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A room-temperature reactor packed with hydrophobic catalysts for the oxidation of hydrogen isotopes released in a nuclear facility will contribute to nuclear safety. The inorganic-based hydrophobic Pt catalyst named H1P has been developed especially for efficient oxidation over a wide concentration range of hydrogen isotopes at room temperature, even in the presence of saturated water vapor. The overall reaction rate constant for hydrogen oxidation with the H1P catalyst in a flow-through system using a tritium tracer was determined as a function of space velocity, hydrogen concentration in carriers, temperature of the catalyst, and water vapor concentration in carriers. The overall reaction rate constant for the H1P catalyst in the range near room temperature was considerably larger than that for the traditionally applied Pt/ Al 2 O 3 catalyst. Moreover, the decrease in reaction rate for H1P in the presence of saturated water vapor was slight compared with the reaction rate in the absence of water vapor due to the excellent hydrophobic performance of H1P. Oxidation reaction on the catalyst surface is the rate-controlling step in the range near room temperature and the rate-controlling step is shifted to diffusion in a catalyst substratum above 313 K due to its fine porosity. The overall reaction rate constant in the range near room temperature was dependent on the space velocity and hydrogen concentration in carriers. The overall reaction rate constants in the range of 1;000=T greater than 3.2 correlated to k overall ½s À1 ¼ 5:59 Â 10 7 Â SV½h À1 Â exp À 67:7 ½kJ/mol R g T ;where the space velocity range was from 600 to 7,200 h À1 .

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In order to improve the safe handling and control of tritium for ITER fuel cycle, effective "in-situ" tritium accounting methods have been developed at Tritium Process Laboratory in Japan Atomic Energy Research Institute under one of the ITER-EDA R&D Tasks. A remote and multi-location analysis of process gases by an application of laser Raman spectroscopy developed and tested could provide a measurement of hydrogen isotope gases with a detection limit of 0.3 kPa for 120 seconds analytical periods. An "in-situ" tritium inventory measurement by application of a "self assaying" storage bed with 25 g tritium capacity could provide a measurement with a required detection limit less than 1 % and a design proof of a bed with 100 g tritium capacity.