Planning
Fire detection
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Building Technologies
A6V10305793_m_en_--
Fire Safety
2016-02-15
Room geometry
High ceilings, complex room shapes or well-ventilated rooms have a complex room
geometry. This aggravates early fire detection, as it is difficult for the fire
phenomenon to reach the fire detector. An office room with normal ceiling height
has a simple room geometry.
Deceptive phenomena
Deceptive phenomena can deceive a fire detector and bring about a false alarm.
The deceptive phenomena differ depending on the fire detector. Deceptive
phenomena include
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Steam
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Cigarette smoke
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Dust
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Dry ice in discotheques
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Exhaust fumes
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Aerosols produced when welding
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Sources of heat such as radiant heaters or hot engines
In a small hotel room with a rather low ceiling where vapor from the bathroom may
penetrate the room, or in operating facilities where a lot of dust is generated, many
deceptive phenomena must be taken into consideration. In a clean room where
electronic modules are fabricated the risk of deceptive phenomena is rather low.
Risk of fire
In production facilities where highly combustible materials such as flammable
liquids, cotton, paper etc. are processed and where electrical machines are
operated, the fire risk is very high. Minor overheating or sparks may cause a fire. In
a storehouse where steel is stored and where no electrical installation is provided
with the exception of lighting, the fire risk is very low.
Critical fire size
When a waste paper basket in a metal-processing facility catches fire, the
consequential damage is usually rather low. Here we are talking about a critical,
medium fire size that can still be tolerated. The situation is completely different in
pharmaceutical production facilities where even the lowest smoke concentration
may impair the process and where combustible materials are processed. Even the
smallest fire must be detected immediately. In this case, we are talking about a
small admissible critical fire size.
