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Safety Zone Research

Please watch the video below for this subject:

WFSTAR: Latest Research on Estimating Safety Zones (Time 6:15)


First, a Fire Behavior 101 refresher:  You can warm yourself around the sides of a campfire for quite some time; that’s radiant heat. If you hold your hands over the top of the fire, you’ll get burned relatively quickly; that’s convective heat.

Basically, wind or slope can tip the flames over, so that the convective heat is no longer going straight up, but is now aimed more along the ground, sending the heat and hot gasses much further ahead. This causes preheating of the fuels, faster fire spread, and greater fire intensities. You’ll need a larger safety zone if that fire is coming towards you.

The current equation for safety zone size on the Safety Zones page of the Incident Response Pocket Guide (IRPG), PMS 461:

4 x Flame Height = Safe Separation Distance

To make estimations of flame height though, you either have to use past fire behavior observations or use your experience to guess what the fire may do in the future. After a decade of research, Bret Butler, at the Missoula Technology and Development Center, suggests removing the uncertainty and guesswork that comes with estimating flame height by taking the general rule of thumb:

Flame Height = 2 x Vegetation Height

…and substituting that Flame Height equation into the original IRPG equation, to give:

4 x 2 x Vegetation Height = Safe Separation Distance, which simplified is:
 8 x Vegetation Height = Safe Separation Distance

But remember, that’s still for radiant heat only, on flat ground, with no wind. To take into account the convective heat from slope or wind, Butler’s research suggests that a Slope Wind Factor is needed in the equation:

8 x Vegetation Height x Slope Wind Factor = Safe Separation Distance

But what is the Slope Wind Factor? Current research is indicating that the Slope Wind Factor is between 1 and 10, with Butler arguing it may be closer to between 1 and 5. Butler’s ongoing research is focused on answering that question by gathering sensor data on fires, running computer simulations, and refining the models.

In the meantime, utilize the calculations in the Safety Zones page of your IRPG to help you determine a bare minimum size for your safety zone with the understanding that slope and wind need to be considered in your decision-making.

But remember, a safety zone is only good if you can get there.

References:

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Operational Engagement

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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 

Coming Soon! Ransom Road WFSTAR Module

Date: December 9, 2025
Questions about RT-130? 
Please contact: NWCG Audiovisual Specialist

On June 8, 1981, the Ransom Road Fire swept across Merritt Island National Wildlife Refuge in Florida, marking a defining moment in wildland fire management. This event led directly to the creation of the U.S. Fish and Wildlife Service's professional fire program.

Later this month, NWCG will release a compelling video that brings the Ransom Road Fire to life through firsthand accounts, official reports, and animated maps. Rob Lee, second on site during the deployment, shares his powerful recollections of that day. 

This video will be going live later this month in NWCG's RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR) Catalogue.

References:

WFSTAR Catalogue 

Wildland Fire Lessons Learned Center

2025-2026 Wildland Fire Leadership Campaign: "Leadership Levels" Now Available

Date: October 15, 2025
Questions? Please contact:
Leadership Committee

NWCG is excited to announce the release of the Leadership Committee’s 2025–2026 Leadership Campaign, themed “Leadership Levels.” 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.

The campaign is structured into four quarters and may be completed at any time between October 1, 2025 -December 31, 2026. Leadership levels will be released quarterly.

Quarter One materials are now available on the Wildland Fire Leadership Development Program website and focus on Leadership Level 1, Follower (Self-Leadership).

References:

2025/2026 NWCG Leadership Campaign - Leadership Levels

Wildland Fire Leadership Development Program

Leadership Committee

Updated! L-280, Followership to Leadership (Instructor-led) Course

Date: October 3, 2024
Questions? Please contact:
Leadership Committee

NWCG is pleased to announce the updated L-280, Followership to Leadership (Instructor-led) course is now available. L-280 is intended for operational personnel at the Firefighter Type 1 level, and for individuals pursuing Leadership Level 2, New Leader. 

This instructor-led course is a primer on leadership and the second formal course in the Wildland Fire Leadership Development Program. It helps emerging leaders build the confidence, skills, and mindset needed to lead effectively in high-risk environments. 

For more information about leadership development and available courses, visit the Leadership Committee Web Portal.

References:

L-280, Followership to Leadership (Instructor-led)

Wildland Fire Leadership Development Program

Wildland Fire Learning Portal