fine water drops , thrown from the point of explosion. Rain was observed - fall from the bottom of the surge at -3 min after explosion, and the to spreading slowed down and finally stopped after another 2 min. The mechanism of rain fall-out from the surge is discussed. Theoretical studies of the problem indicate that the fine water droplets should have coagulated to large raindrops by a time which agrees well with that at which rain was observed tn the bottom of the surge. The early stages of droplet growth appear to be controlled by evaporation and condensation of water vapor, but most of the growth is subsequently caused by collisions of droplets of ‘ different size. (D.L.C.) CONTROL; CONFIGURATION; Descriptors: NUCLEAR EXPLOSIONS; LIQUEFYING; FALLOUT; WATER SURFACES; Subject Codes (NSA): HEALTH AND SAFETY 10/5/172 162608 (Item 172 from file: NSA-15-019684 THE ROLE OF WHOLE BODY COUNTERS DISPERSIONS; PARTICLES; EVAPORATION; STEAM; SEA; RAIN; 109) IN THE EVALUATION OF HAZARDS. Radioactivity in Man Bisenbud, M.; Meneely, G.R. ed. New York Univ., Bellevue Medical Center, New York Publication Date: 1961 323-33 p. Publ: Charles C Thomas Journal Announcement: NSA15 Document Type: Book Analytic Language: English Applications of whole-body counting techniques in estimating radiation hazards from internally-deposited radioisotopes are discussed. It is pointed out that whole-body measurements of human radioactivity provide the most accurate method of evaluating hazards from radioactive materials. The status of the Japanese fishermen on the Lucky Dragon and the natives of Rongelap Island exposed to acute fall-out from the thermonuclear explosion of March 1, 1954, are reviewed. Data on internal contamination obtained by analysis of urine are compared with later data obtained on the Marshall Islanders by whole-body counting. It is pointed out that it is not practical to use a whole-body counter immediately following exposure to a massive release of radioactivity, and that whole-body counting should be done only after an extensive period for decontamination and after short-lived radionuclides are no longer dominant. The radioisotopes which present a potential human risk include natural and enriched U Pu>s2/sup >>, /o>s2/sup >>,/a>s2/sup >>,/ Th>s2/sup >>,/nd Sr>s9/sup >./ Most of these radionuclides, with the exception of Ra, do not lend themselves to convenient in vivo determination because the radiations they emit are not sufficiently penetrating. It is concluded that the greatest contribution of the whole-body counter in hazards evaluation lies in studies on the rates and routes by which radionuclides are excreted. (C.H.) Descriptors: ADSORPTION; BODY; CONTAMINATION; COUNTERS; ; DECONTAMINATION; DETECTION; EFFICIENCY; ENRICHMENT; EXCRETION; FALLOUT 7 FISSION PRODUCTS; HALF-LIFE; IN VIVO; MAN; MEASURED VALUES; NUCLEAR EXPLOSIONS; PLUTONIUM 239; POLONIUM 210; QUANTITY RATIO; RADIATION EFFECTS; RADIOACTIVITY; RADIOISOTOPES; RADIUM; RADIUM 226; STRONTIUM 90; THORIUM 232; URANIUM; URINE; USES Subject Codes (NSA): HEALTH AND SAFETY 10/5/173 162607 (Item 173 from file: NSA-15-019683 THE BIOLOGICAL HAZARDS Conard, R.A.; Meneely, OF A FALLOUT FIELD. G.R. Brookhaven National Lab., Publication Date: 1961 Publ: Charles C Thomas 109) ed. Upton, N.Y. 249-65 p. Secondary Report No.: BNL-4720 Note: BNL-4720 Journal Announcement: NSA15 Document Type: Book Analytic Language: English 5 0 0 3 5 8 | Radioactivity in Man