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Trace chemical contaminants produced by equipment offgassing and human metabolic processes are removed from the atmosphere of the International Space Station's U.S. Segment by a trace contaminant control subassembly (TCCS). The TCCS employs a combination of physical adsorption, thermal catalytic oxidation, and chemical adsorption processes to accomplish its task. A large bed of granular activated charcoal is a primary component of the TCCS. The charcoal contained in this bed, known as the charcoal bed assembly (CBA), is expendable and must be replaced periodically. Pre-flight engineering analyses based upon TCCS performance testing results established a service life estimate of 1 year. After nearly 1 year of cumulative in-flight operations, the first CBA was returned for refurbishment. Charcoal samples were collected and analyzed for loading to determine the best estimate for the CBA's service life.

A new water recovery system designed towards fulfillment of NASA's Vision for Space Exploration is presented. This water recovery system is an evolution of the current state-of-the-art system. Through novel integration of proven technologies for air and water purification, this system promises to elevate existing technology to higher levels of optimization. The novel aspect of the system is twofold: Volatile organic contaminants will be removed from the cabin air via catalytic oxidation in the vapor phase, prior to their absorption into the aqueous phase, and vapor compression distillation technology will be used to process the condensate and hygiene waste streams in addition to the urine waste stream. Oxidation kinetics dictate that removal of volatile organic contaminants from the vapor phase is more efficient.

Contaminated air and process gases, whether in a crewed spacecraft cabin atmosphere, the working volume of a microgravity science or ground-based laboratory experiment facility, or the exhaust from an automobile, are pervasive problems that ultimately effect human health, performance, and well-being. The need for highly-effective, economical decontamination processes spans a wide range of terrestrial and space flight applications. Adsorption processes are used widely for process gas decontamination. Most industrial packed bed adsorption processes use activated carbon because it is cheap and highly effective. Once saturated, however, the adsorbent is a concentrated source of contaminants. Industrial applications either dump or regenerate the activated carbon. Regeneration may be accomplished in-situ or at an off-site location. In either case, concentrated contaminated waste streams must be handled appropriately to minimize environmental impact.

The International Space Station (ISS) Internal Active Thermal Control System (IATCS) uses a water based heat transport fluid with specific chemical parameters and additives for corrosion and microbial control. The fluid and hardware have experienced anomalies since activation of the United States Laboratory (USL), including chemical and possibly, microbial corrosion. The required sampling of the fluid has the crewmembers removing samples via an in-line sampling tool to perform real-time trace ammonia contamination tests using color change strips, and filling a 150 ml bag from each loop for the ground laboratory analyses. The former activity requires stable storage of the strips, and for the latter activity, it is highly desirable to return the ground sample as stable as possible. This paper describes the process for materials selection, test methods/set-up, results, and final recommendation for a replacement outer bag.

NASA is initiating a space human factors research and technology development program in October 1982. The impetus for this program stems from: the frequent and economical access to space provided by the Shuttle, the advances in control and display hardware/software made possible through the recent explosion in microelectronics technology, heightened interest in a space station, heightened interest by the military in space operations, and the fact that the technology for long duration stay times for man in space has received relatively little attention since the Apollo and Skylab missions. The rationale for and issues in the five thrusts of the new program are described. The main thrusts are: basic methodology, crew station design, ground control/operations, teleoperations and extra vehicular activity.

THE LOW-POWER SPACE NUCLEAR ROCKET conceived by NASA engineers is described in this paper. It is compared with the chemical rocket and the nuclear turboelectric ion propulsion system. In developing the concept for this low-power rocket, NASA engineers concentrated on attaining low weight and high hydrogen temperature, and on solving problems concerned with automatic control and operation of high-temperature reactors. It was presumed that the NASA 1.5 million-lb thrust engine would be available, and could place 25,000 lb in orbit, at the time the nuclear rocket is ready for test. As experience is gained reactors of higher power can be developed. These can, perhaps, be used as second stages of larger chemical boosters. Finally, high-power, high-temperature rockets for booster application can be undertaken.

There was a thermal anomaly of the landsat-7 Enhanced Thematic Mapper Plus (ETM+) radiative cooler cold stage during the cooler outgas phase in flight. With the cooler door in the outgas position and the outgas heaters enabled, the cold stage temperature increased to a maximum of 323 K when the spacecraft was in the sunlight, which was warmer than the 316.3 K upper set point of the outgas heater controller on the cold stage. Also, the outgas heater cycled off when the cold stage was warming up to 323 K. A corrective action was taken before the attitude of the spacecraft was changed during the first week in flight. One orbit before the attitude was changed, the outgas heaters were disabled to cool off the cold stage. The cold stage temperature increase was strongly dependent on the spacecraft roll and yaw. It provided evidence that direct solar radiation entered the gap between the cooler door and cooler shroud.

The trace contaminant control system (TCCS) located in the International Space Station's (ISS) U.S. laboratory module employs physical adsorption, thermal catalytic oxidation, and chemical adsorption to remove trace chemical contamination produced by equipment offgassing and anthropogenic sources from the cabin atmosphere. The chemical adsorption stage, consisting of a packed bed of granular lithium hydroxide (LiOH), is located after the thermal catalytic oxidation stage and is designed to remove acid gas byproducts that may be formed in the upstream oxidation stage. While in service on board the ISS, the LiOH bed exhibited a change in flow resistance that leading to flow control difficulties in the TCCS. Post flight evaluation revealed LiOH granule size attrition among other changes. An experimental program was employed to investigate mechanisms hypothesized to contribute to the change in the packed bed's flow resistance.