was felt to best express the average air-dose received by rersonnel who spent roughly half their tine inside stmictures where the dose rate wa3 later found to be roughly half that outdoors, On the other islands no such shieldiny was present, and no recietion factor was ap plied, The same procedure was followed for all the calculations, TATTLE 8,1 -— Total Ganma Doses Island Dose 3-Hour Fallout r pas | L2—Hour Fallout (r) Ref, 16 (r) pr ea eer ee 106 | 86 70 78 Roagelap 209 | 182 159 17S 81 72 &9 13 12 Ly U tirik 15 | | ( r} ma flonyertki 52 hir-dose ( Point Source of Same Midline Dose a2 r Ailinginae 12-Hour Bilateral Enercy) for Equal | } : 16-Your Fallout (r) 2 130 270°: : 120 F othe 20 *See Section 8.2 8.3 SOFT GAMA AND EETA COMPONENTS In addition to the total body gamna dose, the very soft ganna and higher energy beta radiation from the plane source contributed to the skin dose, Further skin irradiation resulted from local deposits of fallout material on the body surface itself, The latter is impossible to estinate, but the former may be roughly attempted as follows, The beta dose rate in air at a height of 3 feet above the surface of an infinite plane contaminated with nixed 2h-hour-old fission prod- ucts is estimated to be about three times the air carma dose (Reference 1h). The midline ganma dose is approxinately 60 percent of the portion oF ti aad Bae dose Uue VO loceiVY radiation or above ( heterence L3)}e This portion, in tum, is estimated to be 60 percent of the corracted ganma dose measured in air by a calibrated instrument, Tins, the dose. at the surface of a phantom axposed to mixed fission product radiation from an gxternal plane source might be expected to be about eight tines (3/(0.4)*) the midline dose, if both occur at 3 feet off the ground, Such a depth-dose mea surenent has in fact been mace expertnentally ata previous field test (Keference 15), using a phantoa man exposed to toth the initial and resiaqual radiation, The ‘decth=dos es for each situation are shown in Fisure 5,2 with all data as percent of the 3-cn dose, with the diverging initial radiation froa the point of explosion, the exit dose was seea to be 63 percent of the jJ-a1 dose. Out, with the diffuse residual field of fission product radiation, e surface dose 39