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The Johnson Space Center Water and Food Analytical Laboratory (WAFAL) performed detailed ground-based analyses of archival water samples for verification of the chemical quality of the International Space Station (ISS) potable water supplies for Expeditions 14 and 15. During the 12-month duration of both expeditions, the Space Shuttle docked with the ISS on four occasions to continue construction and deliver additional crew and supplies; however, no Shuttle potable water was transferred to the station during Expedition 14. Russian ground-supplied potable water and potable water from regeneration of humidity condensate were both available onboard the ISS for consumption by the Expeditions 14 and 15 crews. A total of 16 chemical archival water samples were collected with U.S. hardware during Expeditions 14 and 15 and returned on Shuttle flights STS-116 (12A.1), STS-117 (13A), STS-118 (13A.1), and STS-120 (10A) in December 2006, and June, August, and November of 2007, respectively.

The crews of Expeditions 12 and 13 aboard the International Space Station (ISS) continued to rely on potable water from two different sources, regenerated humidity condensate and Russian ground-supplied water. The Space Shuttle launched twice during the 12-months spanning both expeditions and docked with the ISS for delivery of hardware and supplies. However, no Shuttle potable water was transferred to the station during either of these missions. The chemical quality of the ISS onboard potable water supplies was verified by performing ground analyses of archival water samples at the Johnson Space Center (JSC) Water and Food Analytical Laboratory (WAFAL). Since no Shuttle flights launched during Expedition 12 and there was restricted return volume on the Russian Soyuz vehicle, only one chemical archive potable water sample was collected with U.S. hardware and returned during Expedition 12. This sample was collected in March 2006 and returned on Soyuz 11.

During the twelve month period comprising Expeditions 10 and 11, the chemical quality of the potable water onboard the International Space Station (ISS) was verified through the return and ground analysis of water samples. The two-man Expedition 10 crew relied solely on Russian-provided ground water and reclaimed cabin humidity condensate as their sources of potable water. Collection of archival water samples with U.S. hardware has remained extremely restricted since the Columbia tragedy because of very limited return volume on Russian Soyuz vehicles. As a result only two such samples were collected during Expedition 10 and returned on Soyuz 9. The average return sample volume was only 250 milliliters, which limited the breadth of chemical analysis that could be performed. Despite the Space Shuttle vehicle returning to flight in July 2005, only two potable water samples were collected with U.S. hardware during Expedition 11 and returned on Shuttle flight STS-114 (LF1).

Potable water for the Shuttle orbiter is generated as a by-product of electricity production by the fuel cells. Water from the fuel cells flows through a Microbial Check Valve (MCV), which releases biocidal iodine into the water before it enters one of four storage tanks. Potable water is dispensed on-orbit at the rehydration unit of the galley. Due to crew health concerns, iodine removal hardware is installed in the chilled water inlet line to the galley to remove the iodine from the potable water before it is consumed by the crew. The Shuttle water system is sampled to ensure water quality is maintained during all operational phases from the disinfection of the ground servicing equipment through the completion of each mission. This paper describes and summarizes the Shuttle water quality requirements, the servicing of the Shuttle water system, the collection and analysis of Shuttle water samples, and the results of the analyses.

Approximately 50% of the water consumed by International Space Station crewmembers is water recovered from cabin humidity condensate. Condensing heat exchangers in the Russian Service Module (SM) and the United States On-Orbit Segment (USOS) are used to control cabin humidity levels. In the SM, humidity condensate flows directly from the heat exchanger to a water recovery system. In the USOS, a metal bellows tank located in the US Laboratory Module (LAB) collects and stores condensate, which is periodically off-loaded in about 20-liter batches to Contingency Water Containers (CWCs). The CWCs can then be transferred to the SM and connected to a Condensate Feed Unit that pumps the condensate from the CWCs into the water recovery system for processing. Samples of the condensate in the tank are collected during the off-loads and returned to Earth for analyses.

With the Shuttle fleet grounded, limited capability exists to resupply in-flight water quality monitoring hardware onboard the International Space Station (ISS). As such, verification of the chemical quality of the potable water supplies on ISS has depended entirely upon the collection, return, and ground-analysis of archival water samples. Despite the loss of Shuttle-transferred water as a water source, the two-man crews during Expedition 8 and Expedition 9 maintained station operations for nearly a year relying solely on the two remaining sources of potable water; reclaimed humidity condensate and Russian-launched ground water. Archival potable water samples were only collected every 3 to 4 months from the systems that regenerate water from condensate (SRV-K) and distribute stored potable water (SVO-ZV).

Ever since the first crew arrived at the International Space Station (ISS), archival potable water samples have been collected and returned to the ground for detailed chemical analysis in order to verify that the water supplies onboard are suitable for crew consumption. The Columbia tragedy, unfortunately, has had a dramatic impact on continued ISS operations. A major portion of the ISS water supply had previously consisted of Shuttle-transferred water. The other two remaining sources of potable water, i.e., reclaimed humidity condensate and Russian-launched ground water, are together insufficient to maintain 3-person crews. The Expedition 7 crew launched in April of 2003 was, therefore, reduced from three to two persons. Without the Shuttle, resupply of ISS crews and supplies is dependent entirely on Russian launch vehicles (Soyuz and Progress) with severely limited up and down mass.

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.

The early International Space Station (ISS) drinking water supply primarily consists of water recovered from humidity condensate and water transferred from Shuttle. The water is dispensed both from the stored water dispensing system (SVO-ZV) and the galley, which is an integral part of the condensate recovery system. The galley provides both hot and tepid water. An assessment of the quality of each potable water source is underway and consists of periodic collection of samples into Teflon® bags for return to Earth via Shuttle. Water sampling hardware and procedures developed and used during the Shuttle-Mir program are employed on ISS without significant changes. This report provides results from detailed chemical analyses of recovered potable water and supplied (stored) water samples returned from ISS Expeditions 1 through 3. These results have been used to monitor the potability of the product and stored drinking water by comparing the results against water quality standards.

Potable water supplies onboard the International Space Station (ISS) include both reclaimed water from treatment of atmospheric humidity condensate and stored water that is either Shuttle-transferred or ground-supplied. Space station medical operations requirements call for real-time monitoring of key water quality parameters, such as total organic carbon, total inorganic carbon, total carbon, pH, and conductivity, to ensure that crew health is protected from unsafe drinking water. A Total Organic Carbon Analyzer (TOCA) designed to meet these requirements was developed as part of the Crew Health Care System and launched to the ISS in April of 2001. The initial design of the ISS TOCA was previously presented at this conference in 1998. The current design of the instrument includes an improved reagent system and upgraded software to enhance accuracy through the capability to measure organic contamination of the reagents and correct analytical results.

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.

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.

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.

Archival sampling of potable water and condensate for ground laboratory analysis has been an important part of the Shuttle-Mir program because of coolant leaks and other events on Mir that have affected water quality. We report here the development of and preliminary results from a novel device for single phase humidity condensate collection at system pressures. The sampler consists of a commercial-off-the-shelf Teflon® bladder and a custom reinforced Nomex® restraint that is sized properly to absorb the stress of applied pressures. A plastic Luer-Lock disconnect, with poppet actuated by a mating Luer-Lock fitting, prevents the contents from being spilled during transport. In principle, a sampler of any volume can be designed. The empty mass of the reusable one-liter sampler is only 63 grams. Several designs were pressure tested and found to withstand more than 3 atmospheres well in excess of typical spacecraft water or wastewater system pressures.

On the International Space Station (ISS), atmospheric humidity condensate and other waste waters will be recycled and treated to produce potable water for use by the crews. Space station requirements include an on-orbit capability for real-time monitoring of key water quality parameters, such as total organic carbon, total inorganic carbon, total carbon, pH, and conductivity, to ensure that crew health is protected for consumption of reclaimed water. The Crew Health Care System for ISS includes a total organic carbon (TOC) analyzer that is currently being designed to meet this requirement. As part of the effort, a spacecraft TOC analyzer was developed to demonstrate the technology in microgravity and mitigate risks associated with its use on station. This analyzer was successfully tested on Shuttle during the STS-81 mission as a risk mitigation experiment. A total of six ground-prepared test samples and two Mir potable water samples were analyzed in flight during the 10-day mission.

The primary source of potable water planned for the International Space Station will be generated from the reclamation of humidity condensate, urine, and hygiene waters. It is vital to crew health and performance that this reclaimed water be safe for human consumption, and that health risks associated with recycled water consumption be identified and quantified. Only recently has data been available on the chemical constituents in reclaimed waters generated in microgravity. Results for samples collected during Mir-21 reveal that both the reclaimed water and stored water are of potable quality, although the samples did not meet U.S. standards for total organic carbon (TOC), total phenols, and turbidity.

To satisfy a requirement to supply water to Mir station, a process for treating iodinated water on the Shuttle was developed and implemented. The treatment system consists of packed columns for removing iodine and a syringe-based injection system for adding ionic silver, the biocide used in Mir water. Technical and potable grade water is produced and transferred in batches using collapsible 44-liter contingency water containers (CWCs). Silver is added to the water via injection of a solution from preloaded syringes. Minerals are also added to water destined for drinking. During the previous four Shuttle-Mir docking missions a total of 2781 liters (735 gallons) of water produced by the Shuttle fuel cells was processed using this method and transferred to Mir. To verify the quality of the processed water, samples were collected during flight and returned for chemical analysis.

An important milestone in the ongoing effort by NASA to develop and refine closed-loop water recycling systems for human space flight was reached during the summer of 1996 with the successful completion of Phase II of the Lunar Mars Life Support Testing Program at Johnson Space Center. Part of Phase II involved testing a water-recycling system in a closed test chamber continuously occupied by four human subjects for thirty days. The Phase II crew began the test with a supply of water that had been processed and certified for human use. As the test progressed, humidity condensate, urine, and wastewater from personal hygiene and housekeeping activities were reclaimed and reused several times. Samples were collected from various points in the reclamation process during the thirty day test. The data verified the water-processing hardware can reliably remove wastewater contaminants and produce reclaimed water that meets NASA standards for hygiene- and potable-quality water.

On the International Space Station (ISS), humidity condensate will be collected from the atmosphere and treated by multifiltration to produce potable water for use by the crews. Ground-based development tests have demonstrated that multifiltration beds filled with a series of ion-exchange resins and activated carbons can remove many inorganic and organic contaminants effectively from wastewaters. As a precursor to the use of this technology on the ISS, a demonstration of multifiltration treatment under microgravity conditions was undertaken. On the Space Shuttle, humidity condensate from cabin air is recovered in the atmosphere revitalization system, then stored and periodically vented to space vacuum. A Shuttle Condensate Adsorption Device (SCAD) containing sorbent materials similar to those planned for use on the ISS was developed and flown on STS-68 as a continuation of DSO 317, which was flown initially on STS-45 and STS-47.

Iodine depletion in a simulated water storage tank and distribution system was examined to support a larger research program aimed at developing disinfection methods for spacecraft potable water systems. The main objective of this study was to determine the rate of iodine depletion with respect to the surface area of the stainless steel components contacting iodinated water. Two model configurations were tested. The first, representing a storage and distribution system, consisted of a stainless steel bellows tank, a coil of stainless steel tubing and valves to isolate the components. The second represented segments of a water distribution system and consisted of eight individual lengths of 21-6-9 stainless tubing similar to that used in the Shuttle Orbiter. The tubing has a relatively high and constant surface area to volume ratio (S/V) and the bellows tank a lower and variable S/V.