4-mil is the current federal standard.
> -----Original Message-----
> From: G ALCOCK [SMTP:[log in to unmask]]
> Sent: Wednesday, November 13, 2002 9:40 PM
> To: [log in to unmask]
> Subject: Re: Keep or discard bottle contents?
>
> Aside from the question of keeping the contents...
>
> Why only 2-mil bags? The U.S. National Park Service recommends 4-mil as
> the minimum thickness for archaeological curation (
> <http://www.cr.nps.gov/aad/collections/mgt_02.htm>). I vaguely recall that
> there's info on the Web from the packing industry about the permeability
> of different thicknesses and materials of plastic bags. Perhaps you should
> use thicker bags ... and continue to double-bag, too.
>
> Gwyn
>
> Janna Rudler <[log in to unmask]> wrote:
>
> Hello Everyone-
>
> <snip>
>
> I have taken the precaution, with the olives, of double-bagging the
> bottle in 2 mil poly zip bags.
>
> <snip>
>