Errol:
 
I suggest that you consult CCI Note #10/3 "Storage and Display
Guidelines for Paintings".  If you do not have a copy of the CCI Notes
they are available from the Canadian Conservation Institute, 1030
Innes Road, Ottawa, Ontario, K1A 0C8 (613) 998-3721.  Their
publications are quite good and are free.  Good luck.
 
Susan L. Maltby, Conservator
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