bombs detonated over Hiroshima and Nagasaki, Japan were detonated high enough above the ground to result in the immediate type of radiation exposure of the people in these cities with little or no fallout occurring. The effect of this type of exposure to penetrating radiation is covered in Chapters 8, 9 and 10. However, when the fireball does touch the surface of the earth large amounts of incinerated earth, water and dabris are sucked up into the bomb cloud and adhere to the radioactive fission and induced products. This mixture of particles settles to earth, in accordance with Stoke's law, for several hundred miles in a downwind. direction. This is designated as the localized or "close-in" type of fallout and is characterized by radiation of much higher intensity than occurs with worldwide fallout. Such a fallout occurred in the Marshall Islands following the experimental detonation of a thermonuclear device at Bikini Island on March 1, 1954. Figure 1 shows a rough map of the fallout area. The following table (Table 1) shows the island groups with degree of involvement. Table 1 Summary of Fallout Exposure Group* Composition Fallout observed Rongelap Ailingnae Rongerik Utirik 64 18 28 157 Heavy (snowlike) Moderate (mistlike) Moderate (mistlike) None Marshallese Marshallese Americans Marshallese Estimated gamma dose(rads) 175 69 78 14 Extent of skin lesions Extensive Less extensive S$light No skin lesions epilat: *Also exposed were 23 Japanese fishermen who received a sublethal dose(Miyoshi and and Kumatori; Koyama; Kumatori et al.). 5007294