*
.
.
oo
portation, Since a survey of all individuals* showed’ (hat “there was significant contamination ot
skin and clothes, prompt decontamination was instituted. Clothes were removed and laundered.
Their skin and hair were washed repeatedly with fresh water and soap. dn niuany individuals,
perticwiarty om the Marshallese, it was difficult to wash the radioactive materniab from: the hair
because of the heavy coconut. oil hair dressing used by these people.
Table 1a
EXPOSED AND CONTROL UNEXPOSED GROUPS
Approximate
Total
Distance
Effective
Number
in Group
from Bikini
(Naut. Miles)
Time of
Fallout
Aincricans,
Exposed
Rongerik
2u
tas
H+ 6.8 hr
:
Americans,
105
Group
Designation
3#
Timeof
Evacuation
H + 28.5 hr
(8 men)
He 34 hr
Instrument
Readings
Best Estimate
Used in Dose
Calculations
of ‘Total Gamma
Dose in Aira?
200 ur ‘he
H+ 9 days
TH
375 mr/hr
H+ 7 days
175
100 mr/hr
69
(20 men)
Control
Kway American
Marshallese,
bxposed
Rompedip
64
105
Ailuypinge
1B
83
Ulirik
157
Marshalicse,
270
H+4he
H+ 4hr.
H+ 22hr
H+ 50hr
(16 people)
H+ 5thr
(4B people)
H + 54 hr
H+ 9 duys
Started at
40 mr/he
H+ 55 hr
Completed at
H+ 78hr
H + 8 days
14
117
Control
Majuro Group
Total Exposed - 267
Total Controls~ 222
*See Section 1.4.3.
1.4
ESTIMATION OF WHOLE BODY EXTERNAL DOSE
The estimated values of external dose given in Table 1.1 were based on readings of
AN PDR-39 field instruments. Averages of a iumber of dose rate measurements on each
island at a given time were used. The readings were takenin air, approximately 3 feet above
ground, several days after the inhabitants were evacuated, Before this time, adequate surveys
with well calibrated instruments had not been possible.
Several variables which influence the results are indicated below. These will be discussed
in greater detail in an addendum report on external dose, which will contain the data, methods
ind calculations by which the external dose analysis was made.
1.4.1
Energy Distributionof theFalloutGammaRadiation,ItsVariationWithTime, the
Response of the Meter inEach“EnergyRegionaandits Correction Factorfor ‘the Total
DoseSpectrum
Fallout deposited as an effectively infinite plane source resulted in the dose-energy histogram shown in Fig. 1.2. Its energy distribution was the result of degradation of the original
16