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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

2025 Wildland Fire EMS Awards

Date:  June 12, 2026
Questions? 
Please contact: Emergency Medical Committee

The NWCG Emergency Medical Committee (EMC) announces the recipients of the 2025 Wildland Fire Emergency Medical Service (EMS) Awards. EMC annually recognizes individuals and groups who have demonstrated outstanding actions or accomplishments that are above and beyond the expectation of one’s normal mission or job duties.

Congratulations to all the awardees and nominees. Through leadership and initiative, they have made significant contributions to the safety of the wildland fire community. These awards are well deserved.

References:

2025 Wildland Fire EMS Awards

Emergency Medical Committee

Incident Position Standards and the Next Generation Position Task Book Now Available for RAMP

Date:  June 12, 2026
Questions? 
Please contact: Airtanker Base Operations Unit

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Book are now available for Ramp Manager (RAMP).

The Performance Support Package for this position was 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 release in January 2027.

References:

NWCG Ramp Manager Position Page

National Interagency Aviation Committee

Make an Impact: Serve the Wildland Fire Community as an IPTM SME!

Date:  June 11, 2026
Questions? 
Please contact: NWCG SME Specialist

Note: Positions with an * will last approximately 6 months.
Positions with ** will last 12 - 18 months.

NWCG is seeking experienced wildland firefighters and support personnel to serve as Subject Matter Experts (SMEs) for the Incident Performance and Training Modernization (IPTM) initiative. IPTM aims to transition NWCG’s training and qualification system to a performance-based model by updating position descriptions, Incident Position Standards, Next Generation Position Task Books (Next Gen PTBs), and training where needed.

NWCG is currently recruiting SMEs for the Fall 2026 positions listed below:

  • Equipment Manager (EQPM)*
  • Fixed Wing Parking Tender (FWPT)**
  • Mixmaster (MXMS)*
  • Public Information Officer Complex (PIOC)*
  • Retardant Crewmember (RTCM)*
  • Strike Team Leader Crew (STCR)*
  • Strike Team Leader Engine (STEN)*
  • Strike Team Leader Heavy Equipment (STEQ)*
  • Task Force Leader (TFLD)**
  • Wildland Fire Investigator (INVF)** 

Projects begin October 2026. Sign up by July 10, 2026, at the link below and review the attached document for additional details. 

References:

NWCG SME Interest Sign-up

IPTM Subject Matter Expert Duties and Expectations Document

Incident Performance and Training Modernization (IPTM)

RMC Safety Bulletin 26-001: Rhabdomyolysis in Wildland Firefighters

Date:  May 28, 2026
Questions? 
Please contact: Risk Management Committee

The Risk Management Committee (RMC) has issued Safety Bulletin 26-001: Rhabdomyolysis in Wildland Firefighters. Research from 2016 to 2025 shows that 88 cases of rhabdomyolysis (rhabdo) were reported. Analysis of reports from eSafety, the Safety Management Information System (SMIS), and the Wildland Fire Lessons Learned Center (LLC) indicates that rhabdo is common during this time of year due to Work Capacity Tests and contributing factors such as weather, hydration, nutrition, and medication or supplement use.

RMC issued this safety bulletin to raise awareness in the Wildland Fire Community, and to provide research findings and educational resources that support reducing future cases of rhabdo.

References:

NWCG Alerts

RMC Safety Bulletin 26-001: Rhabdomyolysis in Wildland Firefighters