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PMS 437

Surface Fire Size and Shape

NWCG Committee Realignment Website Updates: Content will continue to be updated over the coming days as we work through final reviews and adjustments, and all publications and products are currently under revision.

  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

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

2026 Week of Remembrance

Date:  June 30, 2026
Questions? 
Please contact: 6 Minutes for Safety Subcommittee

As we approach the 2026 Week of Remembrance (WOR), June 30–July 6, we dedicate this time to reflect on past incidents from 2016 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 that promote a culture of continuous learning and safety.

References:

2026 Week of Remembrance: Letter to Leadership

Wildland Fire Lessons Learned Center

RMC Memorandum 26-02: SAFENET Modernization and SafeNetX Launch

Date:  June 25, 2026
Questions? 
Please contact: Risk Management Committee

The Risk Management Committee (RMC) is pleased to announce the launch of SafeNetX, the modernized safety reporting system now available to the wildland fire community. Effective June 15, 2026, SafeNetX enables reporting of unsafe, unhealthy, near-miss, and high-risk operations across wildland fire, all-hazard incidents, training, and related work environments.

SafeNetX is the result of a multi-agency modernization effort led by RMC, which began evaluating improvements to the legacy SAFENET system in 2021. To learn more, read the full RMC memorandum in the links provided.

References:

SafeNetX

RMC Safety Memorandum 26-02: SAFENET Modernization and SafeNet X Launch

2025 Wildland Fire EMS Awards

Date:  June 12, 2026
Questions? 
Please contact: Emergency Medical Committee

The NWCG Emergency Medical Committee (EMC) announces the recipients of the 2025 Wildland Fire Emergency Medical Service (EMS) Awards. EMC annually recognizes individuals and groups who have demonstrated outstanding actions or accomplishments that are above and beyond the expectation of one’s normal mission or job duties.

Congratulations to all the awardees and nominees. Through leadership and initiative, they have made significant contributions to the safety of the wildland fire community. These awards are well deserved.

References:

2025 Wildland Fire EMS Awards

Emergency Medical Committee

Incident Position Standards and the Next Generation Position Task Book Now Available for RAMP

Date:  June 12, 2026
Questions? 
Please contact: Airtanker Base Operations Unit

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Book are now available for Ramp Manager (RAMP).

The Performance Support Package for this position was developed as part of the Incident Performance and Training Modernization effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

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 release in January 2027.

References:

NWCG Ramp Manager Position Page

National Interagency Aviation Committee