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Firefighter Math: 6.6 Vectors

A vector has a magnitude (often representing distance or speed) and direction. When a clinometer (see Section 4.5) is used to estimate the slope percent and the slope length is measured with a metal tape, the result is a vector. The slope length represent the magnitude and the slope percent can be converted into a slope angle that represents direction. Vectors can provide information about the distance and direction of fire spread, or the speed and direction of fire spread or wind. 

Example 1 - Linda is standing at point A. John is standing at point B. John reads the clinometer and finds a slope percent of 25 percent. They measure the slope length and get 18 feet. Draw the vector from point A and then again from point B.

Step 1. Following the steps in Section 4.5, convert the 25 percent to an angle with a calculator using inverse tan (tan-1).

tan A = 0.25, angle A = 14°

Step 2. Draw the vectors. 

image of vectors drawn with length and angle

WIND VECTORS

Wind is the horizontal movement of air relative to the surface of Earth. Recall from Section 6.2 that the wind direction is named by the direction from which the wind is blowing. If the wind is northerly, then the wind is coming from the north. When the wind is blowing into your face, the wind would be named from the direction you are facing. For example, Mandy is facing south and the wind is blowing into her face. The wind is said to be a southerly wind.

 

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2026 Updates to the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

Date: January 23, 2026
Questions? 
Please contact: Incident and Position Standards Committee

The Incident and Position Standards Committee has updated the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

These updates address changes to incident position names and requirements for qualification, training, and experience. Updates related to the implementation of Complex Incident Management (CIM) and Incident Performance Training Modernization (IPTM) are also included.

The NWCG Wildland Fire Position Qualification Flowchart, PMS 308 has also been updated to reflect the recent changes.

References:

NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

NWCG Wildland Fire Position Qualification Flowchart, PMS 308

IPSC Memo 26-01: January 2026 Updates to the NWCG Standards for Wildland Fire Positions Qualifications, PMS 310-1

Incident Business Committee Memo 26-01: Updated Emergency Equipment Shift Ticket, OF 297

Date: January 22, 2026
Questions? 
Please contact: Incident Business Committee

The Incident Business Committee (IBC) has released Memorandum 26-01: OF 297 and 2026 Fire Use. This memo informs the wildland fire community that the updated Emergency Equipment Shift Ticket, OF 297 is available for download and can be ordered through the Great Basin Cache.

Beginning January 15, 2026 the previous version of the OF 297 form has been discontinued.

For further details, please contact your IBC representative.

References:

Incident Business Committee Memorandum 26-01

Great Basin Cache

NEW! S-390, Introduction to Wildland Fire Behavior Calculations (Blended) Available Now

Date: December 22, 2025
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Please contact: Fire Behavior Subcommittee

NWCG is excited to announce that the new S-390, Introduction to Wildland Fire Behavior Calculations (Blended) training is now available on the Wildland Fire Learning Portal.

This third course in the series combines online and instructor-led training components aimed at individuals who are involved in planning, managing, and executing wildland fire and prescribed burn operations; who require a thorough understanding of fire behavior calculations to enhance effectiveness and safety. This includes students who require the knowledge and skill necessary to perform the duties of a Type 3 Incident Commander (ICT3), Division/Group Supervisor (DIVS), or Prescribed Fire Burn Boss Type 2 (RXB2).

Students are required to be qualified as any Single Resource Boss position and complete the prerequisite S-290, Intermediate Wildland Fire behavior (Blended) course, before enrolling in S-390.

References:

S-390, Introduction to Wildland Fire Behavior Calculations (Blended)

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NEW! S-320, Introduction to Incident Management Teams (Blended) Available Now

Date: December 18, 2025
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NWCG is excited to announce that S-320, Introduction to Incident Management Teams (Blended) is now available on the Wildland Fire Learning Portal!

This blended course combines online learning with instructor-led training, designed for individuals seeking to build leadership skills and gain experience in incident management.

Students are required to complete the prerequisite trainings ICS-100, Introduction to Incident Command System (ICS), ICS-200, Basic ICS for Initial Response, and ICS-700, An Introduction to the National Incident Management System (NIMS) prior to attending S-320.

References:

S-320, Introduction to Incident Management Teams (Blended)

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