Fire retardant plastic sheeting

Whitney Baker <wbaker<-a t->ku< . >edu> writes

>...  The agent suggested replacing plastic
>visqueen with fire retardant tarps to lower the flammability of the
>sheeting.
>
>The manufacturer states that the tarp "consists of two sheets of
>high strength fire retardant film laminated together with a third
>layer of molten polyethylene".  I would welcome comments from the
>conservation community on having fire-retardant plastic in contact
>with collections on a semi-permanent basis.

No one can answer your question without knowing the identity of the
fire retardant chemicals--which they are unlikely to provide.

We know that the polybrominated diphenyl ethers that are commonly
used will migrate out.  And, there is a really nasty brominated DEHP
phthalate called FireMaster 550 that migrates.  Some inorganic fire
retardants are very stable, but we don't see them in plastic
sheeting as much as in fabrics.  Most plastics that are meant for
roof membranes and other outdoor uses usually contain stuff you
couldn't use indoors because of the odors of the impurities and
additives outgassing.

In fact, this is one of the issues I have with conservation in
general.  Trade secret chemicals don't belong near artifacts.  They
confuse the treatment history of the items with unknowns.  But the
manufacturers of plastics, fabrics, and paints all have a flock of
trade secret ingredients they use.

I just explain the issue.  I don't have an answer.

Monona


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                  Conservation DistList Instance 27:46
                   Distributed: Tuesday, May 27, 2014
                       Message Id: cdl-27-46-002
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