Re: What is Weapons Grade

[David W Lee <lee_david_w@lanl.gov>]

RADSAFERS:

I agree that official definitions of weapons grade uranium and weapons 
grade plutonium are both somewhat difficult to find as well as a bit "fuzzy."

Stating that weapons grade U is uranium metal containing at least 93.5% 
U-235 and weapons grade Pu is plutonium (Pu-239) metal containing less that 
6% Pu-240 contamination may be useful.  See U. S. Nuclear Weapons by Chuck 
Hansen, Orion Books, ISBN 0-517-56740-7, 1988.

Best regards  David

At 10:31 AM 8/16/00 -0500, you wrote:
>I think we have all allowed this term to get a sloppy meaning.   To me 
>weapons grade U means a high percentage of U235 such that it will sustain 
>criticality from fast neutrons.  This usually means high purity and no 
>contaminants or poisons  present in the material.
>
>With Plutonium the term seems to be used to indicate some unspecified 
>percentage of Pu239 mixed in with U238, fission products, and 
>Pu238.    Okay,  what makes this mix weapons grade?  To make a weapon out 
>of this requires chemical processing to remove contaminants to the Pu and 
>isotope separation to get rid of the Pu238 and any other non-desirable Pu 
>isotopes.  Either that or careful burn-up times to maximize the Pu 
>239:Pu238 ratio.  What economic factor in a breeder reactor used for fuel 
>production indicates this is taking place?   It is my understanding the 
>maximum Pu yield is from a long burn up and this skews the PU toward Pu238.
>
>Lets use the descriptive language to be descriptive and not sloppy convenient.
>
>Zack Clayton
>Ohio EPA - DERR
>email:  zack.clayton@epa.state.oh.us
>voice:  614-644-3066
>fax:        614-460-8249
>
> >>> "Harmon, Terry O'Devah (ONF) " <onf@bechteljacobs.org> 08/16/00 
> 09:14AM >>>
>The Clinch River Breeder Reactor was supposed to reprocess it and turn it
>into burnable fuel.  The waste portion would have been greatly reduced.
>Unfortunately,  it would also produce a lot of bomb grade material, so
>President Carter scrapped the project.
>
>
>
>************************************************************************
>The RADSAFE Frequently Asked Questions list, archives and subscription
>information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html


************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html