Wildfire Rank

The BC Wildfire Service uses a ranking scale from 1 to 6 to quickly describe fire behaviour based on a set of visual indicators.

Fire Ranks 1 through 6 are illustrated, left-to-right, in this banner.

Fire rank should not be confused with fire intensity class, as described in the Canadian Forest Fire Behaviour Prediction System. The fire intensity classes, from 1 to 6, are each assigned a range of fire intensity values in kilowatts per meter.

Definitions (adapted from the Canadian Interagency Forest Fire Centre (CIFFC) Glossary of Forest Fire Management Terms):

  • Ground fire: a fire that burns in the ground fuel layer (i.e. combustible material below the litter layer of the forest floor).
  • Surface fire: a fire that burns in the surface fuel layer on the forest floor, but below the tree crowns.
  • Crown fire: a fire that advances through the crown fuel layer i.e. tree tops, usually in conjunction with the surface fire.
  • Candling or Torching: a single tree or a small clump of trees is said to “candle” or “torch” when its foliage ignites and flares up, usually from bottom to top.

A rank 1 wildfire is illustrated.Characteristics

  • Smouldering ground fire  
  • No open flame
  • White smoke
  • Slow (i.e. creeping) rate of fire spread

Examples of firefighting tactics

  • Direct attack with ground crews using handtools and water delivery systems (i.e. pumps and hose).

A rank 2 wildfire is illustrated.Characteristics

  • Surface fire
  • Visible, open flame
  • Unorganised or inconsistent flame front
  • Slow rate of spread

Examples of firefighting tactics

  • Direct attack with ground crews using handtools, water delivery systems, or heavy equipment;
  • Hand constructed control lines and lines that have been cleared of combustible material will likely be successful.

A rank 3 wildfire is illustrated.Characteristics

  • Organised flame front – fire progressing in organised manner
  • Occasional candling may be observed along the perimeter and/or within the fire
  • Moderate rate of spread

Examples of firefighting tactics

  • Hand constructed control lines alone are likely to be challenged
  • Ground crews conducting direct attack may require air support from fixed-wing air tankers, skimmers or helicopters conducting bucketing or tanking operations
  • Control lines constructed by heavy equipment will generally be effective.

A rank 4 wildfire is illustrated.Characteristics

  • Grey to black smoke
  • Organised surface flame front
  • Moderate to fast rate of spread on the ground
  • Short aerial bursts through the forest canopy
  • Short-range spotting

Examples of firefighting tactics

  • Ground operations may not be successful at the head of the fire
  • Indirect tactics may be required to bring the head of the fire under control
  • Parallel attack may be used along the flanks of the fire to direct the head into favourable ground or fuels
  • Air operations may be required to support ground personnel

A rank 5 wildfire is illustrated.Characteristics

  • Black to copper smoke
  • Organised crown fire front
  • Moderate to long-range spotting and independent spot fire growth

Examples of firefighting tactics

The limited options available include indirect attack and planned ignitions to remove fuel in the path of this type of fire behaviour. Ground operations are often restricted to fighting the least active sections of the fire or conducting ground ignition operations from secure control lines with readily available escape routes and safety zones.

A rank 6 wildfire is illustrated.Characteristics

  • Organised crown fire front
  • Long-range spotting and independent spot fire growth
  • Possible fireballs and whirls
  • Violent fire behaviour probable
  • A dominant smoke column may develop which influences fire behaviour

Fire suppression strategy

Firefighting under these conditions is extremely dangerous. Suppression efforts will be well away from active fire behaviour and may include preparing structure protection measures or conducting indirect large-scale ignition operations in an attempt to steer the fire. Often, the safest and most prudent strategy is to pull resources back to safe areas, ensure that personnel and the general public are safe, and wait for fire behaviour to lessen before re-engaging in fire suppression operations.