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Week of Remembrance

Common Denominators of Fire Behavior On Tragedy Fires

 

Use the Incident Response Pocket Guide (IRPG), PMS 461, to review and discuss the five major common denominators of fire behavior on fatal and near-fatal fires. These common denominators have been identified through studies of tragedy fires. It is important for firefighters to readily recognize them to prevent future tragedies. 

Fire managers make decisions throughout the day on how to suppress fires and best use resources while protecting life and property. This Standard Firefighting Order depicts a firefighter observing increased fire behavior during a time of day when temperatures are high and relative humidity is low.

3. Base all actions on current and expected behavior of the fire. A firefighter looks at his watch, which reads 2 PM, while a fire actively grows in steep terrain and heavy timber.

3. Base all actions on current and expected behavior of the fire.

Read about all 10 Standard Firefighting Orders.

Such fires often occur:

  1. On relatively small fires or deceptively quiet areas of large fires.
  2. In relatively light fuels, such as grass, herbs, and light brush.
  3. When there is an unexpected shift in wind direction or in wind speed.
  4. When fire responds to topographic conditions and runs uphill.
  5. Critical burn period between 1400 and 1700.


Alignment of topography and wind during the critical burning period should be considered a trigger point to reevaluate tactics.

Blowup to burnover conditions generally occur in less than 60 minutes and can be as little as 5 minutes.
 

 

The time of Blow up shows the hour at which tragic fires occurred pointing to a watch on left.

 

 

A tactical pause may be prudent around 1400 for reevaluating your situational awareness of topography, fuels, and weather.

It can be used as an opportunity to remember that this is the beginning of a dangerous part of the day for fighting fires and increased caution is in order.

 

Category
Weather Fire Behavior
References
10 Standard Firefighting Orders, PMS 110
18 Watch Out Situations, PMS 118
10 and 18 Poster, PMS 110-18
Incident Response Pocket Guide (IRPG), PMS 461, Common Denominators of Fire Beh…

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NWCG Latest Announcements

Incident Position Standards and the Next Generation Position Task Books Now Available for ICT5 and FFT1

Date: July 29, 2025
Questions?  Please contact:
Incident Command Subcommittee
Incident Operations Subcommittee

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Incident Commander Type 5 (ICT5) and Firefighter Type 1 Squad Boss (FFT1).

The Performance Support Packages for these positions were 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 January 2026.

References:

NWCG Incident Commander Type 5 Position Page

NWCG Firefighter Type 1 Squad Boss Position Page

Incident Position Standards and the Next Generation Position Task Books Now Available for ATBM and FWBM

Date: July 28, 2025
Questions?  Please contact:
Airtanker Base Operations Unit

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Airtanker Base Manager (ATBM) and Fixed Wing Base Manager (FWBM).

The Performance Support Packages for these positions were 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 January 2026.

References:

NWCG Airtanker Base Manager Position Page

NWCG Fixed Wing Base Manager Position Page

Incident Position Standards and the Next Generation Position Task Books Now Available for PROC and TIME

Date: July 17, 2025
Questions?  Please contact:
Incident Business Committee

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Procurement Unit Leader (PROC) and Time Unit Leader (TIME).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization (IPTM) 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 update, scheduled for January 2026.

References:

NWCG Procurement Unit Leader Position Page

NWCG Time Unit Leader Position Page

National Wildland Firefighter Day

Date: July 2, 2025
Questions?  Please contact:
National Interagency Fire Center

The National Wildfire Coordinating Group (NWCG) recognizes July 2, 2025, as National Wildland Firefighter Day (NWFFD). Established in 2022, NWFFD honors the dedication of wildland firefighters and support personnel. This day falls within the 2025 Week of Remembrance (June 30 - July 6), providing an opportunity to renew our commitment to wildland firefighter safety while remembering those who have fallen in the line of duty.

NWCG provides leadership to enable interoperable wildland fire operations among federal, state, local, Tribal, and territorial partners. NWCG standards and training establish common practices to contribute to safe, effective, and coordinated interagency wildland fire operations nationwide.

References:

Week of Remembrance

National Wildland Firefighter Day