Fire glossary
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39 entries in the Fire glossary beginning with "H"
Halligan tool (or "Hooligan")
Forcible entry tool with a pointed pick and a wedge at right angles on one end of a shaft and a fork or cat's paw at the opposite end. Used in combination with maul or flat-headed axe for forcing padlocks, doors and windows. Based upon original design by Hugh Halligan of FDNY. Forms the irons" when nested with a flathead axe. Various shaft lengths provide mechanical advantage. Derived from the claw tool (fork and hook).
Chemical gas fire extinguishing or liquid agent for diminishing the combustion reaction rate by acting as a thermal ballast; used mainly in closed computer rooms, aircraft, and other high-value installations where corrosive chemicals or water extinguishers are judged inappropriate. Effective at low concentrations (5%) as compared with CO2 (34%). Being phased out with suitable replacements in most applications, with very restricted exemptions, due to international environmental concerns with this and other CFCs.
Utility rope for raising or lowering moving parts of extension ladder.
Hand crew
A number of individuals that have been organized and trained and are supervised principally for operational assignments on an incident. In the United States, a typical hand crew is 20 in number.
Hard Line
A smaller hose about one inch in diameter used by firefighters to clean apparatus.
Hard suction hose
Non-collapsible sections of hose, usually 10 feet long, used when drafting.
A source of danger of personal injury or property damage; fire hazard refers to conditions that may result in fire or explosion, or may increase spread of an accidental fire, or prevent escape from fire. Under worker safety and health regulations, employers have a general duty to provide a workplace free of hazards. See also fire prevention, and HAZMAT.
Hazardous materials, including solids, liquids, or gasses that may cause injury, death, or damage if released or triggered.
Head of a fire
The most rapidly spreading portion of a fire's perimeter, usually to the leeward or up slope.
Heavy fuels
Fuels of large diameter such as snags, logs, large limb wood, which ignite and are consumed more slowly than flash fuels.
A natural or improved takeoff and landing area intended for temporary or occasional helicopter use, typically in remote areas without other access.
A fire crew trained to use helicopters for initial attack, and to support large fires through bucket drops and the movement of personnel, equipment and supplies.
Higbee cut (Higby cut'
A tapered thread termination in a firehose coupling for avoiding cross-threading, the location of which is indicated by a notch cut into a single lug on a hose coupling. If the notches are aligned on mating couplings, the Higbee cuts are aligned and the threads will immediately engage when the swivel fitting is turned.
High Pressure Fog (HPF)
A suppression technique consisting of finely atomized water droplets at several hundred pounds per square inch of pressure. By far, one of the most efficient suppression techniques available. Advantages include a *very* high conversion rate, unmatched atmospheric cooling and control of thermal layers, very little wasted water (and consequent water damage), and the ease of managing a small diameter booster line (defined above) during application. Disadvantages are lack of distance, lack of penetration into various materials, and high risk of burns to the attack crew. HPF is quite popular in Europe, but was discarded in the U.S. due to different building construction and the resulting increase in disadvantages.
High-pressure system
A supplemental pump system used to pressurize the water supply, sometimes used during a large fire, or whenever more than one hydrant is being used.
High-rise building
Any building taller than three or four stories, depending upon local usage, requiring firefighters to climb stairs or aerial ladders for access to upper floors.
High-rise pack
A shoulder load of hose with a nozzle and other tools necessary to connect the hose to a standpipe.
High-rise pack
Hose bundle prepared for carrying to a standpipe in a high-rise building, usually consisting of 50 or more feet of 1 3/4-inch hose and a combination nozzle.
Forged steel hook at end of insulated pole of varying lengths; used for piercing and pulling building materials away from walls and ceilings. Similar to nautical gaff hook. Short hook with a pointed tip is a pike pole; longer hook on a San Francisco hook; two offset hooks on either side of tip is a universal hook; long p-shaped hook is a Boston rake for pulling plaster and lath; short hook with claw on opposite side of tip is either a gypsum hook or the narrower ceiling hook; pike pole with a short handle is a somewhat useless closet hook.
Flexible conduit for moving liquids under pressure; made of various materials including cotton, rubber or plastic (such as PVC); construction may be braided, woven, wrapped or extruded, often in layers (liner and jacket); hose construction and size differs according to its intended use (e.g., hard suction, attack, forestry, booster); typically stocked in standard lengths and coupled together with standardized fittings. See hose coupling.
39 entries in the Fire glossary beginning with "H"

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