Photographic collections and particulates

I wonder whether you are able to help me by your own experience or
research, or by pointing me in a direction where I may find advice.
I am the collection manager for English Heritage's National
Monuments Record, a collection of about 10 million photographs of
England's Archaeological and Architectural heritage. Our purpose
built Archive which was completed about 8 years ago has stable
environmental conditions maintained by computer controlled Building
Management Systems. The environment of our negative store is
currently set for 8 deg. C and 32% RH giving us a preservation
factor of about x10. The air handling units which feed the vaults
have particle, dust and carbon filters. When needed the photographs,
glass plate negatives, film negatives and prints are removed from
the relevant vaults, pass through acclimatisation procedures, if
necessary, and are taken to the work and viewing areas.

We have just learnt about a planning application which has been
submitted to site a aggregate distribution centre on the land
adjacent to our Archive's main air intakes, some heaps of aggregate,
stone, or sand etc could be as close as 25-30 meters. Have you any
experience of how dust and airborne contaminants from these piles of
stones might effect us? Obviously our filters will need careful
monitoring and probably far more frequent renewal, but how will the
dust which inevitably will creep through the system or enter our
work and public viewing areas, which are not air conditioned and
rely on open windows in the summer for ventilation, effect our
photographs. One reads in all the good literature on photographic
preservation about keeping photographs in stable environments, away
from light and dust but I have not seen any reasons given why away
from dust. Of course there are the obvious ones which I have thought
of already; 1. Dust on negatives make them difficult to print
properly without blemishes and spots. 2. If the dust is gritty then
the surface of the emulsion could get scratched. 3. Some enclosures
and film bases can become electrically charged attracting more dust
and making the situation worse. That's where I run out of ideas. If
we are to make a good case to stop this aggregate store or move it
further away from our archive I will need more than this. Can you
help ?

Tony Rumsey
Collections Manager
National Monuments Record
English Heritage


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                  Conservation DistList Instance 15:80
                   Distributed: Friday, May 24, 2002
                       Message Id: cdl-15-80-007
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