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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

Next Generation Position Task Book and Updated Incident Position Description Now Available for Operations Section Chief Complex

Date: February 27, 2025
Contact: Incident Operations Subcommittee

NWCG is excited to announce that Operations Section Chief Complex (OSCC) has a Next Generation NWCG Position Task Book for Operations Section Chief Complex (OSCC), PMS 311-108 and an updated Incident Position Description.

These resources support trainees, qualified personnel, and evaluators in their respective roles.

References:

NWCG Operations Section Chief Complex Position Page 

NWCG Operations Section Chief Complex Incident Position Description 

NWCG Position Task Book for Operations Section Chief Complex (OSCC), PMS 311-108 

2025 NWCG Incident Response Pocket Guide (IRPG), PMS 461, Now Available

Date: February 27, 2025
Contact: Incident Operations Subcommittee

NWCG is excited to announce that the 2025 NWCG Incident Response Pocket Guide (IRPG), PMS 461, is now available. Visit NWCG's website to learn about the major updates and changes in the 2025 version of the IRPG. The NWCG Guia de Respuesta de Incidente de Bolsillo (GRI), PMS 461-ES is available electronically and will be available from Great Basin Cache by early summer 2025.

All hard copy materials, including the IRPG, are ordered through the Great Basin Cache (GBK). Information on the ordering process can be found in the National Fire Equipment System (NFES) Catalog.

References:

2025 IRPG Information 

NWCG Incident Response Pocket Guide (IRPG), PMS 461 

NWCG Guia de Respuesta de Incidente de Bolsillo (GRI), PMS 461-ES 

NWCG NFES Catalog - Part 2: Publications, PMS 449-2 

2025 Professional Reading Program

Date: February 18, 2025
Contact: Wildland Fire Leadership Development Program (WFLDP)

The Wildland Fire Leadership Development Program is announcing the 2025 Professional Reading list! The goal of the annual reading list is to promote the reading and discussion of the books throughout the year.

The five books chosen for this year are: Surf When You Can by Brett Crozier, Man’s Search for Meaning by Viktor E. Frankl, Elephant Company by Vicki Constantine Croke, Simply Managing by Henry Mintzberg, and Chop Wood Carry Water by Joshua Metcalf.

References:

Professional Reading Program

Task Group Volunteers Needed to Update the Property Loss or Damage Report, OF 289

Date: February 5, 2025
Contact: Julie Bennett, Incident Business Committee Chair

The Incident Business Committee (IBC) is requesting volunteers for a new task group to revise the 1981 version of the Property Loss or Damage Report, OF 289 and create an incident replacement job aid. The volunteers may be recruited from within or outside the Geographic Area Incident Business Committees.

References:

IBC Memorandum 25-02

IBC Correspondence