Humidity Condensate Sampling System for Shuttle, Mir and International Space Station

Archival sampling of potable water and condensate for ground laboratory analysis has been an important part of the Shuttle-Mir program because of coolant leaks and other events on Mir that have affected water quality. We report here the development of and preliminary results from a novel device for single phase humidity condensate collection at system pressures. The sampler consists of a commercial-off-the-shelf Teflon^® bladder and a custom reinforced Nomex^® restraint that is sized properly to absorb the stress of applied pressures. A plastic Luer-Lock disconnect, with poppet actuated by a mating Luer-Lock fitting, prevents the contents from being spilled during transport. In principle, a sampler of any volume can be designed. The empty mass of the reusable one-liter sampler is only 63 grams. Several designs were pressure tested and found to withstand more than 3 atmospheres well in excess of typical spacecraft water or wastewater system pressures. The vessel's ability to be hard-filled permits unattended sample collection. These devices, with appropriate interfacing hardware, have been used to collect water samples from Russian portable water tanks (Mir 23) and directly from the condensate recovery system (Mir 24). Shuttle condensate was collected using this hardware on STS-89 as part of an International Space Station (ISS) Risk Mitigation Experiment, and will be repeated on STS-91. Potential uses of the sampler on ISS are discussed.