NWCG Glossary of Wildland Fire (PMS 205)

Chemical powders that will, in very small quantities, tend to prevent other powders from caking and flocculating. Imparts free-flowing qualities to powder. Used with fire retardant chemicals.

A low expansion foam type with some bubble structure and moderate drain time, exhibiting properties of both wet and dry foam types, which is used for extinguishment, protection, and mopup.

Particulate matter emitted by a fire and larger than 10 microns in diameter with a consequently short residence time in the atmosphere.

The aerated solution created by forcing air into, or entraining air in water containing a foam concentrate by means of suitably designed equipment or by cascading it through the air at a high velocity. Foam reduces combustion by cooling, moistening and excluding oxygen. 

A layer of foam which forms an insulating and reflective barrier to heat and is used for fuel protection, suppression, and mopup.

The concentrated foaming agent as received from the manufacturer which, when added to water, creates a foam solution; use only those approved for use in wildland fire situations by the authority having jurisdiction.

The foam production process of forcing air into or entraining air in foam solution, creating a mass of bubbles.

A body of foam placed along areas to be protected from fire; also used as an anchor for indirect attack in place of hand-made fire line.

A low expansion foam type with no expansion, therefore lacking bubble structure, which is used for mopup and flame knock down.

The apparatus and techniques used to mix concentrate with water to make solution, pump and mix air and solution to make foam, and transport and apply foam. (Systems defined here include compressed air foam and nozzle aspirated.)

A term used to describe the consistency and viscosity of low expansion foam as the combination of drain time and expansion.

An additive that reduces the surface tension of water (producing wet water) causing it to spread and penetrate more effectively and which produces foam through mechanical means.

A warm, dry and strong general wind that flows down into the valleys when stable, high pressure air is forced across and then down the lee slopes of a mountain range. The descending air is warmed and dried due to adiabatic compression producing critical fire weather conditions. Locally called by various names such as Santa Ana winds, Devil winds, North winds, Mono winds, etc. 

A portable, collapsible water tank with a tubular frame. Tank capacities vary in size from 500-1500 gallons.

Food Unit staff determine the food and hydration needs of personnel assigned to the incident and plan menus, order food, provide cooking facilities, cook and serve food, maintain food service areas, and manage food security and safety.Efficient food service is especially important for extended incidents. Food Unit staff anticipate incident needs, such as the number of people who will need to be fed and whether the incident’s type, location, or complexity predicates special food needs. The unit staff supply food to meet the nutritional needs during the entire incident, including all remote locations (e.g., camps and staging areas), and supply on-site food service to operations personnel who are unable to leave their assignments. Careful planning and monitoring helps ensure food safety before and during food service operations, including the assignment, as needed, of public health professionals with expertise in environmental health and food safety.

A plant with an herbaceous (soft, rather than permanent woody) stem, that is not a grass or grasslike plant.

Landing necessitated by failure of engines, systems, or components which makes continued flight impossible and which may not result in damage.

Entering a structure of vehicle illegally by means or physical force, often characterized by prying doors and breaking windows.

Geographical area for which a fire weather forecast is specified.

An event dealing with a wildland fire originating from a country outside of the U.S., which has burned onto U.S. soil.

Variously defined for legal purposes (e.g., the State of California Public Resources Code: uncontrolled fire on lands covered wholly or in part by timber, brush, grass, grain, or other flammable vegetation). Types of fires are ground, surface, and crown.

Forestry branch concerned with prevention and damage control to forests from human actions (unauthorized fire, grazing, felling, smoke), pests and pathogens, and damage from storm, frost, and other climatic agents.

Accumulation in the forest of living or dead (mostly woody) material that is added to and rearranged by human activities such as harvest, cultural operations, and land clearing.

Indicates if the Forest Service provided assistance on an incident outside their jurisdiction.

A code used to indicate the Forest Service job accounting code for the incident. This is specific to the Forest Service, and is usually displayed as two-character prefix on the FireCode.

A code used to indicate the Forest Service override code for the incident. This is specific to the Forest Service, and is usually displayed as a four-character suffix on FireCode.

Hand held or aircraft mounted device designed to detect heat differentials and display their images on a video screen. FLIRs have thermal resolution similar to IR line scanners, but their spatial resolution is substantially less; commonly used to detect hotspots and flareups obscured by smoke, evaluate the effectiveness of firing operations, or detect areas needing mopup. 

The speed with which a fire moves in a horizontal direction across the landscape, usually expressed in chains per hour or feet per minute.

Objects that are easily susceptible to damage from head and flame and can be easily damaged or destroyed by suppression action and/or during the evidence collection process. E.g., cigarette ash.

The condition of a fire or part of a fire that has not been slowed by natural barriers or by control measures.

Cargo, not attached to a parachute, that is dropped intentionally from an aircraft in flight.

Maximum water flow rate a fire pump will attain when there are no restrictions at the pump outlet or losses due to friction or head.

Rain that freezes upon contact with objects on the ground.

A quantitative expression of the presence or absence of individuals of a species in a population; the ratio between the number of sample units that contain a species and the total number of sample units.

A designation of the kind of communications that will occur on an assigned radio frequency.

The layer of the atmosphere in which the frictional force of the earth's surface exercises an appreciable influence on winds.

Pressure loss caused by the movement of water or solution against the interior surface of fire hose, pipe, or fittings; normally measured in pressure loss per length of hose or pipe.

Water soluble substance that reduces frictional drag of solutions and dampens turbulent flow while being pumped through pipe or hose.

In meteorology, the boundary between two air masses of differing atmospheric properties.

Crystals of ice formed and deposited like dew, but at a temperature below freezing.

In the 1978 version of NFDRS, the herbaceous stage when cold temperatures kill herbaceous plants and force woody fuels into dormancy.

Any combustible material, especially petroleum-based products and wildland fuels.

A general term referring to the spatial distribution and orientation of fuel particles or pieces.

An array of fuels usually constructed with specific loading, depth, and particle size to meet experimental requirements; also, commonly used to describe the fuel composition.

Average height of surface fuels contained in the combustion zone of a spreading fire front.

A natural or manmade change in fuel characteristics which affects fire behavior so that fires burning into them can be more readily controlled.

A series of modified strips or blocks tied together to form continuous strategically located fuel breaks around land units.

Factors that make up fuels such as compactness, loading, horizontal continuity, vertical arrangement, chemical content, size and shape, and moisture content.

Group of fuels possessing common characteristics. Dead fuels are grouped according to 1-, 10-, 100-, and 1000-hour timelag, and living fuels are grouped as herbaceous (annual or perennial) or woody.