[NHCOLL-L:1493] Plastic Bags

[S. Fishman]

I hope this doesn't come across as a silly question, but I really do need to
know.

Our director would like us to change our standards to allow for Dow Zip Lock
(the name brand) heavy duty freezer bags 2.7 mil  for housing.  We are
currently using 4 mil bags that we purchase from archival suppliers (e.g.,
Hollinger).  I understand his thinking, Ziplock bags are cheaper and more
accessible (meaning the grocery store).  I am hesitant to change because we
would be changing from ordering bags from companies that specialize in
dealing with archival supplies.  But, unless I come up with a better reason
than, just because, it will probably change.

I called the Ziplock company to ask for more information and read through a
bit of literature on archival plastic bags.  The bags are polyethylene and
do not contain any plasiticers, corn products, PVC, or DEHA; is that enough
to consider it archival?  The 2.7 mil would not be used for artifacts that
would puncture the bags (e.g., metal, glass, etc.), but is there something
else I am missing as far as thickness is concerned?

Thanks in advance for your comments,

Susan

+++++++++++++++++++++++++++++
Susan Fishman-Armstrong
Laboratory Coordinator
Antonio J. Waring, Jr. Archaeological Laboratory
1600 Maple Street,Carrollton, GA 30118

770-836-4303 (office)
770-838-2577 (fax)