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CFFDRS System Overview

  1. Introduction
  2. Use of English Units
  3. Wind Observations
  4. Fire Intensity Measures

Introduction

The Canadian Forest Fire Danger Rating System, as shown in these flow charts, is a comprehensive system of tools designed to evaluate environmental factors that influence the ignition, spread, and behavior of wildland fire. Additional detail about the system and its subsystems can be learned from an introductory certificate online course and direct access to the YouTube videos that support it:

CFFDRS Components

The system had its origins from early efforts dating to the 1920s and the development of the Tracer Index, a forerunner of the Fine Fuel Moisture Code (FFMC).

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The Fire Weather Index System. This process flow chart outlines the system inputs, as well as the array of output codes and indices

Fire Weather Index (FWI) System Process Flow Chart

The FWI system was developed and introduced across Canada in 1970. Due to its simplicity in terms of data required and outputs produced, it is used both globally and within many regions around the world.

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The Fire Weather Index System. This process flow chart outlines the system inputs, as well as the array of output codes and indices.

 

Fire Behavior Prediction (FBP) System Process Flow Chart

The FBP system tools were released in interim form in 1984, with a more formal introduction in 1992, and revisions in 2008.

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The Fire Behavior Prediction System. This process flow chart outlines the system inputs, as well as the array of primary fire behavior and secondary fire growth characteristics.

Additional systems for fuel moisture (e.g. hourly FFMC and Grass Fuel Moisture) and ignition have followed.

There are several important distinctions for NFDRS and NFBPS users.

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Use of English Units

All the CFFDRS tools and references produced by the Canadian and Provincial governments, as well as applications produced internationally, use the metric system for all measured values. For the most part, measures referenced here are in English units to facilitate utility and use in the United States.

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Wind Observations

This table provides a quick reference to aid conversion between 10m, 20ft, unsheltered Eye Level (EL Op) observations, and Forecast/Airport winds. 

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Open Windspeed Chart: Use only 10m for effective windspeed

CFFDRS weather observations, provided to the system for both FWI and FBP calculations, generally conform to familiar fire weather standards. These standards can be reviewed in the weather guide table referenced above. However, wind observation standards conform to the international 10m height as opposed to the NFDRS 20-foot height standard.

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This depiction highlights the difference in height standard among fixed and handheld wind sensors used in fire management applications.

(Andrews, 2012)

CFFDRS models and tools do not expressly apply relationships between the standard 10m wind measurements and others that U.S. users may be familiar with. Both 20-foot and eye level winds are commonly referenced and reported from U.S. RAWS observing locations and from the fireline.

Further, wind speeds reported from Airport ASOS (Automated Surface Observing System) and provided in National Weather Service forecasts generally report higher wind speed, where surrounding terrain is flat with little variation in vegetation height or structural interference, and is highly correlated with forecast wind speed provided in the National Digital Forecast Database (Lawson and Armitage, 2008).

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Surrounding terrain and surface characteristics affect the windspeed measured by sensors. Compares the speeds measured at generally flat/smooth surfaces around airport sensors, more variable and rougher terrain found in forest RAWS settings, and the highly modified results obtained in urban settings.

(Lawson & Armitage, 2008)

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Fire Intensity Measures

A major adaptation in U.S. tools and references, with uncertain validity, is the use of flame length for fire intensity outputs in the Fire Behavior Tables. FBP outputs (kW/m) were converted to BTU/ft/sec using standard conversions and then to flame length using the formula:

Flame Length = .45*"BTU/Ft/Sec"^.46

This table identifies the CFFBP Fire Intensity thresholds in kW/m and the corresponding values in English units (BTU/ft/sec) and flame length in feet. These thresholds are consistent with commonly held flame length thresholds for fire safety interpretations in the U.S. system.

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The Fire Intensity Class Conversion Table shows the relationship among English and metric representations of fireline intensity at key threshold levels.

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NWCG Latest Announcements

Updated NWCG Standards for Fire Unmanned Aircraft Systems Operations, PMS 515

Date: April 23, 2025
Questions?  Please contact:
Interagency Fire Unmanned Aircraft Systems Subcommittee

The NWCG Standards for Fire Unmanned Aircraft Systems Operations, PMS 515 standardizes processes and procedures for the interagency use of Unmanned Aircraft Systems (UAS), including pilot inspections and approvals. This updated publication provides the aviation community with standards to ensure UAS are used safely, effectively, and efficiently in support of fire management goals and objectives.

References:

NWCG Standards for Fire Unmanned Aircraft Systems Operations, PMS 515

NWCG National Interagency Aviation Committee

ETC Bulletin 25-001: Retrofitted Hot/Cold Beverage Kits - 2025 Field Season

Date: April 16, 2025
Questions?  Please contact:
Equipment Technology Committee

Due to spout failures and the associated risk of burn injuries, manufacturers have retrofitted the Hot/Cold Beverage Kits using a heat-shrinking band to secure the black spout at the insertion site. The updated kits feature a fluorescent label on each full kit assembly for easy identification. Catering units are encouraged to confirm the clear heat-shrinking bands are intact around each spout before filling.

ETC Bulletin 24-001 regarding Hot/Cold Beverage Kits has been archived and replaced by ETC Bulletin 25-001 for the 2025 season.

References:

NWCG Alerts

ETC-EB-25-001 Retrofitted Hot/Cold Beverage Kits

NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212, and Next Generation Position Task Book for Basic Faller Are Now Available

Date: April 14, 2025
Questions?  Please contact:
Hazard Tree and Tree Felling Subcommittee

The updated NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212, and NWCG Position Task Book for Basic Faller (FAL3), PMS 311-19 are now available.

The NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212 includes position standards designed to be used in conjunction with the Next Generation Position Task Book (Next Gen PTB). The Next Gen PTB for Basic Faller (FAL3) includes an evaluation guide with suggested rating elements to consider when assessing trainees.

References:

NWCG Standards For Wildland Fire Chainsaw Operations, PMS 212

NWCG Position Task Book for Basic Faller (FAL3), PMS 311-119

NWCG Basic Faller (FAL3)

RMC Memo 25-01: Summary of Updates to Safety Officer Positions

Date: April 9, 2025
Questions?  Please contact:
RMC Member Eric Fransted

The Risk Management Committee (RMC) serves as the position steward for all Safety Officer incident positions and continues to improve position standards, training, and naming conventions. The implementation of Complex Incident Management (CIM) required changes to position titles. RMC collaborated with the NWCG Incident Position Standards Committee (IPSC) to propose and implement these updates. 

References:

RMC Memo 25-01: Summary of Updates to Safety Officer Positions 

NWCG Position Catalog