Skip to main content

6.7 Closed Traverse

A closed traverse is a series of connected lines whose lengths and bearings are measured off these lines (or sides), which enclose an area. A closed traverse can be used to show the shape of the perimeter of a fire or burn area. If you were to pace continuously along the sides of a closed traverse, the finishing point would be the same as the starting location.

Note in the following sketch how the traverse is followed clockwise. If the direction was followed counterclockwise at any point, the bearing letters would change to their opposites but the numbers would not, as shown in the first sketch (1) below. The second sketch (2) is a closed traverse. Here, the series of lines completes a distance area, and the starting and ending points are the same.
 

Traverse Examples

Example 1 - Jeff paced the perimeter of the Zavala fire. His pace is 13 paces/chain. The declination for his current location is 14.5°E. The direction, distance, and travel for Jeff is as follows: Jeff begins at point 1 and goes N42°W for 27 paces; from point 2 he goes N75°W for 16-1/2 paces; from point 3 he goes N31°W for 24-1/2 paces; from point 4 he goes N36°E for 29-1/2 paces; from point 5 he goes S65°E for 22 paces; from point 6 he goes S13°E for 52-1/2 paces; from point 7 he goes S21°W for 10-1/4 paces back to the starting point, point 1.

Convert the bearings to magnetic readings. Adjust the magnetic readings to true north readings. Plot the closed traverse in feet using an engineer's tenth ruler and protractor.

Step 1. Convert paces into feet. Jeff's pace is 13 paces per chain. Set up the cancellation table (Section 2.1) and solve for distance in feet.

cancellation table
Repeat this step for each distance.

Step 2. Convert the bearings to magnetic readings. See Section 6.1.

The NW quadrant is between 270° and 360°. 360° - 42° = 318° 
The SE quadrant is between 90° and 180°. 180° - 65° = 115°
The NE quadrant is between 0° and 90° so those values are used as recorded.
The SW quadrant is between 180° and 270°. 180° + 21° = 201°

The resulting magnetic reading are listed in the table below. 

Step 3. Adjust each magnetic reading to a true reading following the guidelines in Section 6.5.

Closed Traverse

Step 4. Choose a scale. 1/10 inch = 10 feet

Step 5. Using a protractor (angles measured in degrees) and an engineer's scale or tenth's ruler, plot the plan view of the traverse horizontal distance (feet) and the bearing (degrees) between points.

image of protractor measuring angles

image of engineer's rule

Step 5a. Set the protractor so the 0°/180°line is up (north) and on a north-south axis.

Step 5b. Put a point in the middle hole. This will be point 1.

Step 5c. Read 318° on the outer scale of the protractor.
Put a dot to mark the point.

index point on protractor


Step 5d. Draw a line from point 1 up to the dot that is 13-7/10 marks (each inch has 10 marks).

ruler with points

Step 5e. The end of this line will be point 2. Put the hole of the protractor on point 2. Follow steps 5b and 5c with each of the values.

When plotting the values that are in the southern quadrants with a semicircle protractor, rotate the protractor so the 0°/180°line is down (facing south) and read the numbers on the inner scale. Continue to complete all the points. The end result should be a closed traverse as shown.

Step 5f. Convert the true readings to bearings. 

P1 to P2 = 360° - 332.5° = N27.5°W
P2 to P3 = 360° - 299.5° = N60.5°W
P3 to P4 = 360° - 343.5° = N16.5°W
P4 to P5 = 0° + 50.5° = N50.5°E
P5 to P6 = 180° - 129.5° = S50.5°E
P6 to P7 = 181.5° - 180° = S1.5°E
P7 to P1 = 215.5° - 180° = S35.5°W

Label the lines of the traverse with the corresponding bearings.

 

NWCG Latest Announcements

EMC Memo 25-001: Interim Rapid Extraction Module (REMS) Training and Qualification Requirements

Date: June 3, 2025
Questions?  Please contact:
Emergency Medical Committee

The Emergency Medical Committee has issued interim guidance for Rapid Extraction Module Support (REMS) teams. Until further notice, Type I and II REMS teams must designate a team leader qualified at Firefighter Type 1 Squad Boss (FFT1) or higher. This temporary change replaces the Single Resource Boss (SRB) requirement, which is currently not feasible due to administrative barriers.

This memorandum does not include any other changes to the NWCG Standards for Rapid Extraction Module Support, PMS 552. This interim change takes effect immediately and will remain in place until further notice.

References:

EMC Memo 25-001: Interim Rapid Extraction Module (REMS) Training and Qualification Requirements

NWCG Standards for Rapid Extraction Module Support, PMS 552

Equipment Bulletin 25-002: Chaps, Chain Saw, M-2020, Nonconformities Affecting Use, Appearance, and Serviceability

Date: June 2, 2025
Questions?  Please contact:
Equipment Technology Committee

The Equipment Technology Committee issued Equipment Bulletin: 25-002 to address a manufacturing nonconformity affecting Forest Service specification, 6170-4K Chain Saw Chaps. The issue applies to chaps manufactured in 2024 and 2025 and distributed through FedMall. These chaps may have incorrectly bound edges that expose inner protective layers.

Independent purchasers should inspect all chain saw chaps received from FedMall beginning in 2024, prior to use. Review the full Equipment Bulletin: 25-002 for inspection criteria and recommended actions.

References:

NWCG Alerts

ETC Equipment Bulletin: 25-002

2024 Wildland Fire Emergency Medical Service Awards

Date: May 22, 2025
Questions?  Please contact:
Emergency Medical Committee

The NWCG Emergency Medical Committee (EMC) is proud to announce the recipients of the 2024 Wildland Fire Emergency Medical Service Awards. Each year, EMC recognizes individuals and groups who have demonstrated exceptional actions or accomplishments that go above and beyond their normal mission or job duties.

Congratulations to all the awardees and nominees. Through leadership and initiative, they have made significant contributions to the safety and well-being of the wildland fire community. These honors are well deserved.

References:

2024 Wildland Fire EMS Awards

NWCG Emergency Medical Committee

NWCG Welcomes the Incident Management Teams Association as an Associate Member

Date: May 21, 2025
Questions?  Please contact:
https://www.nwcg.gov/contact-us

The NWCG Executive Board is honored to announce that the Incident Management Teams Association (IMTA) has joined the National Wildfire Coordinating Group as an associate member.

IMTA is a dedicated group of incident management professionals committed to enhancing the profession by promoting standards and fostering collaboration across federal, state, local, Tribal, and private sector partners throughout all phases of incident management.

“Joining NWCG aligns with our mission to elevate incident management professionals nationwide,” said Dr. Randal Collins, President of IMTA. “This is a proud moment for all of us committed to advancing public safety.”

References:

Incident Management Teams Association

National Wildfire Coordinating Group