A Miniaturized Carbon Dioxide Detector

NOAA supports over 25,000 underwater dive programs per year. To increase the duration and depth of these dives, the use of closed circuit mixed gas rebreathers (CCRs) is being considered. As there currently are no sensors to detect CO2 levels in the breathing gas, Giner, Inc. proposes to continue development of an electrochemical CO2 sensor for CCR use. The technical innovation is the use of a reversible CO2 sensing electrode in a solid-ploymer electrolyte configuration. The overall objective of the proposed Phase II program is to continue development of a miniaturized, novel, solid state, inexpensive thick-film electrochemical sensor that can selectively and accurately detect CO2 over the range 0.5 to 5% surface equivalent to quantify CO2 levels in a closed circuit mixed gas rebreather. The program goal is to fabricate and deliver a complete sensor system that will detect both O2 and CO2 in the recirculated gas stream. The CO2 sensor will accurately monitor up to 5% CO2 in real time. Our approach to develop the proposed CO2 sensor will be to the continued development of a unique sensing electrode that is specific to CO2.