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Safety Zone Research

 

Please watch the video for this subject.

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.

 

Category
Operational Engagement
References
RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR)
Wildland Fire Lessons Learned Center
Wildland Fire Leadership Development Program
Incident Response Pocket Guide (IRPG), PMS 461


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Updated NWCG Standards for Course Delivery, PMS 901-1 and NWCG Training Course Completion Certificate, PMS 921-1

Date: July 17, 2024
Contact: Training Delivery Committee 

The Training Delivery Committee (TDC) has updated the NWCG Standards for Course Delivery, PMS 901-1 to reflect changes in the standards for course management and delivery. These changes have been reviewed and approved by the members of TDC over the past year. Significant updates include additional delivery methods, updated definitions, and instructions for the use of digital signatures on training certificates. The NWCG Training Course Completion Certificate, PMS 921-1 has been updated to lock after an electronic signature has been applied.

References:

NWCG Standards for Course Delivery, PMS 901-1

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IBC Memo 24-01: OF 297 Signature Order and 2024 Fire Season Use IBC Memo 24-02: Summary of Changes for SIIBM, PMS 902

Date: July 15, 2024
Contact: Incident Business Committee 

The NWCG Incident Business Committee (IBC) has recently released two memorandums. The first provides direction on the use of the Emergency Equipment Shift Ticket, OF 297 for the 2024 fire season. Due to delays in hard copy printing, both the 2024 revision and the older version of the Emergency Equipment Shift Ticket, OF 297 are acceptable for use during the 2024 fire season.

The second memorandum documents the updates of the newly revised NWCG Standards for Interagency Incident Business Management (SIIBM), PMS 902. The summary of changes attached to the memo covers the major updates and process changes from the 2022 version.

References:

IBC Memorandum 24-01: OF 297 Signature Order and 2024 Fire Season Use

IBC Memorandum 24-02: Summary of Changes for the NWCG Standards of Interagency Incident Business Management, PMS 902

IBC Memorandum 24-02 Attachment: Summary of Changes

NWCG Standards for Rapid Extraction Module Support, PMS 552

Date: July 10, 2024
Contact: Incident Medical Unit Subcommittee 

A new publication from the Incident Medical Unit Subcommittee is now available. The NWCG Standards for Rapid Extraction Module Support, PMS 552 will be used as a guide and as an opportunity to begin to build out Rapid Extraction Module Support (REMS) modules for the remainder of Fire Year 2024. These standards will be fully implemented as the minimum standard starting in January 2025.

NWCG Standards for Rapid Extraction Module Support outlines the roles, duties, qualifications, and equipment pertinent to REMS. A REMS team, strategically stationed at wildland fires, plays a pivotal role in prioritizing swift access and medical treatment to injured or ill firefighters for safe and efficient egress off the fireline. This ensures their rapid transport to definitive medical care in cases of emergency during firefighting operations, highlighting the invaluable contribution of the REMS team to firefighter safety and well-being.

References:

NWCG Standards for Rapid Extraction Module Support, PMS 552

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Date: July 2, 2024
Contact: National Interagency Fire Center 

The National Wildfire Coordinating Group (NWCG) would like to recognize July 2, 2024, as National Wildland Firefighter Day (NWFFD). Established in 2022, NWFFD honors the dedication of wildland firefighters and support personnel. This day falls within the 2024 Week of Remembrance (June 30 - July 6), providing an opportunity to renew our commitment to wildland firefighter safety while remembering those who have fallen in the line of duty.

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