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RE: Give Me You Opinion
Scott,
Obviously processing and handling of UF6 requires specialized equipment and
trained personnel. We for instance, use Iconel (high Nickel, high Chrome,
steel alloy) to line reaction vessels and pipes at our UF6-UF4 reduction
facility in SC.
Depending on the situation potential non-rad hazards dominate. In our case
we have a commercial operation where we "deconvert" large quantities of UF6
to UF4. A major concern is the potential for the system to leak hydrogen
fluoride (HF -acid) and resultant exposure to personnel. HF is formed as a
byproduct of reducing UF6 to UF4. Furthermore HF is also produced as a
decomposition byproduct of UF6 hydrolyzing in the presence of water vapor
(in air for instance) to UO2-F2 and HF) Hence our safety and training
programs address these potential scenarios.
However more to the point of the thread, Some work along these lines was
done about a decade ago regarding release of UF6 directly from a rupture
due to heating an overfilled 14 ton cylinder. Look to NUREG 1198 (lessons
learned report) and NUREG/CR-5566, PNL 7328 (health effects) to find all you
might want to know about UF6, and associated hazards from uranium-fluorine
compounds.
Frank J. Vumbaco
VP Health & Safety
Corporate Radiation Safety Officer
Starmet Corporation
2229 Main Street
Concord, MA 01742
voice : 978.369.5410 X 296
fax : 978.371.1677
email: Mailto:vumbaco@starmet.com
> From: Scott D Kniffin
> Reply To: radsafe@romulus.ehs.uiuc.edu
> Sent: Wednesday, January 27, 1999 12:55 PM
> To: Multiple recipients of list
> Subject: Re: Give Me You Opinion
>
> Mike,
>
> Yes the fluorine aspect is the problem for UF6. I had a professor at U of
> Maryland that inhaled some at Oak Ridge in his youth and his voice sounded
> gravely and hoarse all the time from it. Nasty corrosive stuff. Rumor
> has
> it that Teflon was invented/discovered/figured-out-to-be-excellent for
> dealing with UF6 because it ate at the plumbing of the permeable membrane
> gas separators in the early enrichment work. Anyone out there know the
> answer to this? I've always wondered.
>
> Scott Kniffin
>
> RSO Unisys Federal Systems, Lanham, MD
> CHO Radiation Effects Facility, GSFC, NASA
> mailto:Scott.D.Kniffin.1@gsfc.nasa.gov
>
> The opinions expressed here are my own. They do not necessarily represent
> the views of Unisys or NASA. This material has not been reviewed by my
> manager or NASA.
>
> At 10:19 01/27/99 -0600, you wrote:
> >I agree with your response. I do have a question about the UF6. Are you
> >concerned about the fluorine aspect? The specific activity of U238 is
> >180,000 times less than Pu 239. Assuming its all U235, then were talking
> >28000 time lower SA. The biological half lives are 9-15 DAYS for U and
> 200
> >YEARS for Pu. Inhaled U is not a major threat.
> >
> >Of course my own opinion.
> >
> >Mike Dempsey
> >
>
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