[ RadSafe ] Radon Breath Analysis - Simplistic Approach

[Falo, Gerald A Dr KADIX]

Hi all,
 
I was reviewing the 1994 Internal Dosimetry Summer School text and some
history and got to thinking about radon breath analysis to estimate the
Ra-226 body burden. My thoughts were basically as follows. Once the
Ra-226 has come to equilibrium in the body, then the number of radon
atoms produced in any given time interval T is the Ra-226 activity
(A(Ra)) times T. Then if a fraction, f, escape "quickly" (neglecting
radon decay as it transfers to the lungs) to the breath, the number of
radon atoms exhaled over that time interval is f*A(Ra)*T. The
concentration of radon (activity) exhaled is then the radon decay
constant times the number of atoms exhaled divided by the total volume
of air exhaled over time, T.  Finally, the Ra-226 body burden can be
estimated:
 
Radium-226 body burden = (Measured radon concentration)*(Volume of
exhaled air over time interval T)/f*(Rn-decay constant)*T.
 
I'm now wondering if I've oversimplified the issue and am missing some
fundamental aspect of the analysis. Have I missed something? Any replies
can be to me directly, if you think that they would not be of interest
to the list.
 
Thank you for your patience.
 
Jerry
 
________________________________

The statements and opinions expressed herein are my responsibility; no
one else (certainly not my employer) is responsible, but I still reserve
the right to make mistakes.
 
Check core temperature: yes./no? Yes! - Homer Simpson
 
Gerald A. Falo, Ph.D., CHP
Kadix Systems 
U.S. Army Center for Health Promotion and Preventive Medicine - Health
Physics Program
jerry.falo at us.army.mil
410-436-4852