Reference Material: Radiation Exposure Data for Nuclear Industry Workers (FY2020)
By Kataoka Ryohei (CNIC)
CNIC compiled the data below based on the reports from nuclear facility operators contained in the Nuclear Regulation Authority of Japan’s (NRA) “Radiation Management Report” published annually.
Until FY2019, the minimum effective dose measurement was set at “5 mSv or less” and increased in 5 mSv increments, but the regulations for reporting effective dose measurements were revised on April 1, 2020 so that the minimum value of dose categories is “0.1 mSv or less,” and categories of “over 0.1 mSv and up to 1 mSv,” “over 1 mSv and up to 2 mSv,” and “over 2 mSv and up to 5 mSv” have been added. With the detailed setting of low-dose categories, it is now possible to obtain more detailed information on radiation doses.
Looking at the data for FY2020 on reactor facilities for power generation, the radiation doses at the Fukushima Daiichi Nuclear Power Station are almost the same as the previous year. Other than that, the total radiation dose and the maximum dose at Onagawa and the maximum dose at Hamaoka were higher. Doses at Ohi, Takahama, Ikata, Genkai, and Sendai, which were operating in the last fiscal year, are relatively high. The total radiation dose and the maximum radiation dose at Fugen were also higher, but this may be due to the progress in decommissioning. Overall, the total radiation dose and the maximum radiation dose both decreased slightly from the previous year.
Information from 2019 (in Japanese) is available at the websites below:
- Nuclear power plants: www.nsr.go.jp/disclosure/law_new/power_plants/index.html
- Nuclear fuel and other facilities: www.nsr.go.jp/disclosure/law_new/nuclear_facilities/index.html