portation, Sineo a survey of all individualsstowed (hat there was Significant contamamaition of skin and clothes, prompt decontamination was instituted, Clothes were removed aud Liundered. Their skin and hare were washed repeatedly with fresh water and soap. In onniasy idividiuals, particukarly on the Marshallese, owas difffeui( te wash (he radioactive: material trom (he ter because of the deavy coconut) ol dai dressing used by these people. Table bot EXPOSED AND CONTROL ONEXPOSED GHOULS ~~ ~ ~~ Approximate Group Designition Total Number in Group Distance from bikini (Naut. Miles) Effective Tine of Fallout 28 [5 H + Gb her AInvricans, Exposed Ronperik + Instrmiment Time of Evacuation Readings Lest Fsthimate Used in Dose lof ‘Total Gaunvena Crlculations Dose in Atrord* H+ 2.5 hr 200 mir “he (8 men) Hoo dave 7TH H+ 34 fr (20 men) Ainerienns, 1s Control Kway American Marshadlesc, bxposed 64 bos H+ 4her Keorpecrtsnge Le 167 HO 270) H+ 4hr H+ 22hr (48 people) H+ 58 br Started at H+ 55 hr Completed ai H+ 78 hr Murshallese, Control $75 mr/hr Ho+ 7 days 175 100 mr ‘he 6y Ha Sle Arhinganac Wtirik H«¢ 60 hr (16 people) H + 9 duys 40 mr/hr 4 H + 8 days 117 Majuro Group Total Exposed — 267 Total Controls - 222 *See Section 1.4.3. 1.4 ESTIMATION OF WHOLE BODY EXTERNAL DOSE The eslimated values of external dose given in Table 1.1 were based on readings of AN PDR-39 field instruments. Averages of a tumber of dose rate measurements on each island ata given time were used. The readings were taken in air, approximately 3 feet above ground, several days after the inhabitants were evacuated. Before this time, adequate surveys with well calibrated instruments had not been possible. Several variables which influence the results are indicated below. These will be discussed in greater detail in un addendum report on external dose, which will contain the data, methods and calculations by which the external dose analysis was made. 1.4.1 Energy Distributionof the Fallout Gamma Radiation,ItsVariation WithTime, the Response of the Meter in Each EnergyRegion andIts Correction Factorfor the Total Dose Spectrum Fallout deposited as an effectively infinite plane source resulted in the dose-energy histogram shown in Fig. 1.2. Its energy distribution was the result of degradation of the original 16