|
H.A.D. |
Heat actuating devices
thermostatically controlled and used to activate fire equipment, alarms, or
appliances. |
|
H
Clip |
Small metal clips formed like an "H" that
fits at the joints of two plywood (or wafer board) sheets to stiffen the
joint. Normally used on the roof sheeting. |
|
Half life
|
The period of time required for
any radioactive substance to lose half of its strength or reduce by one-half
its total present energy. |
|
Half timber |
Exterior
wall construction having wood frame members exposed and the spaces between
filled with stucco or masonry. |
|
Halligan
tool |
A Halligan bar (also called a Halligan tool
or simply Halligan) is a special tool commonly used in the fire and rescue
service. It was designed by and named after Hugh Halligan, a First Deputy
Fire Commissioner in the New York City Fire Department. The Halligan is a
multipurpose prying tool consisting of a claw (or fork), a blade (or adze),
and a pick, which is especially useful in quickly breaking through many
types of locked doors. The adze or fork end of the tool can be used to break
in through an outward swinging door by forcing the tool between the door and
doorjamb and prying the two apart. Along with a K-tool and the adze or fork
end a lock can easily be pulled. There are many other uses of the Halligan
tool, including vehicle rescue and opening of walls. |
|
Halogenated hydrocarbons |
The compounds formed when the atoms of the halogens replace
the atoms of hydrogen in simple hydrocarbons. Many halogenated hydrocarbons
can be used as extinguishing agents. |
|
Halogens |
The name given to the family of
elements that includes fluorine, chlorine, bromine, and iodine. |
|
Halon |
Halogenated extinguishing agent.
Halon extinguishes fires by inhibiting the chemical reaction between fuel
and oxygen. See tetrahedron. |
|
Halyard |
Rope used with extension ladders
to extend the fly sections. |
|
Handline |
A handline is a small
diameter hose usually used inside a burning structure to directly apply
water on to the fire. Hand lines are usually 1.5 or 1.75 inches in diameter
that can be handled and maneuvered without mechanical assistance. Lines as
large as 2.5 inches in diameter (also called the "deuce and a half") can be
used for heavy fire conditions |
|
Hanger
|
Metal strap used to support the ends of
joists or piping. |
|
Hard
sleeve |
Also called suction hose, these are the
sections of hose which maintain their round shape even a significant vacuum
is applied. These are the short, almost rigid, black hose sections that one
normally sees on the outside of the side of fire apparatus. They are used
when firefighters need to get water from an open source such as a pond or
lake. One end is placed into the water while the other end is connected to
the apparatus. The pump is engaged which creates the suction needed to bring
the water into the pump from where it is distributed to the hose lines or
other apparatus. See hard suction |
|
Hard suction |
A heavy non-collapsible suction
hose used for drafting water from static supply such as lakes, ponds or
swimming pools. |
|
Haunch |
An extension, knee like protrusion of the
foundation wall that a concrete porch or patio will rest upon for support. |
|
Hazard |
Something that is potentially
dangerous or harmful, often the root cause of an unwanted outcome. |
|
Hazard and risk evaluation |
Evaluation of hazard information and the assessment of the relative
risks of a hazmat incident. Evaluation process leads to the development of
Incident Action Plan. |
|
Hazard assessment |
The determination of the lack of safety or
degree of risk based on all integral parts of an exposure situation,
including the characteristics of the chemicals) to which one is exposed and
the conditions that determine degree of exposure. A process used to
qualitatively or quantitatively assesses risk factors to determine incident
operations. |
|
Hazard class |
A group of materials, as designated by the
Department of Transportation, that share a common major hazardous property,
i.e., flammable liquids, explosives gases, oxidizers, radioactive materials,
corrosives, flammable solids, poisonous and infectious substances, and
dangerous substances. One of nine classes of hazardous materials as
categorized and defined by the Department of Transportation in 49 CFR. |
|
Hazard control zones |
The areas at
a hazardous materials incident that are designated based upon the degree
of hazard. These zones are defined as the Hot, Warm and Cold zones. |
|
Hazard evaluation |
The impact
or risk the hazardous substance poses to public health and the
environment. |
|
Hazard ratings
|
A method for
conveying information on the health effects of a chemical, its
flammability potential and reactivity properties, and for conveying
special warnings regarding carcinogenicity, radioactivity, what not to
use in case of fire, etc. The NFPA 704 diamond symbol is such a method
for providing this type information. |
|
Hazardous |
Capable of
posing an unreasonable risk to health and safety. Capable of doing harm. |
|
Hazardous atmosphere |
Any
atmosphere that is oxygen deficient or contains toxic or other type
health hazards at concentrations exceeding established exposure limits.
Also considered to be an atmosphere that may expose personnel to the
risk of death, incapacitation, or the impairment of their ability for
self-rescue, injury, or illness. |
|
Hazardous chemical |
Either a
chemical that can cause chronic or acute harm upon exposure or a
chemical listed in a specific EPA, OSHA, FDA, USDA or DOT regulation. A
chemical for which there is statistically significant evidence, based on
at least one study conducted in accordance with established scientific
principles, that acute or chronic health effects may occur to exposed
employees. Also considered to be any chemical which is caustic,
explosive, flammable, poisonous, corrosive, reactive, or radioactive,
and which requires special care when handling because its presence or
use is a physical or health hazard. |
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Hazardous chemical emergency |
Any
emergency involving a hazardous chemical. |
|
Hazardous material emergency |
An
uncontrolled or unexpected release of a hazardous material. |
|
Hazardous Material
Identification System [HMIS] |
A
comprehensive communication program involving hazard assessment,
labeling, material safety data sheets, and employee training through the
use of colors, numbers, letters, and symbols used to identify the
chemicals involved in the sudden spill or leak. |
|
Hazardous Materials (Haz-Mat) |
Any
substance or compound that has the ability to produce health effect in a
worker or a safely problem. A substance or material in a quantity or
form that may pose an unreasonable risk to health and safety, or
property, when transported in commerce. Hazardous Materials By federal
guidelines, all firefighters are required to be trained in hazardous
materials. There are three levels of training. Each level is more
technical than the previous level. The first level is Awareness. This is
the basis for all levels for identification and recognition of a
hazardous material or indicators of the presences of a hazardous
material. The next level is Operations. This level is where the hands on
training will give the firefighter basic knowledge in certain mitigation
techniques. The third level is Technician. This level, firefighters use
all the resources available to control the spill or leak from becoming
worse and determine certain factors that possibly could react with the
situation at hand. The training in the technician level is in depth.
Personnel have many other training certifications as well as having
their health conditions monitored before, during and after any
incident. |
|
Hazardous materials foam |
A special vapor suppressing mix which can be applied to liquids or
solids to prevent off-gassing . |
|
Hazardous Materials Response
Team (HMRT) |
An organized group of trained response personnel operating under an
emergency response plan and appropriate standard operating procedures
who handle and control actual or potential leaks or spills of hazardous
substances requiring possible close approach to the material. The team
members respond to releases or potential releases of hazardous materials
for the purpose of control or stabilization of the incident. An HMRT may
be a separate component of a fire brigade or a fire department or other
appropriately trained and equipped units from public or private
agencies. |
|
Hazardous materials
specialist |
Individuals
who respond and provide support to Hazardous Materials Technicians.
While their duties parallel those of the Technician, they require a more
detailed or specific knowledge of the various substances they may be
called upon to contain. Would also act as a liaison with federal, state,
local and other governmental authorities in regard to site activities. |
|
Hazardous materials technicians |
Individuals
who respond to releases or potential releases of hazardous materials for
the purposes of stopping the leak. They generally assume a more
aggressive role in that they are able to approach the point of a release
in order to plug, patch, or otherwise stop the release of a hazardous
substance. |
|
HAZWOPER (Hazardous Waste Operations and Emergency Response) |
The OSHA
regulation regarding the protection of worker health and safety in
situations exposing them to hazardous materials. This includes cleanup
operations; remediation after cleanup; hazardous waste disposal;
treatment or storage; or response to a hazardous material emergency. The
regulation also includes a section on training, documentation and
personal protective equipment and clothing. |
|
Head |
The front
and rear closure of a tank shell; water pressure due to elevation. For
every 1-foot increase in elevation, 0.434 psi is gained (for every 1
meter increase in elevation, 10 kPa is gained). Also called Head
Pressure. |
|
Head
lap |
The shortest
distance in inches from the lower edges of an overlapping shingle to the
upper edge of the unit in the second course below. |
|
Head pressure |
Pressure measured in feet (meters) or psi (kPa) resulting from the
elevation of water. Head pressure amount to 0.434 psi per foot (10 kPa
per meter) or 2.304 feet per psi (0.10 meter per kPa) |
|
Header
|
In framing,
the continuous joist placed across the ends of floor joists, the double
joists at each end of floor or ceiling openings attached to the
trimmers, and the structural member above window or door openings. In
masonry, exposed ends of masonry units laid horizontally. A beam placed
perpendicular to joists and to which joists are nailed in framing for a
chimney, stairway, or other opening. A wood lintel. The horizontal
structural member over an opening (for example over a door or window). |
|
Heading Fire |
Fire that
is moving with the wind (See backing and flanking fire). |
|
Health hazard |
A chemical
for which there is statistically significant evidence that acute or
chronic health effects may occur in an exposed human population. The
term "health hazard" includes chemicals which are carcinogens, toxic or
highly toxic agents, reproductive toxins, irritants, corrosives,
sensitizers, hepatotoxins, nephrotoxins, neurotoxins, agents which act
on the hematopoietic system and agents which damage the lungs, skin,
eyes, or mucous membranes. |
|
Hearth |
That part of
the floor directly in front of the fireplace, and the floor inside the
fireplace on which the fire is built. It is made of fire-resistant
masonry. |
|
Heat |
A form of
energy characterized by vibration of molecules and capable of initiating
and supporting chemical changes and changes of state. Heat is a form of
energy measured in degrees of temperature to signify its intensity. The
quality or condition of being hot; high temperature. The sensation or
perception of hotness or warmth as by the effect produced with contact
or nearness to fire. |
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Heat cramp |
A muscle
cramp accompanied by pain and nausea, caused by loss of salt and water
through excessive perspiration. |
|
Heat exhaustion |
A condition
caused by excessive exposure to heat and characterized by a cold, clammy
skin and general symptoms of shock; heat prostration. |
|
Heat of Ignition |
The heat
energy that brings about ignition. Heat energy comes in various forms
and usually from a specific object or source. Therefore, the heat of
ignition is divided into two parts. equipment involved in ignition and
form of heat of ignition. |
|
Heat pump |
A mechanical
refrigerating system used for cooling in the summer and which, when the
evaporator and condenser effects are reversed, absorbs heat from the air
or water in winter, thereby supplying heat. |
|
Heat rash |
An eruption
on the body typically with little or no temperature elevation: prickly,
heat. Inflammation of the sweat glands, which have become plugged due to
the skin swelling, thereby impairing sweating and diminishing a worker's
ability to tolerate heat. |
|
Heat Release Rate. (HRR) |
The
rate at which heat energy is generated by burning. The heat release rate
of a fuel is related to its chemistry, physical form, and availability
of oxidant and is ordinarily expressed as Btu/sec or kilowatts (kw). |
|
Heat stress |
The
physiologic effect on the body that can result from exposure to
excessive heat. Excessive heat stress may lead to heat stroke, beat
exhaustion, heat cramps, or prickly heat depending on the temperature,
humidity, conditioning of the person exposed, ventilation, rest breaks,
temperature of the rest area, availability of tempered water, and other
factors. The strain placed on the body as it attempts to cope with
excess internal heat. A physical, chemical, or emotional factor (as
trauma or fear) to which an individual fails to make a satisfactory
adaptation. It causes physiologic tensions that may be a contributory
cause of disease. The state or condition of strain and especially of
intense constraining forces due to excessive heat exposure. |
|
Heat stroke |
Severe
exhaustion and collapse or sudden illness caused by overexposure to
heat, as from the infrared rays of the sun. The body's mechanism to self
cool through evaporation of sweat shuts down. The result is an increase
in core body temperature. This is a medical emergency as coma and death
is near. |
|
Heat transfer |
The movement and dispersion of heat. Heat is transferred by convection,
conduction, and radiation. See law of heat flow. |
|
Heating load |
The amount
of heating required to keep a building at a specified temperature during
the winter, usually 65° F, regardless of outside temperature. |
|
Heating Ventilating and Air
Conditioning system [HVAC system] |
The system
that is in place to provide ventilation, heating, cooling,
dehumidification, humidification, control of odors, and cleaning of the
air for maintaining comfort, safety, and health of the occupants of a
building, workspace, etc. |
|
Heavy duty appliances |
Master stream equipment with large tips generally fed by two or
more separate hose lines. |
|
Heavy rescue vehicle |
Large rescue
vehicle that may be constructed on a custom or commercial chassis.
Additional equipment carried by the heavy rescue unit includes A-frames
or gin poles, cascade systems, larger power plants, trench and storing
equipment, small pumps and foam equipment, large winches, hydraulic
booms, large quantities of rope and rigging equipment, air compressors,
and ladders. |
|
Heavy stream |
A large stream too heavy for conventional manual operation; a stream of
400 gpm (1,514 L/min) to 1,200 gpm (4542 L/min) or more. See Master
Stream. |
|
Heel |
The base of a ladder, the steadying of a ladder while it is being raised
or, to secure a raised ladder. Also known as the butt. |
|
Heel cut |
A
notch cut in the end of a rafter to permit it to fit flat on a wall and
on the top, doubled, exterior wall plate. |
|
Heel plate |
1) A metal reinforcement at the heel or butt end of a ladder, generally
shaped to give the ladder more stability.2) A plate at the ends of
truss. |
|
Heli-base |
The main location for parking, fueling, maintenance, and loading of
helicopters operating in support of an incident. It is usually located
at or near the incident Base. |
|
Heli-spot |
Any designated location where a helicopter can safely take off and land.
Some heli-spots may be used for loading of supplies, equipment, or
personnel. |
|
Helmet |
The regulation protective headwear for firefighters that provides
protection from falling objects, side blows, the fire environment
elements, and eye injuries. |
|
Helmet Face Shield |
A clear protective plastic shield attached to a helmet to protect the
face. |
|
Helmet identification shield |
The insignia or plaque fastened to the front of the
firefighter's helmet that generally displays the name of the city,
initials, unit, rank, and number. |
|
Hemoglobin |
The
red respiratory protein of red blood cells that transports oxygen as
oxyhemoglobin from the lungs to the tissues, where the oxygen is readily
released and the oxyhemoglobin becomes hemoglobin. |
|
Hierarchy of Command |
See Chain of Command |
|
Higbee cut |
A
special cut at the beginning of the thread to provide positive
identification of the first thread and to eliminate cross threading. |
|
Higbee indicators |
Notches or grooves cut into coupling lugs to identify by touch or sight
the exact location of the Higbee cut. |
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High expansion foam |
Detergent-base foam that expands in ratio of 1,000 to 1. A special
generator that normally uses some type of fan or blower projecting the
foam solution against a screen makes the finished foam. |
|
High Explosive |
A
material that is capable of sustaining a reaction front that moves
through the unreached material at a speed equal to or greater than that
of sound in the medium (typically 3300 ft/sec (1000 m/sec); a material
capable of sustaining a detonation. (See also Detonation.) |
|
High Order Explosion |
A
rapid pressure rise or high force explosion characterized by a
shattering effect upon the confining structure or container and long
missile distances. |
|
High pressure fog |
A fog stream operated at high pressures and discharged through
small-diameter hose. |
|
High pressure hose |
Hose leading
from the air cylinder to the regulator; may be at cylinder pressure or
reduced to some lower pressure. |
|
High pressure nozzle |
Fire stream
nozzle that is designed to be operated in excess of the 100 psi (700
kPa) to which ordinary fog nozzles are designed. |
|
High rise building |
Any building that requires fire fighting on levels above the reach of
the department's equipment. |
|
High rise pack |
A special kit for high-rise operations containing hose, adapters,
nozzle, and spanner wrenches. |
|
High temperature protective clothing |
Protective clothing designed to protect the wearer against short-term
high-temperature exposures. Includes both proximity suits and fire entry
suits. This type of clothing is usually of limited use in dealing with
chemical exposures. |
|
High value district |
A section of a city in which valuable property is located and in which
additional companies and apparatus are needed to combat a fire. |
|
Hip |
A roof with
four sloping sides. The external angle formed by the meeting of two
sloping sides of a roof. |
|
Hip roof |
A roof that
rises by inclined planes from all four sides of a building. |
|
Hitch |
A loop of
rope that secures the rope but is not part of a standard rope knot. A
connecting device at the rear of a vehicle used to pull a trailer with
provision for easy coupling |
|
Home run (electrical) |
The
electrical cable that carries power from the main circuit breaker panel
to the first electrical box, plug, or switch in the circuit. |
|
Honey combs |
The
appearance concrete makes when rocks in the concrete are visible and
where there are void areas in the foundation wall, especially around
concrete foundation windows. |
|
Hood |
A NOMEX®
hood is a common piece of firefighting equipment. It is placed on the
head on top of a firefighters face mask which supplies air to him inside
a smoke filled environment. The hood protects the portions of the head
not covered by the helmet and face mask from the intense heat of the
fire. |
|
Hook |
Curved metal devices installed on the tip end of roof ladders to secure
the ladder to the highest point on the roof of a building. Plaster hooks
are devices resembling a pike pole for pulling down plaster and
ceilings. |
|
Hook and Ladder |
A term for a type of ladder truck. Traditionally, this apparatus is in
two parts. The tractor pulls a long trailer with a mechanical extension
ladder over 100 feet and a compliment of ground ladders. The trailer is
known as tiller, which is guided by a person that sits on the end of the
trailer and steers the trailer around corners. This person is known as
the tillerman. The 'hook' of hook and ladder comes from early days when
large hooks were used to assist in fighting fires. Pike poles with hooks
on the end of the pole have replaced earlier hooks. |
|
Hooking up |
Connecting a fire department pumper to a hydrant or connecting a
discharge hose to the pumper. |
|
Horseshoe load |
Hose loaded
around the periphery of the hose bed compartment in the form of a
horseshoe. |
|
Hose |
Hose is used to deliver water onto a fire and to provide
water from hydrants to firefighting apparatus. The types of
hose used include handline, booster lines and large diameter hose. |
|
Hose bed |
Main
hose-carrying area of a pumper or other piece of apparatus designed for
carrying hose. The part of the apparatus where the majority of the hoses
are stored. Many different types and sizes can be stored in this area
and can sometimes be seen from behind the apparatus. Some of the hoses
are pre-connected and even the long heavy lengths can easily be pulled
off and quickly put into service. Also called Hose Body. |
|
Hose belt |
A leather belt or nylon strap used for securing and handling charged
hose lines, tools, or tying off a ladder. |
|
Hose body |
The main hose compartment of a pumper or other piece of apparatus
designed for carrying hose. Also called hose bed. |
|
Hose bridge |
A
device placed astride hose so traffic can pass over without damaging the
hose. |
|
Hose cabinet (rack) |
A recessed cabinet in a wall that contains a wall hydrant and connected
hose. |
|
Hose clamp |
A mechanical or hydraulic device to compress fire hose to stop the flow
of water. |
|
Hose control device |
Device used
to hold a charged hose line in a stationary position for an extended
period of time. |
|
Hose couplings |
Metal
fasteners used to connect fire hose together. |
|
Hose dryer |
An enclosed cabinet containing racks on which fire hose can be dried. |
|
Hose hoist |
A metal device having a roller that can be placed over a windowsill or
roofs edge to protect a hose and make it easier to hoist. |
|
Hose jacket |
The fiber jacket (s) around the rubber inner liner of a hose. A device
placed around a broken hose to contain the leak or around damaged or
dissimilar couplings to join them. |
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Hose rack |
Racks
for storing and drying fire hose. |
|
Hose reel |
Cylinders around which fire hose can be manually or mechanically rolled
to keep it neat and orderly. |
|
Hose strap |
A strap or chain with a handle suitable for placing over a ladder rung
used to carry and secure a hose line |
|
Hose tower |
Part of a fire station or building designed so fire hose can be hung
vertically to drain and dry. |
|
Hot wire |
The wire
that carries electrical energy to a receptacle or other device—in
contrast to a neutral, which carries electricity away again. Normally
the black wire. Also see ground. |
|
Hot zone |
An area
immediately surrounding a hazardous materials incident that extends far
enough to prevent adverse effects from hazardous materials releases to
personnel outside the zone. This area is also referred to as the
"exclusion zone," the "red zone" and the "restricted zone" in other
documents. |
|
Hotel raise |
A method of raising a fire department extension ladder in line with
several windows so individuals can simultaneously escape from more than
one floor. (Also called factory raise.) |
|
House lights |
The lights throughout the fire station that are controlled from the
alarm or watch desk which makes it possible to illuminate the entire
station in case of an emergency. |
|
House line |
A permanently fixed, private standpipe hose line. A hose line in a
building for firefighting in that building. Interior standpipe hose
often seen in hallways or stairwells of hotels. |
|
House watch |
The duty of maintaining the fire station alarm center for a prescribed
period of time. |
|
Household Hazardous Waste (HHW) |
Hazardous materials, such as paints, pesticides, motor oil and
batteries, that require careful storage and proper disposal. |
|
HSAC |
Homeland Security Advisory Council |
|
HSOC |
Homeland Security Operations Center |
|
HSPB |
Homeland Security Protection Board |
|
HSPD-5 |
Homeland Security Presidential Directive - 5 |
|
HSPD-8 |
Homeland Security Presidential Directive - 8 |
|
Humidity |
The water
vapor in air. Absolute humidity refers to the amount of water vapor in a
given volume of air; relative humidity is the ratio of the density of
water vapor to the saturation density at a particular temperature and
barometric pressure. |
|
Hurricane clip |
Metal straps
that are nailed and secure the roof rafters and trusses to the top
horizontal wall plate. Sometimes called a Teco clip. |
|
Hydrant |
An upright metal casting connected to a water supply system and equipped
with one or more valved outlets to which a pumper or hose line can be
connected. Also this has been given the name 'plug' or 'catch a plug'.
This term comes from early days of firefighting when water mains were
nothing more than hollowed out trees, buried in the ground. When a fire
company needed water, they would dig down to the log, and open a hole in
the tree for a water supply. After the fire, the hole had to be
'plugged' in order to stop the flow of water. |
|
Hydrant adapter |
An adapter, fitting, or coupling to connect hose or pumper intake hose
to a fire hydrant. |
|
Hydrant pressure |
Amount of
pressure being supplied by a hydrant without assistance. |
|
Hydrant wrench |
A specially-designed tool used to open or close a hydrant and to remove
hydrant caps. |
|
Hydration |
The
combining of a substance with water. Also, in medical terms the process
of maintaining a stasis of water and electrolytes at the cellular level
through replenishment of fluids orally or intravenously. This stasis is
important to firefighters to prevent or reverse the effect on the body
of heat related emergencies such as heat exhaustion. |
|
Hydraulics |
The study of
the use and movement of fluids at rest and in motion. Operated, moved,
or effected by means of water; of or relating to water or other liquid
in motion; operated by the resistance offered or the pressure
transmitted when a quantity of liquid is forced through a comparatively
small orifice or through a tube; branch of fluid mechanics dealing with
the mechanical properties of liquids and the application of these
properties in engineering. |
|
Hydrocarbons |
Combinations of hydrogen and carbon that form many compounds. Petroleum
products and natural gas are mixtures of several hydrocarbons. |
|
Hydrolysis |
The reaction
of any chemical substance with water by which decomposition of the
substance occurs and one or more new substances are produced. |
|
Hypergolic |
A chemical
reaction between a fuel and an oxidizer that causes immediate ignition
on contact without the presence of air. An example is the contact of red
fuming nitric acid and UDMH (unsymmetrical dimethyl hydrazine). Two
chemical substances that spontaneously ignite upon mixing. A term used
to describe two substances that spontaneously ignite upon mixing. |
|
Hypergolic mixtures |
Certain fuels and oxidizers that will ignite on contact with each other
without an ignition source. |
|
Hyperventilation |
Rapid breathing that over oxygenates the blood and eliminates too much
carbon dioxide. Carbon monoxide is the primary means of triggering the
respiratory center of the central nervous system. |
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