the

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RADIATION STANDARDS, INCLUDING FALLOUT

To the best of our knowledge these cases are principally due to
single large accidental exposures rather than to a running steady
accumulation over the years.
Coming now to the case of the experience of the small users here

we could find little or no public data that would give us values needed

by the committee. We examined the most recent data on licensing exrience as reported by the AEC for about a 114-year period ending
ast November. In that period there were some 10,000 licenses in force.
There were 40 radiation incidents reported which you would classify
mostly as being minor in nature. None of them, in fact, reported a
very serious level of radiation exposure.
oing now to the internal deposition which is more difficult to put
into numbers, the nationwide experience in this respect is just not
available. We tried to get some more in our limited survey and the
answers there were interesting in that they showed a nearly complete

absenceof significant deposition cases.

In order to have numbers that we can support better, however, let
me quote the Hanford experience which was: 6,000 man-years of direct
work with one of our most dangerous elements, namely, plutonium,
shows us with only three employees with body burdens of plutonium
approximating or exceeding the present standards. These quantities
are such that none is expected to present any clinically observable
symptoms and none have appeared.
At Hanford, with about 75,000 man-years of experience in working
with other radionuclides, no other internal depositions have occurred
except for a few minor transitory cases involving materials of short
half-life.
The important aspect. of the environmental radiation is what we
contribute to our friends and neighbors around a plant such as we
have at Hanford. Here we can conclude—again without giving
wholly reliable numbers—that persons living in the vicinity of such
installations receive but a small fraction of radiation from these additional sources of that acquired from natural background. In fact,
the contribution there received is for the most part overshadowed by
the contribution from worldwide fallout which I understandis already
regarded as not being very high at this time. As to the average exposure from industrial operations which would relate to the genetically
significant population around the atomic energy plants, if we tried
to spread this over a few million people, we are not able to give precise
numbers but we can give some evidence that it must certainly be only
a small fraction of 1 millirem per person per year. You will recall
the dose from natural background ordinarily falls in the range of 100
to 200 millirem. The gonad dose from fallout in our region, which
is lower than that reported for the Nation at large, is about on the
order of 5 millirem peryear at the present time.
A slightly less favorable aspect refers to situations which mayarise
in the immediate vicinity of any large atomic energy plant such as
ours which lead to doses several times those which currently exist
from fallout. This will arise mainly with individuals with uncommon food habits or other idiosyncracies. It is very hard indeed to
make reliable calculations of what these exposures may be, but using
the best data available to us we have concluded for some time that in
the vicinity of the Hanford project, as an example of the largerscale

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