Detection of Xenon Exceeding Normal Concentrations at the CTBT Radionuclide Monitoring Station in Takasaki

April 23, 2013

    1. At the Takasaki monitoring station, one of the Comprehensive Nuclear-Test-Ban Treaty Organization他のサイトヘ (CTBTO)’s radionuclide monitoring posts, concentrations of the radioactive noble gas xenon (Xe-131m and Xe-133) exceeding the normal range of variation were detected from samples collected between April 8 and 9.
    2. Referring to this finding, the CTBTO Provisional Technical Secretariat on April 23 announced that the CTBTO’s radionuclide monitoring network had detected radioactive noble gases that could be attributed to the nuclear test announced by the DPRK on February 12.
    3. On the website of the Center for the Promotion of Disarmament and Non-Proliferation他のサイトヘ (commissioned by the Ministry of Foreign Affairs), which serves as the secretariat for domestic implementation of the CTBT, radionuclide measurements taken at the Takasaki station have been publically available since the Great East Japan Earthquake of March 11, 2011. Detailed data pertaining to the measurements in this case are also available on the Center’s website.
    4. CTBT monitoring posts detect extremely small amounts of noble gases with highly sensitive equipment for the purpose of detecting nuclear tests. The radioactive noble gas concentration detected in this case was not at a level that would adversely impact health.
    For further reference
    Availability of Takasaki monitoring station radionuclide measurements
     
    Takasaki monitoring station measurements of radionuclide particulates are made available monthly. Measurements of radionuclide noble gases are posted when they exceed the normal range of variation.