Reference / Glossary / Fire Service Glossary

Fire Service Glossary

A working reference of common terms used in BC wildland and structural fire service operations, incident command, and radio communications. Add JRFD-specific terms at the bottom under Local Terms.

General Fire Service

  • Apparatus — Any fire department vehicle (engine, tender, rescue, tanker, utility).
  • Backdraft — Explosive ignition of superheated gases when oxygen is suddenly introduced to an oxygen-depleted, heat-charged space.
  • BLEVE — Boiling Liquid Expanding Vapour Explosion; catastrophic failure of a pressurized vessel (e.g., propane tank) exposed to fire.
  • Defensive operations — Strategy focused on protecting exposures rather than directly attacking the main body of fire.
  • Exposure — A structure, vehicle, or area threatened by an existing fire but not yet burning.
  • Flashover — Near-simultaneous ignition of all combustible material in an enclosed area.
  • Mutual aid — Agreement between departments to assist each other across jurisdictional boundaries.
  • Offensive operations — Strategy focused on direct, interior or aggressive attack on the seat of the fire.
  • Overhaul — Searching for and extinguishing hidden or remaining fire after the main body is knocked down.
  • PPE — Personal Protective Equipment (bunker gear, helmet, gloves, boots, SCBA, etc.)
  • PPV — Positive Pressure Ventilation; using fans to pressurize and ventilate a structure.
  • RIT/RIC — Rapid Intervention Team/Crew; a standby crew dedicated to rescuing firefighters in trouble.
  • Salvage — Protecting property and contents from smoke, water, and fire damage.
  • Size-up — The ongoing process of evaluating an incident to determine strategy and resource needs.
  • Staging area — A location where resources await assignment.
  • Tender/Tanker — Apparatus whose primary function is to transport water.

Incident Command System (ICS) / BCERMS

  • AAR — After Action Review; debrief held after an incident or exercise.
  • Branch — An organizational level with responsibility for a major part of incident operations, between Division/Group and Section.
  • BCERMS — British Columbia Emergency Response Management System; BC's adaptation of ICS for all-hazard response, used by local governments, BCWS, and EMBC.
  • Chain of command — The orderly line of authority within the levels of an incident organization.
  • Command — The act of directing, ordering, and/or controlling resources by virtue of explicit legal, agency, or delegated authority.
  • Common terminology — Standardized titles, terms, and definitions used across agencies so everyone understands roles and resources the same way.
  • Demobilization (Demob) — The orderly, safe, and efficient return of resources to their original location once no longer needed.
  • Division — Organizational level responsible for operations within a defined geographic area (e.g., Division A = the north side of a structure or fire perimeter).
  • EOC — Emergency Operations Centre; off-site facility coordinating resources and support for an incident.
  • Group — Organizational level responsible for a functional assignment at an incident (e.g., Structure Protection Group, Evacuation Group), not tied to geography.
  • IAP — Incident Action Plan; the objectives and tactics for an operational period.
  • IC — Incident Commander; the individual responsible for all incident activities, including strategy and tactics, and for ordering/releasing resources.
  • ICP — Incident Command Post; the location from which the IC operates.
  • Operational period — The time scheduled for executing a given set of tactical actions, as specified in the IAP (often 12 or 24 hours).
  • PIO — Public Information Officer; manages media and public communications.
  • Span of control — The number of resources one supervisor can effectively manage, ideally 3–7, with 5 being optimal.
  • Unified command — A structure that allows agencies with different legal/jurisdictional responsibilities to work together without affecting individual agency authority.

Wildfire / BCWS Terms

  • Aerial ignition — Deliberate ignition of fuel from aircraft (e.g., for planned ignitions/burnoff operations).
  • Anchor point — An advantageous location, usually a barrier to fire spread, from which to start constructing a fireline.
  • BCWS — BC Wildfire Service.
  • Black — Area that has already burned; often used as a safety zone.
  • Candling/Torching — A single tree or small group of trees igniting fully, from bottom to top.
  • Containment — A fire is considered contained when a control line has been completed around it (and any associated spot fires) which can reasonably be expected to stop the fire's spread.
  • Control line — A comprehensive term for all constructed or natural barriers and treated fire edges used to control a fire.
  • Crown fire — Fire that advances through the tree canopy, independent of or in addition to a surface fire.
  • FBP System — Canadian Forest Fire Behaviour Prediction System; predicts rate of spread, fuel consumption, and fire intensity based on fuel type, weather, and topography.
  • Fire behaviour — The manner in which a fire reacts to fuel, weather, and topography.
  • Fireguard — A constructed barrier (often by hand tools or machinery) intended to stop or slow the spread of fire.
  • FWI System — Canadian Forest Fire Weather Index System; rates fire danger from weather observations (FFMC, DMC, DC, ISI, BUI, FWI codes).
  • Green — Unburned fuel/vegetation.
  • Head of fire — The most rapidly spreading portion of a fire's perimeter, normally with the longest flame lengths, usually downwind/upslope.
  • Hot spot — A particularly active part of a fire.
  • Mop-up — Extinguishing or removing burning material near control lines, felling snags, and trenching logs to prevent rolling material from crossing control lines.
  • Rate of spread (ROS) — Speed at which a fire moves across the landscape, usually expressed in m/min.
  • Slop-over — Fire that crosses a control line or natural barrier.
  • Spot fire — Fire ignited outside the perimeter of the main fire by a firebrand/ember.
  • Structure protection unit (SPU) — Portable sprinkler/pump kits deployed to protect structures from radiant heat and embers during a wildfire.
  • Wildland-Urban Interface (WUI) — The zone where structures and other human development meet or intermingle with wildland/vegetative fuels.

Radio / Communications

  • 10-4 — Acknowledged / message received (avoid relying on 10-codes for inter-agency traffic; plain language is preferred).
  • Air-to-ground — Radio communication between aircraft and ground crews.
  • Channel plan — The list of assigned radio frequencies/channels for an incident or department.
  • FireCom — The radio channel naming convention used regionally for fire communications (e.g., FireCom 1, FireCom 3).
  • Plain language — Clear, common terminology used instead of codes, required for all multi-agency incidents.
  • Repeater — A radio site that receives and re-transmits a signal to extend coverage.
  • Tone-out / Page-out — Dispatch alert sent to a department's pagers/radios for a call.
  • Traffic — Radio messages/communications.

Local Terms

Add Joe Rich / JRFD-specific terms, nicknames for roads or areas, and local landmark names here so new members and mutual aid partners can follow local radio traffic.

  • (add local terms here)