Re: Cs-137 sealed sources

[LIPTONW@detroitedison.com]

--Boundary-1620808-0-0

There is really no such thing as a sealed source; the term is only relative.  
ANY source can leak.  I had a researcher, at a previous job at a DOE facility, 
who had one of those rod sources, where the radioactive material is in an 
epoxy bead and then bonded inside a plastic rod.  If anything is sealed, this 
would be, and the researcher did not consider the possibility of leakage.  I 
found this to be leaking, however.  Unfortunately, when I investigated, I 
found that the researcher had been transporting this source in his personal 
vehicle to another facility, and that the car had since been in an accident 
and been junked; so I ended up surveying a junkyard!   
Bill Lipton 
  


--Boundary-1620808-0-0
X-Orcl-Content-Type: message/rfc822

Received: 25 Feb 1996 21:30:27                    Sent: 25 Feb 1996 20:29:09
From:"root@romulus.ehs.uiuc.edu" <root@romulus.ehs.uiuc.edu>
To: Multiple,recipients,of,list,radsafe@romulus.ehs.uiuc.edu
Subject: Cs-137 sealed sources
Reply-to: radsafe@romulus.ehs.uiuc.edu
X-Orcl-Application: Errors-To:  melissa@romulus.ehs.uiuc.edu
X-Orcl-Application: Originator:  radsafe@romulus.ehs.uiuc.edu
X-Orcl-Application: Sender:  radsafe@romulus.ehs.uiuc.edu
X-Orcl-Application: Precedence:  bulk
X-Orcl-Application: X-Listserver-Version:  6.0 -- UNIX ListServer by Anastasios Kotsikonas
X-Orcl-Application: X-Comment:   Radiation Safety Distribution List 


Dear Radsafers -
I'm hoping to get some information about sealed sources of caesium-137 for
therapy and blood/radiobiology irradiators.  It has been suggested that the
recommended leak testing of the integrity of source encapsulation is partly
because of the (chemical) reactivity of caesium.  Can anyone please point
to a reference for leak tests?  eg the time frame of leak testing -
frequency, time lapse to first test after source manufacture, how long
before there might be problems etc - and methods, direct or indirect. (Not
NRC regs or similar which I may not be able to get hold of).  I would also
be interested to hear any anecdotal information about actual leaks if there
have been any. [No, we don't have a suspect source ourselves.]

Jocelyn Towson
Radiation Safety Officer
Royal Prince Alfred Hospital,Sydney.
jtowson@nucmed.rpa.cs.nsw.gov.au




--Boundary-1620808-0-0--