ABSTRACT
Fallout measurements were made during Shot Fig
tary significance of fallout contamination from small-yield
to determine mili__ fission weapons.
Results indicate that, when the scaling techniques in TM 23=200 (1957 edition) are extended
to:
ross overestimates of downwind extent are made for H+ 1 hourintensities of
100 T/hr orless.
A dynamic close-in fallout model is presented for yields of 1 to 100 tons, which accounts
for growth and drift of the cloud during its rise and is consistent with Fig measurements of
cloud shine and amount of activity deposited together with dose-rate intensity as functions
of downwind distance.
Calculations using this model are made for
windspeeds of 5, 15, and
30 knots. Intensities greater than 100 r/hr show an increase, whereas intensities less
than 100 r/hr show a decrease in downwind extent with decreasing windspeed. However
the 100-r/hr intensity will extend no farther downwind than 600 to 700 feet
The few measurements of plutonium contamination indicate that no seriouslong-term
problem will result from this source after the nuclear detonation of a small-yield fission
device.
.