09-21-1994 12:16
5162825311
BNL-MED. DEPT.
P.013
~ll.
neutralized by the progressive radioactive decay.
In addition the transit dose
from the cloud passing over the atolls could not be estinated.
variables were taken into account amd the doses calculated.
All bf these
These
consistent with the doses that vere actually measured on Rongerik
dbses vere
film that
wee stored in refrigerators and by film exmosed outside on this atoll,
Inview
of this internal consistency it 4s believad that the dose of radistibn on the atolls
ia reasonably accurate.
Details of the calculation of the dose are fin the official
report which discusses in detail the probable range in values (ref. ft, Chapter 1)
CRARACTERISTICS OF THE GAMMA R’*DIATION
The fallout material when deposited on the ground formed a lard planar source
of radiation.
The energy distribution of the radiation reaching an exposed indiv=
idual is influenced by its passage through the intervening air.
A kKhowledge of the
Inherent gamma spectrim as 1% emminutes from the mpterdal itself is Psscntiel in
order to ceternine the spectmm that jJnpinces upon exposed sndividuahe.
When one
takes inte account the spectometric data on tha mixed fission producks and the
depredation by Compton scattering along the path in air, a dose enerpy histogram
can be constructed, showing thnt there are roughly three regions with maxima at
100, 700, and 1500 KEV,
The total exposure is thus the resultant effect of partial
dosos from each energy region, making the exposure energy condition Bignificantly
different from those of radiation therapy, experimental bdlology or ffon the prompt
mamma radiation of the bomb,
Details of the characteristics of the posure are
discussed in reference. (Ref. 1, Chapter 1).
THE CHARACTERISTICS CF THE FALLOUT MATERIAL
The fallout meterial consisted predominantly of flakea of calcd} oxide resulting from the incineration of the ccral.
products were deposited.
as enow like.
Upon the flakes of calcium oxide fission
At Rongelap Atoll the material was visidlefand described
It stuck to the skin, adherel to the hair and clothes]
the vegetation -