Herbarium materials

Does anyone have experience how to create an air filtering (HEPA)
system for cleaning of non-standard size herbarium sheets containing
hazardous particles?

I suppose e.g. PEL Cleaning Machine with a Herbarium Top is designed
for the standard size vascular sheets, but it's not suitable for
tiny lichen specimens glued on very small labels. Some of the
specimens are very light and fragile, so they can easily get lost or
damaged during the treatments. Because of the small size you have to
see them very close while you're working.

You can protect yourself with a respirator and gloves, but how to
keep the working area free of hazardous dust without damage or loss
of valuable specimens? Using the fume cupboard and putting your head
(using respirator) inside to see well what you are doing doesn't
sound very ergonomical if there are numerous labels to clean. Is it
even effective and also safe for the specimen?

This collection has scientific value (plenty of type specimens). The
specimens are glued on original labels. The labels  are  soiled  by
pollutions including lead and mercury from the board they're
mounted.

I would also like to know if anyone has carried out specific
research about herbarium mounting materials (papers, covers,
envelopes, seal bags etc.) and studied what kind of chemical or
physical changes can be caused for botanical specimens by wrong kind
of mounting/storage materials? Could some materials for example
change the chemical composition of some specimens and result in
erroneous information for the botanical research?

Eeva-Maria Tikka
Paper conservator
Botanical Museum
P.O. Box 47
FIN-00014 University of Helsinki
Finland


                                  ***
                  Conservation DistList Instance 15:23
                Distributed: Tuesday, September 11, 2001
                       Message Id: cdl-15-23-016
                                  ***