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A general concept of designing an autonomous water system for interplanetary spaceships is proposed. The system features a high reliability resulting from the mutual complement and partial or complete backup of the elements. The system consists of three interconnected subsystems: water-supplies, regenerative physicochemical and biological ones, each providing the crew with water during different stages of a long-term space mission. The system is expected to be a further step in developing a closed-cycle, autonomous, biotechnologies life-support system.

This paper presents a new portable metabolic device (PUMA-Portable Unit for Metabolic Analysis) developed at the NASA Glenn Research Center. PUMA is a battery-operated, wearable unit to measure metabolic rate (minute ventilation, oxygen up-take, carbon dioxide output and heart rate) in a clinical setting, in the field or in remote, extreme environments. The critical sensors in PUMA are located close to the mouth and sampled at 10 Hz to allow intra-breath measurements. PUMA transmits metabolic data wirelessly to a remote computer for data analysis and storage. In addition to it's primary function as a portable metabolic measurement device, the PUMA sensors can also be easily adapted to other applications, including future EVA suits where they could measure metabolic rate for a suited crew member. The first section of the paper discusses the specific technologies and innovations of PUMA.

Monitoring and maintaining biocide concentrations is vital for assuring safe drinking water both in ground and spacecraft applications. Currently, there are no available methods to measure biocide concentrations (i.e., silver ion or iodine) on-orbit. Sensitive, rapid, simple colorimetric methods for the determination of silver(I) and iodine are described. The apparatus consists of a 13-mm extraction disk (Empore® membrane) impregnated with a colorimetric reagent and placed in a plastic filter holder. A Luer tip syringe containing the aqueous sample is attached to the holder and 10 mL of sample is forced through the disk in ∼30 s. Silver(I) is retained by a disk impregnated with 5-(p-dimethylaminobenzylidene)-rhodanine (DMABR), and iodine is retained as a yellow complex on a membrane impregnated with polyvinylpyrrolidone (PVP).

A study is discussed that seeks to collect baseline data from the International Space Station (ISS) Simulator, and in so doing, construct a measuring instrument to assess social states (group functioning) in the extreme environment, as proposed originally by social psychologist Irwin Altman. Six indicators with discrete values would be sampled among crews: 1) numbers of communicative modes, 2) unique communications, 3) efficient communication, 4) cuing behaviors, 5) informal behaviors, and 6) personal evaluations communicated to one another. The indicators would be charted chronologically and on profile at regular intervals, permitting the prediction of psychosocially nominal and off-nominal behaviors. The results of the study can be easily meshed with findings of other studies for a potentially powerful statement about future ISS group functioning.

The Spacesuit Water Membrane Evaporator (SWME) is the baseline heat rejection technology selected for development for the Constellation lunar suit. The first SWME prototype, designed, built, and tested at Johnson Space Center in 1999 used a Teflon hydrophobic porous membrane sheet shaped into an annulus to provide cooling to the coolant loop through water evaporation to the vacuum of space. This present study describes the test methodology and planning to compare the test performance of three commercially available hollow fiber materials as alternatives to the sheet membrane prototype for SWME, in particular, a porous hydrophobic polypropylene, and two variants that employ ion exchange through non-porous hydrophilic modified Nafion. Contamination tests will be performed to probe for sensitivities of the candidate SWME elements to ordinary constituents that are expected to be found in the potable water provided by the vehicle, the target feedwater source.

A description of the largest Acoustic and Vibration Test Facilities in existence for the simulation of major launch vehicle dynamic environment is given and the operational characteristics of both are discussed. Sinusoidal and random excitation techniques are described and unique vibration control methods presented. A comparison of the effects of vibration and acoustic excitation on major space vehicle structures is made.

This paper presents an analysis of potential methods for the testing of Space Shuttle Main Engine turbopump assemblies in a modified Component Test Facility at Stennis Space Center. In particular, the test methods will support long-duration (approximately 250 seconds) green run (acceptance) tests. Six potential test methods were considered, including the traditional, fully pressure-fed test method, some test methods involving engine systems, and some test methods involving recirculation of the pump outlet flow, or “bootstrapping.” Two of these methods were investigated in sufficient detail to provide ROM cost estimates: the fully pressure-fed method, and one of the bootstrap methods.

Typical calculations of radiation exposures in space approximate the composition of the human body by a single material, typically Aluminum or water. A further approximation is made with regard to body size by using a single anatomical model to represent people of all sizes. A comparison of calculations of organ dose and dose-equivalent is presented. Calculations are first performed approximating body materials by water equivalent thickness', and then using a more accurate representation of materials present in the body. In each case of material representation, a further comparison is presented of calculations performed modeling people of different sizes.

Archived water samples collected on the International Space Station (ISS) and returned to Earth for analysis have, in a few instances, contained trace levels of heavy metals. Building on our previous advances using Colorimetric Solid Phase Extraction (C-SPE) as a biocide monitoring technique [1, 2], we are devising methods for the low level monitoring of nickel(II), lead(II) and other heavy metals. C-SPE is a sorption-spectrophotometric platform based on the extraction of analytes onto a membrane impregnated with a colorimetric reagent that are then quantified on the surface of the membrane using a diffuse reflectance spectrophotometer. Along these lines, we have analyzed nickel(II) via complexation with dimethylglyoxime (DMG) and begun to examine the analysis of lead(II) by its reaction with 2,5-dimercapto-1, 3, 4-thiadiazole (DMTD) and 4-(2-pyridylazo)-resorcinol (PAR).

One of the long-standing concerns in space exploration is the presence of trace organic contaminants in recycled spacecraft water supplies. At present, water samples on the International Space Station (ISS) are collected at regular intervals, stored in Teflon™-lined containers, and returned to Earth for characterization. This approach, while effective in defining water quality, has several notable problems. First, this method of archiving removes a significant volume of the ISS water supply. Second, the archived water consumes valuable cargo space in returning Shuttle and Soyuz vehicles. Third, the organic contaminants present in the collected samples may degrade upon extended storage. The latter problem clearly compromises sample integrity. Upon return to Earth, sample degradation is minimized by refrigeration. Due to present resource constraints, however, refrigeration is not a viable option in space.

Humidity condensate collected and processed in-flight is an important component of a space station drinking water supply. Water recovery systems in general are designed to handle finite concentrations of specific chemical components. Previous analyses of condensate derived from spacecraft and ground sources showed considerable variation in composition. Consequently, an investigation was conducted to collect condensate on the Shuttle while the vehicle was docked to Mir, and return the condensate to Earth for testing. This scenario emulates an early ISS configuration during a Shuttle docking, because the atmospheres intermix during docking and the condensate composition should reflect that. During the STS-89 and STS-91 flights, a total volume of 50 liters of condensate was collected and returned. Inorganic and organic chemical analyses were performed on aliquots of the fluid.

Twenty-nine recycled water, eight stored (ground-supplied) water, and twenty-eight humidity condensate samples were collected on board the Mir Space Station during the Phase One Program (1995-1998). These samples were analyzed to determine potability of the recycled and ground-supplied water, to support the development of water quality monitoring procedures and standards, and to assist in the development of water reclamation hardware. This paper describes and summarizes the results of these analyses and lists the lessons learned from this project. Results show that the recycled water and stored water on board Mir, in general, met NASA, Russian Space Agency (RSA), and U.S. Environmental Protection Agency (EPA) standards.

Colorimetric-solid phase extraction (C-SPE) is being developed as a method for in-flight monitoring of spacecraft water quality. C-SPE is based on measuring the change in the diffuse reflectance spectrum of indicator disks following exposure to a water sample. Previous microgravity testing has shown that air bubbles suspended in water samples can cause uncertainty in the volume of liquid passed through the disks, leading to errors in the determination of water quality parameter concentrations. We report here the results of a recent series of C-9 microgravity experiments designed to evaluate manual manipulation as a means to collect bubble-free water samples of specified volumes from water sample bags containing up to 47% air. The effectiveness of manual manipulation was verified by comparing the results from C-SPE analyses of silver(I) and iodine performed in-flight using samples collected and debubbled in microgravity to those performed on-ground using bubble-free samples.

Sampling and retrospective analysis of contaminant volatile organic compounds (VOCs) in submarine atmospheres is essential to demonstrate compliance with exposure standards, evaluate trends, and determine new compounds introduced into the atmosphere of a submarine. Currently atmospheric VOCs are sampled using Tenax™ sorbent tubes and analysed retrospectively. In order to evaluate the efficacy of the sampling regime, submarine trials were conducted using the Volatile Organics Analyzer (VOA), borrowed from NASA. Using the results from these trials further investigative work was carried out to develop the sampling and retrospective analysis regime including passive samplers. This paper will detail findings from VOA trials, and the development of a new passive sampling regime utilising various sorption tubes.

Two portable, collapsible water storage containers were developed to enable water logistics and storage on ISS. The first is a new version of the 44-liter Contingency Water Container (CWC) originally developed for the Shuttle Program. The new CWC uses a thicker Combitherm® film, VPCXX 140, as the bladder material. The second is a multipurpose 10-liter vessel, known as the Payload Water Reservoir (PWR), with a Teflon® bladder. Both of these collapsible vessels have Nomex® outer restraints for structural support, allowing them to withstand pressurization and resist puncture. The results of material longevity tests, the design and development of the two containers are briefly reported, and current and future water, wastewater, coolant and experiment fluid storage applications for the ISS are described.

The paper discusses the potentialities of the plasmo-ozonocatalytic system of microcontaminants (MC) removal from space orangery atmosphere. Atmosphere contaminated by vapours of MC was vented through a purifier consisted of a plasmochemical, ozonocatalytic and chemosorbed units. It was shown the process of decomposition of contaminants is connected with formation of the strong oxidizing and unequilibrium medium. Kinetic mechanism of plasmochemical decomposition of MC is discussed within the framework of radical mechanism. The paper describes a construction and results of the examination of the new filter for contaminants removal from orangery atmosphere. It was shown a broad potentialities of the filter for using it in the orangery gas recycle system.

The results of a study of interaction effectiveness in the crew under isolation in the ESA EXEMSI 92 campaign are presented. The complexity and original character of the group structure was investigated using the bioengineering system known as the Homeostat apparatus. Even though the crew exhibited complex interaction, it is shown that the Homeostat is suitable for on-line inferring of the crew interaction effectiveness in simulation experiments.

The International Space Station (ISS) drinking water supply consists of water recovered from humidity condensate, water transferred from Shuttle, and groundwater supplied from Russia. The water is dispensed from both the stored water dispensing system (SVO-ZV) and the condensate recovery system (SRV-K) galley. Teflon bags are used periodically to collect potable water samples, which are then transferred to Shuttle for return to Earth. The results from analyses of these samples are used to monitor the potability of the drinking water on board and evaluate the efficiency of the water recovery system. This report provides results from detailed analyses of samples of ISS recovered potable water, Shuttle-supplied water, and ground-supplied water taken during ISS Expeditions 4 and 5. During Expedition 4, processing of U.S. Lab condensate through the Russian condensate recovery system was initiated. Results indicate water recovered from both Service Module and U.S.

Collapsible bladder tanks called Contingency Water Containers (CWCs) have been used to transfer water from the Shuttle to the Mir and the International Space Station (ISS). Because their use as potable water storage on the ISS is planned for years, efforts are underway to improve the containers, including the evaluation of new materials. Combitherm®, a multi-layer plastic film, is a material under evaluation for use as the CWC bag material. It consists of layers of linear low density polyethylene, ethylene-vinyl alcohol copolymer, nylon, and a solvent- free adhesive layer. Long term studies of the quality of water stored in Combitherm bladders indicate a gradual but steady increase in the total organic carbon value. This suggests a leaching or breakdown of an organic component of the Combitherm.

The projected radiation levels within the International Space Station (ISS) have been criticized by the Aerospace Safety Advisory Panel in their report to the NASA Administrator. Methods for optimal reconfiguration and augmentation of the ISS shielding are now being developed. The initial steps are to develop reconfigurable and realistic radiation shield models of the ISS modules, develop computational procedures for the highly anisotropic radiation environment, and implement parametric and organizational optimization procedures. The targets of the redesign process are the crew quarters where the astronauts sleep and determining the effects of ISS shadow shielding of an astronaut in a spacesuit. The ISS model as developed will be reconfigurable to follow the ISS. Swapping internal equipment rack assemblies via location mapping tables will be one option for shield optimization.