Development and Performance of the Oxygen Sensor in the CSA-CP Aboard the International Space Station

A combustion products analyzer (CPA) was built for use on the Shuttle in response to several thermodegradation incidents during early flights. When the Toxicology Laboratory at Johnson Space Center (JSC) began to assess the air quality monitoring needs for the International Space Station (ISS), the CPA was the starting point for the design of a thermodegradation event monitor. The final product was significantly different from the CPA and was named the “compound specific analyzer-combustion products” (CSA-CP). One major change from the CPA was the replacement of the hydrogen fluoride sensor with an oxygen sensor. The focus of this paper will be the CSA-CP oxygen sensor’s ground testing, performance on ISS, and reduced pressure testing in response to a need on ISS.