[ RadSafe ] RE: UN2910 Labeling for EXEMPT Calibration Sources

Dan W McCarn hotgreenchile at gmail.com
Thu Jul 23 13:06:20 CDT 2009

Dear Jim:

Based on the original activities at the time of manufacture, as Cary and
Larry have pointed out, the mixed total activity is 96% of the limit based
on 49CFR173.436. As you point out, this is close to the limit.

When I take the current activity, allowing for decay since manufacture, then
the mixed total activity is 77% of the limit.

Isotope  1/2     Man.  Orig.   Cur.  Lim.   Curr.  Orig.
         Life    Date   Act.   Act.         Frctn  Frctn
Ba133   10.5 y  Dec-07   1    0.897    27   0.033  0.037
Cd109    463 d  Nov-07   1    0.390    27   0.014  0.037
Co57     272 d  Dec-07   1    0.217    27   0.008  0.037
Co60     5.3 y  Dec-07   1    0.807   2.7   0.299  0.370
Cs137     30 y  Sep-08  0.1   0.098  0.27   0.363  0.370
Mn54     312 d  Nov-07   1    0.247    27   0.009  0.037
Na22     2.6 y  Dec-07   1    0.646    27   0.024  0.037
Zn65     244 d  Oct-08   1    0.434    27   0.016  0.037
            Sum mixed activity fractions    0.767  0.963

Dan ii


Dan W McCarn, Geologist
8, Le Buisson Sainte Anne
78860 Saint-Nom-la-Bretèche 
+33.(0). (Land Line) - France) 
+33.(0). (Mobile - France) 
+1-505-240-6872 (Skype - New Mexico)
+353 (0) 76 602 6397  (Skype - Ireland)
HotGreenChile at gmail.com (Private email)

-----Original Message-----
From: Tracy, James W. [mailto:james.tracy at nist.gov] 
Sent: Thursday, July 23, 2009 18:44
To: radsafe at radlab.nl
Cc: hotgreenchile at gmail.com
Subject: UN2910 Labeling for EXEMPT Calibration Sources

Hi Don,

By exempt calibration sources, I assume you mean exempt from NRC licensing.
That has nothing to do with DOT shipping regulations.

For SHIPPING purposes, DOT defines radioactive material as material
containing radionuclides where both the activity concentration AND the total
activity in the consignment exceed the values specified in the table in
49CFR173.436.  Note that since it requires both the activity concentration
and total activity to exceed the value in the table, as long as you meet one
or the other, your shipment qualifies as not radioactive for shipping
purposes.  I normally avoid the concentration limit because it's the
concentration of the radioactive material (ie. You can't place the sources
in a lead pig and use that for your mass).

You will probably want to verify my numbers and check my math, but from
table 49CFR173.436 (activity limits for exempt consignment) the limits for
your isotopes are listed below (I did not include the concentration limits,
but you can look at them if you like)

Cs-137 = 0.27 microcurie
Co-60 = 2.7 microcurie
Ba-133, Cd-109, Co-57, Mn-54, Na-22, Zn-65 = 27 microcurie.

So, if you were shipping only 1 microcurie of Co-60, it would not be
considered radioactive for shipping purposes.  This means there is no
training, no specific packaging, and no labeling that is required.  You can
ship it as if it were a pair of sneakers.  There is a caveat, that the dose
rate on the package must be less than 0.5 mR/hr.  If it exceeds that, then
you will need to ship as limited quantity.

For your specific shipment, assuming you ship all the sources in one package
you will have a mixture.  For mixtures, you will need to use the sum of the
ratios rule (ie. Co60 activity/ Co60 limit + Cs-137 activity/ Cs-137 limit,
+ ...) to determine if your package will be radioactive.  If the ratio is
less than 1, the package is not considered radioactive for shipping
purposes.  For the nuclides and activities you listed below, the sum of the
ratios will be 0.96, so your package will not be considered radioactive for
shipping purposes (provided the dose rate on the surface of the package is
less than 0.5 mR/hr).

Some caveats:  You are close to the limit.  Are your activities really 1.00
microcurie?  I just want to make sure some are not 1.06 microcurie - this
would change the math.  If you don't feel comfortable, being close to the
limit, if you remove either the Co-60 or Cs-137 (each is 0.37 of the limit)
you will be well below the limits.

Lastly, if this is going by air you will need to check the IATA limits.  In
all theory, they should agree with the 49CFR limits, but I did not check
those regulations.  Feel free to email me if you have questions.

Jim Tracy

Message: 1
Date: Wed, 22 Jul 2009 15:49:21 +0200
From: Dan W McCarn <hotgreenchile at gmail.com>
Subject: [ RadSafe ] -
     Yes or     No
To: <radsafe at radlab.nl>
Cc: sales at spectrumtechniques.com
Message-ID: <79BD59F12B9946ADA28C45C035333ED9 at DocHolidayII>
Content-Type: text/plain;     charset="iso-8859-1"

Dear Group:


As I understand it, exempt calibration sources are covered under the UN2910
labeling guidelines; is this correct? Or are they exempt from labeling as

I was just informed that one shipping company does not handle any material
labeled as UN2910.

The sources are labeled on the Spectrum Techniques invoice as CALIBRATION


The activities are as follows:

1.0 uCi Ba-133 ..

1.0 uCi Cd-109 ..

1.0 uCi Co-57 ..

0.1 uCi Cs-137 .. (note that this is the new exempt standard for Cs-137)

1.0 uCi Mn-54 ..

1.0 uCi Na-22 ..

1.0 uCi Co-60 ..

1.0 uCi Zn-65 ..


So? being exempt, do they require labeling?



Dan ii


Dan W McCarn, Geologist
8, Le Buisson Sainte Anne
78860 Saint-Nom-la-Bret?che 
+33.(0). (Land Line) - France) 
+33.(0). (Mobile - France) 
+1-505-240-6872 (Skype - New Mexico) 
+353 (0) 76 602 6397  (Skype - Ireland)
 <mailto:HotGreenChile at gmail.com> HotGreenChile at gmail.com (Private email)



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