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The Orion Crew and Service Modules are often compared to the Apollo Command and Service Modules due to their similarity in basic mission objective: both were dedicated to getting a crew to lunar orbit and safely returning them to Earth. Both spacecraft rely on the environmental control, life support and active thermal control systems (ECLS/ATCS) for the basic functions of providing and maintaining a breathable atmosphere, supplying adequate amount of potable water and maintaining the crew and avionics equipment within certified thermal limits. This assessment will evaluate the driving requirements for both programs and highlight similarities and differences. Further, a short comparison of the two system architectures will be examined including a side by side assessment of some selected system's hardware mass.

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).

Experiences during the Shuttle and NASA/Mir programs illustrated the need for a real-time volatile organic analyzer (VOA) to assess the impact of air quality disruptions on the International Space Station (ISS). Toward this end, a joint development by the Toxicology Laboratory at Johnson Space Center and Graseby Dynamics (Watford, UK) produced a 1st generation VOA that has been delivered and is ready for the first 5 years of ISS operation. Criteria for the selection of the 1st generation VOA included minimizing the size, weight, and power consumption while maintaining analytical performance. Consequently, a VOA system based upon gas chromatography/ion mobility spectrometry (GC/IMS) was selected in the mid-90’s. A smaller, less resource-intensive device than the 1st generation VOA will be needed as NASA looks beyond ISS operations. During the past three years, efforts to reduce the size of ion mobility spectrometers have been pursued.

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.

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.

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.

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.

The crew of flight 2A.1 that manned the International Space Station (ISS) assembly mission (STS-96) in May 1999 experienced symptoms that they attributed to poor air quality while working in the ISS modules. Some of these symptoms suggested that an accumulation of carbon dioxide (CO2) in the work area could have contributed to temporary health impacts on the crew. Currently, a fixed-position CO2 monitor in the FGB is the only means of measuring this air contaminant aboard ISS. As a result of this incident, NASA directed the Toxicology Laboratory at Johnson Space Center (JSC) to deliver a portable CO2 monitor for the next ISS assembly mission (STS-101). The Toxicology Laboratory developed performance requirements for a CO2 monitor and surveyed available CO2 monitoring technologies. The selected portable CO2 monitor uses nondispersive infrared spectroscopy for detection. This paper describes this instrument, its operation, and presents the results from ground-based performance testing.

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 active control of problematic microbial populations aboard spacecraft, and within future lunar and planetary habitats is a fundamental Advanced Life Support (ALS) requirement to ensure the long-term protection of crewmembers from infectious disease, and to shield materials and equipment from biofouling and biodegradation. The development of effective antimicrobial coatings and materials is an important first step towards achieving this goal and was the focus of our research. A variety of materials were coated with antibacterial and antifungal agents using covalent linkages. Substrates included both granular media and materials of construction. Granular media may be employed to reduce the number of viable microorganisms within flowing aqueous streams, to inhibit the colonization and formation of biofilms within piping, tubing and instrumentation, and to amplify the biocidal activity of low aqueous iodine concentrations.

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.

Phase separation is one of the most significant obstacles encountered during the development of analytical methods for water quality monitoring in spacecraft environments. Removing air bubbles from water samples prior to analysis is a routine task on earth; however, in the absence of gravity, this routine task becomes extremely difficult. This paper details the development and initial ground testing of liquid metering centrifuge sticks (LMCS), devices designed to collect and meter a known volume of bubble-free water in microgravity. The LMCS uses centrifugal force to eliminate entrapped air and reproducibly meter liquid sample volumes for analysis with Colorimetric Solid Phase Extraction (C-SPE). Previous flight experiments conducted in microgravity conditions aboard the NASA KC-135 aircraft demonstrated that the inability to collect and meter a known volume of water using a syringe was a limiting factor in the accuracy of C-SPE measurements.

One of the proposed methods for monitoring the microbial quality of the water supply aboard the International Space Station is membrane filtration. We adapted this method for space flight by using an off-the-shelf filter unit developed by Millipore. This sealed unit allows liquid to be filtered through a 0.45 μm cellulose acetate filter that sits atop an absorbent pad to which growth medium is added. We combined a tetrazolium dye with R2A medium to allow microbial colonies to be seen easily, and modified the medium to remain stable over 70 weeks at 25°C. This hardware was assembled and tested in the laboratory and during parabolic flight; a modified version was then flown on STS-66. After the STS-66 mission, a back-up plastic syringe and an all-metal syringe pump were added to the kit, and the hardware was used successfully to evaluate water quality aboard the Russian Mir space station.

The water supply for the International Space Station (ISS) consists partially of excess fuel-cell water that is treated on the Shuttle and stored on ISS in 44 L collapsible Contingency Water Containers (CWCs). Iodine is removed from the source water, and silver biocide and mineral concentrates are added by the crewmember while the CWCs are filled. Potable (mineralized) CWCs are earmarked for drinking and food hydration, and technical (non-mineralized) CWCs are reserved for waste system flushing and electrolytic oxygen generation. Representative samples are collected in Teflon® bags and returned to Earth for chemical analysis. The parameters typically measured include pH, conductivity, total organic carbon, iodine, silver, calcium, magnesium, fluoride, trace metals, formate and alcohols. The Nylon monomer caprolactam is also measured and tracked since it is known to leach slowly out of the plastic CWC bladder material.

A sorption-spectrophotometric platform for the concentration and subsequent quantification of biocides in spacecraft drinking water is described. This methodology, termed Colorimetric Solid Phase Extraction (C-SPE), is based on the extraction of analytes onto a membrane impregnated with a colorimetric reagent. Quantification of the extracted analytes is accomplished by interrogating the surface of the membrane with a commercially available diffuse reflectance spectrophotometer. Ground-based experiments have shown that C-SPE is a viable means to determine biocide concentrations in the range commonly found in water samples from the Space Shuttle and the International Space Station (ISS). This paper details efforts to advance C-SPE closer to space flight qualification and ISS implementation, starting with the modification of the ground based biocide detection platform to simplify operation in a microgravity environment.