Shipping Question

["Roy A. Parker" <70472.711@compuserve.com>]

> Why would you not take credit for the entire weight of the plate
> source?
     The activity  is plated  or deposited  on the  surface of the disc.
     The 0.002 uCi/g  definition is  based on  specific activity.    The
     specific activity  of a  material  in  which  the  radionuclide  is
     essentially uniformly  distributed is the activity per unit mass of
     material.   The activity  is not  essentially uniformly distributed
     throughout the disc.  Probably all the activity could be removed by
     removing a  few mils  of material  from the  disc.   e.g. One could
     probably remove  a few  mils of  material from the back side of the
     disc and not get any activity.
 
> The source may as well be a piece of metal with fixed contamination,
> in which case you'd have to considered the weight of the entire piece.
     If it is a piece of metal with fixed contamination then the Surface
     Contaminated Object  criteria may  apply and that criteria is based
     on  activity  per  unit  area.    If  the  fixed  contamination  is
     distributed throughout  the piece  of metal  then the  question  of
     essential uniformity would again apply.
 
> Does your logic have anything to do with the fact that the material is
> a "source" (~massless activity) and not just a contaminated item with
> considerable mass?
     No
 
> Would you just go straight to the A2 fractions for LQ and not even
> consider mass?
     I assume by LQ you mean Limited Quantity of Material.  For the
     posed question concerning a plated or electro deposited source I
     would go straight to the Limited Quantity of Material factors
     unless I had some reasonable means of determining the mass or
     specific activity of the plated or deposited material.
 
> Would you just go up in shipping class from LQ straight to RAM n.o.s.
> since A2/g would be neglected?
     I do not understand your question and where A2/g would be revalant.
 
Roy A. Parker, Ph.D.
E-Mail: 70472.711@compuserve.com
Tel: 225-924-1473
Fax: 225-924-4269
-------------( Forwarded computer archived letter follows )-------------
    20-Aug-98 14:45 CDT
From: BRZGV@CCMAIL.CECO.COM (Glen Vickers)
Subject: RE: Shipping Question
 
Why would you not take credit for the entire weight of the plate source?
The activity is inseparable from the plate.  The source may as well be a
piece of metal with fixed contamination, in which case you'd have to
considered the weight of the entire piece.  I understand that when
considering the 0.002 uCi/g you should only consider the material and
not the package.  I can't quite understand the logic with only the
simple sentence supplied.  Further clarification would be helpful.
 
Does your logic have anything to do with the fact that the material is a
"source" (~massless activity) and not just a contaminated item with
considerable mass?  Would you just go straight to the A2 fractions for
LQ and not even consider mass?  Would you just go up in shipping class
from LQ straight to RAM n.o.s. since A2/g would be neglected?  I would
only ship a source as LQ or RAM n.o.s., but would like to understand
some of the logic behind your decisions.
 
Sincerely,
Glen
 

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