Re: radiotoxicity of various nuclides

[M.Williamson@mailbox.uq.oz.au (Michael Williamson)]

>I saw a couple postings a while back concerning (I think) contamination
>limits based on the radiotoxicity levels of the isotope.  If I remember, the
>information came from Australia.  Does someone out there have some
>information on this that they could share?  What are the guidance/source
>documents these come from?  Are they based on direct comparisons of ALI's or
>some other simple ratios that could be applied to any given nuclide.   I'm
>particularly interested in electron capture or low beta yield nuclides -
>Be-7, Cr-51, Co-57 etc.
>

I have the NHMRC guideline Alex referred to but it doesnt mention Be7; the
limit for both  Cr51 and Co57 is 1000 Bq/cm2.

This limit is for exposed durfaces in designated areas, including
protective clothing and the skin of radiation workers (sounds a bit high to
me! Personal opinion only).

For the interiors of fume cupboards and glove boxes the limit is relaxed by
a factor of 10 and for undesignated areas and personal clothing, diminished
by a factor of 20.



Michael Williamson
                                        ph +61 7 3365 4504
Radiation Protection Adviser            fax +61 7 3365 1577
Occupational Health & Safety Unit       m.williamson@mailbox.uq.edu.au
University of Queensland
Brisbane 4072
Australia