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Surface Fire Size and Shape

  1. Surface Fire Shape
  2. Surface Fire Area Estimation from Point Source Fire, in Acres
  3. Surface Fire Perimeter Estimation from Point Source Fire, in Chains

These tools are intended for use with initiating fires only. Use the known ignition time and the number of hours after that you are interested in. Consider using:

  • Number of hours from ignition until the end of the expected burn period.
  • Number of hours until you arrive at the fire.

Surface Fire Shape

Remember that effective windspeed, as referenced here, is based on midflame windspeed.

Length to Width Ratio in parenthesis

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Surface Fire Elliptical Shape - These elliptical fire shapes demonstrate the effect of midflame windspeed and point out the length to width ratio in each case.

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Surface Fire Area Estimation from Point Source Fire, in Acres

Table 1, Spread Distance 1–50 Chains

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Surface Fire Area, Table 1 (1—50 chains spread distance).

Table 2, Spread Distance 52–165 Chains

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Surface Fire Area, Table 2 (52-165 chains spread distance).

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Surface Fire Perimeter Estimation from Point Source Fire, in Chains

Table 3, Spread Distance 1–50 Chains

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Surface Fire Perimeter, Table 3 (1—50 chains spread distance).

Table 4, Spread Distance 52–165 Chains

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Surface Fire Perimeter, Table 4 (52-165 chains spread distance).

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NWCG Latest Announcements

National Wildland Firefighter Day

Date: July 2, 2025
Questions?  Please contact:
National Interagency Fire Center

The National Wildfire Coordinating Group (NWCG) recognizes July 2, 2025, as National Wildland Firefighter Day (NWFFD). Established in 2022, NWFFD honors the dedication of wildland firefighters and support personnel. This day falls within the 2025 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.

NWCG provides leadership to enable interoperable wildland fire operations among federal, state, local, Tribal, and territorial partners. NWCG standards and training establish common practices to contribute to safe, effective, and coordinated interagency wildland fire operations nationwide.

References:

Week of Remembrance

National Wildland Firefighter Day

2025 Week of Remembrance

Date: June 27, 2025
Questions?  Please contact:
6 Minutes for Safety Subcommittee

As we approach the 2025 Week of Remembrance (WOR), June 30–July 6, we dedicate this time to reflect on the past incidents from 2015 and honor the fallen through learning. Since its inception in 2014, WOR has honored wildland firefighters who made the ultimate sacrifice while encouraging critical discussions that reinforce lessons learned.

Throughout the week, we encourage thoughtful and generative conversations—whether in briefing rooms or at tailgates—that promote a culture of continuous learning and safety.

References:

2025 Week of Remembrance: Letter to Leadership

Wildland Fire Lessons Learned Center

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. 
If your question is not answered there, you can 
submit your question using our Contact Us form. 
 

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

Wildland Fire Learning Portal