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6.9 Resection

Resection is a method of finding one's own location on a map by sighting two known landmarks.
The procedure is as follows:

  1. Find at least two landmarks on the map that can be also identified on the ground. With a compass measure an azimuth to each of the landmarks on the ground.
  2. Adjust for declination.
  3. Convert to back azimuths.
  4. Using the two known landmarks on the map, draw the lines of the back azimuths until the lines cross.
  5. The location is where the two lines cross.

 

Example 1 - Mario is in the woods and is unsure of his current location. He sees two peaks in the distance and locates them on his map. He takes the azimuth reading of the first peak and gets 327°
. He takes a reading for the second peak and gets an azimuth reading of 83°. The declination for the area is 17°W. Find Mario's location on the map below.

Step 1. Convert the magnetic azimuths to true azimuths (see Section 6.5). 
327° - 17° = 310° 
83° - 17° = 66°

Step 2. Convert to back azimuths.
310° - 180°= 130°
66° + 180°= 246°

Step 3. From the two known landmarks on the map, draw the lines of the back azimuths until the lines intersect.

Azimuths of lines

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NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212, and Next Generation Position Task Book for Basic Faller Are Now Available

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The updated NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212, and NWCG Position Task Book for Basic Faller (FAL3), PMS 311-19 are now available.

The NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212 includes position standards designed to be used in conjunction with the Next Generation Position Task Book (Next Gen PTB). The Next Gen PTB for Basic Faller (FAL3) includes an evaluation guide with suggested rating elements to consider when assessing trainees.

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

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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. 

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

Date: April 8, 2025
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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.

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NWCG Guide to Wildland Fire Origin and Cause Determination PMS 412

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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.

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NWCG Standards for Airtanker Base Operations, PMS 508