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Firefighter Math: 8.8 Probability and Number of Ignitions

Probability is the chance that an event will happen and is expressed in terms of percent, or per 100. For example, if there is a 40 percent chance of a spot fire starting, that means that out of 100 glowing embers that fly off, 40 embers will likely start spot fires, and 60 will not. Percent is calculated by changing the percent into a fraction by dividing by 100, then multiplying by the total number of possible situations.

Example 1 - The probability of ignition is 80 percent. How many ignitions are likely to occur if 90 glowing firebrands land on receptive fuel?

Step 1. Change 80 percent to a fraction, 80/100 and then into a decimal. 80/100 = 0.80

Step 2. Multiply by the total number of situations, in this case glowing firebrands. 0.8 × 90 = 72
 

Expect 72 ignitions out of 90 glowing firebrands

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NEW! S-231, Engine Boss Course Available Now

Date:  March 6, 2026
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Please contact: Incident Operations Subcommittee

NWCG is pleased to announce the new S-231, Engine Boss (Single Resource) course is now available on the Wildland Fire Learning Portal (WFLP). Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Engine Boss, Single Resource (ENGB) incident qualifications. 

This is a performance-based instructor-led training (ILT) that focuses on the application of ENGB responsibilities during wildland fire operations, emphasizing readiness, information gathering, risk management, engine tactics, and Wildland Urban Interface (WUI) operations. Trainees apply these skills through scenario-based group work and an optional field day that reinforces hands-on engine operation tasks. 

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NWCG Engine Boss, Single Resource (ENGB) Position Page

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NWCG Celebrates 50 Years!

Date:  March 6, 2026
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Please contact: NWCG Executive Secretary

NWCG is proud to celebrate 50 years of service to the wildland fire community. Beginning in 1976 with an interagency agreement between the Department of Interior and Department of Agriculture, NWCG has grown to include additional member agencies and is recognized as the standard-setting leader in wildland fire operations.

To honor where we’ve been and highlight where we are going, the NWCG team has created a video showcasing our history and accomplishments. The video is now available on the NWCG website.

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NWCG 50 Year Anniversary Video

NEW! S-131, Firefighter Type 1 Course Available Now

Date:  March 6, 2026
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Please contact: Incident Operations Subcommittee

NWCG is pleased to announce the new S-131, Firefighter Type 1 course is now available on the Wildland Fire Learning Portal (WFLP). Developed through the Incident Performance and Training Modernization (IPTM) effort, this course is a performance-based instructor-led training (ILT) that focuses on the application of situational awareness and decision making, building on the knowledge and concepts introduced in previous required courses. Using a threaded fictitious fire, each unit focuses on a performance-based activity in which students practice applying their decision-making and problem-solving skills.

The S-131, Firefighter Type 1 course is required for individuals seeking qualifications to be a Firefighter Type 1 (Squad Boss) (FFT1) or an Incident Commander Type 5 (ICT5).

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2026 Professional Reading List

Date: March 4, 2026
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Please contact: WFLDP Curriculum Management

The Wildland Fire Leadership Development Program (WFLDP) is announcing the 2026 Professional Reading List.  The goal of the annual reading list is to promote the reading and discussion of the selected books throughout the year. 

The six books chosen for this year are: How to Win Friends and Influence People by Dale Carnegie; Leadership Strategy and Tactics by Jocko Willink; Meditations by Marcus Aurelious; Quiet by Susan Cain; The Little Book of Stoic Quotes by Phil Van Treuren; and The Confident Mind by Nate Zinsser.

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Professional Reading Program

Wildland Fire Leadership Development Program