User Manual

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Siemens Switzerland Ltd
Building Technologies Division
3.2. Fire detection in historical buildings
We are often confronted with a historical building that does not yet have an automatic fire detection system
installed. However, bearing in mind the life safety aspect and the underlying need to protect cultural heritage
against fire damage, installation of such an automatic fire detection system must be considered a high priority.
However, to allay the fears of the conservationist we need to adhere to the principles of minimal invasive
detection.
3.2.1. Rooms with ornate ceilings
Historical buildings and museums typically have high ornate ceilings, with molded cornices and wooden wall
paneling. The task is to install a fire detection infrastructure, which has minimum impact on the fabric and décor
of the building.
Figure 9 Room with ornate ceiling
ASD (Aspirating Smoke
Detection)
The high fire risk in historical buildings and museums means that the earliest
possible detection of incipient fire is even more important. ASD (Aspirating
Smoke Detection) systems have proved to be ideal in such applications, as they
not only provide extremely sensitive smoke detection, but they can also be made
practically invisible. The associated narrow pipes can be hidden in ceiling voids or
behind the stucco cornices that can frequently be found in ornate ceilings.
ASD systems are also an ideal solution for supervising the glass showcases that
are often used in museums to display sensitive artifacts. They can identify any
incipient fire that may have been caused by an electrical fault or overheating of
the associated showcase light fittings.
Wireless detector network Where they can be positioned without interfering with the room aesthetics,
modern, sensitive point detectors may used. By utilizing a wireless network of
such detectors it is now possible to fulfill the conservationists’ requirement for
minimal invasive detection. Earlier generations of such devices exhibited certain
disadvantages, such as signal loss and frequent battery replacement. However,
recent technological developments have overcome these difficulties.
Communication redundancy is now provided by mesh-network constellations,
which means that at least two redundant paths are available to transmit the
signal back to the fire control panel. Reliability has also been further increased by
each detector having two frequency bands with multiple channels. Such
networks can now cover a considerable area. Battery lifetime, which was a
concern in earlier models, has also been considerably extended and is no longer
a problem.