Forwarded mail....

[Bruce Busby <bbusby@umich.edu>]

>From the mail bag:

lee_david_w@lanl.gov  writes:


As reflected in past ANSI/NCRP publications (ANSI N1.1-1976; NCRP 48-1976; 
ANSI N542-1977; ANSI N432-1980), the definition of a "sealed radioactive 
source" is basically as follows:  "Radioactive material that is contained in 
a sealed capsule, sealed between layer(s) of nonradioactive material, or 
firmly fixed to a nonradioactive surface by electroplating or other means.  
The confining barrier prevents dispersion of the radioactive material under 
normal and most accidental conditions related to use of the source."  Note 
that this general definition of a "sealed radioactive source" attempts to 
define such a source in terms of merely describing how such sources are MADE 
(radioactive material surrounded by a nonradioactive casing or bonded to a 
nonradioactive substrate), rather than defining such a source in terms of 
how such sources are typically USED.  I would contend that how a sealed 
radioactive source is MADE is of lesser definitional importance than the 
actual USE to which surch sources are put.  Within my DOE contractor 
environment, the problem I have with the above vague definition of a "sealed 
radioactive source" is that the wording of this definition is sufficiently 
vague as to not clearly or explicitly EXCLUDE the following items from 
otherwise falling under the above definition of a "sealed radioactive 
source" even though these items have not traditionally been considered to be 
"sealed sources":

	Nuclear triggers in weapons (Pu surrounded by nonradioactive material)
	Nuclear reactor fuel rods
	Radioisotope thermoelectric generators (RTG's)

My impression is that traditional "sealed radioactive sources" are those 
sources the EMISSIONS from which are typically intended for continued or 
repetitive use as a source of ionizing radiation, such as to check/calibrate 
radiation survey instruments or to radiograph something (pipe weld, etc.))

QUESTION:  Does anyone in the Health Physics net have a definition of a 
"sealed radioactive source" that is better and more clear than that 
specified above?

--The following fields were included in the form (unparsed):

user: David W. Lee
org: Los Alamos National Laboratory
occu: Health Physicist
place: Los Alamos, NM