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BLAST BIOLOGY. Technical Progress Report

Description: Experimental data regarding the biologic consequences of exposure to several environmental variations associated with actual and simulated explosive detonations were reviewed. Blast biology is discussed relative to primary, secondary, tentiary, and miscellaneous blast effects as those attributable, respectively, to variations in environmental pressure, trauma from blast-produced missiles (both penetrating and nonpenetrating), the consequences of physical displacement of biological targets by blast-produced winds, and hazards due to ground shock, dust, and thermal phenomena not caused by thermal radiation per se. Primary blast effects were considered, noting physical-biophysical factors contributing to the observed pathophysiology. A simple hydrostatic model was utilized diagrammatically in pointing out possible etiologic mechanisms. The gross biologic response to single. "fast"-rising overpressures were described as was the tolerance of mice, rats, guinea pigs. and rabbits to "long"-duration pressure pulses rising "rapidly" in single and double steps. Data regarding biological response to "slowly" rising over-pressures of "long" duration are discussed. Attention was called to the similarities under certain circumstances between thoracic trauma from nonpenetrating missiles and that noted from air blast. The association between air emboli, increase in lung weight (hemorrhage and edema), and mortality was discussed. Data relevant to the clinical symptoms and therapy of blast injury are presented. The relation of blast hazards to nuclear explosions was assessed and one approach to predicting the maximal potential casualties from blast phenomena is presented making use of arbitrary and tentative criteria. (auth)
Date: September 18, 1959
Creator: White, C.S. & Richmond, D.R.
Partner: UNT Libraries Government Documents Department


Description: A cage containing 20 mice was placed in each of 12 underground shelters in an attempt to assess biologically the inside environment of the shelters. Two samples of 20 mice each acted as controls. The structures, of French and German design, were located at ranges between 840 ft and 4320 ft from Ground Zero. A nuclear device was exploded atop a 700-ft tower and had a yield of 43 kt. All but one group of mice were recovered on D + 2 days. Aside from two samples placed in unrealistic locations, all animals were alive at recovery. With one exception, the peak pressures in the chambers that contained mice were insignificant, ranging from a fraction of 1 psi to 1.6 psi. The one high pressure of 14.4 psi did not kill any of the mice. According to the film-badge dosimeters, one group of mice received 190 r of gamma radiation. The others were exposed to 54 r of gamma or less. The mice were observed for a 60-day postshot period. The deaths that occurred were attributed to a Salmonella infection in the animal colony and not to radiation. Although the gamma radiation doses that most of the animal groups received were low, the levels that existed in the main chambers near the entry doors of the German shelters were over 100 r, a biolog ically significant dose. In constrast, the environment within two of the French shelters appeared to be quite acceptable. (auth)
Date: September 1, 1959
Creator: Richmond, D.R.; White, C.S.; Sanchez, R.T. & Sherping, F.
Partner: UNT Libraries Government Documents Department


Description: Fourteen dogs located on the lee side of planted gravel, of a concrete- block wall, and of glass mounted in the open and in houses were exposed to the environmental variations associated with full-scale nuclear detonations. Aluminum foil was used to protect the animals from thermal effects. The missile environment was monitored through the use of quantitutive missile-trapping techniques. Pressure-time variations in the environment were also recorded. Biologic damage from overpressure and missiles was determined, and the associations between physical envtronmental factors and biologic response were noted and analyzed. The feasibility of utilizing ninssile data, along with other available information from the literature, as a means of quantitutively assesing biologic hazard was estublished by the close correspondence between observed and predicted dangerous wounds. This test provided full-scale validation of procedures and experimsnts worked out chiefly in the laboratory. (auth)
Date: April 1, 1960
Creator: Goldizen, V.C.; Richmond, D.R.; Chiffelle, T.L.; Bowen, I.G. & White, C.S.
Partner: UNT Libraries Government Documents Department


Description: The generation of secondary missiles by blast waves was investigated in Operation Plumbbob for three nuclear detonations with estimated yields of 11, 38, and 44.5 kt. A trapping technique was used to determine the impact velocities for 17,524 missiles (stones, glass fragments, spheres, and military debris or steel fragments) which occurred in open areas, houses, and an underground shelter with an open entryway. The equivalent ideal-wave peak overpressures computed from measured blast data for the open-area stations varied from 3.8 to 21 psi. Two houses and an underground shelter were located where the overpressures were 3.8 and 65 psi, respectively. The effect of hill-and-dale terrain on the production of missiles was investigated on one of the shots. Precursor effects were noted on two of the shots at stations near Ground Zero. Missile velocities measured at all stations except the underground shelter were compared with those computed by use of a model based on an ideal blast wave. An analytical procedure was presented by which translational velocities of nmn can be estimated using the measured velocities of spheres and stones. Total distances of displacement were measured for 145 stones that weighed up to 20 kg and for 1528 fragments from a concrete-block wall. (auth)
Date: February 1, 1962
Creator: Bowen, I.G.; Franklin, M.E.; Fletcher, E.R. & Albright, R.W.
Partner: UNT Libraries Government Documents Department


Description: BS>A theoretical model was developed for the purpose of predicting the motion of objects translated by winds associated with "classical" blast waves produced by explosions. Among the factors omitted from the model for the sake of simplicity were gravity and the friction that may occur between the displaced object and the surface upon which it iritially rested. Numerical solutions were obtained (up to the time when maximum missile velocity occurs) in terms of dimensionless quantities to facilitate application to specific blast situations. The results were computed within arbitrarily chosen limits for blast waves with shock strengths from 0.068 to 1.7 atm (1 to 25 psi at sea level) for displaced objects with aerodynamic characteristics ranging from those of a human being to those of 10-mg stones and for weapon yields at least as small as 1 kt or as large- as 20 Mt. (auth)
Date: January 1, 1961
Creator: Bowen, I.G.; Albright, R.W.; Fletcher, E.R. & White, C.S.
Partner: UNT Libraries Government Documents Department


Description: Thirty-seven sterile materials of common construction usage, common lubricants, and samples of wearing apparel were injected as finely divided particles into the subcutaneous soft tissues of guinea pigs, each in six different sites. At intervals of 3, 7, 14, 21, 30, 65, or 90 days, an inoculation site of each material was excised, in toto, fixed, and examined microscopically. In addition, ten selected materials were injected into the liver and spleen and deposited on the omentum and mesentery of four guinea pigs for each material type. At intervals of 7, 14, 21, and 30 days, one of each group of four animals was sacrificed and a block of tissue containing the inoculum was removed from the tissues and organs, fixed, and examined histologically. The majority of materials induced only a mild and delayed inflammatory response followed by encapsulation at the end of 14 days and a relatively inert fibrous nodule produced by the 2lst or 30th day. Copper particles incited a marked inflammatory response with abscess formation which persisted until the 90th day, although showing signs of subsiding at this time. Cudmium lesions were characterized by a peculiar zone of necrosis about the particle aggregate which persisted until the 60th day. Duraluminum of one type incited a pseudoneoplastic fibrous response. Axle grease, in the early stages, induced one of the most intense acute inflummations, in contrast to that produced by motor oil and ordinary lubricating grease, but the process had subsided and was fibrosed by the end of 30 days. (auth)
Date: October 1, 1957
Creator: Chiffelle, T.L.; Sherping, F.; Goldizen, V.C. & White, C.S.
Partner: UNT Libraries Government Documents Department


Description: The scope and nature of several blast hazards are delineated. Tentative criteria are set forth for threshold damage to humans. These criteria are related 10 nuclear weapons in terms of ground ranges and areas involved for one MT and ten MT surface detonations. To allow appreciation of the relative importance of blast with other effects, appropriate values are noted for ionizing and thermal radiation. Four categories of blast hazards are defined, and the character of each is described. The occurrence of combined injuries from pressure, missiles, and displacement is discussed. Experiences in the Texas City disaster of 1947 are reviewed. Selected data relate environmental conditions to gross biologic damage from overpressures, missiles, and impact loading. 86 references. (C.H.)
Date: September 1, 1959
Creator: White, C.S.
Partner: UNT Libraries Government Documents Department


Description: In two series of experiments 277 experimental animals, including 66 dogs, 52 rabbits, 52 guinea pigs, 63 rats, and 44 mice, were exposed under selected conditions in six different general types of instrumented above- and belowground shelters to blast produced by nuclear explosions. The distance of the several structures from Ground Zero ranged from 1050 to 5500 ft. The most severe alterations in the pressure environment occurring inside the structures followed the detonation of a nuclear device with a yield approximately 50% greater than nominal. The highest overpressure to which animals were exposed was 85.8 psi, the rise time of which was 4 msec. The overpressure endured for about 570 msec. Overpressures ranged from this maximum downward in 15 other exposure situations to a minimum of 1.3 psi enduring for nearly 1346 msec but rising to a maximum in about 420 msec. The latter pressure occurred inside a reinforced concrete bathroom shelter, which was the only surviving part of a house otherwise totally destroyed, at 4700 ft where the outside incident pressure was about 5 psi. Following the nuclear explosions, all animals were recovered, examined, sacrificed, and subjected to gross and microscopic pathological study. All lesions were tabulated and described. The results of pressure-time data, documenting the variations on the pressure environment, are presented and analyzed, and an exploratory attempt is made to relate the alterations in the pressure environment to the associated pathology observed. A critical review of selected material from the blast and related literature is presented. All data are discussed, and the several problems related to the design and construction of protective shelters are noted and briefly, but analytically, assessed. The most outstanding contribution of the field experiments and the related study of the literature was the unequivocal demonstration that the provision of adequate protective structures can ...
Date: October 1, 1956
Creator: White, C.S.; Chiffelle, T.L.; Richmond, D.R.; Lockyear, W.H.; Bowen, I.G.; Goldizen, V.C. et al.
Partner: UNT Libraries Government Documents Department


Description: Dogs, pigs, rabbits, guinea pigs, and mice were exposed to nuclear detonatiors in two open underground pantitioned shelters. The shelters were of similar constructions and each was exposed to separate detonations. Each inner chamber filled through its own orifice; thus four separate pressure enviromments were obtained. An aerodynamic mound was placed over the escape hatch of each structure to determine its effect on the pressurecurve shape inside the chamber. In one test a sieve plate bolted across the top of the mound was evaluated. Wind protective baffles of solid plate and of heavy wire screen were installed in the shelters to compare primary and tertiary blast effects on dogs. The shelters also contained static and dynamic pressure gages, radiation detectors, telemetering devices, and, in one test, air-temperature measuring instruments, dustcollecting trays, and eight pigs for the biological assessment of thermal effects. One dog was severely injured from tertiary blast effects associated with a maximal dynamic pressure (Q) of 10.5 psi, and one was undamaged with a maximal Q of 2 psi. Primary blast effects resulting from peak overpressures of 30.3, 25.5, 9.5. and 4.1 psi were minimal. The mortality was 19 per cent of the mice exposed to a peak pressure of 30.3 psi and 5 and 3 per cent of the guinea pigs and mice exposed to a peak pressure of 25.5 psi. Many of the rabbits, guinea pigs, and mice sustained slight lung hemorrhages at maximum pressures of 25.5 and 30.3 psi. Eardrum perforation data for all species, except mice, were recorded. Following shot 2, thermal effects were noted. Animals of the groups saved for observation have died from ionizing-radiation effects. (auth)
Date: February 1, 1959
Creator: Ricmond, D.R.; Taborelli, R.V.; Bowen, I.G.; Chiffelle, T.L.; Hirsch, F.G.; Longwell, B.B. et al.
Partner: UNT Libraries Government Documents Department