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Let me discuss further the basis for de-emphasizing the importance of the internal emitter hazard.
There is no direct experience to call upon.
The two nuclear bombs
used during World War II in Japan were detonated at altitudes intended
to maximize blast effects.
fallout was produced.
The weapons were air bursts and no early
Since no other nuclear weapons have been deto-
nated over a city, the basis for predicting the type of fallout that would
be created by ground-bursting a weapon ona target city must be drawn
from the tests in Nevada and the Pacific, and from theoretical and
laboratory studies.
Through such studies, a great deal is now known
about fallout's physical, chemical and radiological properties.
Mathematical models have been developed that simulate the fallout
creation and distribution processes.
Inputs include weapons design
data, meteorological information, and detonation conditions.
Outputs
include not only external gamma dose rates as a function of time and
location in the fallout pattern, but also the density of individual radio-
nuclides per unit area and their solubility.
By the use of electronic
computers, such models are being used to analyze hypothetical nuclear
wars, providing specific estimates of radionuclide concentrations and
their biological availability for any assumed war situation and applicable to any place in the country.
Such models take into account both