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BLM Wyoming Wildland Fire Glossary

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Air attack - The deployment of fixed-wing or rotary aircraft on a wildland fire to drop retardant or extinguishing agents, as well as shuttle and deploy crews and supplies, or to perform aerial reconnaissance of the overall fire situation.

Air tanker - Fixed-wing aircraft certified by the Federal Aviation Administration as being capable of transport and delivery of fire-retardant solutions.

Backfire - A fire set along the inner edge of a fire line to consume the fuel in the path of a wildfire and/or change the direction of force of the fire’s convection column.

Bambi Bucket® - A collapsible bucket slung below a helicopter. Used to dip water from a variety of sources for fire suppression.

Blackline - Pre-burning of fuels adjacent to a control line before igniting a prescribed burn. Blacklining is usually done in heavy fuels adjacent to a control line during periods of low fire danger to reduce heat on holding crews and lessen chances for spotting across control lines. In fire suppression, a blackline denotes a condition where there is no unburned material between the fire line and the fire edge.

Blow-up - A sudden increase in fire intensity, or a rate of spread strong enough to prevent direct control or upset control plans. Blow-ups are often accompanied by violent convection and may have other characteristics of a fire storm (see flare-up).

Brush fire - A fire burning in vegetation that is predominantly composed of shrubs, brush, and scrub growth.

Burning ban - A declared ban on open air burning within a specified area, usually due to sustained high fire danger.

Burn out - Setting fire inside a control line to consume fuel between the edge of the fire and the control line. This is done in conjunction with construction of the control line.

Burning period - The time of day when fires spread most rapidly. Typically this is from 10 a.m. to sundown.

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Closed area - An area in which specified activities or entry are temporarily restricted to reduce risk of human-caused fires.

Closure - Legal restrictions, but not necessarily elimination, of specified activities such as smoking, camping, or entry that might cause fires in a given area.

Complex - Two or more incidents located in the same general area, assigned to a single incident commander or unified command.

Contain a fire – The establishment of a fuel break around a fire. This break may include natural barriers or a manually and/or mechanically constructed line.

Control a fire - The complete extinguishment of a fire, including spot fires. Fire line has been strengthened so that flare-ups from within the perimeter of the fire will not break through this line.

Control line - An inclusive term for all constructed or natural barriers and treated fire edges used to contain a fire.

Crew - A group usually consisting of 16-21 firefighters.

Crown fire (crowning) - The movement of fire through the crowns of trees or shrubs more or less independently of the surface fire.

Creeping fire - A fire burning on the ground with small flames spreading slowly.

Defensible space - An area, typically a width of 30 feet or more, between an improved property and a potential wildfire where the combustibles have been removed and modified.

Direct attack - Any treatment applied directly to burning fuels such as wetting, smothering, or chemically quenching the fire or by physically separating the burning from unburned fuel.

Dozer - Any tracked vehicle with a front-mounted blade used for exposing mineral soil.

Dozer line - A fire line constructed by the front blade of a dozer.

Engine - Any ground vehicle providing specified levels of pumping, water, and hose capacity.

Extreme fire behavior - “Extreme” implies a level of fire behavior that ordinarily precludes methods of direct control action. One or more of the following is usually involved: high rate of spread, prolific crowning and/or spotting, presence of fire whirls, and strong convection column. Predictability is difficult because such fires often exercise some degree of influence on their environment and behave erratically, sometimes dangerously.

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Fire behavior - The manner in which a fire reacts to the influences of fuel, weather, and topography.

Fire behavior forecast - Prediction of probable fire behavior, usually prepared by a fire behavior officer in support of fire suppression or prescribed burning operations.

Fire behavior specialist - A person responsible to the planning section chief for establishing a weather data collection system and for developing fire behavior predictions based on fire history, fuel, weather, and topography.

Fire front - The 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 danger - The probability based on weather, fuel moisture, and other factors of a fire occurring and the likelihood of it spreading. The danger is described as being low, moderate, high, very high, or extreme.

Fire intensity - A general term relating to the heat energy released by a fire.

Fire Management Plan (FMP) - A strategic plan relating to the management of wildland and prescribed fires. The plan is supplemented by operational procedures such as preparedness plans, preplanned dispatch plans, prescribed fire plans, and prevention plans.

Fire line - A line to break up fire fuels. Also known as a control line, a fire line is scraped or dug, by hand or mechanically, into mineral soil.

Fire perimeter - The entire outer edge of the fire or the length of the outer circumference of the fire.

Fire retardant - Any substance except plain water that by chemical or physical action reduces flammability of fuels or slows their rate of combustion.

Fire season - The time of year during which fires are likely to occur, spread, and cause sufficient damage to warrant control. The fire season is dependent on weather conditions.

Fire severity - A term used to describe how damaging a fire is to a certain site. Severity is measured by the amount of soil damage caused by a fire.

Fire shelter - An aluminized tent offering protection by means of reflecting radiant heat and providing a volume of breathable air in a fire entrapment situation. Fire shelters should be deployed only in life-threatening situations as a measure of last resort.

Fire spotting - A fire is “spotting” when it spreads as a result of sparks or embers carried ahead of the main fire by the wind and starts new fires.

Flare-up - Any sudden acceleration of fire spread or intensification of a fire. Unlike a blow-up, a flare-up lasts a relatively short time and does not radically change control plans.

Fuel type - Refers to the type of vegetation in which a fire is burning. Used in predicting fire behavior and determining effects a fire may have in an area.

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Hand line - Fire line constructed with hand tools.

Helitack crew - A crew of firefighters specially trained and certified in the tactical and logistical use of helicopters for fire suppression.

Hotshot crew - An organized crew of highly trained and experienced firefighters used primarily to build fire lines by hand.

Hotspot - A particularly active part of a fire.

Hotspotting - Reducing or stopping the spread of fire at points of particularly rapid rate of spread or special threat. Hotspotting is generally the first step in prompt control, with an emphasis on first priorities.

Incident commander - Individual responsible for the management of all incident operations at the incident site.

Indirect attack - Constructing a fire line some distance from the fire perimeter.

Initial attack - The actions taken by the first resources to arrive at a wildfire to protect lives and property, as well as prevent further extension of the fire.

Lead plane - Aircraft with pilot used to make trial runs over the target area to check wind, smoke conditions, and topography, and to lead air tankers to targets and supervise their drops.

Mop-up - To make a fire safe or reduce residual smoke after the fire has been controlled. This is done by extinguishing or removing burning material along or near the control line, felling snags, or moving logs so they won't roll downhill.

Mosaic - The patchwork pattern left by a fire on a landscape.

National Interagency Fire Center (NIFC) - A facility located in Boise, Idaho, jointly operated by several Federal agencies. NIFC coordinates fire operations, gives logistical support, and provides weather-forecasting services in support of fire management operations throughout the United States. 

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Preparedness - Activities that lead to a safe, efficient, and cost-effective fire management program through appropriate planning and coordination. This includes hiring, training, equipment, and equipment readiness.

Prescribed fire - Any fire ignited by management actions under certain predetermined conditions to meet specific objectives related to hazardous fuels management or habitat improvement. Prior to ignition, a prescribed fire plan must be written and approved; the plan must also meet requirements under the National Environmental Policy Act (NEPA).

Prescription - Measurable criteria that guide selection of appropriate management responses and actions under which prescribed fire will be ignited. Prescription criteria may include safety, economic, public health, environmental, geographic, administrative, social, or legal considerations.

Rate of spread - The speed at which a fire extends its perimeter. Usually it is expressed in chains or feet per second for a specific period in the fire’s history.

RAWS - Acronym for Remote Automatic Weather Station. These stations take weather readings every hour and are recorded for use by fire managers.

Red flag warning – A forecasting term that indicates an ongoing or imminent critical fire weather pattern. Such weather conditions are right for fast fire spreads, as well as high intensity if a fire starts.

Resources - 1) People and equipment used to manage a fire. 2) The natural resources of an area (timber, grass, watersheds, recreational values, and wildlife habitats).

Running - Behavior of a fire that is spreading rapidly, usually with a well-defined head.

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Safety zone - An area cleared of flammable materials used for escape in the event the line is outflanked or in case a spot fire causes fuels outside the control line to render the line unsafe.

Scratch line - An unfinished preliminary fire line hastily established or built as an emergency measure to check the spread of fire.

Slop-over - A fire edge that crosses a control line or natural barrier intended to confine the fire. Also called a breakover.

Smokejumper - A specifically trained and certified firefighter who travels to wildland fires in remote areas by aircraft and parachutes to the fire.

Spark arrester - A device installed in a chimney, flue, or exhaust pipe to stop the emission of sparks and burning fragments.

Spot fire - Fire ignited outside the perimeter of the main fire by flying sparks or embers.

Staging area - An area near an incident where resources can be placed while awaiting a tactical assignment.

Strike team - A group of same kind and type of like resources with a common leader and common communication team (e.g. Five Type 6 engines).

Temporary flight restriction (TFR) - A restriction requested by an agency and put into effect by the Federal Aviation Administration in the vicinity of an incident. The TFR restricts the operation of nonessential aircraft in the airspace around that incident.

Torching - The burning of the foliage of a single tree (or a small group of trees) from the bottom up.

Type - Refers to resource capability. A type 1 resource provides a greater overall capability due to power, size, capacity, etc., than would be found in a Type 2 resource. Resource typing provides managers with additional information in selecting the best resource for the task.

Urban interface - Any area where wildland fuels threaten to ignite homes and structures.

Wildland fire - Any nonstructure fire, other than prescribed fire, that occurs in the wildland.


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