RE: 1988 Irradiator Incident

["Grimm, Lawrence" <LGrimm@ADMIN.UCLA.EDU>]

Otto:

As Jim Hardeman pointed out, the irradiator used Cs-137 as the source,
however it was designed NOT for food irradiation, but for medical products
sterilization.  As I am sure that you are aware, the use of Cs-137 (Co-60
being more common) for large scale irradiation is somewhat unusual.  I have
not heard of it being used in food irradiation.   

The Georgia irradiator leak was apparently the result of the following.  The
Cesium was in a chloride form, then double encapsulated in the stainless
steel tube which was about 2 foot long and 3 inch in diameter.  Apparently
the problem was that one Cs-137 tube was not properly manufactured.  It was
deduced that a little moisture was left in the chloride, and internal steam
pressure in the tube caused it to crack.  Being a salt, hydroscopic and in a
pool of water...      

It is nigh on impossible for a Co-60 source, as used in food irradiation, to
leak like a Cs-137 salt.  Therefore, the activists are mixing apples and
oranges as usual. 

PS: don't quote me on the sizes of the tubes.  I am going from memory and
pictures of the sources from a sister irradiator I helped to install in
Colorado.

Larry Grimm
	UCLA EH&S/ Radiation Safety Division
*	lgrimm@admin.ucla.edu   Phone:310/206-0712   Fax: 310/206-9051
*	On Campus: 501 Westwood Plaza, 4th Floor, MS 951605
*	Off Campus: UCLA Radiation Safety Div, 501 Westwood Plaza 4th Fl,
Box 951605, Los Angeles, CA 90095-1605
*	If this email is not RSD business, the opinions are mine, not
UCLA's.
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