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FOR RSLSASE 2:30 F.M. (EDT),
FRIDAY, OCTOBER 12, 1956
Remarks Prevared by Dr. Willard F. Libby, Commissioner
United States atomic Enargy Commission
For Delivery befora the American Association for the
Advancement of Science, Washington, D. C.
Friday, October 12, 1956
CURRSNT RESEARCH FINDINGS
ON RADIOACTIVE FALLOUT
I.
iwTRODUCTION
The radioactivity produced by the fission reaction, being due to a rifstira of many different fission
prouucts, changes its charact2ristics continuously and
radidly following release by the bomb detonation. So,
the conditions of firing are of extreme importance in
determining the fallout effects. The intensity of
radiation is enormously greater soon after the detona-
tions, decreasing about tenfold for every sevenfold incrsxs2 in age. Since the time required for ingestion
into the body is long, ingestion is unlikely for the
snorter-lived fission vroducts end therefore the
princical hazards for close-in fallout are radiation
exposures by gamma radiaticn of the whole body and by
beta radiation on the sxin.
In the Longer times, weeks and months after
the explosion, the ingestive hazards begin to become
(more)