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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.

The ability of the water recovery system (WRS) designed for Phase II of the Lunar-Mars Life Support Test Project to remove viral contaminants was tested by challenging the system with bacteriophages MS-2 and PRD-1. Urine-pretreatment and ultrafiltration/reverse osmosis (UF/RO) steps each reduced the combined density of both bacteriophages from >109 to <1 Plaque-Forming Units (PFU)/100 mL. UF/RO also reduced the bacterial density from 108 to 107 Colony-Forming Units (CFU)/100 mL. Before UF/RO, the predominant species of bacteria in the water were Acinetobacter calcoacetious and Klebsiella pneumoniae; afterward, the predominant species were Burkholderia cepacia and B. picketti. The removal of the bacteriophages and the difference in predominant bacteria across the UF/RO step suggest that the Burkholderia had been established downstream of the UF/RO membranes before the test began.

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.

The Crew Health System (CHeCS) plays a pivotal role in monitoring the life-support activities that maintain space station environmental quality and crew safety. Sampling hardware will be used in specific protocols to monitor the microbial dynamics of the closed spacecraft environment. NASA flight experience, ground-based studies, consultations with clinical and environmental microbiologists, and panel discussions with experts in engineering, flight-crew operations, microbiology, toxicology, and water quality systems all have been integral to the revision of in-flight microbial standards. The new standards for air and internal surfaces differentiate between bacterial and fungal loads, unlike previous standards that relied on total microbial counts. Microorganisms that must not be present in air or water or on surfaces also are listed.