NWCG Glossary of Wildland Fire, PMS 205

Any source of heat, natural or human made, capable of igniting wildland fuels. Flaming or glowing fuel particles that can be carried naturally by wind, convection currents, or by gravity into unburned fuels.

A natural or constructed barrier used to stop or check fires that may occur, or to provide a control line from which to work.

Set of computerized FIREMODELS run during fire season at the operations coordination center on preselected locations to indicate possible fire spread from those points for that date.

A standardized code used by the federal wildland fire agencies/bureau assigned to effectively track and compile cost information for emergency suppression expenditures. The FireCode is incorporated into each agency’s accounting code structure.

Person whose principal function is fire suppression.

Qualified firefighters, together with their equipment and material, used to suppress wildland fires.

Operational area on which firefighters combat a fire.

Computerized multi-resource model that simulates the effects that naturally caused prescribed fires have on the future production of natural resources such as timber, forage, wildlife, recreation, and water.

For purposes of pay administration for hazardous duty, a fireline is defined as the area within or adjacent to the perimeter of an uncontrolled wildfire of any size in which action is being taken to control fire. Such action includes operations, which directly support control of fire (e.g. activities to extinguish the fire, ground scouting, spot fire patrolling, search and rescue operations, and backfiring).

The part of a containment or control line that is scraped or dug to mineral soil.

Specially developed coils containing explosive powder that are detonated to create a fireline through ground fuels.

The product of the available heat of combustion per unit of ground and the rate of spread of the fire, interpreted as the heat released per unit of time for each unit length of fire edge. The primary unit is Btu per second per foot (Btu/sec/ft) of fire front.

The rate of heat release per unit time per unit length of fire front. Numerically, it is the product of the heat yield, the quantity of fuel consumed in the fire front, and the rate of spread.

Firefighting Resources of California Organized for Potential Emergencies. A multi-agency coordination system designed to improve the capabilities of California's wildland fire protection agencies. Its purpose is to provide more efficient resources allocation and utilization, particularly in multiple or large fire situations during critical burning conditions. 

Person who starts a fire, usually deliberately and maliciously.

Starting a fire, usually deliberately and maliciously.

The act of setting fire to unburned fuels located between the control line and main fire in burning out operations.

Any method or pattern of igniting a wildland area to consume the fuel in a prescribed pattern. E.g., heading or backing fire, spot fire, strip-head fire, and ring fire.

Emergency care or treatment given to an ill or injured person before regular medical care can be obtained. First aid is generally provided by someone other than a physician. On incidents, most first aid is provided in the field or camp by medical unit personnel such as Emergency Medical Technicians (EMT).

The first combustible material ignited beyond the components of the ignition source itself.

The first name of the resource as it appears on a government issued ID.

The effects that concern the direct or immediate consequences of fire, such as biomass consumption, crown scorch, bole damage, and smoke production. First order effects form an important basis for predicting secondary effects such as tree regeneration, plant succession, and changes in site productivity, but these involve interaction with many other non-fire variables. 

A burn which causes only pain, redness, and swelling.

Firefighters initially attacking a fire, usually the first to arrive at the fire scene.

A descriptor of a human resource's physical work capacity

Geographical position determined by visual reference to the surface, by reference to one or more radio navigational aids, by celestial plotting, or by any other navigational device.

A device mounted inside or directly underneath an aircraft which can contain water or retardant for dropping onto a fire.

Light given off by burning gasses during the combustion process.

A mass of gas undergoing rapid combustion, generally accompanied by evolution of sensible heat and incandescence.

Angle between the flame at the leading edge of the fire front and the ground surface, expressed in degrees.

The depth of the fire front.

The average maximum vertical extension of flames at the leading edge of the fire front. Occasional flashes that rise above the general level of flames are not considered. This distance is less than the flame length if flames are tilted due to wind or slope. 

The 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.

Device for throwing a stream of flaming liquid, used to facilitate rapid ignition during burn out operations on a wildfire or during a prescribed fire operation.

Luminous oxidation of gases evolved from the rapid decomposition of fuel. This phase follows the pre-ignition phase and precedes the smoldering combustion phase, which has a much slower combustion rate. Water vapor, soot, and tar comprise the visible smoke. Relatively efficient combustion produces minimal soot and tar, resulting in white smoke; high moisture content also produces white smoke. 

That zone of a moving fire where the combustion is primarily flaming. Behind this flaming zone combustion is primarily glowing or involves the burning out of larger fuels (greater than about 3 inches in diameter). Light fuels typically have a shallow flaming front, whereas heavy fuels have a deeper front.

That phase of a fire where the fuel is ignited and consumed by flaming combustion.

The relative ease with which fuels ignite and burn regardless of the quantity of the fuels. Preferred to "inflammability."

Easily ignitable and capable of burning and producing flames.

A liquid generally with a flash point below 140F (60C) and a vapor pressure that does not exceed 40 PSI at 100F (37.8C).

A firing technique consisting of treating an area with lines of fire set into the wind which burn outward at right angles to the wind.

Attacking a fire by working along the flanks either simultaneously or successively from a less active or anchor point and endeavoring to connect two lines at the head.

The parts of a fire’s perimeter that are roughly parallel to the main direction of fire spread.

The parts of a fire's perimeter that are roughly parallel to the main direction of spread.

Fire suppression tool, sometimes improvised, used in direct attack for smothering out flames along a fire edge; may consist merely of a green pine bough or wet sacking, or be a manufactured tool such as a flap of belting fabric fastened to a long handle.

Any sudden acceleration in rate of spread or intensification of the fire. Unlike blowup, a flare-up is of relatively short duration and does not radically change existing control plans.

Highly combustible fine fuels such as grass, leaves, draped pine needles, fern, tree moss and some kinds of slash, which ignite readily and are consumed rapidly when dry.

Lowest temperature at which the vapor of a combustible liquid can be made to ignite in air.

Rapid combustion and/or explosion of unburned gases trapped at some distance from the main fire front. Usually occurs only in poorly ventilated topography.

Stage of a fire at which all surfaces and objects within a space have been heated to their ignition temperature, and flame breaks out almost at once over the surface of all objects within the space.