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Fire Danger Background

  1. General References
  2. NFDRS Version Comparison

General References

Fire Danger ratings are an effective part of daily risk rating and operational preparedness for fire management agencies across the world. Chapter 10 – Preparedness of the Interagency Standards for Fire and Fire Aviation Operations outlines processes and resources applied in the development of standard Fire Danger Operating Plans in the United States.

Included in Fire Danger Operating Plans are:

  • Specification of fire danger ratings.
  • Identification of climatological thresholds for administrative purposes. Default thresholds include the 90th and 97th percentile values for key indices in the applied system. The Bureau of Land Management (Department of Interior) uses the 80th and 95th percentiles instead.
  • Communication of those danger ratings, including both internal and external forms.

Some valuable links:

A variety of fire weather systems are applied in danger rating around the United States. There are primarily two systems used in fire danger operating plans.

U.S. National Fire Danger Rating System (NFDRS):

First introduced in 1964, NFDRS has been updated in 1972, 1978, 1988, and now 2016 to integrate newer science and improved processing. This guide will compare important aspects of the 1978, 1988, and 2016 versions, detail important outputs, and describe primary components and indices. More information about the system and the latest update to it can be found at:

NFDRS Information Page

NWCG Fire Danger Subcommittee Website

The Canadian Forest Fire Danger Rating System (CFFDRS) Fire Weather Index (FWI) System

CFFDRS was introduced in Canada in 1970. Implemented in Alaska and the lake states of Michigan,
Minnesota, and Wisconsin in the early 1990s. Details about CFFDRS are included a separate section of this guide. The following websites provide data access:

Other tools, formulations, and applications are used locally across the country. Some examples are highlighted later, in the  Fire Danger References Section.

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NFDRS Structure

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Structure and Process Flow of the 2016 National Fire Danger Rating System.

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NWCG Latest Announcements

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

Date: June 12, 2025
Questions?  Please contact:
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. 
If your question is not answered there, you can 
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
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