Re: Tritium and plastic

["John C. Elliott" <jce@primenet.com>]

At 01:10 PM 1/24/97 -0600, you wrote:
>I remember a while back I asked a question
>regarding tritium permeating through protective
>clothing.  I have another question regarding
>tritium.  Can tritium permeate through plastic
>sample containers?  And if you were going to
>sample for tritium would you use glass or plastic
>sample jars?
>
>Mark P. Winslow
>US EPA - Region II
>
>ps.  This is concerning the "leak" at BNL.
>
>
When I started work at Cal State U Fullerton 20 years ago they had a neutron
generator which employed 8 Ci tritium hydrided on metal foil.  The foils
arrived from the manufacturer in a plastic bag, inside a screw cap glass
jar, inside a sealed tin can (can opener required).  There was 3H removable
contamination on the shelf where they stored the targets, even though the
cans had allegedly wipe tested clean on arrival.  To "eliminate" the
contamination problem, they installed a fiberglass "always on" 200 lfm fume
hood, coated it with stripable paint, placed a gasketed military ammo box in
the hood, and stored the unopened tritium foil containers (no detectable 3H
on arrival) in the ammo box.  Within a year 3 H was detectable on the
outside of the ammo box and on the inside of the hood.  10 years later they
closed the facility and removable 3H was found on the outside of the hood
and on the wall behind the hood, as well as in the hood ducting, all the way
to the roof 6 stories above.  The level of activity (from highest to lowest)
was: Inside glass bottle-->outside glass bottle-->inside can-->outside
can-->inside ammo box-->outside ammo box -->inside hood -->outside
hood-->ceiling over hood-->surface of wall behind hood. 
I also recall a handbook (ICRP?NCRP?) on tritium which said that 3H would
migrate through plastic gloves in 10 minutes or so.

Hope this helps

John Elliott
jce@primenet.com