Fire detection systems

According to fire regulations, every room in a historic building has
to be equipped with fire detection unit. The most standard approach
is to install an ionization detector, which is a rather big, white
plastic "tablet", which cannot be painted. If on white ceilings they
look more or less tolerable; on painted ceilings they do not.

Has anybody heard about ionization detectors which can be painted?
Or are there any detectors (like heat cables), which can be sunk
into the plaster?

A good comparison of systems and Norwegian experience can be found
here:

    <URL:http://www.heritagefire.net/
        heritage_fire_wg_papers/wg2/
        Detection_Contents_and_Executive_summary_only.pdf>

    **** Moderator's comments: The above URL has been wrapped for
    email. There should be no newline.

Arturs Lapins,
Architect


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                  Conservation DistList Instance 23:9
               Distributed: Thursday, September 24, 2009
                        Message Id: cdl-23-9-025
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