SLIDE 38 Field surveys. 35arting in May ba28, Conard and Cohn (Co59), measured wholebody levels of Cs, Zn, and ~-Co in about 100 Rongelap adults, adolescents and juveniles as part of the Brookhaven medical examination program. A ship- borne portable whole-body counter with a standard chair geometry in a shielded steel room was employed (C063). Whole-body counts were obtained in the Rongelap and Utirik populations in 1959 (C060), 1961 (C062), 1965 (C067), 1974 (Co75) and 1977 (Co80a). The counting geometry was converted to a scanning type shadow-shield geometry starting in 1965 (Co67). From 1978 to the present time, whole-body counting measurements were performed with the bed-type shadow shield whole-body counter (Co67). In 1980, a standard chair geometry was once again used. All three counting systems were intercalibrated and also calibrated against the large 54-detector wholebody counter at BNL. Three body burden measurements of the Bikini Island population were conducted from 1974 to 1978 at Bikini Island. In 1980, 1981, 1982, and 1983, whole-body counting of the Enewetak population occurred. Whole-body counting in the field was done from a ship located in the lagoon of the atoll and people were taken to and from shore by small boat. 41