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Re: Transportation of Wipes for Removable Contamination



I think Eric is getting NRC & DOT requirements mixed up.  The thread
involves DOT requirements only..


At 07:23 AM 3/31/97 -0600, you wrote:
>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
>
>
>
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