Re: Regulations from scratc

["Mike Bohan" <mike.bohan@yale.edu>]

        Reply to:   RE>>Regulations from scratch-reply to Steve Hand

When training people about radiation risks and limits, I usually like to  use an
analogy to the speed limits on the highways.  The speed limits are set by
society to balance the risks and the magnitude of potential damage at higher
speeds with the benefit of travel.  Radiation limits are set in a similar
manner.  I go on to make the point that many people travel at speeds over the
speed limit without getting into accidents, but travel at speeds less than the
speed limit doesn't automatically assure safety.  I also make the point that the
radiation limits are set very conservatively to begin with and we then apply
ALARA on top of that.  If we apply ALARA to the speed limits we would keep
everyone driving at speeds of 5.5 miles/hour! (At least, here in Connecticut,
6.5 miles/hr in most of the rest of the USA)   I also make the point that nearly
50,000 people are killed/yr in the USA by highway accidents, but we have to
mount extensive epidemiological studies to even attempt to detect a few deaths
from low level radiation effects. 

<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><
Michael J. Bohan, RSO   |  e-mail: mike.bohan@yale.edu
Yale-New Haven Hospital |    Tele: (203) 785-2950
Radiological Physics    |     FAX: (203) 737-4252
20 York St. - WWW 204   |    As usual, everything I say may be plausibly
New Haven, CT    06504  |    denied at my employer's convenience ...
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--------------------------------------
Date: 02/07/96 12:42 PM
To: Mike Bohan
From: radsafe@romulus.ehs.uiuc.edu
I think Frank's statement was intended for the Radsafe audience - i.e. we
know that it means stochastic effects are not "expected" at that dose.  I
agree that when conducting training or other interfaces with employees or
"public" that this qualifier needs to be there.  When I do training, I
follow the same course as Steve and Brian.  We use the conservative
assumption of a stochastic model with non-zero risk at non-zero dose.

Does anyone out there use a different approach during training?  Does anyone
go so far as to say, "there are no effects" i.e. no risk below some dose? 

I personally use a slightly different approach.  After discussing risks and
probabilities (which are subject to the individual filters discussed
occasionally on Radsafe), I do go so far as to ask the question, "Is it safe
to work around radiation?"   This is a little more direct, and something
with a yes or no answer.  Many of us are programed to respond with an answer
that has so many qualifiers in it that you forget what the question was.  I
don't have any problem answering that question with "yes".  And then back
that up with "Is it safe to work in an office (post office???)", or "Is it
safe to ride in a car, fly in a plane, walk down the street......"
Basically, I use the risk estimates to define 'safe', and then it becomes a
matter of the participant's level of trust in the risk estimates.

Anybody have any other tried and true methods that work well for them?

Keith Welch
Thomas Jefferson National Accelerator Facility
Newport News VA
welch@cebaf.gov