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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

Incident Position Standards and the Next Generation Position Task Books Now Available for RADO and INCM

Date: July 30, 2025
Questions?  Please contact:
Incident Logistics Subcommittee
 

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Radio Operator (RADO) and Incident Communications Center Manager (INCM).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

NWCG Radio Operator Position Page

NWCG Incident Communications Center Manager Position Page

ETC Equipment Bulletin: 25-004 NEW Aquatic Invasive Species – Golden Mussels

Date: July 29, 2025
Questions?  Please contact:
Equipment Technology Committee
 

The Equipment Technology Committee (ETC) issued Equipment Bulletin: 25-004, notifying the wildland fire community about a newly discovered invasive species and actions to take if found. Golden mussels, a highly invasive species recently identified in California, pose a significant risk to native ecosystems, infrastructure, and fire equipment. These 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 and location details.

Read the complete ETC Equipment Bulletin: 25-004 to learn more. 

References:

NWCG Alerts

ETC Equipment Bulletin: 25-004

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

Incident Position Standards and the Next Generation Position Task Books Now Available for ICT5 and FFT1

Date: July 29, 2025
Questions?  Please contact:
Incident Command Subcommittee
Incident Operations Subcommittee

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Incident Commander Type 5 (ICT5) and Firefighter Type 1 Squad Boss (FFT1).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

NWCG Incident Commander Type 5 Position Page

NWCG Firefighter Type 1 Squad Boss Position Page

Incident Position Standards and the Next Generation Position Task Books Now Available for ATBM and FWBM

Date: July 28, 2025
Questions?  Please contact:
Airtanker Base Operations Unit

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Airtanker Base Manager (ATBM) and Fixed Wing Base Manager (FWBM).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

NWCG Airtanker Base Manager Position Page

NWCG Fixed Wing Base Manager Position Page