development Ave • Boise, ID 83705 | FAX: 208-387-5378