radioactivity. No such subjects were found.

It was concluded therefore as a result of these findings and lack of
findings, that although a measurable quantity of induced radioactivity was
found, it had not been sufficient to cause any harm to persons living in
the two cities after the bombings.



SHIELDING FROM RADIATION


Exact figures on the thicknesses of various substances to provide complete
or partial protection from the effects of radiation in relation to the
distance from the center of explosion, cannot be released at this time.
Studies of collected data are still under way. It can be stated, however,
that at a reasonable distance, say about 1/2 mile from the center of
explosion, protection to persons from radiation injury can be afforded by a
layer of concrete or other material whose thickness does not preclude
reasonable construction.

Radiation ultimately caused the death of the few persons not killed by
other effects and who were fully exposed to the bombs up to a distance of
about 1/2 mile from X. The British Mission has estimated that people in
the open had a 50% chance of surviving the effects of radiation at 3/4 of a
mile from X.



EFFECTS OF THE ATOMIC BOMBINGS ON THE INHABITANTS OF THE BOMBED CITIES