DEVELOPMENT OF A CARBON DIOXIDE PARTIAL PRESSURE SENSOR

The objective of the program was to design and develop a compact airborne CO2 sensor unit capable of sensing and measuring the CO2 content of manned, sealed environments. A prototype carbon dioxide sensor was designed, built, and calibrated. The sensor operates by alternately comparing the infrared absorption of the air sample at 4.26 microns, where CO2 exhibits strong absorption and at 3.90 microns where it has little absorption. A two color rotating filter provides sampling 200 times per second. The unit weighs 10 pounds and has a power consumption of 70 watts. The instrument is capable of detecting a concentration of at least 0.30% CO2 and has full scale capability to 5%. (Author)