~ Ie
neutralized by the rrogressive redioactive decay.
In addition the transit dose
from the cloud pessing over the atolls could not be estineted,
variables were taken into account and the doses celculated.
All of these
These doses were
consistent with the doses that were actually measured on Rongerik by film that
was stored in refrigerators and by film exposed outside on this atoll.
In view
of this internal consistency it is believed that the dose of radiation on the atolls
4s reasonably accurate,
Details of the calculation of the dose are in the official
report which discusses in detail the probable range in values (ref. 1, Chapter 1)
CRARACTERISTICS OF THE GAMMA R‘DIATION
The fellout material vhen deposited on the ground forned a large planer source
of radiztion,
The energy distribution of the radiation reaching an expesed indiv=
idual is influenced by its passage through the intervening air,
A knowledge of the
inherent gamma spectrum as it emminates from the meterial itself is essential in
order to determine the spectrum that inpinges upon exposed individuelg.
When one
takes into account the spectometric data on the mixed fission products and the
degredation by Compton scattering along the path in air, a dose energy histogram
can be constructed, showing that there are roughly three regions with maxina at
1i0C, 700, and 15CO KEV,
The total exposure is thus the resultant effect of partial
doses from each energy region, making the exposure energy condition significantly
different fron those of radiation therapy, experimental biology or from the prompt
garzra radiation of the bomb,
Details of the characteristics of the exposure ere
diecussed in reference, (Ref, 1, Chapter 1).
THE CRARACTERISTICS CF THE FALLOUT MATERTAL
The fallout meterial consisted predominently of flakes of calcium oxide resulting from the incineration of the ecral.
products were derosited,
as erow like.
Unon the flakes of calciun oxide fission
At Rongelap Atoll the material was visible and described
It stuck to the skin, adhered to the hair and clothes, the vegetation
BOE aRcHives
Le