Re: High Altitiude Exposures

["CAPT Jerry A. Thomas, MSC, USN" <thomas@bob.usuf2.usuhs.mil>]

Sandy,

        Hope you don't really mean what you said in item #3.  What would be
the meaning of the numbers?  In Dx radiology only localized (e.g.
collimated) areas are exposed.  The Dx x-ray is ordered because the
clinician suspects something and needs radiographic clairification.
Hopefully, the defensive medicine of ordering everything in the book is not
as widely practised as it once was.  THe benefit in this case then far out
weighs the risk and the exposure becomes somewhat meaningless.

        Rx exposures on the other hand are very large as you well know; but
are well collimated and also the dose distribution is well known.  Not sure
again what purpose knowing what the total exposure will mean (e.g. do you
want to track whole body dose, delivered dose to the tumor, bone marrow dose?).

        I would hope that we don't become overly concerned with High
Altitude Exposures and then begin to regulate them.  The airlines will have
a fun time rescheduling their flights around solar flairs to keep their
passengers dose ALARA!

        JERRY THOMAS

At 17:07 12/12/95 -0600, you wrote:
>     Interesting point, however,
>     
>     1. There is no licensee involved (the airlines are not licensed)
>     
>     2. This is all background radiation, and, there are no limits for the  
>        population at large, be it employees or members of the general      
>        public, for natural background, only for exposure was licensed      
>        material.
>     
>     3. I'd be more interested in the general public maintaining their      
>        exposure received from diagnostic or more importantly from          
>        therapeutic procedures.
>     
>     Sandy Perle
>     Supervisor Health Physics
>     Florida Power and Light Company
>     Nuclear Division
>     
>     (407) 694-4219 Office
>     (407) 694-3706 Fax
>     
>     sandy_perle@email.fpl.com
>     
>     HomePage: http://www.lookup.com/homepages/54398/home.html
>
>
>______________________________ Reply Separator
_________________________________
>     
>A while back, a thread ran on exposures to flight attendants and pilots. 
>The mean exposures were between 1-3 mSv/year.  Hmm...this sounds like 
>occupational exposure.  In the world of DOE, these individuals must be 
>monitored for exposure because they exceed 100 mrem/year under typical 
>conditions (10CFR835).  
>     
>Where is the dosimetry?  Where are the exposure records?  Navy Nukes are 
>badged...aren't they?
>     
>Matthew Williamson
>
>
>

CAPT Jerry A. Thomas,  MSC, USN
Chief Radiological Physics
Department of Radiology/Nuclear Medicine
Uniformed Services University of the Health Sciences
4301 Jones Bridge Road
Bethesda, MD  20814-4799

E-mail:  thomas@bob.usuf2.usuhs.mil
Phone:   (301) 295-3246
Fax:        (301) 295-3893