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As part of NASA’s TransHab inflatable habitat program, a Radiation Shield Water Tank (RSWT) is being developed to provide a safe haven from peak solar particle events. The RSWT will provide an 11 ft. (3.35 m) diameter by 7 ft. (2.13 m) tall “safe haven” with a 2.26 in. (0.0574 m) thick wall of water for astronaut residence during peak solar events. The RSWT also functions as a water processing storage tank and must be capable of being filled and drained at will. Because of the unique shape of the RSWT, standard bellows and bladder designs cannot be used for inventory control. Therefore NASA has developed a bladderless tank where capillary forces govern the positioning of the liquid inventory. A combination of hydrophobic and hydrophilic membranes and wetting surfaces allows the tank to be filled and emptied as desired. In the present work, background on space-borne radiation is presented, the bladderless RSWT concept is described, and its theory of operation is discussed.

Two types of supersonic jets, long and short, were designed for an advanced technology spacesuit ejector. Previously, a sonic jet was used in the ejector to improve its performance by reducing oxygen flow through thejetin order to achieve the required suit circulation. The manufacturing of long and short supersonic jets was a challenge which was met successfully by the Miniature Manufacturing Laboratory at NASA/JSC. The jets were tested and their performance was compared with the sonic jet, and it was found that both jets showed improved performance by achieving higher ejector mass ratios.

Current dosimetric practices do not provide comprehensive classification of high-energy charged particle radiation, so that the ability to adequately project health risk to astronaut crews is limited. To address this shortcoming in dosimetry for Space Station missions, a new generation of active radiation monitors is being developed to supplement traditional dosimetry. One active monitor is a Tissue Equivalent Proportional Counter (TEPC) to measure the linear energy transfer (LET) spectrum of space radiation. Two versions of a second type of active monitor, the Charged Particle Directional Spectrometer (CPDS), will be deployed, one internal and one external to the Station. The CPDS consists of a stack of lithium-drifted silicon detectors used to classify the radiation by particle charge and energy. The comprehensive data set obtained by using the TEPC and the CPDS permits significant improvement in assessing crew radiation exposures.

NASA has unique requirements for the development and application of air quality standards for human space flight. Such standards must take into account the continuous nature of exposures, the possibility of increased susceptibility of crewmembers to the adverse effects of air pollutants because of the stresses of space flight, and the recognition that rescue options may be severely limited in remote habitats. NASA has worked with the National Research Council Committee on Toxicology (NRCCOT) since the early 1990s to set and document appropriate standards. The process has evolved through 2 rounds. The first was to set standards for the space station era, and the second was to set standards for longer stays in space and update the original space station standards. The update was to be driven by new toxicological data and by new methods of risk assessment for predicting safe levels from available data. The last phase of this effort has been completed.