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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.

References:

Category
Firefighter Health and First Aid

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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

New! Ransom Road WFSTAR Module

Date: December 16, 2025
Questions about RT-130? 
Please contact: NWCG Audiovisual Specialist

NWCG is excited to announce the release of the new Ransom Road Fire Module to RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR).

This module features a firsthand account from Rob Lee, official reports, and animated maps of the Ransom Road Fire which occurred on June 8, 1981, in Florida's Merritt Island National Wildlife Refuge.

The module is available now in NWCG's RT-130, WFSTAR Catalog.

References:

WFSTAR Catalog

Wildland Fire Lessons Learned Center

Call for Nominations: Paul Gleason Lead by Example Award

Date: December 11, 2025
Questions? Please contact:
 Leadership Committee 

Do you know someone working in wildland fire who strives to make positive change and is undeterred by obstacles or setbacks? Now is your chance to give that person the acknowledgment they deserve by nominating them for a Paul Gleason Lead by Example Award.

This award, is presented by the NWCG Leadership Committee to remember Paul Gleason's contributions to the wildland fire community and to recognize individuals or groups that exhibit the same spirit and dedication to leadership – those who lead by example.

Nominations can be submitted via email with an attached Lead by Example Form to BLM_FA_Leadership_Feedback@blm.gov or through the online form. 

Tips for successful nominations and more information can be found on the Lead by Example webpage. All nominations must be submitted by December 31, 2025.

References:

Paul Gleason Lead By Example Award 

Paul Gleason Lead by Example Award Nomination Form 2025 

Leadership Committee