Re: Transportation of Wipes for Removable Contamination

[denison.8@postbox.acs.ohio-state.edu (Eric Denison)]

In article  "Roy A. Parker" <70472.711@CompuServe.COM> writes:

>   The  above   definition  of   radioactive  material   references  the
>   definition for specific activity:
> 
>     173.403(aa)  Specific  activity  of  a  radionuclide,  means  the
>     activity of  the radionuclide per unit mass of that nuclide.  The
>     specific activity  of a  material in  which the  radionuclide  is
>     essentially uniformly  distributed is  the activity per unit mass
>     of the material.

If I understand it correctly, this wording leads me to a couple of 
interesting assumptions:

(a)  if I find a nuclide with an activity less than the microcurie/g limit in 
its pure form, it's not condsidered "radioactive material" and I may possess 
any quantity I choose and do with it whatever I choose;

(b)  if I can arrange to uniformly distribute a radioisotope sample in a mass 
of another medium sufficiently large that the whole lot falls below the SA 
limit, it's not condsidered "radioactive material" and I can do whatever I 
want with it.

Now I'm not sure about (a), but I know good and well that the NRC would have a 
cow or several if we tried to pull off (b).  Let's see -- if we pour this 1 C 
sample of I-129 in a carboy, add a bottle or two of Scintiverse to dissolve, 
then add enough water to form a good firm gelatinous mass that is of 
sufficient size, can we toss it in the regular waste?  Don't think so.

On a more serious note:  according to section 3 of your posting, if I do a 
periodic audit of a lab that uses several nuclides in various quantities and 
perform smear wipes, I have to label the wipes packet, package it for 
transport as if it were destined for a third-party shipper and tag the vehicle 
I use to bring them back to the office?  The idea is patently absurd.

If I find a hot spot during the meter survey, I can be reasonably sure that I 
will have some RAM on one or more of my wipes, but I probably won't be able to 
determine which nuclide I've got, and I certainly won't be able to determine 
the mass of the dust and crud on the wipe and calculate the SA from the meter 
reading.  What if I have a wipe that picked up a 0.1 uCi droplet of a 
tritiated compound?  I'll never find it with a meter, so I have no information 
with which to determine whether I've got a hot wipe or just a piece of dusty 
filter paper.  Same goes for wipes that are only slightly contaminated with 
other nuclides.  A few hundred DPM/100 sq.cm of most nuclides won't show up on 
a meter survey, but the LSC will certainly find it.

Are we to --always-- assume that our wipes are hot, and package them all by 
DOT?  The amount on a single wipe is unlikely to be a hazard to anyone unless 
they eat the wipe, but the time and effort on packaging and labeling the 
wipes for the trip from their lab to ours would be a real pain.  Imagine 
expending the effort to meet DOT on this, re-opening the box 5 minutes later 
to load the samples in the LSC, then finding that all 100 or so of the wipes 
you did that day counted at or below background.  Could make a person crazy.

Eric Denison