Annals of the ICRP最新文献

Medical disaster response training is provided for international students in Kawauchi Village to share the lessons learnt from the accident at Fukushima Daiichi nuclear power plant. At present, this is difficult due to the coronavirus disease 2019 (COVID-19) pandemic. The purpose of this article is to report the development of hands-on medical training software on a topic that does not require in-person attendance. The 'Kawauchi Legends' disaster simulator was developed as a useful tool to teach the medical response to various disasters, and this was applied in a 3-day webinar in October 2020. Fourteen students participated in the webinar and successfully learnt medical management, manipulating their avatars in the virtual environment. This software can be an effective substitute for in-person disaster training without physical involvement. Such innovative teaching methods mean that lessons from the Fukushima accident can continue to be shared, even in the COVID-19 pandemic situation.

After the accident at Fukushima Daiichi nuclear power plant on 11 March 2011, radioactive materials were released into the atmosphere resulting in environmental contamination. Following the implementation of environmental decontamination efforts, the Radiation Dose Registration Centre of the Radiation Effects Association established the radiation dose registration system for decontamination and related workers to consolidate and prevent the loss of radiation records. This article presents statistics on the radiation doses of decontamination and related workers using official records. Since approximately 10 years have passed since the accident in Fukushima, the types of work conducted in the affected restricted areas have changed over time. Therefore, changes in radiation dose for each type of work and comparisons with nuclear workers are presented.

This paper does not necessarily reflect the views of the International Commission on Radiological Protection.Several radiation monitoring research projects are underway on dose assessment, biological analysis, and risk communication under an agreement with Namie Town. Indoor radon and thoron progeny concentrations have been measured using passive-type monitors to estimate internal doses due to inhalation. In addition, airborne radiocaesium concentrations at five points in Namie Town have been analysed using a high-purity germanium detector to estimate internal doses for comparison with radon. External radiation doses from natural and artificial radionuclides have also been estimated using an in-situ gamma-ray spectrometer. Other support activities are mentioned briefly in this article.

This paper does not necessarily reflect the views of the International Commission on Radiological Protection.Since the accident at Fukushima Daiichi nuclear power station in March 2011, Japan Atomic Energy Agency (JAEA) has been contributing actively to the environmental recovery of Fukushima and the decommissioning of Fukushima Daiichi nuclear power station from a technical aspect, through a wide range of research and development (R&D) activities including fundamental research and applicational technology development. JAEA has been conducting R&D such as the characterisation of fuel debris, and treatment and disposal of radioactive wastes based on the 'Mid-and-Long-Term Roadmap' authorised by the Japanese Government. This R&D is mainly promoted by Collaborative Laboratories for Advanced Decommissioning Science (CLADS) in Tomioka Town, and CLADS has also been promoting cooperation with domestic and foreign research institutes, related companies, universities, etc. In addition, Naraha Centre for Remote Control Technology Development in Naraha Town commenced full operation in April 2016 for the development and demonstration of remote control technologies planned for use in the decommissioning of Fukushima Daiichi nuclear power station and disaster response. Okuma Analysis and Research Centre in Okuma Town is under construction for the analysis and characterisation of fuel debris and various radioactive wastes. Ten years have passed since the Great East Japan Earthquake and the accident at Fukushima Daiichi nuclear power station, and environmental conditions in Fukushima have been improving. The evacuation zone has been lifted, and preparation of specific recovery areas in the difficult-to-return zone has progressed. However, the reconstruction of Fukushima and the decommissioning of Fukushima Daiichi nuclear power station are still in progress, and JAEA will continue its R&D for the decommissioning of Fukushima Daiichi nuclear power station with domestic and international expertise in order to further contribute to the reconstruction of Fukushima.

This paper does not necessarily reflect the views of the International Commission on Radiological Protection.This article analyses the communication experiences of radiation protection experts at federal/regional and local level. Efforts to justify protective measures were more successful at federal level, while the task of adjusting risk perception among local residents remains unresolved. At the recovery stage (15 years after the accident at Chernobyl nuclear power plant), the main difficulties were associated with the fact that expert knowledge was in conflict with public perception of the risk of low doses and legislative approaches. In these situations, communication success depends directly on an expert's personality. When large areas are affected, the efforts of a few dedicated experts are clearly not sufficient. More systematic approaches (training of doctors, teachers, etc.) require governmental support and experienced personnel. Federal authorities had changed their attitudes by the 15th anniversary of the accident. However, at regional level, this process stretched out for another 15 years. Public perception of large-scale health consequences still persists. Examples and survey results are presented in this article.

The importance of involving experts in the development of strategies for managing areas contaminated as a result of a nuclear accident is now well recognised. Following the Chernobyl accident in 1986, the initial focus, quite understandably, was on the technical aspects of reducing doses to the affected population. Subsequently, work carried out in the UK and elsewhere in Europe looked at the broader impacts of protective actions on agriculture, the environment, and society. From 1997, a group of experts from academia, government, and non-government organisations met regularly in the UK to debate these issues. One of the outputs included the first version of the UK Recovery Handbook for Radiation Incidents in 2005. Based on the success of the UK group, a European network of experts was established, leading to the development of European handbooks in 2009. The UK handbooks are living documents that are updated regularly with substantive input from experts.

It has been nearly 10 years since the accident at Fukushima Daiichi nuclear power plant. With the cooperation of those involved, the site, which was once in a crisis situation, has improved to the point where it is possible to look ahead and proceed with work on schedule. In the off-site area, conditions for returning home have been progressed, and evacuation orders for some areas have been lifted by the Japanese Government. This article describes, in respect of the various efforts being made on site at the moment, the current status of fuel removal from the spent fuel pools, preparations for fuel debris retrieval, improvement of the working environment, and future plans. Removal of fuel from the spent fuel pool for Unit 4 was completed in December 2014, and work is continuing with Unit 3 in order to complete by March 2021. The decision was made to install a large cover in advance for Unit 1 in consideration of the risk of dust scattering, and to conduct fuel removal for Unit 2 from the south side without dismantling the existing upper section of the building. The target is for fuel removal from the pools, including Units 5 and 6, to be complete by 2031. Regarding fuel debris retrieval, progress in various investigations has made it possible to grasp the distribution of debris in the reactor containment vessels of Units 1-3 to a certain extent, and it was decided that the first retrieval will start with the most-investigated unit (Unit 2). A robot arm will be used for retrieval; initially, a trial retrieval will be started, and once the retrieval method has been verified and confirmed, the scale of retrieval will be expanded in stages using a device with the same mechanism. The working environment of Fukushima Daiichi nuclear power plant has also improved. By reducing the stirring up of radioactive materials due to facing (paving), etc., it became possible to reduce the degree of protective clothing needed, and the area in which people can work with simple clothing such as general work clothes now represents 96% of the entire site. Due to various reduction measures, the effective dose of workers is currently approximately 0.2-0.4 mSv month^-1 on average per person. The work environment will continue to be improved steadily in the future. Finally, I would like to briefly mention the direction of future decommissioning efforts. The decommissioning of Fukushima Daiichi nuclear power plant and contaminated water management are being implemented based on the national Mid-and-Long-Term Roadmap. The latest edition (5th revision) sets out the milestones until 2031, and we are on target to achieve the goals set forth here and the goals set forth in the Nuclear Regulatory Commission's risk map. To that end, the Mid-and-Long-Term Decommissioning Action Plan 2020, which shows the main work processes of the decommissioning, was announced. This will enable us to proceed with decommissioning work more systematically in the future while looking a

Since the International Research Institute for Nuclear Decommissioning (IRID) was established as a technology research association in August 2013, it has been engaged in research and development (R&D) for decommissioning the Fukushima Daiichi nuclear power plant, which is currently an urgent issue, to strengthen the platform for decommissioning technology for the future. The work of IRID R&D is classified into three main pillars: removal of spent nuclear fuel from the pool; retrieval of fuel debris; and technological development for treatment and disposal of solid radioactive waste. This article describes an overview of R&D as of the first half of the fiscal year 2020, mainly focusing on investigation inside primary containment vessels and retrieval of fuel debris.