Spikes and chest x-rays

["1LT Philip Hypes"<1lt_philip_hypes_at_chppm8__apgea@chppm-ccmail.apgea.army.mil>]

     I've always had a bit of a problem with the "about as
     much as a chest x-ray" yardstick.  Perhaps it's just
     a comprehension prolem on my part, but it seems to me
     that this comparison is often somewhat inappropriate.
     In this case, whole body irradiation is being compared
     to irradiation of the lungs and surrounding tissue.
     True, there will be some scatter from the field of the
     x-ray, but it hardly constitutes uniform, whole body
     irradiation.  There is also the issue of the type of
     radiation.  For a chest x-ray, you are essentially
     dealing with gamma rays whose energies range from almost
     zero up to 100-120 kV.  I have seen the chest x-ray
     comparison made for exposure to I-131 from fission
     (reactor or weapon).  In that case, you have internal
     uptake of radioactivity, and it probably won't be acute
     in comparison to the chest x-ray.
     
     This comparison is often made in an attempt to help
     members of the general public make some sort of 
     connection between the levels of risk from an incident
     or exposure scenario.  It probably serves that purpose
     fairly well, especially in situations where most HP
     professionals would agree that the health risk is
     minimal.  However, an agitator wouldn't have to do
     much research to turn up the objections I've made here.
     Those promulgating the comparison could be portrayed
     as simplifying the situation, or comparing apples to
     oranges.  I can just hear some blowhard saying "and
     they're supposed to be the 'experts'!"
     
     Comments?
     
     Phil Hypes
     1LT_Philip_Hypes_at_chppm8__apgea@chppm-ccmail.apgea.army.mil
     
     Anyone who may find themselves tempted to reply to the
     above by mailing me a religious chain letter is referred
     to Proverbs 10:19.


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