- NFPA 1001
- The Standard for Fire Fighter Professional Qualifications — the job performance requirements (JPRs) defining Firefighter I and II.
- IFSAC
- International Fire Service Accreditation Congress — one of two bodies that accredit fire certifications, alongside the Pro Board.
- Pro Board
- National Board on Fire Service Professional Qualifications — accredits fire certifications and issues nationally recognized certificates.
- Job performance requirement (JPR)
- A statement in NFPA 1001 of a task a firefighter must perform, the tools used, and the expected outcome.
- Incident Command System (ICS)
- A standardized, modular management structure for organizing personnel, equipment, and communications at an incident.
- Unity of command
- The principle that each member reports to and takes orders from only one supervisor.
- Span of control
- The number of subordinates one supervisor can effectively manage — about 3 to 7, with 5 ideal.
- Incident commander (IC)
- The person with overall responsibility for managing an incident until command is transferred or terminated.
- Division (ICS)
- A geographic assignment supervising all work in a defined area, such as a floor or the rear of a building.
- Group (ICS)
- A functional assignment supervising a specific task wherever it occurs — ventilation, search, or salvage.
- Unified command
- An ICS structure letting multiple agencies share management of a single incident under common objectives.
- Mutual aid
- A pre-arranged agreement under which neighboring departments assist one another with personnel and equipment.
- Personnel accountability system
- A system (tags or PAR checks) that lets command always know who is operating where on the fireground.
- Standard operating procedure (SOP/SOG)
- A written department guideline describing how a routine task or operation is performed, reducing injuries.
- Two-in/two-out rule
- OSHA rule: at least two firefighters work together inside an IDLH atmosphere while at least two stand ready outside to rescue them.
- IDLH atmosphere
- Immediately Dangerous to Life and Health — poses an immediate threat of death or injury; a structure-fire interior is always IDLH.
- Type I construction
- Fire-resistive — protected noncombustible materials designed to resist fire for a rated period.
- Type II construction
- Noncombustible — unprotected steel and masonry; the steel can fail and elongate under heat.
- Type III construction
- Ordinary — masonry exterior walls with a combustible interior; concealed spaces let fire spread.
- Type IV construction
- Heavy timber / mass timber — large-dimension wood members that char slowly and resist early collapse.
- Type V construction
- Wood-frame — combustible throughout; spreads fire fast and, with lightweight trusses, can collapse early.
- Lightweight truss
- Engineered floor/roof assembly that loses strength fast under fire and can fail and collapse early with little warning.
- Chain of command
- The paramilitary ranking through which orders and accountability flow in a fire department.
- NIMS
- National Incident Management System — the framework, including ICS, that lets agencies work together at incidents.
- Establishing command
- The first-arriving officer's standardized action of assuming and announcing incident command.
- Plain language (radio)
- Using clear everyday words instead of agency-specific ten-codes so all units, including mutual aid, understand alike.
- Initial radio report
- The first-arriving officer's brief on-scene size-up of what they have at the incident.
- Progress report
- An update to command on the status of operations, using standard benchmarks like 'water on the fire.'
- Mayday
- The radio signal a firefighter transmits when trapped, lost, disoriented, out of air, or injured — the top priority.
- LUNAR / LIP report
- The Mayday format: Location, Unit, Name, Assignment, Resources needed (a LIP variant: Location, Identity, Problem).
- Urgent message
- A radio transmission reporting a serious change in conditions — not a firefighter in distress (that is a Mayday).
- Radio silence
- An order, often after a Mayday, that all units cease non-essential transmissions to keep the channel clear.
- Telecommunicator (dispatcher)
- The communications-center member who answers calls, gathers location first, alerts units, and time-stamps the incident.
- Size-up
- The ongoing mental evaluation of an incident's conditions, hazards, and resource needs that drives strategy.
- Benchmark (fireground)
- A standard reported milestone — 'water on the fire,' 'primary search complete,' 'fire under control.'
- PAR (personnel accountability report)
- A roll-call check of crews to confirm everyone is accounted for at a set interval or after an event.
- Rapid intervention crew (RIC)
- A standby team dedicated to rescuing downed or trapped firefighters; activated on a Mayday.
- Fire tetrahedron
- The four elements of combustion: fuel, oxygen, heat, and a self-sustained chemical chain reaction; remove any one to extinguish.
- Fire triangle
- The older three-element model — fuel, oxygen, heat — that the tetrahedron expands by adding the chemical chain reaction.
- Self-sustained chemical chain reaction
- The ongoing reaction keeping a flame going — the tetrahedron's fourth side, interrupted by dry-chemical agents.
- Ignition
- The stage when fuel, heat, and oxygen combine and combustion begins; the fire is small and localized.
- Growth stage
- The fire spreads and the compartment heats, with hot gases banking down — conditions move toward flashover.
- Fully developed stage
- All available fuel is burning and heat release peaks; the fire is ventilation- or fuel-limited.
- Decay stage
- Fuel or oxygen is consumed and heat release falls; an oxygen-starved, heat-charged decay fire enables backdraft.
- Flashover
- Near-simultaneous ignition of all compartment contents from intense radiant heat — the deadly transition during growth.
- Backdraft
- A smoke (gas) explosion when oxygen is suddenly introduced to a confined, oxygen-starved, heat-charged space.
- Rollover (flameover)
- Flames rolling across the unburned gases banked at the ceiling, ahead of the main fire — a warning of flashover.
- Thermal layering
- The tendency of hot smoke and gases to rise and stratify above cooler air; firefighters stay low and avoid disrupting it.
- Conduction
- Heat transfer directly through a solid object, such as along a metal beam to an adjoining space.
- Convection
- Heat transfer by movement of hot smoke and gases — the main way fire spreads vertically in a building.
- Radiation
- Heat transfer by electromagnetic waves through space; the primary cause of flashover and of exposure fires across a gap.
- Class A fire
- Ordinary combustibles — wood, paper, cloth, plastics; extinguished by cooling with water.
- Class B fire
- Flammable and combustible liquids and gases; extinguished by smothering with foam, CO₂, or dry chemical.
- Class C fire
- Energized electrical equipment; use a non-conductive agent — it becomes Class A once de-energized.
- Class D fire
- Combustible metals such as magnesium, titanium, or sodium; use a special dry-powder agent — never water.
- Class K fire
- Cooking oils and fats in commercial kitchens; extinguished with a wet-chemical agent that saponifies the oil.
- PASS (extinguisher method)
- Pull the pin, Aim at the base of the fire, Squeeze the handle, Sweep side to side.
- PASS device
- Personal Alert Safety System — a motion-sensing alarm that sounds when a firefighter is motionless, to locate a downed firefighter.
- Bunker (turnout) gear
- Structural PPE built in layers — outer shell, moisture barrier, thermal liner — for thermal and abrasion protection.
- Moisture barrier
- The turnout-gear layer that keeps water and other liquids out while allowing some vapor transmission.
- SCBA
- Self-contained breathing apparatus — an open-circuit, positive-pressure unit supplying clean air for interior firefighting.
- Positive pressure (SCBA)
- Higher-than-atmospheric pressure in the facepiece so contaminated air cannot leak in past the seal.
- Low-air alarm
- The SCBA warning to begin exiting toward a safe area — it signals 'leave now,' not 'air is gone.'
- RIC/UAC
- Rapid intervention crew universal air connection — lets a downed firefighter receive emergency air from a rescuer.
- Controlled (skip) breathing
- An SCBA emergency technique of slow, deliberate breaths to extend the remaining air supply.
- Solid (straight) stream
- A compact water column giving maximum reach and penetration with minimal disruption of thermal layering.
- Fog stream
- Water broken into fine droplets to increase surface area for heat absorption; adjustable from a combination nozzle.
- Smooth-bore nozzle
- A nozzle producing a solid stream, valued for reach, penetration, and lower nozzle reaction.
- Combination nozzle
- A nozzle adjustable between a straight stream and a fog pattern.
- Friction loss
- The pressure lost as water moves through hose and fittings; rises with flow and length, falls with larger diameter.
- Water hammer
- A damaging pressure surge from stopping or changing water flow too quickly; prevented by operating valves slowly.
- Forward lay
- A hose lay dropping a supply line at the water source, then driving to the fire.
- Reverse lay
- A hose lay running a supply line from the fire back to the water source.
- Preconnected attack line
- Hose loaded and connected so it can be quickly pulled and advanced to a fire.
- Set of irons
- A flat-head axe and a Halligan bar carried together — the core forcible-entry combination.
- Halligan bar
- A multipurpose forcible-entry prying tool with an adze, a pick, and a fork end.
- Through-the-lock entry
- A forcible-entry method that removes or manipulates the lock cylinder, preserving the door and lock.
- Vertical ventilation
- Making a roof opening so heat and smoke rise straight up and out, away from interior crews.
- Horizontal ventilation
- Releasing heat and smoke through windows, doors, or wall openings at the same level as the fire.
- Positive-pressure ventilation (PPV)
- Using a blower to pressurize a structure and push smoke out through an established exhaust opening.
- Coordinated ventilation
- Timing venting with a charged attack line so the added oxygen does not cause flashover or backdraft.
- Offensive attack
- An interior attack advancing hoselines to the seat of the fire when the structure is tenable and savable.
- Defensive attack
- An exterior attack protecting exposures with master streams when a building is too involved or unstable to enter.
- Direct attack
- Applying water directly onto the burning fuel.
- Indirect attack
- Applying water onto hot surfaces of an unoccupied space to generate steam that smothers the fire.
- Transitional attack
- A quick exterior knockdown of the fire before transitioning to an interior attack.
- Class B foam
- Foam designed for flammable/combustible liquids; forms a blanket separating fuel from air and suppressing vapor.
- Class A foam
- Foam that improves water's penetration and effectiveness on ordinary combustibles like wood and paper.
- Overhaul
- Finding and extinguishing hidden or smoldering fire after the main fire is out — full PPE and SCBA stay on.
- Salvage
- Operations protecting property and belongings from fire, smoke, and water damage during and after suppression.
- Thermal imaging camera (TIC)
- A device that detects heat to locate victims, fire spread, and hidden smoldering fire during search and overhaul.
- Exposure
- A nearby structure or object threatened by radiant heat from a fire that must be protected.
- 75-degree climbing angle
- The proper angle for placing a ground ladder against a building for safe climbing.
- Roof ladder
- A ground ladder with folding hooks at the top to secure it over a roof ridge or peak.
- Pump discharge pressure
- The pressure the pump must produce to overcome friction loss and elevation and deliver an effective nozzle pressure.
- Primary search
- A rapid initial search for victims while fire conditions are active, to find anyone in immediate danger.
- Secondary search
- A slower, thorough search of the whole structure after the fire is controlled, ideally by a fresh crew.
- VEIS
- Vent, Enter, Isolate, Search — a tactic to search an isolated room, isolating it (closing the door) before searching.
- Wall-following (search)
- Keeping one hand in contact with a wall to maintain orientation while searching in heavy smoke.
- Search rope (tag line)
- A guideline used during searches of large or complex areas so a crew can find its way back out.
- Clothing drag
- A victim-removal technique pulling the victim by the clothing while the rescuer stays low.
- Blanket drag
- A removal technique using a blanket to slide a victim along the floor, distributing support.
- Webbing drag
- Using a loop of webbing around a victim to assist in dragging them to safety.
- Vehicle extrication
- The process of freeing trapped patients from a wrecked vehicle.
- Vehicle stabilization
- Securing a vehicle with cribbing or step chocks so it cannot move before crews work near or in it.
- Cribbing
- Wood or composite blocks stacked (e.g., a box crib) to stabilize a vehicle or load before extrication.
- Box crib
- Blocks arranged in an interlocking, alternating square pattern to build a stable support under a load.
- Step chocks
- Stepped cribbing placed under the rocker panels to stabilize an upright wrecked vehicle.
- Hydraulic spreaders
- Rescue tool that pushes apart or pulls vehicle components — part of the 'jaws of life.'
- Hydraulic cutters
- Rescue tool that shears through metal posts, door hinges, and pillars during disentanglement.
- Hydraulic ram
- A rescue tool that pushes the dashboard or a component to free a trapped patient.
- Disentanglement
- The extrication phase of creating space and pathways — often removing a door or the roof — to free the patient.
- Blocking (apparatus)
- Positioning apparatus to create a protected work area shielding crews from traffic at a roadway incident.
- Undeployed airbag hazard
- An airbag that has not gone off and could deploy during extrication — crews avoid its path and inflators.
- Life-safety rope
- Rope used to support firefighters or victims; removed from life-safety service if shock-loaded or damaged.
- Utility rope
- Rope for non-life-bearing tasks such as hoisting tools; never used to bear a person's weight.
- Figure-eight knot
- A strong, easily inspected stopper or loop knot favored for life safety and relatively easy to untie after loading.
- Figure-eight follow-through
- A figure-eight tied around an anchor and traced back through, forming a secure fixed loop.
- Clove hitch
- A knot used to secure a rope to an object such as a tool or post for hoisting.
- Bowline
- A knot forming a fixed loop that will not slip under load.
- Dressing a knot
- Removing twists and aligning a knot's parts so it holds properly and can be inspected.
- Hose service test
- Charging hose to a designated test pressure for a set time to confirm it is safe for service; failed sections are removed.
- Drying hose
- Thoroughly drying fire hose before storage to prevent mildew and rot that weaken the jacket and lining.
- Hydrostatic test (cylinder)
- A pressure test confirming an SCBA cylinder holds its rated pressure — every 5 years (steel/aluminum) or 3 years (composite).
- Composite SCBA cylinder
- A fiberglass or carbon-fiber wrapped cylinder hydrostatically tested every 3 years with a limited service life.
- SCBA inspection
- A before-shift check of the facepiece, head straps, regulator, air gauge, and air level before placing it in service.
- Preventive maintenance
- Scheduled inspection and service to catch a failing tool, ladder, or pump before it fails on the fireground.
- Maintenance records
- Accurate logs proving equipment is ready and tracking when service or testing is due.
- Ground ladder inspection
- Checking ladders after each use and on schedule for cracks, heat damage, and worn parts — heat can weaken them invisibly.
- Tool maintenance
- Keeping hand and forcible-entry tools clean and sharp and replacing cracked or loose handles before use.
- Pump test
- Periodically operating and testing a fire pump, even between calls, and keeping intakes and strainers clear.
- Fire cause determination (FFII)
- The Firefighter II duty that begins at locating the area of origin and recognizing the cause may be suspicious.
- Evidence preservation
- Avoiding moving or discarding burned materials and limiting access so investigators can determine cause and origin.
- Area of origin
- The location where a fire began — the Firefighter II locates and documents it and watches for suspicious indicators.
- Pre-incident survey
- A walkthrough gathering building information (layout, hazards, water supply, systems) to plan a future response.
- Standpipe system
- Piping and outlets letting firefighters connect hoselines for water on upper floors, vital in high-rises.
- Class I standpipe
- A standpipe with 2½-inch outlets for fire department hose connections.
- Fire department connection (FDC)
- An exterior inlet through which the fire department pumps extra water into a sprinkler or standpipe system.
- Automatic sprinkler system
- A built-in system in which only heads exposed to enough heat activate, applying water directly over the fire.
- Wet-pipe sprinkler system
- The common system holding water in the pipes at all times so a single activated head flows immediately.
- Smoke alarm placement
- Inside each bedroom, outside each sleeping area, and on every level; interconnected and replaced about every 10 years.
- Nuisance alarm
- A false smoke-alarm activation (often from cooking or steam) — keep alarms away from kitchens and bathrooms.
- Public fire safety education
- A Firefighter II task teaching residents prevention, smoke alarms, and escape planning to reduce fire deaths.
- Stop, drop, and roll
- The action-based lesson taught to smother flames on a person's clothing, especially for children.
- NFPA 704 diamond
- Hazard placard: blue health, red flammability, yellow instability/reactivity (each 0–4), white special hazards.
- NFPA 704 health (blue)
- The left, blue quadrant rating how harmful a material is to the body, from 0 (none) to 4 (deadly).
- NFPA 704 flammability (red)
- The top, red quadrant rating how easily a material ignites, from 0 (won't burn) to 4 (extremely flammable).
- NFPA 704 reactivity (yellow)
- The right, yellow quadrant rating instability/reactivity, from 0 (stable) to 4 (may detonate).
- Emergency Response Guidebook (ERG)
- A DOT first-response guide for identifying hazards and initial protective actions at a transportation hazmat incident.
- UN/NA identification number
- The four-digit number used to look up a hazardous material's guide page and protective distances in the ERG.
- DOT placard
- A diamond label on transport vehicles/containers indicating the hazard class of the material being carried.