( £
and,
would not have the acute emergency character of an attack with atomic bombs,
furthermore, it is unlikely that the enemy would go to the trouble of removing
the gamma emitters from a mixture of radioisotopes just to fool the simpler radiation detection instruments.
It has often been pointed out that the ratio between beta and gamma
intensities encountered in a contaminated area may vary over a very wide range,and
this is used as an argument that the civil defense monitoring instrument must have
some response to beta radiation.
This argument loses much of its weight, however,
when applied to an instrument to be used for a prompt survey whose object is to
determine that an area is clean.
The abnormally high ratios of beta to gamma
activity encountered after the Bikini "Baker" test seem in part to be due to
biological concentration which takes appreciable time (especially in the temperate
zones).
Also, it is very unlikely that, even at the extreme ratios observed, a
"gamma only" instrument would report an area clean when it had a dangerous beta
contamination, since this still would have an easily detectable amount of gamma
with it, not to speak of the bremstrahlung.
Granting the premise that it is important to designate clean areas as
such just as quickly as possible, it is obvious that the radiological monitoring
problem calls for two types of teams in widely differing numbers with different
levels of training and types of equipment.
Merely to avoid confusing these, the
members of those teams whose function is the simple decision that an area is clean
or practically so might be called "radiological wardens," and the term "radiological
surveyors" applied to the better trained and equipped personnel.
The latter would
be able to evaluate dosage from a mixed radiation field, compute permissible
working times for emergency personnel required to operate in affected areas, and
to accompany such personnel to insure their safety in operations involving risk of
really significant exposure (say over 10 r).
‘These comparatively highly trained
surveyors should not have to waste their time on initial survey operations.
They
(or
should be organized on a mobile basis and be at the disposition of the state
-~3-
a
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