SLIDES 48-50 Impact of livingpattern on external whole-body dose. The external radiation exposure rate data were measured by many individuals and an explanation of their methods can be found in their reports (Ch60, He65, Gr77b, JCAES7, Ti8l, USPHS59). A factor of 2.8 x 10° Gy in tissue of interest per nC kg (0.73 rad/R) measured in air at 1 m above the surface was used by us to convert their data to absorbed dose in tissue. This factor was based on several considerations. First, the planar source representedby the flat atoll was assumed by us to be an exponential distribution of Cs activity with depth in soil, typical of aged fallout (Be70). The nature of this source caused minimal variation of absorbed dose with depth or organ; however, the difference in number of electrons per gram of air and per gram of tissue necessitated a correction. Secondly, since the atolls presented a varying exposure rate environment, absorbed dose was adjusted for living pattern variations. Both of these considerations were combined by us to give the above factor used to convert external exposure to absorbed dose in tissue. Specific details on the adjustment for living pattern variation were given by Miltenberger and Greenhouse (Gr77b).