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8.5 Map Spread

Map spread, in inches, is the size of a fire as scaled to a map. See Section 5.3 for more detailed information.

Example 1. For a rate of spread of 4 chains/hour and a projection time of 3 hours, find the map distance for the fire spread. Plot the distance using a tenths ruler for accuracy. The map scale is 1:24,000.

Step 1. Convert the map scale to feet per inch. 24,000 in × 1 foot/12 in = 2000 feet.

Step 2. Convert the spread distance to feet. 12 chains × 66 feet/chain = 792 feet.

Step 3. Convert the ground spread distance to a map spread distance. 792 feet × 1 inch/2000 feet = 0.4 inch

Step 4. Using a ruler, measure the distance from the point of origin to the distance of the fire spread.

Map spread distance is 0.4 inch.

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RMC Memo 25-01: Summary of Updates to Safety Officer Positions

Date: April 9, 2025
Questions?  Please contact:
RMC Member Eric Fransted

The Risk Management Committee (RMC) serves as the position steward for all Safety Officer incident positions and continues to improve position standards, training, and naming conventions. The implementation of Complex Incident Management (CIM) required changes to position titles. RMC collaborated with the NWCG Incident Position Standards Committee (IPSC) to propose and implement these updates. 

References:

RMC Memo 25-01: Summary of Updates to Safety Officer Positions 

NWCG Position Catalog

Updated, NWCG Guide to Wildland Fire Origin and Cause Determination, PMS 412

Date: April 8, 2025
Questions?  Please contact:
Wildland Fire Investigation Subcommittee

PMS 412 provides guidance for wildland fire investigations. This guide outlines recommended procedures, practices, techniques, and methods to promote a systematic approach. The last update to this publication was in 2016.

References:

NWCG Guide to Wildland Fire Origin and Cause Determination PMS 412

Updated NWCG Standards for Airtanker Base Operations, PMS 508

Date: March 31, 2025
Questions?  Please contact:
Airtanker Base Operations Unit

The updated NWCG Standards for Airtanker Base Operations (SABO), PMS 508 standardizes operations and procedures at interagency airtanker bases to ensure safe, efficient, and effective operations in support of interagency goals and objectives.

References:

NWCG Standards for Airtanker Base Operations, PMS 508

WFSTAR 2025 Core Component Module Package and 2024 Fire Year in Review Now Available

Date: March 14, 2025
Questions?  Please contact:
Joe Schindel at mschindel@blm.gov
 

The 2025 Core Component Module Package for RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR) and the 2024 Fire Year in Review are now available on the NWCG website. The 2025 Core Component Module Package provides all content needed to deliver RT-130.

References:

2025 Core Component Module Package

2024 Fire Year in Review Module