User Manual

Siemens Switzerland Ltd

Building Technologies Division

Linear smoke detector In historical buildings and museums there are many 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 permit smoke

and fire to spread.

Special attention should be given to critical areas where many people may be present, areas with numerous heat

sources, large fire loads or significant deception phenomena.

Many historical buildings and museums are visited by large numbers of people and in many cases refreshment

and catering facilities are provided. Such buildings may contain a number of the following critical areas:

· Exhibition rooms

· Archives

· Restaurants and cafés

· Kitchens

· Electrical plant rooms

3.2.2. Exhibition rooms

Figure 10 Exhibition rooms

Historical buildings and museums generally have a number of

large exhibition rooms with high ceilings. Although deceptive

phenomena do not generally occur in such rooms, the height

of the room (and the large volume of air) will cause the

concentration of any fire-related aerosol to be strongly

diluted. This demands high sensitivity smoke detection, which

can be best provided by an ASD (Aspirating Smoke Detection)

system.

In some cases, however, the installation of such a system in a

historical building may not be permissible, due to restrictions

made by the conservationist lobby. In such cases, an

aesthetically acceptable solution could be provided by a

combination of linear smoke detectors and a wireless network

of sensitive point type smoke detectors.

Exhibition rooms may also contain a number of glass display

cases. An ASD system can provide an excellent solution for

monitoring such showcases as it can detect an incipient fire

(e.g. caused by an electrical fault or overheated light fitting)

at the earliest possible stage.

More detailed information regarding fire detection in

exhibition rooms is given in the document “Fire detection in

exhibition rooms”.