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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

NWCG Latest Announcements

2025 Week of Remembrance

Date: June 27, 2025
Questions?  Please contact:
6 Minutes for Safety Subcommittee

As we approach the 2025 Week of Remembrance (WOR), June 30–July 6, we dedicate this time to reflect on the past incidents from 2015 and honor the fallen through learning. Since its inception in 2014, WOR has honored wildland firefighters who made the ultimate sacrifice while encouraging critical discussions that reinforce lessons learned.

Throughout the week, we encourage thoughtful and generative conversations—whether in briefing rooms or at tailgates—that promote a culture of continuous learning and safety.

References:

2025 Week of Remembrance: Letter to Leadership

Wildland Fire Lessons Learned Center

ETC Equipment Bulletin: 25-003 Flame-Resistant Shirt Survey

Date: June 12, 2025
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Equipment Technology Committee

The U.S. Forest Service National Technology and Development Program (NTDP) is seeking input on the Forest Service-designed flame-resistant (FR) shirt, currently available through the National Interagency Support Cache system and FedMall.

NTDP is conducting a product review to improve future FR shirt designs. As part of this effort, a short survey is now open for federal employees who have worn any of three recent FR shirt models. Feedback will guide design improvements to better meet the needs of wildland firefighters.

To comply with the Paperwork Reduction Act, responses are limited to federal employees. The survey is open through September 12, 2025. 

References:

NWCG Alerts

ETC Equipment Bulletin: 25-003

NEW! S-130, Firefighter Training (Blended) Now Available

Date: June 10, 2025
If you have questions, please visit our FAQ page. 
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submit your question using our Contact Us form. 
 

The S-130, Firefighter Training (Blended), equips new wildland firefighters with essential skills through a mix of online learning and hands-on training. The course features a required online component and an instructor-led exercise, reinforcing online concepts with practical performance-based training.

The course builds competencies in wildland fire operations, safety, and equipment use, applicable across various operational environments. Both the online component and instructor-led field exercise must be completed to receive a certificate of completion. Students are required to finish the prerequisite S-190, Introduction to Wildland Fire Behavior, before enrolling in S-130, Firefighter Training (Blended).

References:

S-130, Firefighter Training (Blended)

S-190, Introduction to Wildland Fire Behavior

Wildland Fire Learning Portal

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

Date: June 3, 2025
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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