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PMS 437

Fire Assessment: Observing Current Fire Behavior

  1. Visual Fire Behavior Descriptions
  2. Observing Flame Length vs. Flame Height
  3. Rate of Spread Estimator
  4. Fire Behavior Observation Reports

Visual Fire Behavior Descriptions

This guide identifies key terms for describing fire behavior and provides reference imagery and descriptive detail to aid observation reports.

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Fire Observation/Description.

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Observing Flame Length vs. Flame Height

Observing Flames, as proxy for fireline intensity and indicator of tactical limitations, requires careful observation of flame length versus flame height. It is also important to identify whether the observation is for head, flank, or back of the fire.

Flame Length: The distance measured from the average flame tip to the middle of the active flaming zone at the base of the fire. It is measured on a slant when the flames are tilted due to effects of wind and slope.

Flame Height: The average height of flames as measured vertically, up, and down. It is estimated by comparing the flame to a nearby object of known height. Flame height is needed to estimate spot distance from a burning pile.

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Flame length is commonly estimated and referenced as analogous to the fireline intensity one would feel at the actively burning perimeter. Flame Height, on the other hand, is what most observers commonly report. Encourage users to identify and observe correctly.

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Rate of Spread Estimator

From the NWCG Standards for Wildland Fire Module Operations, PMS 430.

Fireline observers can use this table to look up a spread rate based on how long it takes the flaming front to move a given distance.

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Estimating Rate of Spread.

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Fire Behavior Observation Reports

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Fire Behavior Observation Form.

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NWCG Latest Announcements

2024 Week of Remembrance

Date: June 27, 2024
Contact: 6 Minutes for Safety Subcommittee 

As we approach the 2024 Week of Remembrance (WOR), June 30 to July 6, we dedicate this time to thoughtfully reviewing and recognizing the events of the 2018 Mendocino Complex. As such, this year’s theme of “Learning From the Mendocino Complex” embodies a longstanding hallmark of WOR, honoring through learning.

Throughout the week, our energy will be directed toward fostering generative conversations in briefing rooms and at tailgates.

References:

6 Minutes for Safety - 2024 Week of Remembrance

Wildland Fire Lessons Learned Center

Updated NWCG Wildland Fire Risk and Complexity Assessment, PMS 236

Date: June 24, 2024
Contact: Incident and Position Standards Committee 

The June 2024 update of the NWCG Wildland Fire Risk and Complexity Assessment, PMS 236, is now available to meet the current needs for incident management typing.

The NWCG Wildland Fire Risk and Complexity Assessment should be used to evaluate firefighter safety issues, assess risk, and identify the appropriate incident management organization based on incident complexity. Assessing risk, determining incident complexity, and identifying an appropriate incident management organization is a subjective process based on examining a combination of indicators or factors, which can change over time.

References:

NWCG Wildland Fire Risk and Complexity Assessment, PMS 236

Operations Branch Director (OPBD) Next Gen PTB Available

Date: June 10, 2024
Contact: NWCG Feedback 

The NWCG Position Task Book for Operations Branch Director (OPBD), PMS 311-109 is now available for use within the OPBD position qualification pathway. As part of the transition to Complex Incident Management (CIM), the OPBD Next Gen PTB was developed and the position qualification pathway updated.

More information about the Next Gen PTB format can be found on the NWCG Position Task Book webpage.

References:

Operations Branch Director Position Page

Operations Branch Director Next Gen PTB

NWCG Position Task Books

Updated NWCG Standards for Interagency Incident Business Management, PMS 902

Date: June 5, 2024
Contact: NWCG Incident Business Committee 

The 2024 revision of the NWCG Standards for Interagency Incident Business Management, PMS 902 is now available. The uniform application of interagency incident business management standards is critical to interagency fire operations. PMS 902 assists NWCG agencies in constructively working together to provide effective execution of each agency's incident business management program.

References:

PMS 902