The increasing frequency of International Space Station (ISS) egress operations results in chemical contamination of the spacecraft environment. Among the most important contaminants are propellant residues (such as hydrazine) and their decomposition by-products, as well as coolants such as ammonia and Freon. Ammonia has a 24 hour Spacecraft Maximum Allowable Concentration (SMAC) of 7 ppm (Perry, 2010) and hydrazine has a 24 hour SMAC of 0.3 ppm (NASA/JSC 20584, March, 2001). These highly alkaline chemicals rapidly penetrate skin and coagulate proteins. Furthermore, a hydrazine fuel leak onto any hot surfaces may cause fire. TDA Research Inc. proposes to develop a new adsorbent that can remove these contaminants to sub ppmv concentrations. In the Phase I, we will develop the adsorbent media and design a cartridge that will be incorporated into a first response crew mask. We will demonstrate the efficacy of the cartridge in removing these contaminants at full-scale in an environmental chamber (TRL 4). We will also complete the detailed design of a general purpose first response mask, including additional adsorbents and ambient temperature oxidation catalyst that will provide complete protection against all contaminants (in addition to NH3 and hydrazine, CO, volatile organic compounds and combustion by-products, such as sulfur oxides will all be removed). In Phase II, we will work with Gentex, a leading supplier of personal protection systems in fabricating the mask and cartridges. We will complete high fidelity demonstrations in an environmental chamber to fully demonstrate its capability (non-human testing at TRL 6).
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