Storing formaldehyde solutions

Michelle Berry <mberry [at] museum__vic__gov__au> writes

>I am seeking information regarding the storage of large volumes of
>4% formaldehyde solution. ...
>...
> ... We are
>currently identifying risks and one of them is the potential affect
>of formaldehyde vapour on the historical and technological materials
>housed in the same space. The tank will be sealed however we expect
>that there will be some evaporation into the space. ...

Assuming that the tank will be secure and that temperature
fluctuation will not be in excess of 10 deg. C, then you will need
to ensure that the seal is not compromised.  You will need to have a
see-through and resealable inspection panel however (see below).
Formaldehyde gas can be detected using Schiff/Feulgen papers or,
using more sophisticated detectors which can monitor formalin gas
down to below olfactory detection.

Ensure that the specimen is inspected at least annually--after
summertime is best, since lipid from the shark's liver (especially)
may contaminate the fluid and if not removed by skimming, will
oxidise into fatty acids and lead to tissue breakdown. Temperature
fluctuation will cause polymerisation of the fluid into para- and
meta-formaldehydes--white solids.  These are not too serious
provided that the specimen is still, at least visible. Formaldehyde
gas will have a deteriorative effect on many media but only if
levels are above c. 100ppm.  TLV is 0.3ppm.

Simon Moore, MIScT, FLS, ACR,
Senior Conservator of Natural Sciences.
Hampshire County Council
Recreation and Heritage Department,
Museums and Archives Service,
Chilcomb House, Chilcomb Lane,
Winchester SO23 8RD UK.
+44 1962 826737


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                  Conservation DistList Instance 21:25
                 Distributed: Saturday, October 6, 2007
                       Message Id: cdl-21-25-004
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