Re: Bioassay

[stabin@esper.com (Mike Stabin)]

Keith Welsh wrote:

>I've got a dumb question:  If normal ops do not exceed the monitoring
>threshold, why are you going to develop a bioassay program?  Would your time
>not be better spent reinforcing the technical bases that you use to show
>that you DONT need to monitor?  What's driving you to do the program even in
>the absence of regulatory requirement?  I'm actually serious because my
>facility is at the same level.  We do not currently have a bioassay program.
>Some would argue we need to do some bioassay just to proove there is not a
>problem.  Is that your approach?

Absolutely.  Many of the source documents in fact (ICRP 54, NCRP 87, some of
the ANSI stds, etc.) give prescriptions for when the thresholds for needing
a program are crossed.  Sometimes a bioassay program consists of
documentation of why one doesn't need one, and this is perfectly legitimate.
Overdoing bioassy to prove the negative may help alleviate fears, or it may
stir them up.  Professional judgement is needed here.  Once you are in an
area of concern (e.g. I think ICRP says something to the effect of having a
time-weighted average air concentration of 0.1 DACs or a maximum at 0.33
DACs - I don't have it in front of me, so the absolute values here may be
off - this is just a fer instance), some sampling must be done, and the
fraction of the workforce monitored should depend on how much above these
limits you find yourself.

Mike Stabin
Radiation Internal Dose
  Information Center
Oak Ridge, TN