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At least 613 records · Page 34

Emergency cooling analysis for the loss of coolant malfunction

This report examines the dynamic response of a conceptual space power fast-spectrum lithium cooled reactor to the loss of coolant malfunction and several emergency cooling concepts. The results show that, following the loss of primary coolant, the peak temperatures of the center most 73 fuel elements can range from 2556 K to the region of the fuel melting point of 3122 K within 3600 seconds after the start of the accident. Two types of emergency aftercooling concepts were examined: (1) full core open loop cooling and (2) partial core closed loop cooling. The full core open loop concept is a one pass method of supplying lithium to the 247 fuel pins. This method can maintain fuel temperature below the 1611 K transient damage limit but requires a sizable 22,680-kilogram auxiliary lithium supply. The second concept utilizes a redundant internal closed loop to supply lithium to only the central area of each hexagonal fuel array. By using this method and supplying lithium to only the triflute region, fuel temperatures can be held well below the transient damage limit.

Peoples, J. A.↗

Pyrotechnic hazards classification and evaluation program. Run-up reaction testing in pyrotechnic dust suspensions

A preliminary investigation of the parameters included in run-up dust reactions is presented. Two types of tests were conducted: (1) ignition criteria of large bulk pyrotechnic dusts, and (2) optimal run-up conditions of large bulk pyrotechnic dusts. These tests were used to evaluate the order of magnitude and gross scale requirements needed to induce run-up reactions in pyrotechnic dusts and to simulate at reduced scale an accident that occurred in a manufacturing installation. Test results showed that propagation of pyrotechnic dust clouds resulted in a fireball of relatively long duration and large size. In addition, a plane wave front was observed to travel down the length of the gallery.

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Pyrotechnic hazards classification and evaluation program. Phase 2, segment 1: Records and experience analysis

A comprehensive search review and analysis was made of various technical documents relating to both pyrotechnics and high explosives testing, handling, storage, manufacturing, physical and chemical characteristics and accidents and incidents. Of approximately 5000 technical abstracts reviewed, 300 applicable documents were analyzed in detail. These 300 documents were then converted to a subject matrix so that they may be readily referenced for application to the current programs. It was generally concluded that information in several important categories was lacking. Two of the more important categories were in pyrotechnics sensitivity testing and TNT equivalency testing. A general recommendation resulting from this study was that this activity continue and a comprehensive data bank be generated that would allow immediate access to a large volume of pertinent information in a relatively short period of time.

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Pyrotechnic hazards classification and evaluation program. Phase 2, segment 3: Test plan for determining hazards associated with pyrotechnic manufacturing processes

A comprehensive test plan for determining the hazards associated with pyrotechnic manufacturing processes is presented. The rationale for each test is based on a systematic analysis of historical accounts of accidents and a detailed study of the characteristics of each manufacturing process. The most hazardous manufacturing operations have been determined to be pressing, mixing, reaming, and filling. The hazard potential of a given situation is evaluated in terms of the probabilities of initiation, communication, and transition to detonation (ICT). The characteristics which affect the ICT probabilities include the ignition mechanisms which are present either in normal or abnormal operation, the condition and properties of the pyrotechnic material, and the configuration of the processing equipment. Analytic expressions are derived which describe the physical conditions of the system, thus permitting a variety of processes to be evaluated in terms of a small number of experiments.

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Modular space station phase B extension

The system safety analyses and requirements developed for the modular space station during the phase B extension are reviewed. Residual hazards and unresolved safety issues are summarized. Hazards resulting from equipment failures or malfunctions, operations, or credible accidents are identified and evaluated. Special safety trade studies are presented.

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Application of system safety to rail transit systems

Management emphasis on system safety in the rapid transit industry includes the granting and use of funds by the Federal Government according to systematic analysis of safety hazards in advance. Likelihood predictions that those hazards will be activated by exposure of the system to a system failure, a human error, external conditions, or combinations of these aspects determine alternatives to the assumption of risk and recommend corrections before the system is operational. Rigorous safety analyses are projected to assure operational safety for prolonged periods under varied maintenance conditions; these analysis encompass station accident possibilities as well as train-person collisions, car equipment and design, traffic control systems, and tunnel design problems.

Thomas DeW. Styles↗

Designing for auto safety

Safety design features in the motor vehicle and highway construction fields result from systems analysis approach to prevent or lessen death, injury, and property damage results. Systems analysis considers the prevention of crashes, increased survivability in crashes, and prompt medical attention to injuries as well as other postcrash salvage measures. The interface of these system elements with the driver, the vehicle, and the environment shows that action on the vehicle system produces the greatest safety payoff through design modifications. New and amended safety standards developed through hazard analysis technique improved accident statistics in the 70'; these regulations include driver qualifications and countermeasures to identify the chronic drunken driver who is involved in more than two-thirds of all auto deaths.

Elwood T. Driver↗

An altitude chamber rescue ensemble

Altitude chamber tests accomplished with the astronaut crews in the spacecraft at a simulated altitude of above 200,000 ft requires that a rescue team be provided in the event of an accident in the spacecraft. The rescue crew is stationed in an airlock maintained at an altitude of 18,000 ft. A protective ensemble provides the rescue crew with life support capabilities, communications, and protection in the event of an emergency. In the event of an emergency, repressurization of the chamber is initiated; as the chamber descends, the airlock ascends and the two meet at 25,000 ft. This phase of the emergency repressurization takes less than 30 sec.

Lloyd, R. P.↗

Program for the exploitation of unused NASA patents

The program to exploit unused NASA patents through the use of a multidisciplinary approach involving faculty students, and research staff is reported. NASA patents were screened for their applicability outside the space program, specific applications were identified, and the technical and commercial feasibility of these applications was established. Also application of this technology by governmental agencies outside the space program was sought. The program was specifically interested in energy absorbing devices such as those developed for lunar soft landings. These energy absorbing devices absorb large amounts of mechanical energy but are, in general, not reusable. Some of these devices can also operate as structural elements until their structural load capacity is exceeded and they become activated as energy absorbers. The capability of these devices to operate as structural elements and as energy absorbing devices makes them candidates for many applications in the fields of transportation and materials handling safety where accidents take a large toll in human injury and property damage.

Fay, R. J.↗

Mishaps with oxygen in NASA operations.

Oxygen safety programs were conducted, taking into consideration a review of the hazards, the available data concerning the failure of components and systems, and the oxygen handling procedures followed by NASA and its contractors. Information is presented regarding a substantial number of oxygen mishaps together with safety regulations aimed at reducing the accident probability. The information was used to establish categories of events causing the mishap. These categories include materials incompatibility deficiency, materials failure, design deficiency, cleaning deficiency, and procedural deficiencies. Mishaps are generally caused by a number of interacting factors.

Ordin, P. M.↗

Survey of space flight safety systems.

Preventive and remedial conceptual approaches may be employed to enhance the safety of space flight operations. The preventive approach makes use of components of high reliability and the incorporation of redundancy in crew safety-related functions. According to the second conceptual approach the means are to be provided to cope with accidents when they arise. The remedial means include onboard systems, pre-positioned aids, and earth-launched systems. Reports or papers dealing with rescue and survival systems of various types are considered, and a summary of the results of space escape, rescue, and survivability investigations is presented.

Fleisig, R.↗

Manned space flight nuclear system safety. Volume 3: Reactor system preliminary nuclear safety analysis. Part 3: Nuclear Safety Analysis Document (NSAD)

Nuclear safety analysis as applied to a space base mission is presented. The nuclear safety analysis document summarizes the mission and the credible accidents/events which may lead to nuclear hazards to the general public. The radiological effects and associated consequences of the hazards are discussed in detail. The probability of occurrence is combined with the potential number of individuals exposed to or above guideline values to provide a measure of accident and total mission risk. The overall mission risk has been determined to be low with the potential exposure to or above 25 rem limited to less than 4 individuals per every 1000 missions performed. No radiological risk to the general public occurs during the prelaunch phase at KSC. The most significant risks occur from prolonged exposure to reactor debris following land impact generally associated with the disposal phase of the mission where fission product inventories can be high.

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Application of ERTS-A imagery to fracture related mine safety hazards in the coal mining industry

The author has identified the following significant results. The most important result to date is the demonstration of the special value of repetitive ERTS-1 multiband coverage for detecting previously unknown fracture lineaments despite the presence of a deep glacial overburden. The Illinois Basin is largely covered with glacial drift and few rock outcrops are present. A contribution to the geological understanding of Illinois and Indiana has been made. Analysis of ERTS-1 imagery has provided useful information to the State of Indiana concerning the surface mined lands. The contrast between healthy vegetation and bare ground as imaged by Band 7 is sharp and substantial detail can be obtained concerning the extent of disturbed lands, associated water bodies, large haul roads, and extent of mined lands revegetation. Preliminary results of analysis suggest a reasonable correlation between image-detected fractures and mine roof fall accidents for a few areas investigated. ERTS-1 applications to surface mining operations appear probable, but further investigations are required. The likelihood of applying ERTS-1 derived fracture data to improve coal mine safety in the entire Illinois Basin is suggested from studies conducted in Indiana.

Wier, C. E.↗

Manned space programs accident/incident summaries (1963 - 1969)

This summary is a compilation of 508 mishaps assembled from company and NASA records which cover several years of manned space flight activity. The purpose is to provide information to be applied towards accident prevention. The accident/incident summaries are categorized by the following ten systems: cryogenic; electrical; facility/GSE; fuel and propellant; life support; ordnance; pressure; propulsion; structural; and transport/handling. Each accident/incident summary has been summarized by description, cause and recommended preventive action.

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Study of extraterrestrial disposal of radioactive wastes. Part 3: Preliminary feasibility screening study of space disposal of the actinide radioactive wastes with 1 percent and 0.1 percent fission product contamination

A preliminary study was conducted of the feasibility of space disposal of the actinide class of radioactive waste material. This waste was assumed to contain 1 and 0.1 percent residual fission products, since it may not be feasible to completely separate the actinides. The actinides are a small fraction of the total waste but they remain radioactive much longer than the other wastes and must be isolated from human encounter for tens of thousands of years. Results indicate that space disposal is promising but more study is required, particularly in the area of safety. The minimum cost of space transportation would increase the consumer electric utility bill by the order of 1 percent for earth escape and 3 percent for solar escape. The waste package in this phase of the study was designed for normal operating conditions only; the design of next phase of the study will include provisions for accident safety. The number of shuttle launches per year required to dispose of all U.S. generated actinide waste with 0.1 percent residual fission products varies between 3 and 15 in 1985 and between 25 and 110 by 2000. The lower values assume earth escape (solar orbit) and the higher values are for escape from the solar system.

Hyland, R. E.↗

Personal hygienic concerns in long term space flight

Data from numerous experiments and hardware inventories were scanned for Skylab personal hygiene use. A computer program was formulated for predicting the degree of man's involvement with personal hygiene needs. A tabulation was kept for such events as water intake, frequency of urination and defecation, accidents or events requiring clean-up, methods of clean-up, microbiological environment and shower water contamination.

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Summary of the study of disposal of nuclear waste into space

The space shuttle together with expendable and nonexpendable orbital stages such as the space tug or Centaur can safely dispose of waste material by ejecting it from the solar system. The safety problems associated with all phases of launching and operation (normal, emergency, and accident) of such a system are being examined. It appears that solutions can be found that should make the risks acceptable when compared to the benefits to be obtained from the disposal of the nuclear waste. The techniques proposed to make such a system acceptable need to be carefully verified by further study and experiment.

Rom, F. E.↗

Fracture mapping and strip mine inventory in the Midwest by using ERTS-1 imagery

Analysis of the ERTS-1 imagery and high-altitude infrared photography indicates that useful fracture data can be obtained in Indiana and Illinois despite a glacial till cover. ERTS MSS bands 5 and 7 have proven most useful for fracture mapping in coal-bearing rocks in this region. Preliminary results suggest a reasonable correlation between image-detected fractures and mine roof-fall accidents. Information related to surface mined land, such as disturbed area, water bodies, and kind of reclamation, has been derived from the analysis of ERTS imagery.

Wier, C. W.↗