Surface Fire Size and Shape

Surface Fire Shape
Surface Fire Area Estimation from Point Source Fire, in Acres
- Table 1, Spread Distance 1-50 Chains
- Table 2, Spread Distance 52-165
Surface Fire Perimeter Estimation from Point Source Fire, in Chains
- Table 3, Spread Distance 1-50 Chains
- Table 4, Spread Distance 52-165 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

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

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

Table 2, Spread Distance 52–165 Chains

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

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

Table 4, Spread Distance 52–165 Chains

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

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NWCG Latest Announcements

2025 NWCG Incident Response Pocket Guide (IRPG), PMS 461, Now Available

Date: February 27, 2025
Contact: Incident Operations Subcommittee

NWCG is excited to announce that the 2025 NWCG Incident Response Pocket Guide (IRPG), PMS 461, is now available. Visit NWCG's website to learn about the major updates and changes in the 2025 version of the IRPG. The NWCG Guia de Respuesta de Incidente de Bolsillo (GRI), PMS 461-ES is available electronically and will be available from Great Basin Cache by early summer 2025.

All hard copy materials, including the IRPG, are ordered through the Great Basin Cache (GBK). Information on the ordering process can be found in the National Fire Equipment System (NFES) Catalog.

References:

2025 IRPG Information

NWCG Incident Response Pocket Guide (IRPG), PMS 461

NWCG Guia de Respuesta de Incidente de Bolsillo (GRI), PMS 461-ES

NWCG NFES Catalog - Part 2: Publications, PMS 449-2

2025 Professional Reading Program

Date: February 18, 2025
Contact: Wildland Fire Leadership Development Program (WFLDP)

The Wildland Fire Leadership Development Program is announcing the 2025 Professional Reading list! The goal of the annual reading list is to promote the reading and discussion of the books throughout the year.

The five books chosen for this year are: Surf When You Can by Brett Crozier, Man’s Search for Meaning by Viktor E. Frankl, Elephant Company by Vicki Constantine Croke, Simply Managing by Henry Mintzberg, and Chop Wood Carry Water by Joshua Metcalf.

References:

Professional Reading Program

Task Group Volunteers Needed to Update the Property Loss or Damage Report, OF 289

Date: February 5, 2025
Contact: Julie Bennett, Incident Business Committee Chair

The Incident Business Committee (IBC) is requesting volunteers for a new task group to revise the 1981 version of the Property Loss or Damage Report, OF 289 and create an incident replacement job aid. The volunteers may be recruited from within or outside the Geographic Area Incident Business Committees.

References:

IBC Memorandum 25-02

IBC Correspondence

2025 Updates to the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

Date: February 4, 2025
Contact: Incident and Position Standards Committee

The NWCG Incident and Position Standards Committee has updated the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

These updates address changes to incident position names and requirements for qualification, training, and experience. Updates related to the implementation of Complex Incident Management (CIM) are also included.

The NWCG Wildland Fire Position Qualification Flowchart, PMS 308 has also been updated to reflect the recent changes.

References:

NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

NWCG Wildland Fire Position Qualification Flowchart, PMS 308

NWCG Memo: 2025-01 January 2025 Updates to the NWCG Standards for Wildland Fire Positions Qualifications, PMS 310-1

National Wildfire Coordinating Group

Surface Fire Size and Shape

Surface Fire Shape

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

Length to Width Ratio in parenthesis

Surface Fire Area Estimation from Point Source Fire, in Acres

Table 1, Spread Distance 1–50 Chains

Table 2, Spread Distance 52–165 Chains

Surface Fire Perimeter Estimation from Point Source Fire, in Chains

Table 3, Spread Distance 1–50 Chains

Table 4, Spread Distance 52–165 Chains

NWCG Latest Announcements

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References:

References:

References:

NWCG

National Wildfire Coordinating Group

Weather

Fuels

Fuel Moisture

Mapping

Surface Fire

Crown Fire

Fire Assessment

Fire Danger

CFFDRS

Surface Fire Size and Shape

Surface Fire Shape

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

Length to Width Ratio in parenthesis

Surface Fire Area Estimation from Point Source Fire, in Acres

Table 1, Spread Distance 1–50 Chains

Table 2, Spread Distance 52–165 Chains

Surface Fire Perimeter Estimation from Point Source Fire, in Chains

Table 3, Spread Distance 1–50 Chains

Table 4, Spread Distance 52–165 Chains

NWCG Latest Announcements

References:

References:

References:

References:

NWCG National Wildfire Coordinating Group

NWCG

National Wildfire Coordinating Group