Debrah K. Plumlee

ISS Expeditions 16 thru 20: Chemical Analysis Results for Potable Water

During the twelve month span of Expeditions 16 and 17 beginning October of 2007, the chemical quality of the potable water onboard the International Space Station (ISS) was verified safe for crew consumption through the return and chemical analysis of water samples by the Water and Food Analytical Laboratory (WAFAL) at Johnson Space Center (JSC). Reclaimed cabin humidity condensate and Russian ground-supplied water were the principle sources of potable water and for the first time, European groundsupplied water was also available. Although water was transferred from Shuttle to ISS during Expeditions 16 and 17, no Shuttle potable water was consumed during this timeframe. A total of 12 potable water samples were collected using U.S. hardware during Expeditions 16 and 17 and returned on Shuttle flights 1E (STS122), 1JA (STS123), and 1J (STS124). The average sample volume was sufficient for complete chemical characterization to be performed. The results of JSC chemical analyses of these potable water samples are presented in this paper. The WAFAL also received potable water samples for analysis from the Russian side collected inflight with Russian hardware, as well as preflight samples of Rodnik potable water delivered to ISS on Russian Progress vehicles 28 to 30. Analytical results for these additional potable water samples are also reported and discussed herein. Although the potable water supplies available during Expeditions 16 and 17 were judged safe for crew consumption, a recent trending of elevated silver levels in the SVOZV water is a concern for longterm consumption and efforts are being made to lower these levels.

Chemical analysis of ISS potable water from expeditions 8 and 9

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). Because of the severely limited down mass on the Russian Soyuz vehicle, only a few potable water samples of less than 250 milliliters were actually returned to the ground with each crew. The chemical analyses that were performed on the returned samples were limited by the small sample volumes. Analytical results for the archival potable water samples returned from Expeditions 8 and 9 are reported in this paper and compared with ISS water quality specifications. Results from analyses of samples collected from the Service Module galleys hot and warm ports during Expeditions 8 and 9 indicated that the ISS system for regeneration of condensate water (SRV-K) produced acceptable quality potable water.

ISS potable water sampling and chemical analysis : Expeditions 6 & 7

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. As a result, the chemical archival sample collection frequency has been temporarily reduced from monthly to quarterly, with a sample volume of only 250 instead of 750 milliliters. This smaller sample volume has necessitated reductions in the number of analyses that can be performed, including turbidity, total dissolved solids, dissolved silver, total iodine, pH, and/or conductivity. This paper reports the analytical results for archival samples of reclaimed condensate and ground-supplied potable water collected during Expeditions 6 and 7 and compares them to ISS water quality standards.

international Space Station Potable Water Quality for Expeditions 26 through 29

International Space Station (ISS) Expeditions 26-29 spanned a 12-month period beginning in November 2010, in which the final 3 flights of the Space Shuttle program finished ISS construction and delivered supplies to support the post-Shuttle era of station operations. Expedition crews relied on several sources of potable water during this period, including water recovered from urine distillate and humidity condensate by the U.S. water processor, water recovered from humidity condensate by the Russian water recovery system, and Russian ground-supplied potable water. Potable water samples were returned during Expeditions 26-29 on Shuttle flights STS-133 (ULF5), STS-134 (ULF6), and STS-135 (ULF7), as well as Soyuz flights 24-27. The chemical quality of the ISS potable water supplies continued to be verified by the Johnson Space Center’s Water and Food Analytical Laboratory by means of analyses of returned water samples. This paper presents the chemical analysis results for water samples returned from Expeditions 26-29 and discusses their compliance with ISS potable water standards. The presence or absence of dimethylsilanediol (DMSD) is specifically addressed, as DMSD was identified as the primary cause of the temporary rise and fall in total organic carbon of the U.S. product water that occurred in the summer of 2010.

Chemical Analysis Results for Potable Water from ISS Expeditions 21 through 25

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 21 to 25. Over a 14-month period, the Space Shuttle visited the ISS on five occasions to complete construction and deliver supplies. The onboard supplies of potable water available for consumption by the Expeditions 21 to 25 crews consisted of Russian ground-supplied potable water, Russian potable water regenerated from humidity condensate, and US potable water recovered from urine distillate and condensate. Chemical archival water samples that were collected with U.S. hardware during Expeditions 21 to 25 were returned on Shuttle flights STS-129 (ULF3), STS-130 (20A), STS-131 (19A), STS-132 (ULF4) and STS-133 (ULF5), as well as on Soyuz flights 19-22. This paper reports the analytical results for the returned archival water samples and evaluates their compliance with ISS water quality standards. The WAFAL also received and analyzed aliquots of some Russian potable water samples collected in-flight and pre-flight samples of Rodnik potable water delivered to the Station on the Russian Progress vehicle during Expeditions 21 to 25. These additional analytical results are also reported and discussed in this paper.