RE: Radiation Biology and Practicing HP?

["David Scherer" <scherer@mirlink.wustl.edu>]

Michael Grissom asks abouth the balance between health and physics in the
profession.  He posits that evaluating radiation risks with respect to
radiobiolgical risk factors is the principal focus of practicing health
physics.  I would like to express a contrary opinion.  I am now working in
diagnostic radiology, and perhaps being away from day-to-day health physics has
given me perspective.  (Or warped my perspective - you decide.)

1.  As a discipline matures, the standards become more established and the
focus shifts toward implementing the standards.  The standards evolve more
slowly and the fundamental basis of the standard has less effect in day-to-day
practice.  Practicing HP's are experts in designing and implementing engineered
and procedural controls for radiation hazards.  But the decision as to what
constitutes a safety hazard has long since been made.  Similarly, IH's don't
decide what the TLV's should be and architects do not rewrite the building code
for each building.  The fundamental decisions about what level of safety is
appropriate are based on research work in related, but distinct, disciplines. 
In my examples these are radiobiology, toxioclogy, and engineering,
respectively.  We should be knowledgeable enough about radioation biology to
keep up with it, but radioation biology is not a subfield of health physics. 
Those areas that relate to design of controls (e.g.rasdiation transport codes)
do rightly receive more emphasis from the profession.

2.  As Melissa Woo pointed out in response, the great bulk of practical health
physics has been defined via regulation.  The creative practice of health
physics comes into play principally in designing new facilities, procedures, or
responding to unplanned incidents.  With this scope of practice, there is
little need for daily reference to radiation biology.

3.  What is behind the comment, it seems to me, is a disagreement with the
standards that have been chosen and the degree to which our practice has been
prescribed by regulation.  These decisions are fundamentally value judgements
by the broader society.  They incorporate a great many competing values -
technical, cultural, economic, moral, etc.  Some of these values can be
analyzed rationally, even mathematically, but some (cultural, religious,
political, etc.) cannot.  As HP's we would like to see _our_ values (i.e.
technical considerations) have more weight.  The values in conflict are
cultural (mistrust of technology) and political (local autonomy). 
Radiobiological experiments are not likely to overcome these conflicting values
in the near term (i.e. my childrens' lifetime).  Instead, the HPS has embarked
on the right course by educating the public and taking part in the decision
making process.  This is more likely to increase our professional autonomy than
reviving classic radiobiology research.

Dave Scherer
scherer@mirlink.wustl.edu