Laser remote analysis for decommissioning of Fukushima Daiichi Nuclear Power Station (FDNPS) and its application for radioactive sampled materials

若井田 育夫  ; 大場 弘則  ; 中西 隆造; 赤岡 克昭 ; 柴田 卓弥  ; 狩野 貴宏 

Wakaida, Ikuo; Oba, Hironori; Nakanishi, Ryuzo; Akaoka, Katsuaki; Shibata, Takuya; Karino, Takahiro

Remote analysis by optical fiber base Laser Break down Spectroscopy (LIBS) has been developed and successfully performed under a radiation of 10kGy/h and total dose more than MGy. A simple pollution protection unit with a cleaned air ventilation system has been installed to the previously developed portable optical fiber LIBS system, and also the Remote controlled XYZ Sample Stage for LIBS Probe has been combined for the challenge at the actual working site in FDNPS where air contamination will be undeniable. The dose rate of the working environment was about 10Sv/h, and the maximum surface dose rate of the sample was about 20mSv/h. The ablation fumes induced by laser irradiation has a high potential to make a internal exposure when they are mixed with human breath air. The special filtering system based on the medical surgical smoke removal technology has been constructed and succeeded to remove the ablation fumes.