Re: Ra Gamma Ray constant

[tdc@ehssun.lbl.gov (Ted M. de Castro)]

>>It's 0.83 r/hr per Ci at 1 meter from that encapsulation.
>>It's 746 mr/hr at 1 meter from that source.

Thanks Wade - that is very close to the 0.825 for Ra in Pt - as I would 
expect.

Can you cite a reference for this???

BTW - that is the number I always remembered for the initial strength of 
that source - but lately (since the early 80's) we have been using the Pt 
number since it was the only one we could find docs on.

We may be getting rid of this source anyhow - It also falls into this 
"sealed source" controversy - we can recan the Pu Be sources with an 
additional containment - but if that is done to the Ra source it would 
perturb the spectrum - thus even if it were sent it NIST for recal - it 
would no longer be truely Ra and thus would be useless as a primary 
standard.

Too bad - it is the only primary gamma standard we have!  Our only option 
then would be to get the 105 mg Ra source NIST calibrated - but working with 
such a small source will be highly limiting!!

It is a gross tragedy when such regulation interferes with "doing it right". 
ESPECIALLY when the very definition of Non Reactor Nuclear Facility as 
written in the law itself SPECIFICALLY classifies calibration as incidental 
use and therefore NOT within the NRNF catagory.  DOE however is chosing to 
use a "working definition" as calibration with sealed sources.  AND the lab 
has agreed not to disagree with whatever interpretation.

They put all the orders into fed law so as to impose criminal penalties and 
give the orders more force - yet they don't seem to understand that it 
SHOULD limit them to the letter of the law as well.

It would NEVER stand up in court - but it will also never be tested.

Just a little bit of reason from someone high enough up in DOE to make it 
stick - would sure go a long ways toward eliminating a LOT of grief here and 
saving lots of tax payer money!