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6.8 Intersection

Intersection is a method of locating a point on a map by intersecting lines from two known landmarks on the ground. Intersection is one method fire lookouts use in determining the location of a fire. The procedure is as follows:

  1. From the first position, point 1, take a compass reading of the object or fire.
  2. Adjust for declination.
  3. With a compass or protractor, plot this azimuth on the map.
  4. Draw a line from point 1 beyond the point of the object or fire.
  5. Move down the road to a second position, or radio to the second person's location and get that azimuth reading. Repeat steps 2 through 4.
  6. A third and maybe a fourth reading will help further describe the location.
  7. The object or fire is located where the individual lines cross.

Example 1 - Tom is at a lookout tower at point A. He spots a fire and takes a compass reading. The magnetic azimuth is 277°. He radios to John at tower B, who tells him his magnetic azimuth on the fire is 337°. The declination for the area is 16°E. Plot the lines to find the location of the fire. 

Step 1. Convert the magnetic azimuths to true azimuths by adjusting for declination (see Section 6.5).
277° + 16° = 293°
337°+ 16°= 353°

Step 2. Draw the lines of the azimuth from each point well past the fire.

2 lines crossing

Step 3. Read where the two lines intersect to get the location of the fire.

NWCG Latest Announcements

NEW! S-290, Intermediate Wildland Fire Behavior (Blended) Available Now

Date: Aug 15, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that the S-290, Intermediate Wildland Fire Behavior (Blended) training is now available on the Wildland Fire Learning Portal. S-290 (Blended) training combines online training and instructor-led training components that support individuals working towards any Single Resource Boss or Fire Effects Monitor incident qualifications.

This second course in the series collectively serves to develop fire behavior prediction knowledge and skills, and provides more detailed information on fuels, weather, and topography that affect wildland fire behavior for safety purposes.

Students are required to finish the prerequisite S-190, Introduction to Wildland Fire Behavior, before enrolling in S-290, Intermediate Wildland Fire Behavior (Blended).

References:

S-290, Intermediate Wildland Fire Behavior (Blended)

S-190, Introduction to Wildland Fire Behavior

Wildland Fire Learning Portal

NEW! S-271, Helicopter Crewmember (Blended) Now Available

Date: Aug 14, 2025
Questions? Please contact:
Interagency Helicopter Operations Subcommittee

The S-271, Helicopter Crewmember (Blended) is now available. Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Helicopter Crewmember (HECM) incident qualifications. 

S-271, Helicopter Crewmember (Blended) training combines online training and instructor-led training components. This course is designed to provide students with the knowledge and skills necessary to perform the duties of the HECM position, as described in the NWCG Incident Position Standards for Helicopter Crewmember, PMS 350-22.

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:

S-271, Helicopter Crewmember (Blended)

NWCG Helicopter Crewmember (HECM) Position Page

Wildland Fire Learning Portal

Incident Position Standards and Next Generation Position Task Books Now Available for FBAN and LTAN

Date: Aug 13, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that Incident Position Standards and Next Generation Position Task Books are now available for Fire Behavior Analyst (FBAN) and Long Term Fire Analyst (LTAN).

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, scheduled for January 2026.

References:

NWCG Fire Behavior Analyst Position Page

NWCG Long Term Fire Analyst Page

ETC/RMC Safety Bulletin: 25-001 New Guidance on Laundering Wildland Fire Clothing to Reduce Contamination

Date: Aug 8, 2025
Questions? Please contact:
Equipment Technology Committee
 Risk Management Committee

The Equipment Technology Committee (ETC) and the Risk Management Committee (RMC) have issued Safety Bulletin 25-001: Laundering to Decontaminate Wildland Fire Clothing. Recent research revealed that wildland fire flame-resistant pants and shirts can be contaminated with chemicals from combustion byproducts, including carcinogens, and that common laundering practices can effectively remove these harmful contaminants from wildland firefighter clothing more effectively than previously understood. It is recommended to decontaminate wildland fire clothing as frequently as possible. 

Frequently Asked Questions about this new information and how to implement recommendations can be found on the NWCG Alerts page. Read the complete ETC/RMC Safety Bulletin: 25-001 to learn more. 

References:

NWCG Alerts

ETC Safety Bulletin: 25-001

Frequently Asked Questions (FAQ) on Laundering to Decontaminate Wildland Fire Clothing

Equipment Technology Committee

Risk Management Committee