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PMS 437

Fire Behavior Field Reference Guide, PMS 437

PMS 437 Cover. Decorative.
The Fire Behavior Field Reference Guide is intended to be used in conjunction with the NWCG Guide to Fire Behavior Assessment, PMS 437-1.

The Fire Behavior Field Reference Guide contains helpful references to the factors from the fire triangle (fuels, weather, and topography), including features that are vital to field-going fire managers. It provides detail about the fire behavior models and tools used to estimate fire ignition, spread/size, fireline intensity, and crown fire potential. The reference material will assist with decision support using various tools and methodologies.

The guide will be updated twice annually (April and November) as necessary to reflect the most recent science and technologies for field use to help improve and assist with decision support, fireline safety, and fire behavior interpretation. As new and improved safety zone research is obtained and available for distribution, the Fire Behavior Field Reference Guide will be updated to house that information. YouTube videos will be uploaded periodically to provide additional supporting documentation:
www.youtube.com/user/FireBehaviorSC.

The Fire Behavior Field Reference Guide is developed and maintained by the Fire Behavior Subcommittee (FBSC), under the direction of the Fire Environment Committee (FENC), an entity of the National Wildfire Coordinating Group (NWCG).

While they may still contain current or useful information, previous editions are obsolete. The user of this information is responsible for confirming that they have the most up-to-date version. NWCG is the sole source for the publication.
Comments, questions, and recommendations shall be submitted to the appropriate agency representative assigned to the FBSC. View the complete roster.

The National Wildfire Coordinating Group (NWCG) provides national leadership to enable interoperable wildland fire operations among federal, state, Tribal, territorial, and local partners. NWCG operations standards are interagency by design; they are developed with the intent of universal adoption by the member agencies. However, the decision to adopt and utilize them is made independently by the individual member agencies and communicated through their respective directives systems.

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ETC Equipment Bulletin: 25-003 Flame-Resistant Shirt Survey

Date: June 12, 2025
Questions?  Please contact:
Equipment Technology Committee

The U.S. Forest Service National Technology and Development Program (NTDP) is seeking input on the Forest Service-designed flame-resistant (FR) shirt, currently available through the National Interagency Support Cache system and FedMall.

NTDP is conducting a product review to improve future FR shirt designs. As part of this effort, a short survey is now open for federal employees who have worn any of three recent FR shirt models. Feedback will guide design improvements to better meet the needs of wildland firefighters.

To comply with the Paperwork Reduction Act, responses are limited to federal employees. The survey is open through September 12, 2025. 

References:

NWCG Alerts

ETC Equipment Bulletin: 25-003

NEW! S-130, Firefighter Training (Blended) Now Available

Date: June 10, 2025
If you have questions, please visit our FAQ page. 
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The S-130, Firefighter Training (Blended), equips new wildland firefighters with essential skills through a mix of online learning and hands-on training. The course features a required online component and an instructor-led exercise, reinforcing online concepts with practical performance-based training.

The course builds competencies in wildland fire operations, safety, and equipment use, applicable across various operational environments. Both the online component and instructor-led field exercise must be completed to receive a certificate of completion. Students are required to finish the prerequisite S-190, Introduction to Wildland Fire Behavior, before enrolling in S-130, Firefighter Training (Blended).

References:

S-130, Firefighter Training (Blended)

S-190, Introduction to Wildland Fire Behavior

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EMC Memo 25-001: Interim Rapid Extraction Module (REMS) Training and Qualification Requirements

Date: June 3, 2025
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Emergency Medical Committee

The Emergency Medical Committee has issued interim guidance for Rapid Extraction Module Support (REMS) teams. Until further notice, Type I and II REMS teams must designate a team leader qualified at Firefighter Type 1 Squad Boss (FFT1) or higher. This temporary change replaces the Single Resource Boss (SRB) requirement, which is currently not feasible due to administrative barriers.

This memorandum does not include any other changes to the NWCG Standards for Rapid Extraction Module Support, PMS 552. This interim change takes effect immediately and will remain in place until further notice.

References:

EMC Memo 25-001: Interim Rapid Extraction Module (REMS) Training and Qualification Requirements

NWCG Standards for Rapid Extraction Module Support, PMS 552

Equipment Bulletin 25-002: Chaps, Chain Saw, M-2020, Nonconformities Affecting Use, Appearance, and Serviceability

Date: June 2, 2025
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Equipment Technology Committee

The Equipment Technology Committee issued Equipment Bulletin: 25-002 to address a manufacturing nonconformity affecting Forest Service specification, 6170-4K Chain Saw Chaps. The issue applies to chaps manufactured in 2024 and 2025 and distributed through FedMall. These chaps may have incorrectly bound edges that expose inner protective layers.

Independent purchasers should inspect all chain saw chaps received from FedMall beginning in 2024, prior to use. Review the full Equipment Bulletin: 25-002 for inspection criteria and recommended actions.

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NWCG Alerts

ETC Equipment Bulletin: 25-002