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The ability of iodine to maintain microbial water quality in a simulated spacecraft water system is being studied. An iodine level of about 2.0 mg/L is maintained by passing ultrapure influent water through an iodinated ion exchange resin. Six liters are withdrawn daily and the chemical and microbial quality of the water is monitored regularly. Stainless steel coupons used to monitor biofilm formation are being analyzed by culture methods, epifluorescence microscopy, and scanning electron microscopy. Results from the first two years of operation show a single episode of high bacterial colony counts in the iodinated system. This growth was apparently controlled by replacing the iodinated ion exchange resin. Scanning electron microscopy indicates that the iodine has limited but not completely eliminated the formation of biofilm during the first two years of operation.

Microbial proliferation in the STS potable water system is prevented by maintaining a 2-5 ppm iodine residual. The iodine is added to fuel cell water by an iodinated ion exchange resin in the Microbial Check Valve (MCV). Crew comments indicated excessive iodine in the potable water. To better define the problem, a method of in-flight iodine analysis was developed. Inflight analysis during STS-30 and STS-28 indicated iodine residuals were generally in the 9-13 ppm range. It was determined that the high iodine residual was caused by MCV influent temperatures in excess of 120 °F. This is well above the MCV operating range of 65-90 °F. The solution to this problem was to develop a resin suitable for the higher temperatures. Since 8 months were required to formulate a MCV resin suitable for the higher temperatures, a temporary solution was necessary. Two additional MCV's were installed on the chilled and ambient water lines leading into the galley to remove the excess iodine.

The crew of the Space Station wiii divide their time between caring for the station systems and operating and maintaining payloads. Because of the relatively non-stressful flight regime, the long duration program life, and advances in automation and robotics they can devote more work time to payloads than in previous manned programs.

Recovery of oxygen (O2) from water will be needed on future long-duration manned space missions. Direct electrolysis of cabin water vapor into O2 and hydrogen (H2) offers the advantage of avoiding the phase change, separation and handling of liquid water in zero gravity. These considerations affect liquid electrolysis subsystems which are presently baselined for central O2 generation aboard the Space Station. This paper presents the results of a technology development program that Life Systems, Inc., in cooperation with the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) has been undertaking. The goal of the program is to develop Water Vapor Electrolysis (WVE) hardware that can selectively be used as localized topping capability in areas of high metabolic activity without oversizing the central Air Revitalization System (ARS).

CUPOLA: /'KYUP∂L∂ 1. a: a rounded vault raised on a circular or other base and forming a roof or a ceiling- compare dome: b: a small structure built on top of a roof to provide interior lighting, to serve as a lookout… During the past 24 months, the concept of a space station cupola evolved from a small, bubble-type viewport into the primary location for proximity operations requiring direct, unobstructed viewing. Derived from a viewing analysis conducted by the Man-Systems Division at the Johnson Space Center, the cupola represents a solution for out-of-plane viewing which can not be provided by windows placed in the shell of the habitation and/or laboratory modules. An extended Man-Systems design study resulted in several cupola configurations, each illustrating an alternate solution to the required balance between viewing, projected space station operations and human/machine interface issues.

Humidity control is essential in the extravehicular mobility unit (EMU). Excessive humidity can lead to visor fogging; accumulation of water, which can block air flow through the vent loop and corrode system components; and uncomfortable conditions for the person inside the EMU, reducing productivity. This paper describes the development of a membrane-based process for dehumidifying the EMU. The membrane process promises to be smaller, lighter, and more energy efficient than the other technologies being considered for dehumidification, and it requires no expendables. The system employs novel dehydration membranes, which were tested for 90 days at conditions expected to be present in the EMU. The results of these tests indicate that membrane-based technology can effectively control humidity in the EMU.

The Environmental Health System (EHS) and Health Maintenance Facility (HMF) on Space Station Freedom will require a comprehensive microbiology capability. This requirement entails the development of an automated system to perform microbial identifications on isolates from a variety of environmental and clinical sources and, when required, to perform antimicrobial sensitivity testing. The unit currently undergoing development and testing is the Automated Microbiology System II (AMS II) built by Vitek Systems, Inc. The AMS II has successfully completed 12 months of laboratory testing and evaluation for compatibility with microgravity operation. The AMS II is a promising technology for use on Space Station Freedom.

The NASA Lyndon B. Johnson Space Center (JSC) Life Sciences Space Station Program (LSSSP) will support the NASA goal of expanding human presence beyond the Earth into the solar system. The Biomedical Research Project (BmRP) is a major element of the LSSSP and is planning an onboard laboratory for studying the effects of microgravity on humans. During the Space Station era, the major emphasis for the BmRP is to identify and quantify the effects of reduced gravitational forces on humans and, if necessary, to develop methods and techniques which counteract or modify these effects to promote man's long-term health and productivity while working in space and upon return to Earth. A status of current science, technical, and programmatic planning activities that are being conducted at JSC to define BmRP requirements for the Space Station Program is presented herein.