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Week of Remembrance

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2015 WOR: New Research on Safety Zones

Ribbon symbol for WOR next to Wildland Fire Lessons Learned logo.Week of Remembrance June 30-July 6, 2015

 

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 pre heating 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 in the NWCG Incident Response Pocket Guide (IRPG), PMS 461 (page 8) is:

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…Stay tuned.

In the meantime, utilize the calculations on page 8 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…join us tomorrow for some thoughts on Escape Routes.

The “Take 5@2” safety messages are a cooperative project of 6 Minutes for Safety, the Wildland Fire Safety Training Annual Refresher (WFSTAR), NIFC External Affairs, the NWCG Leadership Committee, the NWCG Risk Management Committee, and the Wildland Fire Lessons Learned Center.

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NWCG Latest Announcements

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
Questions? 
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
Questions? 
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
Questions? 
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