radiotoxicity of various nuclides

[welch@CEBAF.GOV (welch)]

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.

Thanks in advance for any information.

Keith Welch
CEBAF
welch@cebaf.gov
KW