Re: Dose Assessment Turnaround Time

[Elizabeth Brackett <ebracket@freenet.columbus.oh.us>]

On Thu, 29 May 1997, DAVID HARRISON wrote:

> What is, on average, the usual turnaround time 
> to come up with a final dose assessment 
> following an intake of radioactive material?  
> Assume Pu-239.  
> 
> David Harrison 
> DOE LAAO 
> DHARRISON@DOE.LANL.GOV 
>

That depends on a number of factors, but a "final" assessment will never be
quick.  I would guess that most internal dosimetrists would say it was never 
final. Certainly plutonium is going to be one of the more difficult materials
to assess because it is so difficult to detect.  Given that, it will depend
on the material class of the Pu, mode of intake, bioassay lab turnaround
time, among other things.  If the activity in the urine samples drops
below detectable levels immediately the dose assessment will take less time
because there will be little more data to collect (fecal samples are
possible - they're not always easy to get though :) )  It will also depend
on how much variation there is in the data.  Overall, it's very case
dependent but could easily take several months to a year, and in some
cases longer.  Or, it could be "finalized" somewhat quickly but subject to
update as more data are collected.  However, given the past experience at
some facilities, this latter case is not likely to happen because the
internal dosimetrist is blamed if the dose estimate increases.

Liz Brackett


***  Elizabeth M. Brackett, CHP   ***
*** Internal Dosimetry Consultant ***
***        (614) 459-0695         ***
*  ebracket@freenet.columbus.oh.us  *