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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

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

Updated NWCG Standards for Wildland Fire Resource Typing, PMS 200 Now Includes Off-Highway Vehicle Typing Standards

Date: May 13, 2025
Questions?  Please contact:
Mobile Fire Equipment Subcommittee 

The NWCG Standards for Wildland Fire Resource Typing, PMS 200 has been updated to include newly developed Off-Highway Vehicle (OHV) typing standards. These standards organize OHV information into logical categories and outline key safety requirements for occupants.

NWCG Standards for Wildland Fire Resource Typing, PMS 200 establishes minimum typing standards for aircraft, crews, and equipment used in national mobilization to wildland fire incidents. Typing designations are assigned based on measurable capability and performance criteria.

References:

NWCG Standards for Wildland Fire Resource Typing, PMS 200