Suitability of a simple sampler using a brass bar for gaseous tritiated water measurement

• Published in: Fusion engineering and design 2021-11, Vol.172, p.112743, Article 112743
• Main Authors: Nakayama, Masato, Hara, Masanori, Kobayashi, Fumihiko, Oyama, Sachiko, Ota, Masashi, Sakajo, Takaharu, Nakagawa, Hiroo, Kondo, Masato
• Format: Article
• Language: English
• Subjects: Brass bar; Cooling condensation; Liquid nitrogen; Liquid scintillation counter; Oxidation; Scintillation counters; Stainless steels; Tritium; Water measurement; Water vapor; Working conditions; Working environment measurement; Workplaces
• ISSN: 0920-3796; 1873-7196
• DOI: 10.1016/j.fusengdes.2021.112743

A simple sampler using a brass bar and liquid nitrogen for measuring tritium in workplaces was designed, and the suitability of the device was evaluated. The brass bar was arranged to allow its end to touch liquid nitrogen in a stainless-steel bottle, and the water vapor in the air became saturated and condensed on the surface of the brass bar. The condensation was defrosted and the tritium in the defrosted water was analyzed by a liquid scintillation counter. The data obtained with the new sampler were compared with the data obtained with a conventional modified oxidation–liquid collection sampler. The relative ratios of the data obtained with the new sampler to the data obtained with the conventional sampler were 0.64–1.54 (average 0.99, relative standard deviation 23.0%), and the new sampler showed high usefulness in working environment measurement of tritium. The data obtained with the new sampler, as the conventional sampler, showed the seasonal effect and the position dependence in the room. Thus, the applicability of the new sampler for working environment measurement of tritium was confirmed.