HYDROGEN DETECTING SYSTEM

PURPOSE:To obtain a hydrogen detecting system at a low cost, which can accurately detect the leakage quantity of hydrogen, by measuring the quantity of the moisture generated from the hydrogen component leaked from a device for treating hydrogen inside thereof (fuel cell or the like). CONSTITUTION:In the case where hydrogen is leaked from a fuel cell 1, hydrogen and the purged inert gas exist in a container 3. Such a gas inside of the container 3 is discharged outside through a pipeline. At this stage, a part of the gas is taken to the branch passage 4 side by a suction pump 5, and mixed with the air by an ejector 6, and supplied to a hydrogen reaction unit 7. In the hydrogen reaction unit 7, hydrogen in the mixture gas is burned with the catalyst so as to form the water. The gas, of which hydrogen component is converted to the water in the reaction unit 7, is supplied to a hydrometer 8 by the sucking force of the pump 5. The hydrometer 8 measures humidity of the supplied gas. Since the quantity of hydrogen is detected on the basis of the moisture quantity, hydrogen can be detected at a low cost without using an expensive hydrogen gas sensor for measuring the quantity of hydrogen on the basis of the heat to be used for burning the hydrogen.