Glossary of Fire Department Terms

Common terms used by fire departments, EMS, and emergency management, explained in plain language.

Back to FAQ

A

Accountability (personnel accountability, accountability system, passport system): A system for tracking every firefighter at an emergency scene. Tags, boards, or electronic systems ensure everyone is accounted for, which is especially critical when conditions change rapidly.
Act 101 (PA) (act 101, death benefits act, line of duty death benefit): Pennsylvania's Emergency and Law Enforcement Personnel Death Benefits Act. It pays a one-time death benefit to the surviving spouse, minor children or parents of a firefighter, ambulance or rescue squad member, or law enforcement officer killed in the line of duty. Workers' compensation is a separate benefit.
Act 172 (PA) (act 172, volunteer tax credit): A Pennsylvania law allowing municipalities to offer active volunteer firefighters and EMS personnel a credit against their property tax or earned income tax. Adoption is optional for each municipality and the amount is set locally, so what it is worth depends on where you live. Volunteers must meet an activity threshold set by the department.
AED (automated external defibrillator, defibrillator): Automated External Defibrillator. A portable device that checks heart rhythm and can deliver an electric shock to restore a normal heartbeat during sudden cardiac arrest. Found in many public buildings, and designed for use by anyone, not just medical professionals.
AFCI (arc fault circuit interrupter, arc fault breaker): Arc Fault Circuit Interrupter. A circuit breaker that detects dangerous electrical arcs (sparks) in wiring and shuts off power before they can start a fire. Required in bedrooms and living areas in newer homes.
Air Pack (air tank, breathing air): Common name for an SCBA (Self-Contained Breathing Apparatus). The air tank, mask, and regulator firefighters wear to breathe in smoke-filled or toxic environments.
Alarm (Levels) (box alarm, second alarm, third alarm, general alarm, multiple alarm fire, working fire): A system for escalating emergency response. A "first alarm" is the initial dispatch. A "second alarm" or "third alarm" calls for additional units and personnel. A "general alarm" calls all available resources. Higher alarms mean a bigger emergency.
ALS (advanced life support): Advanced Life Support. A higher level of emergency medical care provided by paramedics, including cardiac monitoring, IV medications, advanced airway management, and other interventions beyond basic first aid.
Ambulance (medic unit, rescue ambulance, bus): A vehicle equipped to transport sick or injured patients to a hospital while providing emergency medical care en route. Can be BLS (basic) or ALS (advanced) depending on the crew and equipment.
Annunciator Panel (fire alarm panel, FACP, alarm panel): A wall-mounted display in a building's lobby that shows firefighters which zone or floor triggered a fire alarm. Helps crews quickly locate the source of an alarm in large buildings.
Apparatus (fire apparatus, rig): Any fire department vehicle, including engines, trucks, tankers, and rescue vehicles.
Arson (arson investigation, incendiary fire): The crime of intentionally setting fire to property. Arson investigation is conducted by fire marshals, fire investigators, or law enforcement to determine if a fire was deliberately set.
Attack Line (handline, hose line, lead line): A hose line used to directly fight a fire. Common sizes are 1-3/4 inch for interior residential fires and 2-1/2 inch for larger or commercial fires.
Autoignition Temperature (auto ignition, self-ignition temperature): The temperature at which a material will catch fire on its own, without a flame or spark touching it. Understanding this helps explain why fires can start in attics, near hot equipment, or from overheated materials.
Automatic Aid: An agreement where neighboring departments are automatically dispatched to each other's calls without needing a specific request, unlike mutual aid, which requires the incident commander to ask for help.

B

Backdraft (back draft): A sudden, explosive fire event that occurs when oxygen is introduced to a very hot, oxygen-starved room, for example, when a door or window is opened. Backdrafts are extremely dangerous to firefighters and are one reason ventilation must be carefully controlled.
Backfire (back burn, burnout): A fire intentionally set ahead of an advancing wildfire to remove fuel in its path, creating a firebreak. Used as a last-resort tactic in wildland firefighting.
BLS (basic life support): Basic Life Support. The level of emergency medical care provided by EMTs, including CPR, bleeding control, splinting, oxygen administration, and basic patient assessment. Does not include medications or advanced procedures.
Blue Light (PA) (blue light permit, courtesy light): In Pennsylvania, volunteer firefighters may equip one personal vehicle with up to two flashing or revolving blue lights, for use when responding to an emergency call. Blue lights are a courtesy request to yield. They do not give the driver any legal authority to violate traffic laws.
Booster Line (booster reel, reel line): A small-diameter rubber hose (usually 3/4 or 1 inch) stored on a reel on a fire engine. Good for small outdoor fires such as brush, trash, or a dumpster. It is not enough for a house fire.
Brush Truck (brush engine, wildland engine, grass rig): A smaller, more agile fire vehicle designed for fighting wildfires, brush fires, and grass fires. Often 4-wheel drive to handle rough terrain where full-size engines cannot go.
BSI (body substance isolation): Body Substance Isolation. The protective measures first responders take to avoid contact with blood and other bodily fluids, including gloves, eye protection, and gowns.
BTU (british thermal unit): British Thermal Unit. A measure of heat energy. One BTU is the heat needed to raise one pound of water by one degree Fahrenheit. Modern furnishings produce far more BTUs than older materials, which is why today's house fires burn hotter and faster than in past decades.

C

Captain: A fire department officer rank, typically in charge of a single company (engine, truck, or rescue). Captains supervise their crew, make tactical decisions on scene, and report to higher-ranking officers.
Carbon Monoxide (CO) (CO, carbon monoxide): A colorless, odorless, poisonous gas produced by incomplete combustion of fuels. CO detectors are the only way to detect it in your home. Sources include furnaces, water heaters, fireplaces, generators, and cars idling in garages.
Cause and Origin (fire investigation, origin and cause): The investigation process to determine where a fire started (origin) and what caused it (cause). Conducted by fire investigators or fire marshals after every significant fire.
CERT (community emergency response team): Community Emergency Response Team. A FEMA program that trains civilians in basic disaster response skills (fire suppression, search and rescue, first aid) so they can help their communities during emergencies.
Chain of Command: The organizational structure that defines who reports to whom at an emergency scene. A clear chain of command ensures orders flow efficiently and everyone knows their role.
Chimney Fire (creosote fire, flue fire): A fire inside a chimney caused by creosote buildup igniting. Signs include a loud roaring sound, dense smoke, and intense heat from the chimney. Annual chimney cleaning and inspection prevents chimney fires.
Cistern (water cistern, fire cistern): An underground or above-ground water storage tank used as a fire water supply in rural areas without hydrants. Some homeowners install cisterns specifically for fire department use.
Class A Fire (ordinary combustibles fire): A fire involving ordinary combustibles: wood, paper, cloth, rubber, and many plastics. The most common type of fire. Extinguished with water or a Class A/ABC extinguisher.
Class B Fire (flammable liquid fire): A fire involving flammable liquids or gases: gasoline, oil, propane, paint, or cooking grease (except in deep fryers). Extinguished with foam, CO2, or a Class B/ABC extinguisher. Never water.
Class C Fire (electrical fire): A fire involving energized electrical equipment: appliances, wiring, breaker panels, or power tools. Once the power is disconnected, it becomes a Class A or B fire. Use a CO2 or ABC extinguisher. Never water on live electrical.
Class D Fire (metal fire, combustible metal fire): A fire involving combustible metals like magnesium, titanium, or sodium. Rare in homes, more common in industrial settings. Requires special dry powder extinguishing agents. Water can make these fires explode.
Class K Fire (kitchen fire, grease fire, cooking oil fire): A fire involving cooking oils and fats, particularly in commercial kitchens with deep fryers. Requires a wet chemical extinguisher (Class K). This is why you never throw water on a grease fire. It causes a violent flare-up.
Close Before You Doze (close the door, close your door): A fire safety campaign reminding people to close bedroom doors before sleeping. A closed door holds back fire and smoke, and keeps the air behind it survivable for far longer than an open room.
Combination Department (combo department): A fire department staffed by both career (paid) and volunteer firefighters. Many departments that were once fully volunteer have transitioned to combination departments as volunteer numbers decline.
Command Post (CP, incident command post): The location at an emergency scene where the Incident Commander manages operations. Usually identified by a vehicle with flashing green lights or a specific sign.
Conduction: Heat transfer through direct contact between materials. In a fire, conduction spreads heat through walls, metal pipes, and wiring, which is why fires can spread to rooms that seem far from the flames.
Convection: Heat transfer through the movement of hot air and gases. Convection is why smoke and heat rise and why upper floors catch fire before lower ones. It's also why you should crawl low under smoke. The air near the floor is cooler and more breathable.
CPR (cardiopulmonary resuscitation, hands-only CPR): Cardiopulmonary Resuscitation. An emergency procedure combining chest compressions and rescue breathing to maintain blood flow when someone's heart stops. Hands-only CPR (compressions without breaths) is recommended for untrained bystanders.
Cribbing: Short lengths of wood (usually 4x4 or 2x4) stacked to stabilize vehicles, structures, or heavy objects during rescue operations. Creates a stable platform to prevent shifting while crews work to free trapped patients.

D

Defensive Attack (defensive operations, surround and drown): A firefighting strategy where crews fight the fire from outside the building, focusing on preventing it from spreading to neighboring structures. Used when conditions are too dangerous to enter, or when the building is already lost.
Dispatch / 911 Center (dispatch, 911 center, PSAP, dispatcher, public safety answering point): The facility and staff that receive 911 calls, determine the appropriate response, and alert fire, EMS, and police units. Also called a PSAP (Public Safety Answering Point).
Drafting (draft, drafting water): The process of drawing water from a static source (pond, lake, river, swimming pool) using a fire engine's pump and a hard suction hose. Essential in rural areas without hydrants.
Drop Tank (portable pond, portable water tank, dump tank): A large portable container set up at a fire scene to hold water delivered by tanker trucks. Engines then draft from the drop tank, creating a continuous water supply in areas without hydrants.
Dry Chemical Extinguisher (ABC extinguisher, multipurpose extinguisher): A fire extinguisher that uses a powdered chemical agent (typically monoammonium phosphate) to smother fires. ABC-rated dry chemical extinguishers are the most common type for homes because they work on ordinary, liquid, and electrical fires.
Dry Hydrant: A permanent pipe installed into a pond, lake, or stream that allows firefighters to quickly connect and draft water without setting up portable equipment. Common in rural areas to speed up water supply operations.

E

EMS (emergency medical services): Emergency Medical Services. The system that provides emergency medical care, including ambulance transport, paramedic services, and first response.
EMT (emergency medical technician): Emergency Medical Technician. A certified responder trained to provide basic emergency medical care including CPR, bleeding control, splinting, and patient assessment.
Engine (Fire Engine) (fire engine, pumper, engine company): A fire department vehicle that carries water, hose, and a pump. Its primary purpose is to deliver water to a fire. Also called a "pumper." Engines carry their own water and several sizes of hose.
EOC (emergency operations center): Emergency Operations Center. A central facility where government officials and emergency managers coordinate response to large-scale disasters. Manages resource allocation, public information, and multi-agency coordination.
Evacuation (evacuate, mandatory evacuation, voluntary evacuation): The organized movement of people from a dangerous area to a safe location. Can range from evacuating a single building to evacuating an entire region during a natural disaster.
Exposure Protection (exposure, protecting exposures): The work of keeping a fire from spreading to nearby buildings. Crews wet down the houses and barns next to the one that is burning, so the heat coming off it does not set them alight too.
Extrication (vehicle extrication, rescue extrication, entrapment): The process of freeing a person trapped in a vehicle, machinery, or collapsed structure. Firefighters use hydraulic tools (Jaws of Life), saws, and other equipment to cut, spread, and remove material around the patient.

F

FAST Team (firefighter assist and search team, RIT, rapid intervention team, rapid intervention crew): Firefighter Assist and Search Team. A crew standing by at a working fire specifically to rescue firefighters if they become trapped or injured. Also known as RIT (Rapid Intervention Team).
FEMA (federal emergency management agency): Federal Emergency Management Agency. The U.S. government agency responsible for coordinating disaster response, recovery, and preparedness. Provides training, grants, and resources to local fire and emergency services.
Fire Alarm System (fire alarm, alarm system, fire detection system): A network of devices in a building that detects fire and warns the people inside. It includes smoke detectors, heat detectors, pull stations, and horns. Commercial systems also notify the fire department directly.
Fire Chief (chief): The highest-ranking officer in a fire department. Responsible for all department operations, personnel, training, budgeting, and community relations. In volunteer departments, the chief is typically elected by the membership.
Fire Code (fire safety code, building fire code): Laws and regulations that govern fire safety in buildings, including requirements for sprinklers, alarms, exits, fire-resistant construction, and occupancy limits. Enforced through inspections by fire marshals or code enforcement officers.
Fire Department Connection (FDC) (FDC, siamese connection, fire department siamese): A pipe connection on the outside of a building where firefighters can pump water into the building's sprinkler or standpipe system to boost water pressure during a fire.
Fire Door (fire-rated door): A door built and rated to hold back fire for a set length of time, shown on a label on the door edge. Fire doors are designed to close automatically and contain fire and smoke within sections of a building, giving occupants more time to escape.
Fire Escape Plan (escape plan, home fire escape plan, exit plan, family escape plan): A household plan that maps two ways out of every room, designates a meeting place outside, and is practiced regularly. The NFPA recommends practicing your escape plan at least twice a year.
Fire Extinguisher (extinguisher, portable extinguisher): A portable device used to put out small fires. Rated by fire class (A, B, C, D, K). For homes, a 2A:10B:C rated extinguisher on each floor is recommended. Remember PASS: Pull the pin, Aim at the base, Squeeze the handle, Sweep side to side.
Fire Investigation (fire investigator, origin and cause investigation): The systematic process of examining a fire scene to determine the origin (where it started) and cause (what started it). All fires are investigated. The responding department handles most of them, and serious fires go to dedicated investigators or the state fire marshal.
Fire Lane (no parking fire lane): A designated area near a building that must be kept clear for fire department access. Fire lanes are marked with signs, painted curbs, or both. Parking in a fire lane is illegal and can delay emergency response.
Fire Load (fuel load): The total amount of combustible material in a given area. Modern homes have a much higher fire load than older homes due to synthetic furnishings, plastics, and petroleum-based materials, which is why fires today burn faster and hotter.
Fire Marshal (fire marshal, state fire marshal): An official responsible for fire investigation (determining fire causes), fire code enforcement, building inspections, and public fire safety education. May be a local, county, or state position.
Fire Police: Specially trained volunteer members of a fire department who direct traffic, control crowds, and secure the scene at emergencies. In Pennsylvania fire police are appointed and sworn through the municipality, and the Vehicle Code requires drivers to obey any appropriately attired person authorized to direct traffic.
Fire Prevention Week (national fire prevention week): An annual NFPA campaign held in October, marking the anniversary of the Great Chicago Fire. Fire departments run community education, open houses, and school visits during the week.
Fire Sprinkler System (sprinkler system, sprinklers, fire sprinklers, residential sprinklers): A network of water pipes and sprinkler heads installed in a building that automatically activates when heat from a fire is detected. Only the sprinkler heads nearest the fire activate. They don't all go off at once like in movies. A sprinkler usually controls a fire while it is still small, long before we arrive.
Fire Station (firehouse, fire hall, station house): The building where fire apparatus, equipment, and personnel are housed. Also serves as a community hub for meetings, training, and public events. Also called a firehouse.
Fire Tetrahedron (fire triangle, fire elements, combustion triangle): The four elements required to sustain fire: heat, fuel, oxygen, and a chemical chain reaction. Removing any one element extinguishes the fire. An evolution of the simpler "fire triangle" (heat, fuel, oxygen).
Fire Wall (firewall, fire separation wall, party wall): A wall built with fire-resistant materials designed to prevent fire from spreading between sections of a building or between adjacent buildings. Common in townhouses, row homes, and commercial structures.
Fire Watch: A person assigned to continuously monitor a specific area for fire hazards, typically required when a building's fire protection system is out of service, or during hot work (welding, cutting) operations.
Firefighter I / Firefighter II (FF1, FF2, firefighter 1, firefighter 2): The national certification levels for firefighters. Firefighter I is the entry level and covers basic skills such as protective equipment, ladders, hose, and search and rescue. Firefighter II covers advanced skills. The same certifications apply to volunteer and career firefighters.
Flashover: The point in a fire when all combustible materials in a room simultaneously ignite due to radiant heat. Everything in the room ignites at once. Flashover is unsurvivable. This is why "get out" is always the right answer.
Flashpoint (flash point): The lowest temperature at which a liquid gives off enough vapor to ignite briefly when exposed to a flame. Gasoline gives off ignitable vapor far below freezing, which is why it's so dangerous. It can ignite even in extreme cold.
Forcible Entry: Techniques firefighters use to gain access to a locked or blocked building during an emergency, using tools like Halligan bars, axes, and hydraulic tools. Necessary when occupants may be trapped or fire is spreading.

G

GFCI (ground fault circuit interrupter, GFI): Ground Fault Circuit Interrupter. An electrical outlet that automatically shuts off power when it detects current flowing through an unintended path (like water). Required in kitchens, bathrooms, garages, and outdoor outlets. The "test" and "reset" buttons should be tested monthly.
Golden Hour: The critical first hour after a severe traumatic injury, during which prompt medical treatment dramatically improves survival odds. This is why rapid EMS response and quick transport to a trauma center matter so much.

H

Halligan Bar (halligan, hooligan bar, the irons): A heavy steel tool with a forked end, a blade, and a pick. The most versatile forcible entry tool a firefighter carries. Used to pry open doors, break locks, breach walls, and perform many other tasks. Often paired with a flathead axe (together called "the irons").
HAZMAT (hazardous materials, hazmat incident, hazmat response): Hazardous Materials. Any chemical, biological, radiological, or physical substance that poses a risk to health, safety, or the environment. Fire departments respond to hazmat incidents including chemical spills, gas leaks, and suspicious substances.
Heat Detector (thermal detector, rate-of-rise detector, fixed temperature detector): A fire detection device that activates when air temperature reaches a set point, or when temperature rises rapidly. Used where a smoke detector would go off for no reason: garages, kitchens, attics, and boiler rooms.
Hydrant (fire hydrant): A connection point in a water distribution system where firefighters can connect hoses to access pressurized water. Not every area has them. Rural departments haul water in with tankers instead.

I

ICS (incident command system, incident command): Incident Command System. A standardized management structure used at emergency scenes nationwide. Defines clear roles (command, operations, planning, logistics, finance) so that multiple agencies can work together effectively. Required training for all emergency responders.
Incident Commander (IC) (IC, incident commander): The person in charge of managing all operations at an emergency scene. The IC makes tactical decisions, coordinates resources, and communicates with dispatch and incoming units. Usually the first-arriving officer until transferred to a senior officer.
Interior Attack (offensive attack, interior operations, aggressive attack): A firefighting strategy where crews go into the burning building and fight the fire from inside, working the hose lines toward wherever the fire is burning hottest. Used when it is still safe enough to go in and there is a chance to save the building or the people in it.
Ionization Smoke Alarm (ionization detector, ionization alarm): A type of smoke alarm that uses a small amount of radioactive material to detect fast-flaming fires. Better at sensing open flames, but slower to detect smoldering fires. For best protection, use both ionization and photoelectric alarms, or combination alarms.
ISO Rating (ISO score, fire insurance rating, public protection classification): Insurance Services Office rating. A score from 1 (best) to 10 (worst) that evaluates a community's fire protection capability. Factors include the fire department, water supply, and emergency communications. Insurers use the community's rating as one factor in setting homeowner premiums.

J

Jaws of Life (hydraulic rescue tools, extrication tools, spreader, cutter, rescue tools): A brand name that has come to mean any hydraulic rescue tool: the spreaders, cutters, and rams used to free people from crashed vehicles. Powerful enough to cut through steel car frames and pry open crushed doors.
Junior Firefighter (junior member, explorer, fire cadet): A young person (typically ages 14-17) who participates in fire department activities, training, and community events under adult supervision. Junior programs introduce young people to the fire department and prepare them for full membership at age 18.

K

Knockdown (fire knockdown, knock down): The point at which firefighters have reduced a fire's intensity enough that it is no longer spreading. It does not mean the fire is out. Crews still have to find and soak any fire hidden in the walls and ceiling.
Knox Box (key box, key vault, rapid entry system): A small, secure key vault mounted on the outside of a commercial building that holds building keys. Firefighters can open it with a master key, allowing quick entry without forcing doors, saving time and reducing property damage.

L

Ladder Truck (tower truck, aerial, tower ladder, truck company): A fire department vehicle equipped with an aerial ladder or platform for reaching upper floors, ventilating roofs, and performing rescues from height. Also carries ground ladders, saws, forcible entry tools, and ventilation fans.
Lieutenant: A fire department officer rank, typically second-in-command of a company under a captain. Lieutenants supervise crews, lead operations, and step into the captain's role when needed.
Live Burn (burn building, live fire training): A training exercise where a controlled fire is set in an acquired structure or burn building so firefighters can practice with real heat and smoke. They work the hose lines, search rooms, and learn how a fire actually moves.
LOSAP (length of service award program, volunteer pension): Length of Service Award Program. A tax-deferred retirement benefit program for volunteer firefighters and EMS personnel. Municipalities contribute annually to each qualifying volunteer's account, providing a financial incentive for sustained service.

M

Master Stream (deck gun, monitor, deluge gun, ladder pipe): A large-capacity water nozzle mounted on a truck, engine, or portable stand. Used for large fires where hand-held hose lines aren't sufficient, typically in defensive operations.
Mayday (mayday call): An emergency radio call made by a firefighter who is lost, trapped, injured, or running out of air inside a burning building. A Mayday immediately triggers the deployment of the FAST/RIT team for rescue.
MCI (mass casualty incident, mass casualty event): Mass Casualty Incident. Any emergency with more patients than the responding crews can handle the usual way. Could be a bus crash, building collapse, explosion, or chemical release. Triggers triage protocols and mutual aid.
Means of Egress (egress, exit route, escape route): The path of travel from any point inside a building to a public way outside. Includes exit access (corridors, aisles), exits (doors, stairwells), and exit discharge (the area outside the exit). How many a building needs depends on its occupant load, travel distance and occupancy type.
Meeting Place (rally point, meeting point, family meeting place, assembly point): A pre-designated spot outside your home where all family members gather after evacuating during a fire or emergency. Should be a permanent landmark (mailbox, specific tree, neighbor's driveway) a safe distance from the house.
Move Over Law (PA) (steer clear law, steer clear, move over law): Pennsylvania law requiring drivers approaching an emergency response area to move over a lane if they can, and otherwise to slow well below the posted speed limit. It covers emergency vehicles, tow trucks and maintenance vehicles with lights flashing, and any disabled vehicle showing at least two warning signals. Formerly known as the Steer Clear law.
Mutual Aid: A formal agreement between neighboring fire departments to assist each other during emergencies. When one department needs more resources, mutual aid partners respond. Essential for volunteer departments that may need additional personnel for large incidents.

N

NFPA (national fire protection association): National Fire Protection Association. The organization that develops the fire safety codes and standards used throughout the United States, covering things like fire alarms, portable extinguishers and building life safety.
NIMS (national incident management system): National Incident Management System. A nationwide framework established by FEMA for managing emergencies of all sizes. Provides a common language, structure, and set of procedures so that agencies from different jurisdictions can work together seamlessly.

O

Occupancy Type (building occupancy, occupancy classification): A building's classification based on what it is used for: home, store, factory, church, school, and so on. Occupancy type determines fire code requirements, sprinkler needs, occupant loads, and the number of exits required.
Offensive Attack (interior attack, aggressive attack): A firefighting strategy where crews enter the building and aggressively attack the fire from inside. The goal is to save the building and anyone inside. It takes conditions that are still safe enough to enter, and enough people on scene to do it.
Overhaul: The process of searching for and extinguishing hidden fire after the main fire is knocked down. Firefighters open walls and ceilings to ensure fire hasn't spread into concealed spaces. Overhaul prevents the fire from reigniting.

P

PA State Fire Academy (state fire academy, PA fire academy, Lewistown): Pennsylvania's state-funded training institution for firefighters, located in Lewistown, PA. Firefighter I/II, HAZMAT, rescue, and officer training are free to volunteer firefighters, and courses are also held at regional sites around the state.
PAR (personnel accountability report, accountability report): Personnel Accountability Report. A roll call conducted by radio at an emergency scene to confirm all firefighters are accounted for. A PAR is required at regular intervals and immediately after any significant event (collapse, flashover, Mayday).
Paramedic: A healthcare professional trained to provide advanced emergency medical care, including administering medications, starting IVs, interpreting heart rhythms, and performing advanced airway management. Paramedics provide ALS (Advanced Life Support).
PASS (Fire Extinguisher) (pull aim squeeze sweep, fire extinguisher technique): The four-step technique for using a fire extinguisher: Pull the pin, Aim at the base of the fire (not the flames), Squeeze the handle, and Sweep side to side.
PASS Device (Firefighter) (personal alert safety system, motion alarm): Personal Alert Safety System. A device worn by firefighters that emits a loud alarm if the wearer stops moving for approximately 30 seconds. Helps locate a firefighter who is down, trapped, or unconscious in a fire.
Photoelectric Smoke Alarm (photoelectric detector, photoelectric alarm): A type of smoke alarm that uses a light beam to detect smoke particles. Better at sensing slow, smoldering fires (like a cigarette igniting a couch). For best protection, use both photoelectric and ionization alarms, or combination alarms.
Pike Pole: A long pole with a sharp point and hook on the end, used to pull down ceilings, walls, and other materials during overhaul and ventilation. One of the oldest and most basic firefighting tools.
PPE (personal protective equipment, turnout gear, bunker gear, gear): Personal Protective Equipment. The gear worn by firefighters including turnout coat, pants, boots, gloves, hood, helmet, and SCBA (breathing apparatus). A full set of turnout gear costs several thousand dollars and is retired ten years from its manufacture date, or sooner after significant exposure.
Pre-Incident Plan (pre-plan, preplan, pre-fire plan): A document prepared by the fire department detailing a specific building's layout, hazards, water supply, and access points. Helps crews respond more effectively when an emergency occurs at that location.
Primary Search (primary search and rescue): The first, rapid search of a burning building to find and rescue any trapped occupants. Speed is critical. Firefighters move quickly through smoke-filled rooms, checking likely locations (beds, closets, under furniture, near exits).
Probationary Firefighter (probie, rookie, probationary member): A new firefighter serving a trial period (typically 6-12 months) during which they complete basic training and demonstrate competence. Also called a "probie" or "rookie."
Pull Station (fire alarm pull station, manual pull station, fire alarm pull): A manual fire alarm activation device. The red box on the wall with the handle you pull to trigger the building's fire alarm. Usually located near exits and stairwells.

Q

Quint: A fire apparatus that combines five (quint) functions in one vehicle: pump, water tank, hose, aerial ladder, and ground ladders. Provides the versatility of both an engine and a ladder truck.

R

Radiation (Heat) (radiant heat): Heat transfer through electromagnetic waves. The warmth you feel standing near a campfire. In a structure fire, radiant heat can ignite a neighboring building across a gap, with no flame touching it.
Rehab (rehabilitation, rehab area, rehab sector): A designated area at an emergency scene where firefighters rest, rehydrate, cool down, and have their vital signs checked. Working in full gear in extreme heat is hard on the body, and rehab is what prevents heat exhaustion and heart attacks.
Rescue Vehicle (rescue truck, rescue squad, heavy rescue, squad): A fire department vehicle that carries specialized equipment for technical rescue, vehicle extrication, confined space rescue, water rescue, or other non-fire emergencies. May be a heavy rescue (truck-sized) or a light rescue (smaller).
RIT (rapid intervention team, rapid intervention crew, RIC): Rapid Intervention Team. A crew of firefighters standing by at a working fire specifically to rescue other firefighters who become trapped, lost, or injured inside a burning building. When a "Mayday" is called, the RIT deploys immediately. Also known as a FAST Team (Firefighter Assist and Search Team).
Rollover (flameover): The extension of flames across the ceiling of a room as hot gases ignite overhead. A warning sign that flashover is imminent. Firefighters who see rollover know conditions are rapidly deteriorating.

S

Salvage (salvage operations): The work of protecting whatever the fire has not damaged: covering furniture with tarps, getting water out, shutting off utilities. Salvage operations can save homeowners thousands of dollars in additional damage.
SCBA (self-contained breathing apparatus, air pack, breathing apparatus): Self-Contained Breathing Apparatus. The air tank and mask firefighters wear to breathe in smoke-filled environments. Each tank provides roughly 20-30 minutes of air depending on the firefighter's exertion level.
Scene Safety: The first priority at any emergency: making sure the scene is safe for the crew before anyone starts working. Hazards include traffic, downed power lines, structural collapse, hazardous materials, and violent individuals.
Secondary Search: A thorough, methodical search of a building after the fire is controlled, to ensure no victims were missed during the primary search. Conducted in better visibility and conditions than the primary search.
Shelter in Place (sheltering in place): An instruction to stay where you are, close all the windows and doors, and seal any gaps. It is used for chemical spills, gas leaks, and other outdoor dangers, where going outside would put you in more danger than staying put.
Size-Up: The rapid assessment a first-arriving officer makes at an emergency scene: What's happening? What resources do we need? What's our plan of attack? It never stops. Conditions change, and the plan changes with them.
Smoke Alarm (smoke detector, fire alarm, smoke alarm detector): A device that detects smoke and sounds an audible alarm to alert occupants to fire. Install on every level of your home, inside every bedroom, and outside sleeping areas. Test monthly, replace batteries annually (unless sealed), and replace the entire unit every 10 years.
Smoke Inhalation: Injury caused by breathing in toxic smoke and gases during a fire. Smoke inhalation, not burns, is the leading cause of fire deaths. Smoke contains carbon monoxide, hydrogen cyanide, and other lethal gases that can incapacitate in minutes.
Sprinkler Head (fire sprinkler head): An individual component of a sprinkler system that releases water when the surrounding air gets hot enough. Each head works on its own, so only the ones nearest the fire go off.
Staging (staging area): A designated area near an emergency scene where additional units and personnel wait until assigned by the Incident Commander. It keeps the scene orderly and stops crews from wandering off to do their own thing.
Standpipe (standpipe system): A permanently installed pipe in a building that provides water connections on each floor for firefighter hose lines. Common in high-rise buildings, parking garages, and large commercial structures. Similar to a fire hydrant, but inside the building.
Stop, Drop, and Roll (stop drop and roll, stop drop roll): The technique for extinguishing fire on your clothing: Stop where you are (don't run, running fans the flames), Drop to the ground, and Roll back and forth to smother the fire. Cover your face with your hands while rolling.
Strike Team: A set number of resources of the same type (for example, five engines) assembled for a specific assignment. Used in large incidents and mutual aid responses to maintain organizational structure.
Supply Line (supply hose, large diameter hose, LDH): A large-diameter hose (usually 4 or 5 inches) used to bring water from a hydrant, tanker, or other water source to the fire engine at the scene. Different from the smaller attack lines used to fight the fire directly.

T

Tanker / Tender (water tanker, water tender, tanker truck): A fire department vehicle designed to carry large amounts of water to areas without hydrants. Essential in rural firefighting where no municipal water system exists.
Task Force: A combination of different types of resources (for example, two engines and a ladder truck) assembled under one leader for a specific assignment at a large incident.
Thermal Imaging Camera (TIC) (TIC, thermal camera, thermal imager, infrared camera): A handheld device that detects heat signatures through smoke and darkness. In smoke thick enough to blind you, it will still find a person on the floor, show where the fire is burning hottest, and pick up fire hidden inside a wall.
Thermal Layering (heat stratification, smoke layering): The stratification of gases in a burning room. The hottest gases accumulate at the ceiling, while cooler air stays near the floor. This is why you should crawl low under smoke: the air just 12 inches off the floor may be hundreds of degrees cooler.
Transitional Attack: A firefighting strategy that begins with a quick exterior water application (usually through a window) to cool conditions before crews enter the building. Combines the safety of a defensive approach with the effectiveness of an interior attack.
Triage (triage system, START triage): The process of rapidly assessing and sorting multiple patients by severity when there are more victims than resources. Patients are categorized as immediate (red), delayed (yellow), minor (green), or deceased (black) to ensure the most critical patients receive care first.
Two Ways Out (two exits): A core principle of fire escape planning: every room in your home should have two ways to get out, typically the door and a window. If one exit is blocked by fire, you use the other. This is why escape ladders are recommended for upper-floor bedrooms.
Two-In / Two-Out (two in two out, 2-in 2-out): An OSHA safety rule requiring that when two firefighters enter a hazardous atmosphere (like a burning building), at least two fully equipped firefighters must remain outside, ready to rescue them if needed. OSHA adds that nothing in the rule is meant to stop firefighters from performing an emergency rescue before the whole team has assembled.

U

UCC (PA) (uniform construction code, building code): Uniform Construction Code. Pennsylvania's statewide building code. It sets the requirements for smoke alarms, fire sprinklers, fire-resistant construction, and exits in new buildings and major renovations.

V

VEIS (vent enter isolate search): Vent, Enter, Isolate, Search. A firefighting technique for rescuing trapped occupants from a specific room. Firefighters vent a window from outside, enter the room, close the door to isolate it from fire in the hallway, and search for victims.
Ventilation (vertical ventilation, horizontal ventilation, positive pressure ventilation, PPV): The controlled release of heat, smoke, and gases from a burning building. This is why firefighters cut holes in roofs (vertical ventilation) and break windows (horizontal ventilation). It improves visibility and conditions for both occupants and firefighters.
Volunteer Fire Department (volunteer fire company, VFD, volunteer department): A fire department staffed primarily by unpaid volunteers who respond to emergencies from their homes or workplaces when dispatched. Volunteers make up most of the firefighters in the United States and protect the majority of the country's land area.
Volunteer Fire Relief Association (fire relief association, relief association): In Pennsylvania, an organization that manages state and local funds designated for volunteer fire departments. Relief associations receive a share of foreign fire insurance tax revenue, which funds equipment, training, and operational expenses.

W

Water Shuttle (tanker shuttle, water supply operation, water relay): A coordinated operation using multiple tanker trucks to continuously transport water from a distant source to the fire scene. Tankers take turns filling, driving to the scene, dumping into a drop tank, and returning to refill, creating a continuous water supply.
Wildland-Urban Interface (WUI) (WUI, wildland urban interface, urban interface): The zone where developed areas (homes, buildings) meet or intermix with wildland vegetation. These areas face a much higher wildfire risk. Most homes that burn in a wildfire are lit by wind-blown embers rather than by an advancing wall of flame, so the few feet closest to the walls matter most: keep anything that burns away from the house, then thin brush and trees working outward.
Working Fire: A confirmed structure fire with visible flames or heavy smoke that requires a full firefighting effort. A "working fire" designation typically triggers additional resources beyond the initial dispatch.

← Back to Frequently Asked Questions