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The availability of real time, automated, and reliable atmosphere and water monitoring instrumentation within the timeframe of future manned lunar and Mars missions is vital to the success of the Space Exploration Initiative (SEI). For these missions, with durations measured in years, the environmental control and life support system (ECLSS) must be properly instrumented to assure the crew that the physical, chemical, and biological properties of the atmosphere and water are within ranges that are healthy and safe. The technology for measuring some properties, such as temperature and pressure, is currently available for most applications; however, there are a number of instrumentation functions required for future long duration missions that cannot be performed by current technology. Defining the areas where current instrumentation technology falls short of satisfying potential SEI requirements is a task of immediate importance.

As part of the Sustaining Engineering program for the International Space Station (ISS), a ground simulator of the Internal Thermal Control System (ITCS) in the Lab Module was designed and built at the Marshall Space Flight Center (MSFC). To predict ITCS performance and address flight issues, this facility is operationally and functionally similar to the flight system and flight-like components were used when available. Flight software algorithms, implemented using the LabVIEW® programming language, were used for monitoring performance and controlling operation. Validation testing of the low temperature loop was completed prior to activation of the Lab module in 2001. Assembly of the moderate temperature loop was completed in 2002 and it was validated in 2003. Even before complete validation the facility was used to address flight issues, successfully demonstrating the ability to add silver biocide and to adjust the pH of the coolant.

Operation of the Internal Thermal Control System (ITCS) Cold Plate/Fluid-Stability Test Facility commenced on September 5, 2000. The facility was intended to provide advance indication of potential problems on board the International Space Station (ISS) and was designed: To be materially similar to the flight ITCS. To allow for monitoring during operation. To run continuously for three years. During the first two years of operation the conditions of the coolant and components were remarkably stable. During this same period of time, the conditions of the ISS ITCS significantly diverged from the desired state. Due to this divergence, the test facility has not been providing information useful for predicting the flight ITCS condition. Results of the first two years are compared with flight conditions over the same time period, showing the similarities and divergences.

The Portable Fire Extinguisher (PFE) is used to displace oxygen and cool a closed volume to prevent/eliminate a fire hazard on the International Space Station (ISS). An analysis and test was performed on the discharge characteristics of the PFE system on a payload rack volume. Analytical data was developed to support the test data and determine the real versus ideal gas state of the carbon dioxide (CO2) during discharge into the rack. This paper presents the analytical and test data for PFE discharge to determine applicability of this system to rack and open volume fires with respect to mass discharged, local area concentration, temperature, and displacement volume. Ancillary to this analysis is a consideration of the local open volume carbon dioxide concentration and the probable impact on the crew and atmosphere revitalization and supply system for ISS. This report will include testing data recently performed at Marshall Space Flight Center (MSFC).