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Re: Shipping to Scotland



Barbara wrote: "Not to throw a wrench in the matter, but if the material
were less than 2 nCi
per gram, it would be "exempt" per DOT, right?"

Barbara L. Hamrick
--------------

What is accepted in USA no necessarly can be accepted by other countries.
The value of the early's 50 of 2 nCi per gram (70 Bq/g) is an example.
The transport regulations have always contained an exemption criterion which
defined materials subject to their requirements. The current regulations
define radioactive material as any material having a specific activity
greater than 70 Bq/g. The IAEA Basic Safety Standards (BSS), Safety Series
115, 1996, however, use a radionuclide-specific approach which leads to
derived exemption values spanning seven orders of magnitude, and straddling
70 Bq/g in the case of activity concentration. The BSS also present
exemption values for total activity quantities (Bq).

It was recognized that the single exemption level of 70 Bq/g has no dose
basis and that it was unlikely that this level satisfied the primary dose
criteron of 10 microsievert in a year for exemption for all radionuclides. A
set of transport-specific scenarios were developed which reflected various
exposure situations (exposure times, distances, source geometries, etc.).
Based on these scenarios, both activity concentration and total activity
values were calculated which would result in meeting the 10 microsievert per
year value. These transport derived values were comparable to the exemption
values in the BSS and resulted in recommended activity concentrations
ranging from 1 to 10E6 Bq/g.

Given the difficulty in technically justifying the 70 Bq/g value and the
similarity in results from the transport scenarios and the BSS scenarios, it
was determined to be preferable to simply adopt the BSS derived exemption
values. Consequently, the regulations contain both activity concentration
and "total activity per consignment" exemption values. For mixtures of
radionuclides, the "ratio rule" must be applied so that the sum of the activ
ities (or activity concentrations) present for each radionuclide divided by
the applicable exemption value is less than or equal to one.

Jose Julio Rozental
joseroze@netvision.net.il
Israel






----- Original Message -----
From: <BLHamrick@aol.com>
To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
Sent: Wednesday, November 22, 2000 5:38 AM
Subject: Re: Shipping to Scotland


In a message dated 11/21/2000 10:33:50 AM Pacific Standard Time,
RoyAParker@compuserve.com writes:

<< You are  the victim  of terminology.   Exempt  quantity  of  radioactive
 material is  a licensing  term and not a transportation term.  There are
 exempt quantities  of all other transportation hazard classes except for
 explosives and radioactive materials.

 You are  meaning excepted package, limited quantity of material.  In the
 transportation world there is a big difference. >>

Not to throw a wrench in the matter, but if the material were less than 2
nCi
per gram, it would be "exempt" per DOT, right?

Barbara L. Hamrick
BLHamrick@aol.com
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