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Heat Stress

During activity, the body releases more than 70 percent of the energy used by muscles as heat.  As a result, heat loss is crucial to prevent an excessive rise in body temperature during firefighting activities. If heat exchange between the body and the environment is impaired, such as in hot or humid environments, firefighter performance can be substantially impaired.

A heat-related illness (HRI) is a potentially fatal disorder caused by elevated body temperatures from internal heat produced by activity or external environmental heat added to the body that cannot be removed to maintain normal body temperature.

Symptoms of an HRI may be difficult to recognize and may occur in no particular order. They may include:

  • Muscle cramps and weakness.
  • Dizziness, headache, and irritability.
  • Rapid, weak pulse.
  • Vomiting.
  • Profuse sweating with cool, clammy skin leading to hot, dry skin.
  • Loss of consciousness.

If you suspect a heat illness, stop work and begin treatments to cool down the body, and consider further procedures.

Considerations for mitigation during firefighting activity:

  • Ability to handle heat is different between individuals and varies on a daily basis.
  • Performing physical tasks, such as hiking, or or digging fireline, is our largest producer of body heat.
  • Hiking typically raises your body temperature 1 to 2 degrees Fahrenheit.
  • At elevated body temperatures, the risk of HRI is higher.
  • Maintain low skin temperature when possible, as it allows heat transfer from the body.
  • Pack weights exceeding 25 percent of body weight add to the body’s demands during activity.
  • Recovery of high body temperature requires:
    • Reduction of work output.
    • Removal from sources of heat.
    • Proper nutrition and hydration strategies.

Note: Recovery is not just a shift-to-shift concept. It is also task-to-task and even a minute-to-minute process.

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NEW! S-212, Intermediate Faller (Online) Course Available Now 

Date:  April 23, 2026
Questions? 
Please contact: Hazard Tree and Tree Felling Subcommittee

NWCG is pleased to announce that the new S‑212, Intermediate Faller (Online), course is now available on the Wildland Fire Learning Portal (WFLP). This second course in the series provides students with the knowledge and skills required to perform the duties of an Intermediate Faller (FAL2), as described in the FAL2 Incident Position Description. This course is intended for individuals seeking to advance from Basic Faller (FAL3) to FAL2.

S‑212, Intermediate Faller is a fully online, self‑paced training program consisting of 13 units. Learners will engage with interactive, scenario‑based content designed to progressively build foundational skills and knowledge essential for the FAL2 role.

Students must be qualified as a Basic Faller (FAL3) prior to enrolling in S‑212, Intermediate Faller course.

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 2027.

References:

S-212 Intermediate Faller (Online)

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

Intermediate Faller (FAL2) Position Page

NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212

New Aircraft Flight Schedule Form, PMS 249

Date:  April 17, 2026
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Please contact: National Coordination System Committee

A new publication from the National Coordination System Committee (NCSC) is now available. The NWCG Aircraft Flight Schedule Form, PMS 249, will be used for aviation crews and dispatch to share flight information that is needed for resource tracking, and if needed, for emergency procedures.

For further details, please contact your NCSC representative. 

References:

NCSC Memo 26-01: Implementation of NWCG Aircraft Flight Schedule Form, PMS 249

NWCG Aircraft Flight Schedule Form, PMS 249

New Glossary Term for Review

Date:  April 15, 2026
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Please contact: Data Standards and Terminology Board (DSTB)

The Data Standards and Terminology Board is requesting feedback on a new glossary term: Resource Protection Measure (RPM).

The proposed definition is: Practical guidance provided for incident personnel in a manner in which incident objectives can be achieved while reducing impacts to identified resources across the landscape. RPMs are informed by, but not restricted to, Minimum Impact Strategies and Tactics (MIST).

Please review, share with your subgroups, and provide feedback as appropriate through the following form: Request Feedback The comment period will close May 10, 2026.

Thank you for your engagement in the NWCG glossary process – your participation is key to our success.

References:

Glossary Request Feedback

Quarter Three Materials for the 2025-2026 Wildland Fire Leadership Campaign Now Available

Date:  April 1, 2026
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Please contact: Leadership Committee

NWCG is excited to announce that Quarter Three materials for the 2025/2026 Wildland Fire Leadership Campaign are now available. This annual initiative offers all students of leadership and wildland fire management an opportunity to engage with essential leadership skills and knowledge needed to lead effectively in dynamic environments.

Quarter Three materials focus on Leadership Level 3: Leader of People (Develop Intent). Leadership Level 3 is where your values, your team, and your influence come together. Leaders of People put their teams first, build trust, and lead with authenticity. They mentor future leaders and shape decisions up and down the chain.

References:

2025/2026 NWCG Leadership Campaign - Leadership Levels

Wildland Fire Leadership Development Program

Leadership Committee