CRLR - 613 - ATTENUATION OF THERMAL RADIATION BY A DISPERSION OF WATER DROPLETS (U). D. Anderson and R. Fullwood, 31 January 1956. UNCLASSIFIED, Special Report (vu) The attenuation of thermal radiation by a plane-parallel water fog is evaluated for a point isotropic source located above the fog. A six-flux approximation to the solution of the transport equation is employed for three dispersion densities and for radiation of wave length 0.2 yp and 3.0 p. Attenuation for water fog is somewhat inferior to that for a similar oi1 fog, and this relative inferiority increases with increasing fog density. The relative effectiveness of water and oil is discussed in terms of attenuation economics and logistics. CRLR - 614 - PROTECTION AFFORDED BY OPERATIONAL SMOKE SCREENS AGAINST THERMAL RADIATION (U). WT-1144, Operation TEAPOT. J. J. Mahoney and E. H. Engquist, November 1955. SECRET-RESTRICTED DATA, Special Report (u) The final report of this work «is WT-1144. CRLR - 616 - ‘TANK AND ARMORED PERSONNEL CARRIER VULNERABILITY TO IONIZING RADIATION (U). Don S. McClelland, 28 March 1956. SECRET-RESTRICTED DATA, Special Report (u) The object of this work was to devise a concept for reducing (u) Theoretical calculations to give the thickness of lead shiela- ag It was found that: the radius of casualty-producing doses of initial radiation from the detonation oF a nuclear weapon to personnel in armored vehicles to the range of moderate damage to the vehicles. ing for garma and graphite or polyethylene shielding for neutrons are presented. weights of these materials to give adequate armored-vehicle protection fcr various situations are given. (1) the crews of armored vehicles are vulnerable to the effects of nuclear weapons at greater distances than the vehicles themselves; (2) at the distance of moderate tank damage, the neutrons from the detonation of a nuclear weapon are more of a personnel hazard to armored vehicle crews than the gamma radiation; (3) the energy spectra for the radiation from a nuclear detonation are insufficiently known to accurately determine the thickness of shielding material required to reduce doses to "safe" levels. This is particularly WNRG