.
gumme,
to plaques containing different racioisoto;es.
8
Fertinent dats are abstracted
as follows!
Surface Dose Recuired to Iroduce
Reoognisable Transepidermal
isotope... Energy.
Yttriun’+
Injury (Roentgen~equivalent—
keel
Estimated Amount of
Radiation That Fene=
trated Skin te A Depth
Sreb)
1.53
1,500
1,200
Strontius? 0.61
Yttrim?% 2.20
1,500
1,400
The average
waximum energy of the beta particles from fallout saterial
varies with tiue but will be assumed to be roughly comparebie, in respect to
depth dose, to Yttriux’>
or sr??ny99,
Since the gamua dose at a depth of
7 mg/cm vould not be significantly different from the surface gauna dose,
the ratio of 130
te 1 for beta-gamma vill be esswned at the basal layer of
the eptiderzis.
{one experinent with sheep, using $r%¥90 plaques, shoved that 2500
reps at the plaques' surface produced ulceration in one but net another of
two sheer.®
On the other hand, 1000 rads delivered to tisouedepen ef
7 mg/ez” from a P32 one inch diameter aisleype of eninal not statea} produced
tanning, prolonged erythems and
deuquanation.*#]
It is to be remembered that the above discussion was first based on
gurfaes gamma dose rates whereas the monitors will be making their gama
*"Comparative Study of Experisentally Produced Beta Lesions and Skin Lesions
in Utah Range 5
.
Lushbeugh, C.k., Spalding, JF. and Male, DB, Lash
Wovexber 30, 1953 (UNCLASSIFIZD).
#92We33068 A status report.
Sept. 15, 1954 (COMFIDEMNTIAL).
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