Jagan, of if partie! shahers are employed, the pereatage of casualties frem theme sourese 6.3 wneehd devwanee endl ened th Coinage 3k redie- tiem damage would trrvesr. The radiation hazard in due ementially en- tirely to the immediate neutron and gamma radiation from the weapon, and exposure to these radiations is only a matter of seconds in duration. Fallout is relatively of no significance.© Than, there in no significant contamination of the skin and, therefore, no beta lesions of the skin. Likewise, there is no significant danger of ingestion or inhalation of radioactive material, and hence, no “internal emitter” problem. Both the immediate gamma and neutron radiations are highly penetrating and will produce acute total body radiation injury in man. The ratio of neutron to gamma ray contribu. tion to the total effective dose at distances of biological significance vanes with weapon type. With mort common shielding materials (earth, concrete), the relative neutron contribution to the total done decreases with passage through the materials. 623 Dependence of Effects on Circumstances of Weapon Detonation The effects previously described were for a high air burt only. With surface. under- yround and underwater bursts of kiloton Werapoos, in addition to blast, heat, and inime- (hate cenizing radiations, serious contamination from fallout can oevur. Its extent would of course be jes than with the “meyaton™ wenpon: however, its yetentinl seriousness can- net be ignored. "Micnitt-aat Jevele of seutron-iaduced radioactivits way he cereent fer a short thine near grand ser. G31 Added Biectss of Megnoa Werpsess lanenecbines Bhost, Mest end Radiatsee Efiocn Were Tae Masston Rowe, the same problew encountered with earlier atomic weapons are alan encountered, only magnified many times. The eres of total destruction, instead of one or two miles in diameter, may extend sev- eral times that far. depending upon the size of the weapon. There are blast, heat and radia- tion casualties as before, and the same problems of ‘andling mass casualties on an unprecelented scale with minimal or no facilities pertain, In addition, the problem of extensive fallout is likely to enter. 6.32 Phenomenology of Fallout Siesaricant Farzoct Rescite only when the tire ball of the bomb comes in contact with the surface of the earth. With the high air burst, midioactivity condenses only on solid particles from the bomb components itself. and on dust nother. The particles are small, are drawn high inte the atmosphere and do not settle tou the earth for periods of days or even mouths. Hy the time they reach the earth's surface, the major part of their radioactivity has been dissipated haridessiy ino the atmos- phere and no sagiiteant hazard results. If, however, the wenpon is detonated on the surface or clo enough so that the fire ball touches the surface, then large amounts of material are drawn up into the bomb cloud. Many of the particles thus formed are heavy enough to deseend rapiddy while stall intensely radioactive. The resalt is a comparatively localized aren of extreme radioactive contamination and a much larger area of some hazard. The fallout area consists, in effect, of n large contaminated plane (except as modified by buildings of other structures), enutting alpha, hete and penetrating gamma rays. It is ap-

Select target paragraph3