Monitoring technique within the nuclear facilities

Present state of recent techniques on tritium monitoring in the operation environment of the facilities is introduced. The tritium monitoring in the air is mainly described, and surface pollution and water monitoring are also mentioned. All of the present tritium monitoring methods are based on measurement of radiation. In measurement of massive tritium, physical measurement such as weight measurement, laser-Raman method and others are also used. For monitoring, some other methods using absorption spectra of laser light and micro wave are also in research but are not in actual use. At present, surface pollution monitoring with tritium is mainly conducted by Smear method or super thin film large area gas flow counter method. And, for waste water monitoring, an automatic liquid scintillator method was developed owing to reduction of limit of nuclear concentration. (G.K.)