Biological Effectiveness of Ionizing Radiation within Shelters.
Abstract
Direct biological measurements of the total radiation hazard within earth-protected Atomic Energy Commission communal shelters were carried out in five shots of the Upshot-Knothole series. Animals were exposed in thin aluminum and in lead-protected containers in order to estimate the neutron contribution to the total biologically effective dose. Mice and dogs were used. Biological end points employed included mortality, hematology, spleen-thymus weights, gut weights, and uptake of radioactive iron in hematopoietic tissue. Satisfactory correlations between physical measurements of dose and biological effect were obtained. The neutron hazard within shelters having 3 ft 8 in. or more of earth overlay was not appreciable with outside sulfur fluxes 2.4 times 10 to the 11th power n/sq cm or less (a 20-kt weapon at 700 yd), regardless of the incident angle of the bomb radiation. Accurate predictions for greater fluxes or less thickness of earth are not possible from the data. The contribution of neutrons to the total biologically effective dose was found not to increase over the free-air situation following transmission through the earth overlay, and hence gamma is the controlling radiation hazard within shelters exposed to large-diameter implosion weapons. Although significant gamma dose levels were found in certain prototype shelter structures, no statement of the probable degree of hazard is warranted because of probable gamma 'leaks' in the structures studied. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1953
- Accession Number
- ADA077505
Entities
People
- H. H. Hechter
- J. S. Reed
- R. E. Carter
- R. J. Veenstra
- V. P. Bond
Organizations
- Naval Radiological Defense Laboratory