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Effects of Smoke Exposure

 

Wildland fire 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 can pose a health risk particularly with higher exposures or long duration exposures. Wildland fire smoke can cause irritating respiratory symptoms and, over time, could possibly increase the risk of developing long-term illnesses.

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

  • Carbon Monoxide (CO) – Exposure to CO from wildland fire smoke or from other sources (such as exhaust from chainsaws, engines, or pumps) may lead to a variety of symptoms including impaired vision and judgement, headaches, and fatigue. In extreme situations, high levels of exposure can cause asphyxiation, which can lead to death.
  • Fine Particulate Matter (PM) – Wildland fire smoke contains very small particles (PM) which can penetrate deep into the lungs. Long-term exposure can affect the lungs and heart, especially in individuals with underlying health issues (e.g., high blood pressure, high cholesterol), smokers, and those who work in stressful environments.
  • A variety of other chemicals, such as polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs), are also present in wildland fire smoke. These may further increase your risk of short-term or even long-term health effects.
  • COVID-19 –  Susceptibility to COVID-19 resulting from smoke exposure has not yet been specifically studied, but related studies show exposure to wildland smoke can lead to an increased susceptibility to respiratory infections, including pneumonia and bronchitis. Additionally, severity of infections or symptoms may be increased due to the respiratory tract’s immune responses to smoke exposure. Thus, it’s assumed that risk of COVID-19 infection would be high for firefighters with respiratory issues resulting from wildland smoke exposure.

Smoke is part of the wildland fire environment. Now more than ever, firefighters and incident overhead should be on the lookout for opportunities to reduce exposure. 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? Other considerations include:

  • Is camp located where smoke accumulates?
  • Is the crew dispersed holding a smoke-choked road when the probability of ignition is near zero?
  • Are firefighters mopping-up an area that poses no operational threat?

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

  • Mop-up
  • Holding
  • Line construction
  • Firing

Think about and discuss this partial quote from an article in Two More Chains: Summer 2017 Low Hanging Fruit:

“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.”

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NWCG Latest Announcements

NWCG Committees Observe Suicide Prevention Awareness Week: September 7-13, 2026

Date:  September 8, 2026
Questions? 
Please contact: Health and Wellness Subcommittee

The NWCG Health and Wellness Subcommittee (HWSC) and Safety/Risk Management Committee (SRC) recognize the unique challenges and demands faced by the wildland fire community. The HWSC and SRC know that we are all stronger together and believe in fostering a culture of support, understanding, and resilience.

Suicide Prevention Awareness encourages us to actively connect with and support each other. For more information that could make a difference for yourself or someone else please review the materials and resources provided for the 2026 Suicide Prevention Awareness Week.

References:

2026 Letter from Leadership

988 Suicide & Crisis Lifeline

Health and Wellness Subcommittee

Safety and Risk Management Committee

2025 Paul Gleason Award Winners Announced

Date:  August 13, 2026
Questions? 
Please contact: Leadership Development Subcommittee

The NWCG Qualifications Management Committee (QMC) and Leadership Development Subcommittee (LDSC) are proud to announce the recipients of the 2025 Paul Gleason "Lead By Example" awards. Award categories include Initiative and Innovation, Mentoring and Teamwork, and Motivation and Vision.

Congratulations to the awardees:

  • Hunter Bell, U.S. Forest Service — Initiative and Innovation
  • Shannon Deane, U.S. Wildland Fire Service— Initiative and Innovation
  • Chris Delaney, U.S. Wildland Fire Service — Motivation and Vision
  • Sean Peterson, U.S. Forest Service — Mentoring and Teamwork

References:

Paul Gleason Lead By Example Award

Wildland Fire Leadership Development Program (WFLDP)

Leadership Development Subcommittee

LMC Equipment Bulletin 26-001: Aquatic Invasive Species – Seasonal Reminder for Mussels

Date:  July 30, 2026
Questions? 
Please contact: Equipment and Technology Subcommittee

The Logistics and Equipment Management Committee (LMC) issued Equipment Bulletin 26-001: Aquatic Invasive Species - Seasonal Reminder for Mussels, reminding the wildland fire community that aquatic mussels continue to be a problem. Mussels rapidly colonize hard and soft surfaces, including aquatic plants and fire equipment, clogging pipes, fouling motors, disrupting water systems, and impacting native species.

To help prevent their spread, fire personnel must follow the decontamination procedures outlined in the NWCG Guide to Preventing Aquatic Invasive Species Transport by Wildland Fire Operations, PMS 444. Additionally, report any sightings immediately to your Lead Resource Advisor and include clear, close-up photos (with a pen or your hand for size reference) and location details.”

Read the complete LMC Equipment Bulletin 26-001, to learn more. 

References:

NWCG Alerts

LMC Equipment Bulletin 26-001: Aquatic Invasive Species - Seasonal Reminder for Mussels

NWCG Guide to Preventing Aquatic Invasive Species Transport by Wildland Fire Operations, PMS 444

Intermediate Faller (FAL2) Position Task Book Update

Date:  July 24, 2026
Questions? 
Please contact: Tree Felling Subcommittee

NWCG Operations Management Committee (OMC) has issued an update to the NWCG Position Task Book for Intermediate Faller (FAL2), PMS 311-91. To ensure clarity for both trainees and evaluators, the updated FAL2 Position Task Book (PTB) explicitly states who is authorized to sign off on your tasks:

“Evaluators must be qualified as a FAL2, or an Advanced Faller (FAL1).”

If you are currently working out of a previously published version of the FAL2 PTB, you do not need to restart. However, OMC highly encourages you to take the following step to prevent any confusion in the field:

  • Print and replace the updated evaluator information page (page 2) in your current physical PTB.

References:

Intermediate Faller (FAL2) Position Page

RMC Memo 26-01: Transition Plan for Implementing Updates to Intermediate Faller (FAL2) Position Qualifications

NWCG Position Task Book for Intermediate Faller (FAL2), PMS 311-91