B. Physical Dose Estimates for A-bomb Survivors Studies at Chiba, Japan

In-air tissue absorbed ** doses from the primary and scattered radiations of the Hiroshima and Nagasaki atomic bombs, without shielding, were estimated as function of distance from the hypocenters. Gamma-ray dose was determined from the thermoluminescence in bricks and tiles; neutron dose, from 6℃o activity induced in concrete-imbedded iron of buildings. The ratio of the absorbed dose in critical organs to the in-air tissue absorbed dose was determined by phantom measurements using simulated radiation sources for the atomic bombs. The absorbed doses in the thyroid gland, the gonads, and the fetus in útero were thus estimated as a function of distance from the hypocenters. © 1975 Oxford University Press. All rights reserved.