Skip to main content

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.”

6MFS Suggestion Form


Have an idea or feedback?

Share it with the NWCG 6MFS Subcommittee
 


Follow NWCG on X and Facebook
 


 

Share on Social Media

Last Modified / Reviewed:

NWCG Latest Announcements

2026 Updates to the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

Date: January 23, 2026
Questions? 
Please contact: Incident and Position Standards Committee

The Incident and Position Standards Committee has updated the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

These updates address changes to incident position names and requirements for qualification, training, and experience. Updates related to the implementation of Complex Incident Management (CIM) and Incident Performance Training Modernization (IPTM) are also included.

The NWCG Wildland Fire Position Qualification Flowchart, PMS 308 has also been updated to reflect the recent changes.

References:

NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

NWCG Wildland Fire Position Qualification Flowchart, PMS 308

IPSC Memo 26-01: January 2026 Updates to the NWCG Standards for Wildland Fire Positions Qualifications, PMS 310-1

Incident Business Committee Memo 26-01: Updated Emergency Equipment Shift Ticket, OF 297

Date: January 22, 2026
Questions? 
Please contact: Incident Business Committee

The Incident Business Committee (IBC) has released Memorandum 26-01: OF 297 and 2026 Fire Use. This memo informs the wildland fire community that the updated Emergency Equipment Shift Ticket, OF 297 is available for download and can be ordered through the Great Basin Cache.

Beginning January 15, 2026 the previous version of the OF 297 form has been discontinued.

For further details, please contact your IBC representative.

References:

Incident Business Committee Memorandum 26-01

Great Basin Cache

NEW! S-390, Introduction to Wildland Fire Behavior Calculations (Blended) Available Now

Date: December 22, 2025
Questions about RT-130? 
Please contact: Fire Behavior Subcommittee

NWCG is excited to announce that the new S-390, Introduction to Wildland Fire Behavior Calculations (Blended) training is now available on the Wildland Fire Learning Portal.

This third course in the series combines online and instructor-led training components aimed at individuals who are involved in planning, managing, and executing wildland fire and prescribed burn operations; who require a thorough understanding of fire behavior calculations to enhance effectiveness and safety. This includes students who require the knowledge and skill necessary to perform the duties of a Type 3 Incident Commander (ICT3), Division/Group Supervisor (DIVS), or Prescribed Fire Burn Boss Type 2 (RXB2).

Students are required to be qualified as any Single Resource Boss position and complete the prerequisite S-290, Intermediate Wildland Fire behavior (Blended) course, before enrolling in S-390.

References:

S-390, Introduction to Wildland Fire Behavior Calculations (Blended)

Wildland Fire Learning Portal

NEW! S-320, Introduction to Incident Management Teams (Blended) Available Now

Date: December 18, 2025
Questions about RT-130? 
Please contact: Incident and Position Standards Committee

NWCG is excited to announce that S-320, Introduction to Incident Management Teams (Blended) is now available on the Wildland Fire Learning Portal!

This blended course combines online learning with instructor-led training, designed for individuals seeking to build leadership skills and gain experience in incident management.

Students are required to complete the prerequisite trainings ICS-100, Introduction to Incident Command System (ICS), ICS-200, Basic ICS for Initial Response, and ICS-700, An Introduction to the National Incident Management System (NIMS) prior to attending S-320.

References:

S-320, Introduction to Incident Management Teams (Blended)

Wildland Fire Learning Portal