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This paper presents the requirements and baseline design for a subsurface Life Support System (LSS) to support an underground habitat. The purpose of this effort was to demonstrate/validate the feasibility of building an operational habitat to support survivable and enduring operations of a deeply based ICBM weapon system. Described is an overall life support design for a crew of 100 to 600 persons that encompasses all required life support subsystems, arrangement and construction of Habitat enclosures and protection from the effects of a subsurface environment. Effects of habitat layout, type of power source, environment, rock temperature and moisture content, crew size and mission length were investigated. Regenerative and non-regenerative systems were compared on the basis of life cycle cost. Results of this Life Support System study were much different than those previously conducted for space and submarine application due to the difficulty in rejecting heat.

The Space Station Temperature and Humidity Control Condensing Heat Exchangers will be utilized to remove and collect atmospheric water vapor generated by the metabolic and hygienic activity of crew members. The porous hydrophilic coating within the heat exchangers will be continually moist and in contact with a steady flow of cabin air which makes them susceptible to microbial growth. This paper summarizes the findings from an ongoing study to evaluate biofilm formation characteristics and microbial control techniques for the Space Station Condensing Heat Exchangers (CHX). This ongoing study examines whether the CHX's are susceptible to performance degrading microbial colonization with microbial challenge testing under simulated system environmental conditions. Furthermore, the three candidate microbial control approaches of periodic heating, periodic drying and incorporation of an antimicrobial agent, into the hydrophilic coating are evaluated.

The original Shuttle Extravehicular Mobility Unit (EMU) Hard Upper Torso (HUT) configuration developed in1978 by Hamilton Standard and ILC, Dover had the arm attached in such a way that the shoulder bearing outer race was integral with the HUT. This method of attachment has been termed “planar arm.” During development, this configuration proved unacceptable because some astronauts and test subjects experienced difficulty, and in some cases pain, while donning. Interference occurred when the arms transitioned from vertical to horizontal as the HUT was entered (arms over head). At the time, designers needed to quickly resolve this issue and certify the EMU for the first Shuttle flight. The solution - pivot sockets - allowed the shoulder bearing to pivot relative to the HUT for donning purposes and then pivot back to allow for optimum arm performance. The pivoted HUT configuration has been very successful and is one of the design features that allows arm mobility and range in the EMU.

The Space Station Temperature and Humidity Control Condensing Heat Exchangers will be utilized to collect and remove atmospheric water vapor generated by the metabolic and hygienic activity of crew members. The porous hydrophilic coating within the heat exchangers will always be wet. Cabin air will continuously flow through the heat exchangers during system operation which makes them a potential site for microbial colonization. This paper summarizes the findings from an ongoing study which evaluates biofilm formation on wet hydrophilic coated panels compared to panels to which microbial control measures have been applied. The control measures evaluated are an antimicrobial agent within the coating and periodic drying.

The Shuttle Orbiter Design Test Objective (DTO) test effort of the Extended Duration Orbiter (EDO) Urinal Subassembly and the EDO Waste Collector Subsystem (WCS) has been conducted on STS–52 and STS–54 flights respectively. The objective of these DTO test flights was to prove out the new waste collection concepts and hardware including convenient and safe in–flight servicing, human factor enhancements, natural biodegradation, and hardware configuration. Actual DTO testing included real time zero gravity collection of liquid and solid human waste as well as special on–board set–ups for performance evaluation of the commode. The results of the hardware operation on these Orbiter flights along with post flight test evaluation are contained and discussed in this report. Any improvements resulting from this evaluation can be considered for use on the similar Space Station Waste Management Design.

The design of an oxygen generation system for advanced submarine life support is presented. Future designs will be driven by cost effectiveness as well as the ability to perform critical mission requirements. This paper reviews the advances in oxygen generating equipment and discusses the approach taken to reduce life support system cost without performance or reliability degradation. The performance of a high differential pressure electrolysis cell design is discussed. The impact of a domeless electrolyzer module on ship life support system complexity and cost is presented.

The Shuttle Extravehicular Mobility Unit (EMU) is an integral component in successful satellite salvaging operations. FMU evolution to its current operational status has occurred through implementation of carefully analyzed and thoroughly tested changes. The net result of these changes is known as the Block II FMU. This paper discusses the basic FMU system requirements, the philosophy used in the design of the Block I EMU, and the operation of the Life Support System (LSS); outlines the evolution of the Block II configuration; and briefly discusses future progression of the LSS. The Block II LSS configuration has improved serviceability between flights, simplified user operation, improved performance, decreased maintenance (by extending component life), and, most importantly, improved mean time between failures by a factor of fourteen.