All the corrected G-M tube gamma radiation readings

obtained by the survey team are given in Table 1 for each

measurement site along with all other total exposure rate

data obtained at that site.
Although some beta plus gamma
radiation readings were taken these data were inconsistent
and are not reported.
Thermoluminescent Dosimeters - A large number of thermolumi-

nescent dosimeters (TLD) were used during the survey.
NRDL
contributed the majority of these detectors.
The predominant
type used was a plastic capsule filled with LiF powder and
enclosed in styrofoam inside a small plastic box.
This type
of dosimeter was placed every 100 ft. (measured) along each
of the major transects on Bikini and Eneu Islands.
Total
exposure rate measurements were also made at each site.
The

dosimeters were left in place approximately ten days.

Controls

remained aboard ship.
Both sets were returned to NRDL for
readout after the trip.
The results are given in Table [I in
terms of the net average expcsure rate over the time of

exposure.

There is some question as to whether these dosimeters
were shielded adequately from beta radiation.
This lack of
adequate shieiding might partially explain the slightly
higher average exposure rates obtained from these dosimeters
at survey sites reiative to the other instrumentation at the
same sites.

NRDL also exposed several low background CaF2:Mn

dosimeters at various locations on Bikini and Eneu.
These
dosimeters and controls were returned to the Naval Research
Laboratory in Washington, D. c. for readout.
Although the
metal case surrounding the dosimeter, which is used to
flatten the energy response, should eliminate most of the
B-ray response, these results also appeared to be slightly
higher than results from the other instrumentation.
However,
the total doses to which these dosimeters were exposed were
relatively small and the time between exposure and readout
was quite long.
This resulted in the necessity of subtracting sizeable background readings.
In addition, there
was usually only one dosimeter per monitored location and
thus only one readout available per site.

BOF Arcrimy.
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