No Subject

["J. J. Rozental" <josrozen@netmedia.net.il>]

Only one remark about three previous statement:

However still remain the question: -- For  what reason the value 2 nCi/g was
choosen?

	It was discussed in the early 1950 by the ICRP and later, 1958,  accepted
by IAEA, before the first Safety Series n# 6 was written,  the value of
0.002 uCi per gram of  material or a total activity in the working area less
than 0.1 uCi as the below limit to define the meaning of radioactive
material. This lower limit  of 2 nCi/g was  considered taking into account
the most dangerous natural radionuclide at that time,  Ra-226. Only Three
radionuclide at that time were considered as being of  very high
radiotoxicity: Sr-90, Ra and Pu. So that value was, and still is, a
conservative value. 

J. J. Rozental <josrozen@netmedia.net.il>
Consultant, Radiation Safety & Regulation for
Developing Country

<From: INTERNET:JHageman@swri.edu
 

<Please, what is the DOT reference for the 0.002 microcuries per gram?
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<From: "Roy A. Parker" <70472.711@CompuServe.COM>


<Let me attempt to address these issues in reverse order.
 
<1. >Please, what  is the  DOT reference  for the  0.002 microcuries  per
   gram?
 
   49 CFR  173.403(y) Radioactive  material means  any material having a
   specific activity  greater than  0.002 microcuries  per gram  (uCi/g)
   (see definition of specific activity).
 
   This is  obtained from  IAEA Safety  Series No. 6 Regulations for the
   Safe Transport of Radioactive Material, 1985 Edition as amended 1990.
 
   It should  be noted  that in  the recently published successor to the
   above reference,  IAEA Safety  Series ST-1  Regulations for  the Safe
   Transport of  Radioactive  Material  1996  Edition  that  radioactive
   material exempt  from transport  regulations is  based on  a specific
   activity (Bq/g)  for each  individual radionuclide  and  on  a  total
   activity (Bq)  for each  consignment,  which  means  any  package  or
   packages or load of radioactive material presented by a consignor for
   transport.   (This new  definition is  going to cause some problems.)
   It will  probably be  at  least  a  year  or  two  before  this  hits
   regulations and much longer than that for the US.
 ==================================================================== 


<From: roger.gelder@nrpb.org.uk (Roger Gelder)

And once DOT catches up with IAEA Safety Standards ST-1 (1996 Ed)
- the replacement for Safety Series No.6 - you will enjoy a whole 
range of exemption values, depending on nuclide.

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