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PMS 205

NWCG Glossary of Wildland Fire

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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.  

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Term Steward Status Definition
abandoned/unattended CEPC Communication, Education, and Prevention Committee In Development
ABCD Miscellaneous DMC Data Management Committee, IBC Incident Business Committee Approved A FireCode used by the USDA Forest Service to track and compile cost information for emergency initial attack fire suppression expenditures for A, B, C, & D size class fires on Forest Service lands.
abort NIAC National Interagency Aviation Committee Approved To jettison a load of water or retardant from an aircraft, or terminate a preplanned aircraft maneuver.
abort area NIAC National Interagency Aviation Committee Approved A designated area where unused quantities of water or fire retardant may be jettisoned, usually to permit an airtanker to land with less than a full load.
Above Ground Level NIAC National Interagency Aviation Committee Approved Term frequently used in aviation operations, usually in connection with a stated altitude.
abrasion MFES Mobile Fire Equipment Subcommittee Approved Grinding or wearing away of a surface by rough materials.
abscess EMC Emergency Medical Committee Approved A localized collection of pus surrounded by inflamed tissue.
absolute humidity FWS Fire Weather Subcommittee Approved According to the American Meteorological Society, (also called vapor density). In a system of moist air, the ratio of the mass of water vapor present to the volume occupied by the mixture; that is, the density of the water vapor component.
absorption CEPC Communication, Education, and Prevention Committee Approved Act of soaking up and retaining a gas in liquid or in a solid; also retention of radiant energy.
accelerant CEPC Communication, Education, and Prevention Committee Approved Material (usually a flammable liquid) used to initiate or increase the spread of a fire.
accelerant misuse CEPC Communication, Education, and Prevention Committee In Development
acceptable fire risk FUSC Fire Use Subcommittee Approved The potential fire loss a community is willing to accept rather than provide resources to reduce such losses.
accessibility burn FUSC Fire Use Subcommittee Approved The burning of understory prior to the sale of forest products to improve the efficiency of timber marking and harvesting.
accident (event) NCSC National Coordination System Committee Approved An event, usually managed by organizations external to the fire community, for which the primary focus is for dealing with an accident and assistance to potential victims. This category includes accidents such as: automobile, aircraft, train, watercraft, and industrial.
accounting code IBC Incident Business Committee Approved Agency-specific accounting data. Each agency assigns a specific accounting code to an incident.
accrual reports IBC Incident Business Committee Approved Cost reports utilized for financial obligation purposes.
accumulated debris CEPC Communication, Education, and Prevention Committee In Development
accuracy descriptor (Point of Origin) (POO) FRSC Fire Reporting Subcommittee Approved Description of the methods used to determine the certainty and precision of the fire location at the point of origin.
action plan NIMSIC National Incident Management System Integration Committee Archived Any tactical plan developed by any element of ICS in support of the incident action plan.
active crown fire IOSC Incident Operations Subcommittee, FBSC Fire Behavior Subcommittee Approved A fire in which a solid flame develops in the crowns of trees, but the surface and crown phases advance as a linked unit dependent on each other.
active fire IOSC Incident Operations Subcommittee Approved Any fire that has not been called "out".
active resources IBC Incident Business Committee Archived Resources checked in and assigned work tasks on an incident.
activity (fire cause) CEPC Communication, Education, and Prevention Committee Approved The thing that a person is doing when a wildland fire ignition occurs.
activity fuels FUSC Fire Use Subcommittee Approved Fuels resulting from, or altered by, forestry practices such as timber harvest or thinning, as opposed to naturally created fuels.
activity group CEPC Communication, Education, and Prevention Committee Approved Further refines wildfire cause supporting data, providing information for prevention programs for targeted messaging.
activity name CEPC Communication, Education, and Prevention Committee Approved Common name of activity
activity name (aviation) GSC Geospatial Subcommittee Approved Common name of the aviation activity.
activity type FRSC Fire Reporting Subcommittee Approved Type of activity or event
activity type (aviation) NIAC National Interagency Aviation Committee, GSC Geospatial Subcommittee Approved Type of aviation activity or event
actual completion date FMC Fuels Management Committee Approved Date when treatment was physically completed
Actual Time En Route (ATE) NIAC National Interagency Aviation Committee Approved Term used in flight planning/following to document actual time spent flying between points.
Actual Time of Arrival (ATA) NIAC National Interagency Aviation Committee Approved Term used in flight planning/following to document time of arrival at a point.
Actual Time of Departure (ATD) NIAC National Interagency Aviation Committee Approved Term used in flight planning/following to document time of departure from a point.
adapter ETC Equipment Technology Committee Approved A device for connecting hoses of the same size with non-matching hose threads, or connecting a threaded coupling to a quick-connect coupling.
additional fuel model FDSC Fire Danger Subcommittee Approved The fuel model which best represents an additional carrier of a fire.
adhesion MFES Mobile Fire Equipment Subcommittee Approved Bonding or adherence between rubber lining and the jacket.
adiabatic process FWS Fire Weather Subcommittee Approved According to the American Meteorological Society, a process in which a system does not interact with its surroundings by virtue of a temperature difference between them. In an adiabatic process any change in internal energy (for a system of fixed mass) is solely a consequence of working. For an ideal gas and for most atmospheric systems, compression results in warming, expansion results in cooling.
adjective rating FWS Fire Weather Subcommittee Approved A public information description of the relative severity of the current fire danger situation.
Administrative Payment Team (APT) IBC Incident Business Committee Approved A team that supports incident agencies by processing payments for resources. Resources may include emergency equipment, casuals, local vendors for supplies, etc.
Administrative Representative (AR) IBC Incident Business Committee Approved Individual responsible for incident agency business management functions, such as personnel, procurement, fiscal, etc.
administrative workweek IBC Incident Business Committee Approved Period of seven consecutive calendar days designated in advance by the head of a department (5 U.S.C. 6101(a)).
Administratively Determined (AD) IBC Incident Business Committee Approved A person hired and compensated under the Pay Plan for Emergency Workers.
admission CEPC Communication, Education, and Prevention Committee Approved Oral or written statement tending to link its maker to involvement in a particular crime.
adolescent (13-17) CEPC Communication, Education, and Prevention Committee In Development
adult (18+) CEPC Communication, Education, and Prevention Committee In Development
Advanced EMT (AEMT) EMC Emergency Medical Committee Approved An EMS professional who provides basic and limited advanced life support skills and interventions for patients within the EMS system.
Advanced Life Support (ALS) RMC Risk Management Committee Approved Advanced life support skills performed by an EMS practitioner or service, e.g. intravenous fluids and drug administration.
Advanced Life Support (ALS) EMC Emergency Medical Committee Approved Emergency medical care and interventions performed by an Advanced EMT or Paramedic with limited supervision, using critical thinking and autonomous decision making skills which includes invasive procedures and medication administration.
advancing a line IOSC Incident Operations Subcommittee Approved Moving a hose lay toward a specified area from the point where the hose-carrying apparatus has stopped.
advancing fire WFISC Wildland Fire Investigation Subcommittee Approved That portion of the fire with rapid fire spread with higher intensity which is normally burning with the wind and/or up slope.
advancing front combustion stage FBSC Fire Behavior Subcommittee Approved The period of combustion when a fire is spreading, usually accompanied by flaming combustion that releases heat to sustain the convection column.
advection FWS Fire Weather Subcommittee Approved According to the American Meteorological Society, the process of transport of an atmospheric property solely by the mass motion of the atmosphere; also the rate of change of the value of the advected property at a given point.
Advisory RMC Risk Management Committee Approved A time-sensitive alert from an NWCG Committee to the wildland fire community regarding procedural changes, equipment information and/or use updates, potential safety hazards, etc. Yellow hash-marked bordered stationary will be associated with this type of alert.
Adze Hoe ETC Equipment Technology Committee Approved A fire-trenching or digging tool having a sharp, tempered blade, which is useful for heavy grubbing, trenching, and light cutting.
aerial detection IASS Interagency Aerial Supervision Subcommittee Approved A system for, or the act of discovering, locating, and reporting fires from aircraft.
aerial fireworks CEPC Communication, Education, and Prevention Committee In Development Explode or create an aerial flash. The hot remains of an aerial firework may land in flammable vegetation and ignite a fire.    
aerial fuels FUSC Fire Use Subcommittee Approved Standing and supported live and dead combustibles not in direct contact with the ground and consisting mainly of foliage, twigs, branches, stems, cones, bark, and vines.
aerial ignition IOSC Incident Operations Subcommittee, NIAC National Interagency Aviation Committee Approved Ignition of fuels by dropping incendiary devices or materials from aircraft.
Aerial Ignition Device (AID) NIAC National Interagency Aviation Committee, ETC Equipment Technology Committee Approved Inclusive term applied to equipment designed to ignite wildland fuels from an aircraft.
aerial reconnaissance IASS Interagency Aerial Supervision Subcommittee Approved Use of aircraft for detecting and observing fire behavior, values-at-risk, suppression activity, and other critical factors to facilitate command decisions on strategy and tactics needed for fire suppression.
aerial torch IHOPS Interagency Helicopter Operations Subcommittee Approved An ignition device suspended under a helicopter, capable of dispensing ignited fuel to the ground for assistance in burning out or backfiring.
affidavit CEPC Communication, Education, and Prevention Committee Approved A statement of declaration in writing and affirmed before an official with authority to administer an oath; a statement of declaration alleging fact to support the issuance of a search or arrest warrant.
After Action Review (AAR) RMC Risk Management Committee Approved A structured review or de-brief process of an event, focused on performance standards, that enables participants to discover for themselves what happened, why it happened, and how to sustain strengths and improve on weaknesses. After action reviews, informal or formal, follow the same general format, involve the exchange of ideas and observations, and focus on improving performance.
age category CEPC Communication, Education, and Prevention Committee In Development Categories for individuals based on their age group to tailor fire safety messages, eduction and prevention efforts effectively. The aim is to identify how different age groups may be involved in wildfire ignition activities, either directly or indirectly, and to address their specific needs or behaviors.   A way to group people based on their chronological age and their position in the life cycle as it relates to the age demographic. This information provides valuable insight to Communication, Education, and Prevention personnel in developing products to reach and educate on wildland fire prevention.
agency NIMSIC National Incident Management System Integration Committee Archived An administrative division of a government with a specific function, or a non-governmental organization (e.g., private contractor, business, etc.) that offers a particular kind of assistance. A federal, Tribal, state or local agency that has direct fire management or land management responsibilities or that has programs and activities that support fire management activities.
agency administrator NIMSIC National Incident Management System Integration Committee Approved The official position responsible for the management of a geographic unit or functional area. The managing officer of an agency, division thereof, or jurisdiction having statutory responsibility for incident mitigation and management. Examples: Federal Line Officer, State Forest Officer/Delegate or Fire Manager, Tribal Chairperson, Fire Chief, Police Chief, Sheriff, Mayor or County Representative.
agency certification IPSC Incident and Position Standards Committee Approved The process whereby the employing agency or contractor documents that the individual is fully qualified to perform duties and responsibilities for a specified position.
agency dispatch IBC Incident Business Committee, NCSC National Coordination System Committee Approved The agency or jurisdictional facility from which resources are allocated to incidents.
agency dispatcher IBC Incident Business Committee, NCSC National Coordination System Committee Approved A person working within an agency organization who processes resources to and from incidents.
agency pilot NIAC National Interagency Aviation Committee Approved A federal employee pilot or pilot contracted by a federal agency to fly agency, contracted or leased aircraft. This does not include pilots employed by an aircraft vendor as part of an aircraft services contract, such as airtanker contracts, helicopter contracts or other aircraft contracts.
agency program support (event) NCSC National Coordination System Committee Approved An event, managed by one of the fire agency's other (non-fire) program areas, for accomplishing activities deemed necessary by agency management. 
agency specific costs IBC Incident Business Committee Approved Costs incurred by an agency that address the sole concern of only the agency or are not incurred with mutual benefit. Agency specific costs are not shared.
air accident (event) Approved An event dealing with an accident or mishap involving aircraft.
air ambulance RMC Risk Management Committee Approved A rotary wing aircraft configured, staffed and equipped to respond, care for and transport a patient(s) and approved/licensed by a state to do so. An air ambulance is sometimes referred to as a medevac.
air attack NIAC National Interagency Aviation Committee Approved The deployment of fixed-wing or rotary aircraft on a wildland fire, to drop retardant or extinguishing agents, shuttle and deploy crews and supplies, or perform aerial reconnaissance of the overall fire situation.
air attack base NIAC National Interagency Aviation Committee Approved Permanent facility at which aircraft are stationed for use in air attack operations.
air cargo NIAC National Interagency Aviation Committee Approved All items for transport and delivery by aircraft.
air contaminant FUSC Fire Use Subcommittee Approved An airborne dust, fume, gas, mist, odor, smoke, vapor, soot, pollen, carbon, acid or particulate matter or any combination thereof.
air crew member NIAC National Interagency Aviation Committee In Development Additional crew member required for accomplishment of the mission such as flight attendant, smokejumper/rappel spotter, cargo loadmaster, helicopter manager, etc. These positions usually do not require any Airman Certificate(s) or a flight physical. Referred to as a Qualified Non-Crew Member in the CFR.
air guard NCSC National Coordination System Committee Approved A common VHF-FM frequency used by natural resource agency aircraft for emergency radio transmissions.
air mass FWS Fire Weather Subcommittee Approved According to the American Meteorological Society, a widespread body of air that is approximately homogeneous in its horizontal extent, particularly with reference to temperature and moisture distribution; in addition, the vertical temperature and moisture variations are approximately the same over its horizontal extent.  The properties of the air mass are established while that air was situated over a particular region of the earth's surface.
air pack RMC Risk Management Committee Approved Portable air (not oxygen) tanks with regulators which allow firefighters to breathe while in toxic smoke conditions. Usually rated for 30 minutes of service. Used primarily on fires involving structures or hazardous materials.
air pollution FUSC Fire Use Subcommittee Approved The general term referring to the undesirable addition of substances (gases, liquids, or solid particles) to the atmosphere that are foreign to the natural atmosphere or are present in quantities exceeding natural concentrations.
air pollution alert FUSC Fire Use Subcommittee Approved A statement issued by an Air Quality Regulatory Agency due to high measured concentrations of pollutants. The alert remains in effect until monitoring shows a decrease in pollutant levels. Should conditions worsen, air pollution warnings and emergencies may be issued. At each stage (alert, warning and emergency) additional emission restrictions are put into effect so as to not intensify the situation. Essentially, at the emergency level all industrial activities and auto usage stop. 
air quality FUSC Fire Use Subcommittee Approved The composition of air with respect to quantities of pollution therein; used most frequently in connection with "standards" of maximum acceptable pollutant concentrations. Used instead of "air pollution" when referring to programs.
air quality model FUSC Fire Use Subcommittee Approved Mathematical or quantitative representation or simulation of air quality processes; e.g., emission models, receptor models, or air quality dispersion models.
Air Stagnation Advisory (ASA) FWS Fire Weather Subcommittee Approved A statement issued by a National Weather Service forecast office when atmospheric conditions are stable enough such that the potential exists for air pollutants to accumulate in a given area. The statement is initially issued when conditions are expected to last for at least 36 hours. 
aircraft (specific cause) CEPC Communication, Education, and Prevention Committee In Development An airplane, helicopter, or other machine capable of flight.
aircraft accident NIAC National Interagency Aviation Committee Approved An unplanned event that does substantial damage or causes serious injuries when associated with the operation of applicable aircraft. Event occurs between the time engine(s) is (are) started or rotors turning for the purpose of commencing flight, until the aircraft comes to rest with engines and propellers or rotors stopped, the brakes set or wheel chocks in place, and all persons have disembarked. 
aircraft data card NIAC National Interagency Aviation Committee Approved Card or documentation required to be on board the aircraft which approves use and indicates specific types of use.
aircraft footprint NIAC National Interagency Aviation Committee Approved That area on the surface of the earth, runway, or ramp that is covered by the tread of the aircraft tire while the aircraft is motionless.
aircraft ground mishap NIAC National Interagency Aviation Committee Approved An aircraft mishap in which there is no intent to fly. However, the power plants and/or rotors are in operation and damage is incurred requiring replacement or repair of rotors, propellers, wheels, tires, wing tips, flaps, etc., or injury is incurred requiring first-aid or medical attention.
aircraft incident NIAC National Interagency Aviation Committee Approved An unplanned event that results in damage which is less than serious aircraft incident criteria, or injuries not requiring medical attention.
Aircraft Network (AirNet) NCSC National Coordination System Committee Approved Applies to radio frequencies primarily used for air operations.
airtanker NIAC National Interagency Aviation Committee Approved Fixed-wing aircraft certified by FAA as being capable of transport and delivery of fire retardant solutions.
Alert System RMC Risk Management Committee Approved A method used to distribute various types of general or time-sensitive information from an NWCG committee to the wildland fire community. Information may include bulletins, advisories, or safety warnings, each with an associated color hash-marked bordered stationary.
alidade ETC Equipment Technology Committee Approved A sighting device used by lookouts to determine the horizontal bearing and sometimes the vertical angle of a fire from a lookout.
all hazard incident NIMSIC National Incident Management System Integration Committee Approved A threat or an incident, natural or manmade, that warrants action to protect life, property, the environment, and public health or safety, and to minimize disruptions of government, social, or economic activities. It includes natural disasters, cyber incidents, industrial accidents, pandemics, acts of terrorism, sabotage, and destructive criminal activity targeting critical infrastructure. This also includes the effects climate change has on the threats and hazards.
All Hazards Meteorological Response System (AMRS) FWS Fire Weather Subcommittee Approved A mobile weather data collection and forecasting system consisting of a communications module, weather observing module, and data interigation module. Used by incident meteorologists on an incident.
All Terrain Vehicle (ATV) ETC Equipment Technology Committee Approved Any motorized vehicle designed for or capable of cross-country travel on or immediately over land, water, sand, snow, ice, marsh, swampland, or other terrain.
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NWCG Latest Announcements

NEW! Incident Performance and Training Modernization Story Map Now Available

Date: Aug 26, 2025
Questions? Please contact:
National Wildfire Coordinating Group

NWCG is excited to announce the launch of the Incident Performance and Training Modernization (IPTM) Story Map, a new interactive resource that showcases how NWCG is transforming wildland fire training and qualifications through a performance-based system.

Since its launch in 2023, IPTM has made major strides in updating how we manage incident positions:

  • 36 incident positions now have new Incident Position Standards and Next Generation Position Task Books available for field use
  • 6 more incident positions are nearing completion
  • 111 total incident positions are being analyzed through the IPTM initiative

The Story Map guides you through the IPTM process, highlights key accomplishments, and outlines what’s ahead. Whether you are a trainer or a trainee, this tool offers valuable insight into the modernization effort shaping the future of wildland fire training and qualifications.

This effort would not be possible without the contributions of NWCG staff, NWCG committees, and hundreds of subject matter experts across the wildland fire community.

References:

IPTM Story Map

Incident Performance and Training Modernization Webpage

NEW! S-290, Intermediate Wildland Fire Behavior (Blended) Available Now

Date: Aug 15, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that the S-290, Intermediate Wildland Fire Behavior (Blended) training is now available on the Wildland Fire Learning Portal. S-290 (Blended) training combines online training and instructor-led training components that support individuals working towards any Single Resource Boss or Fire Effects Monitor incident qualifications.

This second course in the series collectively serves to develop fire behavior prediction knowledge and skills, and provides more detailed information on fuels, weather, and topography that affect wildland fire behavior for safety purposes.

Students are required to finish the prerequisite S-190, Introduction to Wildland Fire Behavior, before enrolling in S-290, Intermediate Wildland Fire Behavior (Blended).

References:

S-290, Intermediate Wildland Fire Behavior (Blended)

S-190, Introduction to Wildland Fire Behavior

Wildland Fire Learning Portal

NEW! S-271, Helicopter Crewmember (Blended) Now Available

Date: Aug 14, 2025
Questions? Please contact:
Interagency Helicopter Operations Subcommittee

The S-271, Helicopter Crewmember (Blended) is now available. Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Helicopter Crewmember (HECM) incident qualifications. 

S-271, Helicopter Crewmember (Blended) training combines online training and instructor-led training components. This course is designed to provide students with the knowledge and skills necessary to perform the duties of the HECM position, as described in the NWCG Incident Position Standards for Helicopter Crewmember, PMS 350-22.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

S-271, Helicopter Crewmember (Blended)

NWCG Helicopter Crewmember (HECM) Position Page

Wildland Fire Learning Portal

Incident Position Standards and Next Generation Position Task Books Now Available for FBAN and LTAN

Date: Aug 13, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that Incident Position Standards and Next Generation Position Task Books are now available for Fire Behavior Analyst (FBAN) and Long Term Fire Analyst (LTAN).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization (IPTM) effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

NWCG Fire Behavior Analyst Position Page

NWCG Long Term Fire Analyst Page