Fiber Optic Chemical Sensors for Manned Space Missions

Two critical sets of variables that must be monitored in life support systems for extended manned space exploration missions are: oxygen and trace gas concentrations in crew air supply and “respiratory” gasses (e.g. O₂ and H₂O vapor) in hydroponic or other regenerative food and oxygen producing units. This paper describes new results in the development of fiber optic sensors targeted at precisely these applications. In particular, we present new data on the performance (sensitivity, accuracy, and precision) of a moisture-insensitive oxygen optrode based on a fluorescent indicator immobilized in a permeable polymer, on a novel fiber optic humidity sensor, and on a miniature nitrogen dioxide optrode.