[en] In 1972 committees of the United Nations and the US National Academy of Sciencs emphasized the need for organ dose estimates on the Japanese atomic-bomb survivors. These estimates were then supplied by workers in Japan and the US, and they were used with the so-called T65D estimates of a survivor's radiation exposure to assess risk from radiation. Recently the T65D estimates have been questioned, and programs for reassessment of atomic-bomb radiation dosimetry have been started in Japan and the US. As a part of this new effort a mathematical analogue of the human body (or ''mathematical phantom''), to be used in estimating organ doses in adult survivors, is presented here. Recommendations on organ dosimetry for juvenile survivors are also presented and discussed. 57 refs., 10 figs., 6 tabs