Fire Service Dictionary
Accelerant
Flammable fuel (often liquid) used by some arsonists to increase size or intensity of fire. May also be accidentally introduced when HAZMAT becomes involved in fire.
Accountability
The process of emergency responders (fire, police, SAR, emergency medical, etc...) checking into and making themselves announced as being on-scene during an incident to an incident commander or accountability officer. Through the accountability system, each person is tracked throughout the incident until released from the scene by the incident commander or accountability officer. This is becoming a standard in the emergency services arena primarily for the safety of emergency personnel. This system may implement a name tag system or personal locator device (tracking device used by each individual that is linked to a computer).Willoughbyccfd5 23:52, 3 December 2006 (UTC)
Adapter
plumbing accessories for connecting hoses and pipes of incompatible diameter, thread, or gender. See also reducer, increaser, double male, double female, water thief. May contain combinations, such as a double-female reducer. Adapters between multiple hoses are called wye, Siamese, or distributor, which see below.
Aerial Apparatus
Fire truck having an attached extension ladder, nozzle, man-lift-bucket, or similar device raised using power from the truck. May also carry other portable ladders and tools.
Air monitoring Meter
Electronic device for measuring the presence of one or more chemicals in air, such as oxygen, carbon monoxide, hydrogen sulfide or volatile organic compounds; may have preset danger threshold alarms.
Airbags
(1) inflatable device used for lifting or spreading; (2) vehicle safety device with potential explosion hazard during vehicle extrication if not already blown.
Air-pack
Jargon for self-contained breathing apparatus (SCBA).
Alarm (Automatic Fire Alarm AFA)
(1) system for detecting and reporting unusual conditions, such as smoke, fire, flood, loss of air, HAZMAT release, etc; (2) a specific assignment of multiple fire companies and/or units to a particular incident, usually of fire in nature; (3) centralized dispatch center for interpreting alarms and dispatching resources. See fire alarm control panel.
Apparatus
A term usually used by firefighters describing a piece of equipment, usually a company vehicle.Fire engines, trucks, tankers, and combinations; can also refer to other equipment such as the SCBA.
APW or (PW or Can)
Air-pressurized water fire extinguisher, partially filled with water and then pressurized with an air pump; popular in the US in the 2 1/2-gallon size, rated 2A.
Aqueous Film-Forming Foam (AFFF) (Foam)
(pronounced "A-Triple-F", also called "Class A") bubbles that act as surfactant to coat and penetrate ordinary fuels (e.g., wood, paper) to prevent them from burning at normal temperatures; also used on Class B" (oil/gasoline) fires to spread a non-volatile film over the surface of the fuel. Applied using eductor or Compressed air foam system (CAFS) and pumped through fire hose to a foam nozzle (or sometimes a less-effective fog nozzle).
Arson
The crime of maliciously (or perhaps recklessly) setting fire to property. Punishable in various degrees, depending upon the circumstances.
Attack (Brush Truck)
Small fire truck outfitted for wildland fire. Also called a Type 6 Engine.
Attack Hose
(Attack Line) a use classification of a fire fighting hose connected to output of a pump or other pressure source (e.g., gravity). Fire hose used to apply water or other fire fighting agent directly to a fire or burning substance. Typically of 2 1/2 inches (65 mm) diameter or less.
Attic Ladder
Narrow, collapsible ladder used to access an attic space via a scuttle hole, which are often found in closets and other narrow passages. Also known as a closet ladder.
Authority Having Jurisdiction (or AHJ)
Organization or agency with legal authority over a given type of incident (e.g, fire, EMS, SAR, arson, HAZMAT); may change or overlap as incident changes, as where fire becomes arson investigation once danger is over, or Motor Vehicle Accident becomes police business after vehicle extrication, fire, and HAZMAT issues are complete.
Autoextended Fire
Structure fire that has gone out a window or other opening on one floor and ignited materials above, on another floor or other space (attic, cockloft).
Automatic Sprinkler
System of valves and pipes for automatically directing water to a fire when it is detected. May be normally pressurized with water (wet") or with air ("dry") depending upon the application. When a sprinkler-head (or sensor) detects fire/heat the valve opens releasing the water (hopefully onto the fire).
Available Flow
Total amount of water that can be put on a fire, depending upon water supply, pump size, hoses, and distance to the fire. IC must assess available flow to determine whether additional apparatus or streams are required. See Fire flow requirement.
Backdraft
A fire phenomenon caused when heat and heavy smoke (unburned fuel particles) accumulate inside a compartment, depleting the available air, and then oxygen/air is re-introduced, completing the fire triangle and causing rapid combustion.
Bank Down
What the smoke does as it fills a room, banks down to the floor, creating several layers of heat and smoke at different temperatures -- the coolest at the bottom.
Basement Fire(Cellar fire)
Basement fires are difficult to attack directly because firefighters have to pass through the hot gasses and smoke accumulated on the basements ceiling to gain access to the fire. Basements typically do not have good emergency egress points, adding to the danger.
Bed Ladder
The non-extending section of an extension ladder.
Boiling Liquid Expanding Vapor Explosion (BLEVE)
Explosion of a pressure tank containing an overheated material when the vapor expansion rate exceeds the pressure relief capacity (e.g., steam boiler or LPG tank). If the contents are flammable, the rapidly released vapor may react in a secondary fuel-air explosion.
Booster Hose
Small-diameter fire hose (3/4-1 inch), often carried on booster reel, preconnected to pump of an engine (and the booster tank) for putting out small fires near the truck without having to connect to a fire hydrant; easily recovered with a motorized reel. Booster hose is also used for High Pressure Fog (HPF) applications.
Box (Alarm)
Originally, a mailslot containing a notecard with a pre-planned response to an incident type. For example, a reported structure fire on Some Road would be tagged with Box 6; the notecard in Box 6 would contain the list of apparatus from various fire stations that should be dispatched to that incident. Assigning Boxes to areas (or even specific structures) significantly facilitated the process of getting the right tools to the right place on the initial dispatch, and helped eliminate the guesswork of which department has what on the fire scene. Boxes later evolved to contain escalation procedures - on the "2nd alarm", the Box would contain the next group of apparatus from various fire stations etc. Modern CAD systems now abstract the Box Alarm concept and allow box definitions to be triggered based on arbitrary geographic area, time of day, incident type, weather and any other pre-planned situation. For a given hydranted area the "Summer" box will contain the usual response of Engine Truck and Rescue companies. In the winter, however, the box may be modified (automatically or manually) to include Water Tankers on the initial dispatch to handle the case of frozen hydrants.
Brush Truck (Attack)
Small fire truck outfitted for wildland fire. Also called a Type 6 Engine.
Bunker Gear (Turnout Gear)
Colloquial term for protective pants and boots kept near a firefighters bunk (cot) for rapid deployment; more modernly includes firefighting jacket. Basis for command to Bunker up!" in preparation for hazardous duties. May also refer to entire protective clothing ensemble.
Charged Line
Fire hose under pressure from the pump at the engine.
Chimney Fire
Fast and intense fire in a chimney flue in which accumulated creosote and other combustion byproducts ignite.
Class A, B, C, D, K
Classes of fire extinguisher and corresponding type of fire they extinguish.
- Class A – Ordinary combustibles such as but not limited to paper, wood, and plastics.
- Class B – Flammable liquids such as but not limited to gasoline, motor oil, and diesel fuel.
- Class C – Energized electrical equipment.
- Class D – Flammable metals.
- Class K – Cooking oils.
Closet Hook
Pike pole under 5 ft long.
CO2 Extinguisher
Fire extinguisher that releases carbon dioxide gas to smother and cool a fire, such as a flammable liquid.
Cockloft
Structural space above ceiling and below rafters, often connecting adjacent occupancies and permitting fire to spread laterally, often unseen.
Collapse zone
The area around a structure that would contain debris if the building were to collapse.
Combination Nozzle
A low pressure Fog Nozzle (usually 120 to 150 lbf/in² or 820 to 1030 [[kilopascal|kPa)) that can be adjusted to produce a near straight stream. Also commonly referred to as a Taskforce Tip (TFT).
Company
Two or more firefighters organized as a team, led by a fire officer, and equipped to perform certain operational functions. Compare with platoon and unit.
Compartment Fire
An Isolated" fire or a fire which is "boxed in" or "closed off" from the rest of the structure. An example of this is a fire in a room where all the windows and doors are closed preventing the fire from spreading to other rooms.
Complex
Two or more individual incidents located in the same general area which are assigned to a single incident commander or unified command.
Cross Lay
Arrangement of hose on a pumper such that it can be quickly unloaded from either side of the apparatus; often pre-connected to a pump outlet and equipped with a suitable nozzle.
County (911)
See dispatch
Dead Lay
A load of hose on a pumper, but not connected to a pump outlet. Often used for larger supply lines.
Deck Gun
A master stream device mounted to top deck of pumper.
Deluge Gun
A master stream device that can be positioned on the ground based on the need of the incident commander.
Deluge System
Type of sprinkler system in which sprinkler heads do not have individual valves, and the water (or other extinguishing agent) is disbursed from all sprinkler heads simultaneously when a central (or zoned) valve is triggered by a sensor (or manually). Typically reserved for industrial areas where rapid fire spread must be prevented at the cost of damaging non-burning materials.
Direct Attack
Putting the wet stuff on the red stuff." A form of fire attack in which hoses are advanced to the fire inside a structure and hose streams directed at the burning materials.
Discharge
An outlet or outlets on fire pumps that allows water to flow out of the pump to the fire.
Dispatch (911 0r County)
Refers to person or place designated for handling a call for help by alerting the specific resources necessary.
Double Female
Firehose adapter for connecting two male" couplings together; may also adapt different sizes on either side.
Double Male
Hose coupling adapter with two male-threaded connectors back-to-back; used for connecting two female couplings together.
Drafting
Using a suction pump to lift water from below the pump such as lakes or ponds. Using a semi-rigid suction hose, typically to fill a portable reservoir that has other suction pumps (to relay) or siphon hoses running downhill to their nozzles.
Drills
Training during which an emergency is simulated and the trainees go through the steps of responding as if it were a real emergency.
Dry Chemical
A fire extinguishing agent. It works by breaking the chemical chain reaction in the fire tetrahedron".
Dry Hydrant
A fire hydrant with a valve located at the bottom of the barrel, near the water main. The barrel of the hydrant remains dry until used. The prevents the hydrant from freezing in sub-zero temperatures. A dry hydrant is also an unpressurized pipe that can be used to draft water from a pond or lake.
Dry Sprinkler
A sprinkler system having pressurized air (rather than water) in the distribution pipes until a heat-activated sprinkler head opens and releases the pressure, which opens a water valve (and possibly an accelerator valve) to flow water to the open head; used where the protected premises are not heated during freezing temperatures or where pressurized water in overhead sprinkler pipes could create another hazard.
Eductor
Suction device operated by hose pressure to pull fluid from a reservoir and mix it with the hose stream; often used to add foaming or other materials to water streams.
Electrical Fire
A fire in which the primary source of heat is electricity, resulting in combustion of adjacent insulation and other materials; may be hazardous to attempt to extinguish using water.
Elevator Key
Control panel override key to take elevator car to desired floor. May also refer to special tool used to open elevator shaft-protection doors from outside.
EMS
Emergency medical service(s).
Encapsulated Suit
HAZMAT protective clothing used with SCBA inside the suit to protect a firefighter (HAZMAT technician) from gaseous contaminants. Also known as a Gas Suit.
Engine
A truck outfitted for firefighting, specifically one outfitted to pump water. Generally, vehicles outfitted to pump water are called engines, while those which do not pump water (ladder trucks, tankers, rescues, for example) are not. Many rural fire engines carry a reservoir of water to pump, and use drafting and tankers to obtain further supply. Historically, an engine" was a machine that only pumped water.
Engine Company
A group of firefighters assigned to an apparatus with a water pump and equipped with firehouse and other tools related to fire extinguishment.
Engine House
[archaic] A firehouse housing an engine company.
Engine Pressure
The pressure in a fire hose measured at the outlet of the pump.
Enhanced 9-1-1
Electronic system for automatic correlation of physical telephone lines with information about the location of the caller -- a useful tool for dispatchers when the caller has an emergency but cannot speak.
Evacuation
Removal of personnel from a dangerous area, in particular, a HAZMAT incident, burning building, or other emergency. Also refers to act of removing firefighters from a structure in danger of collapsing.
Evolution
Uniform sequence of practiced steps by squad carrying out common tasks such as selection and placement of ladders, stowing hoses in hose bed, putting hoses and tools into service in particular patterns; intended to result in predictability during emergencies.
Exposure
Property near fire that may become involved by transfer of heat or burning material from main fire, typically by convection or radiation. May range from 40 feet to several miles, depending on size and type of fire or explosion.
Extension Ladder
A 20-60 foot ladder with one or more movable sections that extend beyond a base section, typically using a halyard rope and pulley mechanism for lifting and locking cams to latch the moving sections at a selected height.
Extinguisher
Device containing fire suppressant, often pressurized to expel suppressant when triggered by operator or an automatic release mechanism. Important to properly select type of extinguisher appropriate to type of material burning (wood, grease, electrical, etc). May be portable or permanently installed for special suppression purposes, such as fires in aircraft engines, restaurant exhaust hoods, or computer rooms.
Extrication
Removal of a trapped victim such as a vehicle extrication, confined space rescue, or trench rescue; sometimes using hydraulic spreader, Jaws of Life, or other technical equipment.
FAST (or F.A.S.T. RIT)
Firefighter Assist and Search Team (also called Rapid Entry Team or Rapid Intervention Team) firefighters assigned to stand by for rescue of other firefighters inside a structure; an implementation to support the Two-in, two-out rule; may have specialized training, experience and tools.
Fire Department Connection (FDC)
Location in which pumping apparatus hooks to a buildings standpipe and or sprinkler system. Usually a 3 female connection.
Fire Alarm Control Panel
System for receiving and announcing location of fire based upon input from smoke, flame or heat detectors, or manual call points or pull stations.
Fire Department Keys
Special keys provided to firefighters to access a lockbox, located on some commercial buildings, containing additional keys required for entry or other safety features.
Fire Escape
A building structure arranged outside to assist in safe evacuation of occupants during an emergency; may connect horizontally beyond a fire wall or vertically to a roof or (preferably) to the ground, perhaps with a counter-weighted span to deny access to intruders.
Fire Extinguisher
See Extinguisher above.
Fire Flow
The amount of water being pumped onto a fire, or required to extinguish a hypothetical fire. A critical calculation in light of the axiom that an ordinary fire will not be extinguished unless there is sufficient water to remove the heat of the fire.
Fire Hazard
Materials, structures or processes that may result in creating a fire, permitting a fire to grow undetected, or preventing people from escaping a fire.
Fire Hydrant
See hydrant.
Fire Hydraulics
The study of pumps, hoses, pipes, accessories and tools for moving water or other extinguishing agents from a water supply to a fire.
Fire Load (Btu/sq ft)
An estimate of the amount of heat that will be given off during ordinary combustion of all the fuel in a given space; e.g., a bedroom or a lumberyard.
Fire Marshal
Administrative and investigative office for fire prevention and arson investigation.
Fire Prevention
Fire safety; standards for minimizing fire hazards.
Fire Station Alert System
Fire department dispatching system using radio controls to activate remote signals at designated fire stations and to transmit emergency information via audio or digital channels.