Boric acid

Elizabeth Branigan <elizabeth.branigan [at] durham__ac__uk> writes

>A local historic library has a mould problem under the floor--in the
>void--with mould on the joists. It is recognised that this needs to
>be tackled at source with the introduction of air circulation and
>other methods but in the meantime the architect has suggested using
>ProBor 20 (Boric acid) as a treatment for the timbers to kill the
>mould spores and prevent regrowth. ...

Liz Branigan asked in Instance 25:26 whether ProBor 20 would be safe
to use to treat the floor timbers in a library.  I don't think there
would be a problem with off-gassing: according to the manufacturer's
data, ProBor 20 contains disodium octaborate and
dimethyldidecylammonium chloride in a viscous carrier containing
glycerol and butanediol.  The butanediol is the only volatile
component, and although it would take a while to disperse it
wouldn't be harmful to the books or to the staff. I think treating
the timbers with alcohol would be much less effective and would give
a much greater degree of off-gassing.

Dr Barry Knight
Head of Conservation Research
The British Library
96 Euston Road
London NW1 2DB
+44 20 7412 7229
Fax: +44 20 7412 7658


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                  Conservation DistList Instance 26:27
                Distributed: Tuesday, November 27, 2012
                       Message Id: cdl-26-27-010
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