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NWCG Glossary of Wildland Fire, PMS 205

Overview

The NWCG Glossary of Wildland Fire provides an extensive listing of approved terms and definitions used by the NWCG community. It contains terms commonly used by NWCG in the areas of wildland fire and incident management and is not intended to list all terms used by NWCG groups and member agencies. The NWCG has directed that all committee and subgroup product glossaries be contained within the NWCG Glossary of Wildland Fire to maintain definition consistency and clarity among documents.

Comments, questions, and recommendations shall be submitted to the appropriate agency program manager assigned to the Data Standards and Terminology Board (DSTB). 

NWCG Glossary of Wildland Fire, PMS 205  (Quick View)

EDG Explorer is a database platform used for managing NWCG Glossary terms.  The following table is a quick view of the terms found in EDG. More detailed information such as rules, documentation, and term relationships may be viewed in EDG Explorer.  

Note: If the NWCG Glossary of Wildland Fire is not displaying below please report it to NWCG Webmaster

Title Steward Status Definition
center firing FUSC Fire Use Subcommittee Approved

Method of broadcast burning in which fire is ignited in the center of the area to create a strong draft; additional fires are then ignited progressively nearer the outer control lines (sometimes in one step) as indraft increases so as to draw the flames and smoke toward the center. 

center location NCSC National Coordination System Committee Approved

The city and state pairing for the dispatch center location

centrifugal pump ETC Equipment Technology Committee Approved

Pump which expels water by centrifugal force through the ports of a circular impeller rotating at high speed. With this type of pump, the discharge line may be shut off while the pump is running without damaging the pump or hose.

certifying official IPSC Incident and Position Standards Committee Approved

The agency official at the home unit who is responsible for authorizing and granting position certification per agency policy. The agency official is responsible for completing the agency certification block located on the inside front cover of a Position Task Book. 

chain IOSC Incident Operations Subcommittee Approved

Unit of measure in land survey, equal to 66 feet (20 M) (80 chains equal 1 mile). Commonly used to report fire perimeters and other fireline distances, this unit is popular in fire management because of its convenience in calculating acreage (e.g., 10 square chains equal one acre). 

chain lightning FWS Fire Weather Subcommittee Approved

Lightning in a long zigzag or apparently broken line.

chain of command NIMSIC National Incident Management System Integration Committee Approved

The orderly line of authority within the rank of incident management organizations.

char (byproduct) WFISC Wildland Fire Investigation Subcommittee Approved

Carbonaceous material formed by incomplete combustion of an organic material, most commonly wood; remains of burned materials.

char (fire simulation) WFISC Wildland Fire Investigation Subcommittee Approved

In fire simulation, a darkened area within the fire perimeter; usually indicates fire has already passed through; usually created by an opaque material blocking out a selected portion of basic scene illumination.

char height FUSC Fire Use Subcommittee Approved

The vertical distance above ground scorched or blackened on a tree bole.

charged line ETC Equipment Technology Committee Approved

Hose filled with water under pressure and ready to use.

chase truck ETC Equipment Technology Committee Approved

Vehicle that carries crew gear, supplies, and operational equipment for initial/extended attack.

check line IOSC Incident Operations Subcommittee Approved

A temporary fireline constructed at right angles to the control line and used to hold a backfire in check as a means of regulating the heat or intensity of the backfire.

check valve ETC Equipment Technology Committee Approved

A valve that permits flow of liquid through a hose or pipe in one direction but prevents a return flow. Uses include the prevention of backflow on uphill hose lays, loss of prime with centrifugal pumps and chemical contamination in fire chemical mixing systems. 

check-in NIMSIC National Incident Management System Integration Committee Approved

The process whereby resources first report to an incident. Check-in locations include incident command post (ICP), base or camps, staging areas, helibases, or direct to a tactical assignment. All responders, regardless of agency affiliation, report in to receive an assignment.

Chemical

A compound or substance that has been purified or prepared.

chevron burn FUSC Fire Use Subcommittee Approved

Burning technique in which lines of fire are started simultaneously from the apex of a ridge point, and progress downhill, maintaining position along the contour; used in hilly areas to ignite ridge points or ridge ends.

Chief NIMSIC National Incident Management System Integration Committee Approved

The ICS title for individuals responsible for the management of functional sections: Operations, Planning, Logistics, and Finance/Administration.

chief of party IBC Incident Business Committee Approved

The chief of party is responsible to the sending unit dispatcher until destination is reached. Chief of party is responsible for all traveling personnel assigned on the manifest list.

circumstantial evidence WFISC Wildland Fire Investigation Subcommittee Approved

Testimony or information not based on actual personal knowledge or observation, but dependent on inference of other facts or experience. For example, testimony that defendant's cigarette lighter was found in ashes of a fire.

cirrus FWS Fire Weather Subcommittee Approved

A form of high cloud, composed of ice crystals, which seldom obscures the sun.

claim IBC Incident Business Committee Approved

A written demand for a specific amount of money or other objects of value, other than ordinary obligations incurred for services, supplies, or things.

claimant IBC Incident Business Committee Approved

An individual, partnership, association, corporation, country, the federal government, state, or other political subdivision asserting a right, demand, or claim against another entity.

Class A foam ETC Equipment Technology Committee Approved

Foam intended for use on Class A or woody fuels; made from hydrocarbon-based surfactant, therefore lacking the strong filming properties of Class B foam, but possessing excellent wetting properties.

Class B foam ETC Equipment Technology Committee Approved

Foam designed for use on Class B or flammable liquid fires; made from fluorocarbon-based surfactants, therefore capable of strong filming action, but incapable of efficient wetting of Class A fuels.

Class I Areas (air quality) FUSC Fire Use Subcommittee Approved

Geographic areas designed by the Clean Air Act subject to the most stringent restrictions on allowable increment of air quality deterioration. Class I areas include Forest Service wildernesses and nation memorial parks over 5,000 acres, National Parks exceeding 6,000 acres, international parks, as well as other designated lands. 

Class II Areas (air quality) FUSC Fire Use Subcommittee Approved

All areas of the country not designated Class I, including everything from non-Class I areas to urban areas. A greater amount of air pollution can be added to these areas than Class I.

Classroom Training Approved

An event dealing with a scheduled activity in a classroom setting or other controlled environment that provides instruction so as to make attendees fit or qualified for incident support activities.

Clean Air Act RMC Risk Management Committee Approved

A federal law enacted to ensure that air quality standards are attained and maintained. Initially passed by Congress in 1963, it has been amended several times.

clear text NIMSIC National Incident Management System Integration Committee Approved

Communication that does not use codes.

climate FWS Fire Weather Subcommittee Approved

The prevalent or characteristic meteorological conditions of any place or region, and their extremes.

climate class FDSC Fire Danger Subcommittee Approved

In NFDRS, one of four classifications of general climate of an area.

climatological breakpoint FDSC Fire Danger Subcommittee Approved

Points on the cumulative distribution of one fire weather/fire danger index without regard to associated fire occurrence/business.

clock method NIAC National Interagency Aviation Committee Approved

Means of establishing a flight path to a target on a fire by referring to clock directions from the aircraft's present location, with the nose of the aircraft pointing at 12:00.

closed area FUSC Fire Use Subcommittee Approved

An area in which specified activities or entry are temporarily restricted to reduce risk of human-caused fires or to mitigate the risk to human health or safety by potential or on-going wildland fires.

closure CEPC Communication, Education, and Prevention Committee Approved

An administrative action limiting or prohibiting access to a specific geographic or jurisdictional area for the purposes of reducing wildfire or the risk it poses to life, property, and/or resources. Example of use: "Pursuant to 36 C.F.R. 261.50 (a) and (b), it is hereby ordered that the prohibitions hereinafter set forth apply to the general forest area of the Ozark-St. Francis National Forests until further notice."

Closures

Not open

cloud FWS Fire Weather Subcommittee Approved

A visible cluster of minute water/ice particles in the atmosphere.

cloudy FWS Fire Weather Subcommittee Approved

Adjective class representing the degree to which the sky is obscured by clouds. In weather forecast terminology, expected cloud cover of about 0.7 or more warrants use of this term. In the National Fire Danger Rating System, 0.6 or more cloud cover is termed "cloudy."

co-op fire IBC Incident Business Committee Approved

Refers to federal, state, and local cooperative fire programs.

cold front FWS Fire Weather Subcommittee Approved

The leading edge of a relatively cold air mass which displaces warmer air, causing it to rise. If the lifted air contains enough moisture, cloudiness, precipitation and even thunderstorms may result. As fronts move through a region, in the Northern Hemisphere, the winds at a given location will experience a marked shift in direction. Ahead of an approaching cold front, winds will usually shift gradually from southeast to south, and on to southwest. As a cold front passes, winds shift rapidly to west, then northwest. Typical cold front windspeeds range between 15 and 30 mph but can be much higher. 

cold line IOSC Incident Operations Subcommittee Approved

Fireline that has been controlled. The fire has been mopped up for a safe distance inside the line and can be considered safe to leave unattended.

cold trailing IOSC Incident Operations Subcommittee Approved

A method of controlling a partly dead fire edge by carefully inspecting and feeling with the hand for heat to detect any fire, digging out every live spot, and trenching any live edge.

collective control NIAC National Interagency Aviation Committee Approved

Controls the pitch angle of the main (helicopter) rotor blades. Used as primary altitude control.

colonizer FUSC Fire Use Subcommittee Approved

Species of vegetation that establish on a burned (or otherwise denuded) site from seed.

combination nozzle ETC Equipment Technology Committee Approved

A nozzle is designed to provide either a solid stream or a fixed spray pattern suitable for applying water, wet water or foam solution.

combination nozzle tip ETC Equipment Technology Committee Approved

Two attached straight stream nozzle tips of different orifice size used to increase or restrict water flow.

combustion FWS Fire Weather Subcommittee Approved

The rapid oxidation of fuel in which heat and usually flame are produced. Combustion can be divided into four phases: preignition, flaming, smoldering, and glowing.

combustion efficiency FWS Fire Weather Subcommittee Approved

The relative amount of time a fire burns in the flaming phase of combustion, as compared to smoldering combustion. A ratio of the amount of fuel that is consumed in flaming combustion compared to the amount of fuel consumed during the smoldering phase, in which more of the fuel material is emitted as smoke particles because it is not turned into carbon dioxide and water. 

combustion period FWS Fire Weather Subcommittee Approved

Total time required for a specified fuel component to be completely consumed.

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NWCG Latest Announcements

NWCG Standards for Helicopter Operations, PMS 510

Date: May 25, 2023
Contact: Interagency Helicopter Operations Subcommittee (IHOPS)


The 2023 revision of the NWCG Standards for Helicopter Operations (NSHO), PMS 510, establishes the standards by which helicopter operations are to be conducted under the exclusive direction and operational control of federal, state, and local agencies in the accomplishment of interagency fire suppression and natural resource aviation management.

References:

NWCG Standards for Mitigation in the Wildland Urban Interface, PMS 052

Date: May 25, 2023
Contact: Wildland Urban Interface Mitigation Committee (WUIMC)

The NWCG Standards for Mitigation in the Wildland Urban Interface, PMS 052, establishes the standards for understanding and implementation of concepts, issues, and best practices to increase community fire adaptation. This publication is designed to: support common understanding, encourage use of consistent and proven local risk reduction efforts, increase awareness and implementation of mitigation best practices, techniques, tactics, and strategies, and improve community and structure survivability as the result of pre-wildfire mitigation actions.

References:

Incident Performance and Training Modernization (IPTM) Contract Awarded

Date: May 17, 2023
Contact: Incident Performance and Training Modernization (IPTM)

Today, the National Wildfire Coordinating Group (NWCG) announced the award of a contract as part of an ongoing effort to improve wildland fire management through Incident Performance and Training Modernization. The contract will assist NWCG with building incident position standards, developing an integrated performance-based training system, and aid in modernizing training materials and operational tools to meet NWCG’s mission. NWCG will lead this multi-year effort and will generally start with entry level positions.

References:

NWCG Standards for M-2002 Fire Shelters, PMS 411

Date: May 15, 2023
Contact: Fire Shelter and Personal Protective Equipment Subcommittee (FSPPES)

An updated PMS 411 with a new name NWCG Standards for M-2002 Fire Shelters, is now available on the NWCG website. PMS 411 is no longer a PDF but is now an interactive web portal. The portal contains 10 sections, each explaining a different part of the fire shelter, training for its use, and the use of the fire shelter on the fireline.

References: