Potter Releasing Systems - Manual (Page 7)

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Evacuation Signal - Distinctive signal intended to be recognized by the occupants as requiring evacuation of
the building.
Exit Plan - Plan for the emergency evacuation of the premises.
Fire Alarm Control Unit [Panel] - A system component that receives inputs from automatic and manual fire
alarm devices and may supply power to detection devices and transponders or off-premises transmitters. The
control unit may also provide transfer of power to the notification appliances and transfer condition of relays or
devices connected to the control unit. The fire alarm control unit can be a local unit or a master control unit.
Fire Rating - The classification indicating in time [hours] the ability of a structure or component to withstand
fire conditions.
Fire Safety Functions - Building and fire control functions that are intended to increase the level of life safety
for occupants or to control the spread of harmful effects of fire.
Flame Detector - A device that detects the infrared, ultraviolet, or visible radiation caused by fire.
Four Wire Smoke Detector - A smoke detector which initiates an alarm condition on two separate wires
[initiating circuit] separate from the two power leads.
Heat Detector - A device that detects abnormally high temperature or rate of temperature rise.
Initiating Device - A system component that originates transmission of a change of state condition, such as a
smoke detector, water flow switch, etc.
Initiating Device Circuit - A circuit to which automatic or manual initiating devices are connected.
Ionization Smoke Detector - A smoke detector that has a small amount of radioactive material which ionizes
the air in the sensing chamber, thus rendering it conductive and permitting a current to flow between two
charged electrodes. This gives the sensing chamber an effective electrical conductance. When smoke particles
enter the sensing chamber they decrease the conductance of the air by attaching themselves to the ions, causing
a reduction in mobility. When conductance is reduced to less than a predetermined level, the detector responds.
Level Ceilings - Those ceilings that are actually level or have a slope of less than 1½ in. per foot.
Light Scattering - The action of light being reflected and/or refracted off particles of combustion for detection
by a photoelectric smoke detector.
Line Type Detector - A device in which detection is continuous along a path. Examples include projected beam
smoke detectors and heat sensitive cable.
Listed - Equipment or materials included in a list published by an organization acceptable to the “authority
having jurisdiction” and concerned with product evaluation, that maintains periodic inspection of production of
listed equipment or materials and whose listing states either that the equipment or material meets appropriate
standards or has been tested and found suitable for use in a specific manner. Note: The means for identifying
listed equipment may vary for each organization concerned with product evaluation, some of which do not
recognize as listed unless it is also labeled. The “authority having jurisdiction” should utilize the system
employed by the listing organization to identify a listed product.
Local Fire Alarm System - A local system sounding an alarm at the protected premises as the result of the
operation of automatic or manual initiating devices.
Manual Station [pull station] - A manually operated device used to initiate an alarm signal.
National Electrical Manufacturers Association [NEMA] - is a U.S. trade organization representing
manufacturers of products used in the generation, transmission, distribution, control, and end-use of electricity. Many
of NEMA’s standards have been approved as American National Standards or adopted by the federal government.