Re: UF6

[rkathren@tricity.wsu.edu (Ron L. Kathren)]

Mike --

Don't know if this will help or not, but typically the IER (i.e. photon)
dose rate from an 'infinite' slab or U is about 10 mrad (100 microGy) per
hour, so the 5 mrem or less value seems to be appropriate.  However, I don't
know about residual materials; one would think the UF6 to be fairly clean
and free of contaminants.  I'll be interested in what you may find out.

Ron Kathren

>I am editing a course on uranium safety.  The draft includes a statement
>about UF6 that I would like to clarify.  I hope some Radsafers can help.
>
>The draft says "Uranium can create widespread low-level gamma radiation
>fields less than 5 mrem/hr.  ... Larger sources of gamma radiation may exist
>from specific processes, including unflushed UF6 cylinders [in which case]
>gamma radiation from residual materials can result in radiation fields of
>several hundred mrem/hr.  This problem can be controlled by flushing empty
>cylinders to remove residual material."
>
>I assume the sentence means that "residual materials" other than UF6 cause
>the "several hundred mrem/hr". If it is UF6 emitting the gammas, I am
>puzzled how gammas from UF6 could be greater than from other forms of U.  
>
>I would be grateful for any clarification.  Thanks, mike
>
>
>