METHOD FOR CONTINUOUSLY MONITORING VERY SMALL AMOUNT OF OXYGEN AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a monitor system capable of inexpensively and certainly detecting a very small amount of oxygen getting mixed in carrier gas in a ppb order. SOLUTION: The sampling gas branched from and led out of a high purity inert gas supply passage is continuously supplied to an oxygen sensor utilizing a zirconia sintered material to detect the oxygen gas in the high purity inert gas flowing through the high purity inert gas supply passage. The detection signal from the oxygen sensor is inputted to an amplifying part to continuously monitor the concentration of the oxygen gas in the high purity inert gas flowing through the high purity inert gas supply passage in a ppb order.