F08 Installation & Programming Manual
Document No: LT0082
Application Considerations
5.3
PREVENTION OF NON “FIRE” ALARMS
All fire detection systems rely on their ability to identify atmospheric or environmental
changes brought about by the presence of fire. They employ various types of sensors to
monitor specific conditions. These devices signal a warning when an abnormal condition
exits, indicating either the actual presence of a fire or the immediate likehood of one.
Detectors monitor a number of physical phenomenon, which include smoke, heat, flame,
pressure, or the presence of combustion products such as gases to detect a fire. However,
some or all of these conditions may appear in different ways when there is no fire present
and trigger an un-wanted alarm. For example:
(a)
HEAT SOURCES; The sudden increase in local temperature when a furnace door is
opened can trigger heat sensors.
(b)
DRAUGHTS; Wind-induced surges of steam or dust can cause smoke detectors to
generate an alarm signal.
(c)
ENVIRONMENT CHANGES; Changes to wall partions, Air-Duct position or air
velocity can cause detectors to be forced into continuous alarm.
(d)
UNUSUAL ACTIVITIES; Portable welding units can activate flame detectors, while
spray-painting 'drift' can trigger smoke detectors.
(e)
RADIO INTERFERENCE; In extreme situations some electronic detectors may
suffer from electromagnetic interference from radio transmitters or other electrical
noise generating devices.
It is therefore highly recommended that the service company be aware of all site conditions
and be notified of any changes to the occupancy or physical aspects of the building or area
being protected.
Page 5-10
24 March 2006
Issue 3.04
Summary of Contents for F08
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