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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

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

Date: June 3, 2025
Questions?  Please contact:
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
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