Untitled Deck Flashcards
What is Fire Behavior?
The manner in which a fire reacts to the influences of fuel, weather, and topography.
What is Fuel?
Combustible material that feeds a fire, including vegetation such as grass, leaves, ground litter, plants, shrubs, and trees.
What are the States of Matter?
The forms in which matter can exist: solid, liquid, and gas. Fire behavior is influenced by the state of matter of the fuel, as solids must be converted to gases before they can burn.
What is Pyrolysis?
The process of a solid fuel, like wood, converting to a gas or vapor due to heat. This is essential for combustion to occur.
What is the Fire Triangle?
The three elements required for fire: oxygen, heat, and fuel. Removing any one of these elements extinguishes the fire.
What is the Fire Tetrahedron?
A more modern representation of the elements of fire, adding a fourth component: chemical chain reaction to the fire triangle.
What is a Ventilation-Limited Fire?
A fire that has insufficient oxygen for efficient burning, often characterized by dark, pressurized, turbulent smoke. Opening doors or windows in such a fire can lead to a rapid increase in intensity.
What is a Fuel Bed?
The arrangement and types of fuels present, significantly impacting fire behavior. A continuous fuel bed, with brush connecting to the lower limbs of trees, allows for easy vertical fire spread.
What is Torching?
When a single tree or a small group of trees ignites and burns from the bottom up, often due to intense ground fuels.
What is a Crown Fire?
Fire spreading through the crowns of trees or shrubs, often independent of a surface fire. This is driven by intense energy and creates a strong convective column, drawing in air and increasing wind speed.
What is an Ember?
Small, burning pieces of fuel that can be carried by wind and ignite new fires far from the main fire front. The size and ability of embers to travel are influenced by the intensity of the fire and wind conditions.
What is Defensible Space?
A buffer zone around a structure, cleared of flammable vegetation to reduce the risk of ignition from wildfire.
What is Fuel Treatment?
Modifying the fuel bed, typically by reducing fuel loads and continuity, to alter fire behavior and decrease intensity and spread.
What are Aerial Fuels?
All live and dead vegetation in the forest canopy or above the surface, including tree branches, twigs, cones, snags, moss, and high brush.
What are Surface Fuels?
The combustible materials on the ground, such as leaves, needles, twigs, bark, cones, branches, grass, and downed logs.
What are Ground Fuels?
Combustible materials beneath the surface litter, including duff, roots, and decayed wood. These fuels support smoldering combustion.
What are Fine (Light) Fuels?
Small-diameter fuels, less than 1/4 inch, with a high surface area-to-volume ratio that ignite easily and burn rapidly. These fuels include grasses, leaves, and pine needles.
What are Heavy Fuels?
Large, dense fuels that include trees, logs, large branches, and stumps. These fuels burn slowly but release a lot of heat and can sustain a fire for long periods.
Aka “Coarse Fuels”)
Characteristics: Heavy fuels don’t ignite as quickly as fine fuels but can burn intensely and for longer durations, making them significant contributors to prolonged fire intensity and spread.
Examples: Fallen trees, large branches, thick logs, and tree stumps.
Data Implications for COP: Heavy fuels are important for modeling long-term fire behavior. Areas with heavy fuels can lead to persistent hot spots, even after the main fire has passed.
What are Ladder Fuels?
Vegetation that provides vertical continuity between surface fuels and the crowns of trees, allowing fire to climb easily into the canopy.
What is a Spot Fire?
A fire ignited outside the main fire perimeter by embers carried by wind. These fires can rapidly expand the fire area and pose challenges for control.
Aerial Fuels
All live and dead vegetation in the forest canopy or above surface fuel level including tree branches, twigs,
cones, snags, moss and high brush.
Airtanker
Fixed‐wing aircraft capable of dropping fire retardant.
Anchor Point
Advantageous location from which to start building a fire line.
Backfire
Fire set along the inner edge of a fireline to consume fuel in the path of an existing wildfire. Operation is
designed to change the direction of or slow down the existing wildfire by removing its fuel.
Blow Up
Sudden increase in fire intensity or rate of spread that is strong enough to prevent direct control or upset
control plans.
Brush
Collective term for vegetation dominated by shrubby, woody plants or low growing trees; usually undesirable for
livestock or timber management.
Brush Fire
Fire burning in vegetation that is predominantly shrubs, brush and scrub growth.
Burn Ban
Declared ban on outdoor burning, usually because of high‐to‐extreme fire danger.
Burn Out
Setting fire inside a control line to widen it or consume the fuel between the edge of the fire and control line.
Burning Conditions
Combined environmental factors that affect fire behavior in a specific fuel type.
Burning Period
Time of the day when fires spread most rapidly; typically from 10 a.m. to sundown.
Candle or Candling
A single tree in a very small clump of trees that is burning from the bottom up.
Chain
Unit of linear measurement equal to 66 feet; often used to describe the length of a fireline or the forward rate of spread on a fire. Eighty chains equal one mile.
Closure
Legal restriction — but not necessarily elimination — of specific activities such as smoking, camping or access to a designated area.
Complex
Two or more individual fires located in the same general area and assigned to a single incident commander or
unified command.
Confine a Fire
Least aggressive wildfire suppression strategy; typically allows the wildfire to burn itself out within established,
natural boundaries such as rocky ridges, streams or roads under prevailing conditions.
Contain a Fire
When a fire is contained, it is surrounded by a fuel break. This break can include natural barriers as well as line
constructed manually or mechanically. The fire is not extinguished at this point.
Control a Fire
When a fire is controlled, it is surrounded by control line, its forward progression has been stopped and it is not
expected to escape under foreseeable conditions. It is not completely extinguished, but it no longer poses a
direct threat to surrounding homes or property.
Creeping Fire
Fire burning on the ground with a low flame and spreading slowly.
Crowning Fire
Movement of fire through the tops of trees and shrubs, usually independent of the surface fire.
Curing
Drying and browning of herbaceous vegetation or slash.
Dead Fuels
Fuels with no living tissue, which means moisture content is governed almost entirely by atmospheric moisture
(relative humidity and precipitation), dry‐bulb temperature and solar radiation.
Debris Burning
Fire is intentionally set to clear the land or eliminate garbage and other debris.
Defensible Space
Natural or manmade area spanning at least 30 feet around a structure where combustible material has been cleared or removed, providing a barrier between you and an advancing wildfire.
Direct Attack
Any treatment of burning fuel such as wetting, smothering or chemically quenching the fire or by physically
separating burned and unburned fuel.
Dozer
Any tracked vehicle with a front‐mounted blade is used for exposing mineral soil.
Dozer Line
Fireline constructed by the front blade of a dozer.
Drip Torch
Hand‐held device used to ignite fires by dripping flaming liquid torch fuel on the materials to be burned. Torch
fuel generally is a mix of diesel and gasoline.
Drop Zone
The target area for air tankers, helitankers, and cargo dropping.
Drought Index
Number representing the difference between normal and current moisture conditions. Net
effect of evaporation, transpiration and precipitation in producing cumulative moisture depletion in deep duff or upper soil layers.
Duff
Layer of decomposing organic materials lying just below the litter layer of freshly fallen twigs, needles and leaves, and just above the bare, mineral soil.
Ecosystem
The area of land is distinguished by certain physical features, as well as its ability to sustain certain plants and animals.
Energy Release Component
Computed total heat released per unit area (British thermal units per square foot) within the fire front at the head of a moving fire. Used by fire managers to assess the potential fire behavior in forest fuels.
Engine
Any ground-level machine providing specified levels of pumping, water, and hose capacity.
Engine Crew
Firefighters assigned to a type of engine. Minimum crew make up is determined by engine type as outlined in the Fireline Handbook.
Entrapment
Situation in which crews are caught unexpectedly in a life‐threatening position with planned escape routes or safety zones compromised, likely because of fire behavior. Entrapment may or may not result in fire shelter deployment or injuries.
Escape Route
Planned route allowing firefighters safe passage to a designated safety zone. When escape routes deviate from a defined, physical path, they should be clearly flagged.
Escaped Fire
Fire that continues to spread despite initial attack fire suppression efforts. Also applies to prescribed fire that
exceeds its prescription.
Extended Attack
Suppression activity for a wildfire that has not been contained or controlled by initial attack or contingency forces. Additional firefighting resources generally are needed for extended attack.
Faller
A person who falls (cuts down) trees. Also called a sawyer or cutter.
Fell
Cut or knock down; usually refers to a tree.
Fingers of Fire
Long, narrow extensions of a fire projecting from the main body.
Fire Behavior
Manner in which a fire reacts to fuel, weather and topography.
Fire Behavior Forecast
Prediction of probable fire behavior, usually by fire behavior analysts.
Fire Break
Natural or constructed barrier used to stop or check fires that may occur or to provide a control line from which to work.
Fire Cache
Supply of fire tools and equipment assembled at a strategic point for exclusive use in fire suppression.
Fire Crew
Organized group of firefighters under the supervision of a crew leader or other designated official.
Fire Danger
Probability — based on weather, fuel moisture and other factors — of a fire occurring, and the likelihood of it spreading. Danger is categorized as low, moderate, high or extreme.
Fire Dependent Species
Plant and animal species that are dependent on fire to survive. Lodgepole pine is an example; heat from the fire opens pine cones, allowing seeds to spread and naturally reforest an area.
Fire Front
Part of a fire within which continuous flaming combustion is taking place. Unless otherwise specified, the fire
front is assumed to be the leading edge of the fire perimeter. In ground fires, the fire front may be mainly
smoldering combustion.
Fire Intensity
Amount of heat generated by a fire.
Fire Line
Linear fire barrier that is scraped or dug down to mineral soil — by hand or mechanically. More generally, the
term “on the fireline” is used to describe working a fire.
Fire Perimeter
Entire outer edge or boundary of a fire.
Fire Plow
Heavy duty plowshare or disc usually pulled behind a tractor to construct a fireline.
Fire Season
Period or periods of the year when wildfires are likely to occur, spread and affect resource values sufficient to warrant organized fire management activities.
Fire Shelter
Safety device used as a last resort by wildland firefighters who are trapped by wildfire. The small, aluminized tent provides protection by reflecting radiant heat and offering a small amount of breathable air.
Fire Triangle
Instructional aid in which the sides of a triangle are used to represent the three factors — oxygen, heat and fuel—necessary for combustion and flame production. Removal of any of the three factors ceases flame production.
Fire Weather
Weather conditions that influence fire ignition, behavior and suppression.
Fire Weather Watch
Term used by National Weather Service fire weather forecasters to notify fire managers, usually 24 to 72 hours in advance, that current and developing meteorological conditions may evolve into dangerous fire weather.
Firefighting Resources
All people and major items of equipment that can or potentially could be assigned to fires.
Flame Length
Distance between the flame tip and the midpoint of the flame depth at the base of the flame (generally the
ground surface); an indicator of fire intensity.
Flanks of a Fire
Parts of a fire’s perimeter that are roughly parallel to the main direction of spread.
