The Zero Air Generator is a low-cost, handheld source of zero air (air that has been scrubbed of CO2 and water vapor) to be used for zeroing infrared gas analyzers (IRGAs). The 31022 consists of a small pump and a molecular sieve. The pump is powered by 2 AA batteries. A “Test” port located on the 31022 can be used to determine when to replace the molecular sieve.