Fog machines

Has anyone had any experience with fogging machines?  Or does any- one
know enough about them to tell me whether they are environmentally
harmful when used around library collections?  These contraptions are
used to create smoke in movies.  They supposedly involve the use of
mineral oil.

Thanks for your attention!    rs

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                  Conservation DistList Instance 5:31
                Distributed: Saturday, December 7, 1991
                        Message Id: cdl-5-31-004
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