Positive pressure ventilation and filtering systems

I am looking for information about positive pressure ventilation and
filtering systems in use in museums. In particular, I would need to
know how they work, how efficient and costly they are. Any
information is welcome,

Serena Albanese
Book and Paper Conservation Studio
Dundee University Library
UK


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                  Conservation DistList Instance 21:29
                 Distributed: Sunday, November 4, 2007
                       Message Id: cdl-21-29-019
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