Heating museum materials

I'm working for a museum of cultural history, which is in the
process of establishing a treatment facility against pests. The
museum can afford to get a room which can either freeze or heat the
objects. As a conservator I initially opposed the idea of heating
museum objects, but it seems to have a few, but very important,
benefits: If saves a lot of time, because you don't have to wrap
each object carefully and tight, and it kills both insects and
mold/fungus at the same time. Furthermore the museum is interested
in heating because this is the cheapest option.

A danish conservator has made a lot of experiments, and has a long
experience, of heating different material, both old and new objects.
He draws the conclusion that the risk of damages is minimal when you
heat an object to 50 degrees C (with a few exceptions, like tempera
paint). But heating the object to 50 degrees actually involves a
higher temperature in the air, as long as the object is still
heating up. This conservator has developed a special heating chamber
with humidity control and a big fan, which distributes
heat/moisture. There is a big screen which prevents direct heat on
the objects. Objects are placed on "bars" to make heating even. A
heat treatment would last for around one working day.

I trust the conservator's good experience, but still I can't help
feeling bad about heating the material. Is there anyone using or
experimenting with heat treatment, who can give me some comments on
their experience? If so, which material don't you heat (48 degrees C
is said to be the minimum for killing insects)?


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                  Conservation DistList Instance 15:58
                Distributed: Tuesday, February 19, 2002
                       Message Id: cdl-15-58-007
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