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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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NWCG Latest Announcements

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

Date: June 2, 2025
Questions?  Please contact:
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.

References:

NWCG Alerts

ETC Equipment Bulletin: 25-002

2024 Wildland Fire Emergency Medical Service Awards

Date: May 22, 2025
Questions?  Please contact:
Emergency Medical Committee

The NWCG Emergency Medical Committee (EMC) is proud to announce the recipients of the 2024 Wildland Fire Emergency Medical Service Awards. Each year, EMC recognizes individuals and groups who have demonstrated exceptional actions or accomplishments that go above and beyond their normal mission or job duties.

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

References:

2024 Wildland Fire EMS Awards

NWCG Emergency Medical Committee

NWCG Welcomes the Incident Management Teams Association as an Associate Member

Date: May 21, 2025
Questions?  Please contact:
https://www.nwcg.gov/contact-us

The NWCG Executive Board is honored to announce that the Incident Management Teams Association (IMTA) has joined the National Wildfire Coordinating Group as an associate member.

IMTA is a dedicated group of incident management professionals committed to enhancing the profession by promoting standards and fostering collaboration across federal, state, local, Tribal, and private sector partners throughout all phases of incident management.

“Joining NWCG aligns with our mission to elevate incident management professionals nationwide,” said Dr. Randal Collins, President of IMTA. “This is a proud moment for all of us committed to advancing public safety.”

References:

Incident Management Teams Association

National Wildfire Coordinating Group

Updated NWCG Guide for Wildland Fire Modules, PMS 431

Date: May 14, 2025
Questions?  Please contact:
Fire Use Subcommittee

The updated NWCG Guide for Wildland Fire Modules, PMS 431 serves as a supplemental resource for wildland fire module operations, providing information frequently used in the field.

PMS 431 defines the organizational structure, staffing, and qualifications for Type 1 and Type 2 Wildland Fire Modules, outlining their roles in wildland fire suppression, prescribed fire, and resource management. The NWCG Guide for Wildland Fire Modules, PMS 431, should be used in conjunction with the NWCG Standards for Wildland Fire Module Operations, PMS 430.

References:

NWCG Guide for Wildland Fire Modules, PMS 431

NWCG Standards for Wildland Fire Module Operations, PMS 430