Circulation of brittle books

Does anyone have guidelines you can share about the circulation of
brittle books?  Of course books that are not intact ought not circulate!
What I'm after, however, are real-world practices and procedures applied
when brittle volumes remain in general, circulating collections.
Whether shrink wrapped or boxed or setting unprotected on the shelf, how
do you control the handling of fragile (at risk) materials,
assuming--for whatever reason--that they cannot be immediately
reformatted.  What do you tell the potential user at the Circulation
desk?  Or do you insert a message in the book itself?  How do you
protect such items during photocopying?  Please respond to me directly
and I will summarize for the list.

(My previous query regarding professional moving companies garnered very
little information (Cons DistList Instance: 7:81).  My thanks to those
who did provide leads.  Nothing substantive enough to report has
resulted, however.)

Regina Sinclair
Head, Preservation Department
Johns Hopkins University

                                  ***
                   Conservation DistList Instance 8:6
                   Distributed: Sunday, July 10, 1994
                        Message Id: cdl-8-6-006
                                  ***