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8.6 Head, Flank, and Rear Fire Terms

Each side of the fire is described in terms of head, flank, and rear. The head is the fastest spreading part of a fire's perimeter. The head is usually the side toward which the wind is blowing, and will also often be the upslope side of a fire. The head of the fire is of primary interest. 

The right and left flanks describe the sides of the fire. Flanks are perpendicular to the head of the fire. 

The rear of the fire is the side of the fire opposite the head.
 

screengrab of animation of fire spread
Click on the graphic above to view animation of fire spread along head, flank, and rear

Example 1 - Plot the perimeter and label the head, rear, and flanks of a fire with ROS of 4 chains/hour and PT of 3 hours. Assume the wind is blowing from left to right across the page.  
 

flank image

The head of the fire on your drawing should correspond to the edge of the fire's forward perimeter at the projection time. The distance from head to rear will correspond to the spread distance, in this case 12 chains.

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Updated! L-280, Followership to Leadership (Instructor-led) Course

Date: October 3, 2024
Questions? Please contact:
Leadership Committee

NWCG is pleased to announce the updated L-280, Followership to Leadership (Instructor-led) course is now available. L-280 is intended for operational personnel at the Firefighter Type 1 level, and for individuals pursuing Leadership Level 2, New Leader. 

This instructor-led course is a primer on leadership and the second formal course in the Wildland Fire Leadership Development Program. It helps emerging leaders build the confidence, skills, and mindset needed to lead effectively in high-risk environments. 

For more information about leadership development and available courses, visit the Leadership Committee Web Portal.

References:

L-280, Followership to Leadership (Instructor-led)

Wildland Fire Leadership Development Program

Wildland Fire Learning Portal

Equipment Advisory 25-01: Pre-2006 Fire Shelter Degradation and Discontinuation of Use

Date: Sept 26, 2025
Questions? Please contact:
Equipment Technology Committee 

The Equipment Technology Committee (ETC) has released Equipment Advisory 25-01: Pre-2006 Fire Shelter Degradation and Discontinuation of Use. This advisory recommends all pre-2006 fire shelters should be removed from service by January 1, 2026.

This advisory recommends firefighters and fire managers to:

  • Inspect fire shelters immediately
  • Replace and destroy any pre-2006 shelters (identified by white or pink insert label)
  • Order replacements as needed

For further details, please refer to the complete advisory. 

References:

Equipment Advisory 25-01: Pre-2006 Fire Shelter Degradation and Discontinuation of Use

NWCG Fire Inspection Flowchart, PMS 411-1

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NEW! S-219, Firing Operations (Blended) Now Available

Date: Sept 11, 2025
Questions? Please contact:
Fuels Management Committee 

The S-219, Firing Operations (Blended) course is now available on the Wildland Fire Learning Portal. Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Firing Boss, Single Resource (FIRB) incident qualifications.

This blended course combines online and instructor-led training to provide students with the knowledge and skills required to perform the duties of the FIRB, as described in the NWCG Incident Position Standards for Firing Boss, Single Resource, PMS 350-105.

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 2026.

References:

S-219, Firing Operations (Blended)

NWCG Firing Boss, Single Resource Position Page

Wildland Fire Learning Portal

NWCG Committees Observe Suicide Prevention Awareness Week: September 7-13, 2025

Date: Sep 5, 2025
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Mental Health Subcommittee

The NWCG Mental Health Subcommittee (MHSC) and Risk Management Committee (RMC) recognize the unique challenges and demands faced by the wildland fire community. The MHSC and RMC know that we are all stronger together and believe in fostering a culture of support, understanding, and resilience.

Suicide Prevention Awareness encourages us to actively connect with and support each other. For more information that could make a difference for yourself or someone else please review the materials and resources provided for the 2025 Suicide Prevention Awareness Week.

References:

2025 Suicide Prevention Awareness Week Materials and Resources