High-pressure water washing

A client of mine has asked if I have had, or have heard of anyone
who has had experience with damage caused to historic glass in
windows when the building has been washed with high-pressure water.
The building was recently washed (prior to my involvement with the
organization) and the staff are concerned that the glass has been
pitted.  They now realize that this is not a good cleaning technique
for an historic structure!  The building was constructed in the
early 19th century, but we are unsure what percentage of the glass
is original.  My examination last week indicated that quite a number
of the panes are "wavy".  No UV film has been installed on the
glass.

I said that I would put this query out to see if any else out there
has noted this type of damage. Thanks,

Wendy Claire Jessup
Wendy Jessup and Associates, Inc.
210 Little Falls Street, Suite 203
Falls Church, Virginia  22046
703-532-0788
Fax: 703-532-1661

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                  Conservation DistList Instance 10:13
                  Distributed: Thursday, July 25, 1996
                       Message Id: cdl-10-13-009
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