User Manual

15
3.2 Fire detection in education facilities
As discussed earlier many different types of room may
be found in colleges and universities. These rooms not
only differ in size and function but also in the range of
deceptive phenomena that can be found there. Selecting
the correct type of fire detector, with the appropriate
settings for each application requires detailed knowledge
of the products and their behavior under the various
environmental conditions. Providing optimal solutions will
often require the use of specialized detection techniques.
The following paragraphs describe typical examples of
such techniques.
The use of multi-criteria ASA detectors in conjunction
with the appropriate know-how
In some cases the deceptive aerosols may be sufficiently
intense to trigger an alarm even though there is no
immediate danger of fire. In fact, student accommodation
provides us with two such examples. In the common
kitchen area excessive steam from boiling water or
cooking aerosols from an unattended saucepan may
trigger an alarm from a basic smoke detector. Combining
aerosol detection with heat detection, however, ensures
that an alarm will only be triggered when there is a
genuine danger. Small student bedrooms with en-suite
bathrooms are a second example, where excessive steam
from the shower may trigger unnecessary alarms if the
bathroom door is suddenly opened before the steam has
had time to dissipate.
The use of ASD (Aspirating Smoke Detection)
in high-tech applications
Technical universities in particular have a number of
applications which require the earliest possible detection
of an incipient fire. These include cleanrooms, where
even a minor fire would have devastating consequences,
and electrical plant rooms where early fire detection can
be instrumental in preventing extremely costly fire
damage. ASD (Aspirating Smoke Detection) systems have
proved to be ideal in such applications, as they provide
extremely sensitive smoke detection even in rooms with
high air circulation rates.
The use of wireless detectors in the renovation of
post-war buildings
During building renovation work or due to insufficient
classroom space, education authorities often have to
resort to temporary classroom buildings. In such cases
(and also in educational premises that are classified as
historical buildings, where cable installation may be an
issue) wireless detectors may offer an effective solution.
This is particularly relevant in buildings from the second
half of the 20th century, when asbestos was a frequently
used building material. In many countries the presence of
asbestos is still tolerated (mainly due to the extremely
high cost of its removal). During building work, however,
it can become extremely dangerous when asbestos dust is
generated by sawing or drilling. As there would be a high
probability of this occurring if cables were installed in
such buildings, the use of wireless detectors is an elegant
way of avoiding such a risk.
The use of linear smoke detectors
In colleges and universities there are numerous rooms
with high ceilings. Any room where the ceiling height
is 6 m or more is the perfect application for linear smoke
detectors. Such devices can cover distances of up to
100 m. They generally contain an infrared transmitter
and detector in the same housing, with only a reflector
required on the opposite wall, which greatly simplifies
the installation process.
In any space where there is a potential for smoke
stratification, detectors installed at ceiling level only,
might not activate until after a serious delay.
To provide the most effective protection, a total
surveillance concept is generally recommended to ensure
that the entire building is monitored. This includes not
only all rooms, corridors, staircases and anterooms, but
also all air conditioning and cable ducts, supply shafts,
false ceilings, raised floors, and similar structures which
could permit smoke and fire to spread.
Most universities will contain a number of the following
critical areas:
 Student accommodation
 High-tech laboratories (e.g. cleanrooms)
 Event venues
 Libraries
 Archives
 Lecture theaters
 Kitchens
 IT and electrical plant rooms