Re: Polyethylene bags

Where I used to work everything was kept in sealed polyethylene.  A
little research will show you that polyethylene is not an effective
barrier to oxygen (on a small scale - the usually warnings about not
playing with bags over one's head apply) or water vapor, so as long as
you do not have rapid, severe climate (usually temperature) changes in
your storage area, you should not experience condensation.  Most modern
storage areas are built with the idea of minimizing the rate at which
the temp. and rH change, even in the event of a HVAC systems failure, so
this works out OK.

It is an EXCELLENT barrier against dust, oils from groping curatorial
hands, insect activity (won't kill 'em, but will often contain 'em, and
makes droppings or other by-products obvious).  Plus, if your sprinklers
(assuming) ever go off, the worst of the water damage will be minimized,
too.

It is easy to work with, and can be patched together to form larger
containers using a sealing iron.  I used to bag canoes and totem poles.
UV and light exposure did degrade the plastic, causing yellowing and/or
loss of visibility through the bags.  Maybe it makes an OK barrier for
that kind of damage, too?  Perhaps a regular cycle of replacing bags
could provide an appropriate opportunity to review condition and
inventory in general.

There are some mixed opinions, I know, but I think those folks who have
had bad experiences used plastic bags in an uncontrolled environment.
Open bags or bags with holes are probably only a little less effective
at the things I mentioned above.  I found an article somewhere backing
this up - I will send the citation later.

Best wishes!
--
Timothy L. Campbell
[log in to unmask]
http://www.geocities.com/Tokyo/Towers/8189

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