Development of guidelines on radiation protection for the lens of the eye in Japan

Yokoyama, Sumi*; Iwai, Satoshi*; Tsujimura, Norio; Hashimoto, Makoto; Yoshitomi, Hiroshi; Kato, Masahiro*; Kurosawa, Tadahiro*; Tatsuzaki, Hideo*; Sekiguchi, Hiroshi*; Koguchi, Yasuhiro*; et al.

Proceedings of 15th International Congress of the International Radiation Protection Association (IRPA-15) (Internet), 8 Pages, 2022/00

https://irpa.net/irpa15/T3.1-O0124.pdf

Development of safety design guideline of structures, systems and components of Generation-IV Sodium-cooled Fast Reactor

Okano, Yasushi

Nihon Genshiryoku Gakkai-Shi ATOMO, 60(12), p.764 - 769, 2018/12

JAEA has developed the second safety design guidelines report, "Safety Design Guidelines on Structures, Systems and Components" for Generation-IV SFR system, following the previously published SFR Safety Design Criteria and the first SFR Safety Design Guidelines report and with the reviews by a technical committee under Atomic Energy Society of Japan. This article explains about 14 key points on reactor core system, coolant system, and containment system and also current consistency of international SFR designs to the safety design guidelines.

Guideline on a structural integrity assessment for reactor pressure vessel based on probabilistic fracture mechanics (Contract research)

Katsuyama, Jinya; Osakabe, Kazuya*; Uno, Shumpei; Li, Y.

JAEA-Research 2016-022, 40 Pages, 2017/02

JAEA-Research-2016-022.pdf:4.04MB

For reactor pressure vessels (RPVs) in the light water reactors, the fracture toughness decreases due to the neutron irradiation embrittlement with operating years. In Japan, to prevent RPVs from a nil-ductile fracture, deterministic fracture mechanics methods in accordance with the codes provided by the Japan Electric Association are performed for assessing the structural integrity of RPVs under the pressurized thermal shock (PTS) events by taking the neutron irradiation embrittlement into account. On the other hand, in recent years, probabilistic methodologies for PTS evaluation are introduced into regulations in Europe and the United States. For example, in the United States, a PTS screening criterion related to the reference temperature derived by the probabilistic method is stipulated. If the screening criterion is not satisfied, it is approved to perform the evaluation based on the probabilistic method by calculating numerical index such as through-wall crack frequency (TWCF). To reach the objectives that persons who have knowledge on the fracture mechanics can carry out the PFM analyses and obtain TWCF for a domestic RPVs by referring to this report, we develop the guideline on a structural integrity assessment method based on PFM by reflecting the latest knowledge and expertise.

JSFR design progress related to development of safety design criteria for generation IV sodium-cooled fast reactors, 1; Overview

Kamide, Hideki; Ando, Masato*; Ito, Takaya*

Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 7 Pages, 2015/05

JAEA, JAPC and MFBR have been conducted design study for the Japan Sodium-cooled Fast Reactor (JSFR), which is a design concept aiming at future commercial use as sustainable electric power source. Since 2011, in order to contribute to the development of safety design criteria (SDC) and safety design guideline (SDG), which include the lesson learned from the TEPCO's Fukushima Dai-ichi Nuclear Power Plants accident, in the frame work of generation IV international forum (GIF), the design study is focusing on the design measures against sever external events such as earthquake and tsunami. At the same time, the design study is going into detail and paying much attention to the maintenance and repair to make surer its feasibility. This paper summarizes the design concept of the demonstration version of JSFR in which progress of design work was incorporated.

Review report; Safety and reliability issues on digital instrumentation and control systems in nuclear power plants and United States nuclear regulatory commission's dispositions

Watanabe, Norio; Suzudo, Tomoaki

JAERI-Review 98-013, 78 Pages, 1998/09

JAERI-Review-98-013.pdf:5.87MB

no abstracts in English

Studies on the safety design guidelines of Generation-IV Sodium-cooled Fast Reactors, 4; Studies on event selection process and set of design conditions based on objective provision tree methodology

Kubota, Ryuzaburo*; Tani, Akihiro*; Shimakawa, Yoshio*; Kubo, Shigenobu; Okano, Yasushi

no journal, , 

The objective Provision Tree (OPT) methodology was applied for Generation-IV Sodium-cooled Fast Reactor system to analyses challenges and mechanisms for core damage prevention and containment function maintain and to clarify sets of design conditions. The OPT results were utilized to select the list of importance events of JSFR as an example.

Establishment of guideline for credibility assessment of nuclear simulations

Tanaka, Masaaki

no journal, , 

Guideline for Credibility Assessment of Nuclear Simulations has been established and issued by the Atomic Energy Society of Japan (AESJ) through the discussion at the Simulation Reliability Assessment Subcommittee in the Advanced and Fundamental Systems Technical Committee (ATC), the ATC and the Standards Committee (SC). This guideline specifies the fundamental concept on the assessment of simulation credibility in the nuclear system. When the guideline is to be issued, recent status of the activities for publication of guidelines and standards related to the verification and validation inside and outside the country is introduced.

Outlines of establishment of guideline for credibility assessment of nuclear simulations

Tanaka, Masaaki

no journal, , 

Outline of the Guideline for Credibility Assessment of Nuclear Simulations which has been established and issued by the Atomic Energy Society of Japan (AESJ) through the discussion at the Simulation Reliability Assessment Subcommittee in the Advanced and Fundamental Systems Technical Committee (ATC), the ATC and the Standards Committee (SC), is introduced and recent status of the activities for publication of guidelines and standards related to the verification and validation inside and outside the country is also introduced.

Research Committee Report on Safety Design Guidelines for Generation-IV Sodium-cooled Fast Reactor, 2; Status of international review

Okano, Yasushi

no journal, , 

The Safety Design Criteria Phase I Report had been issued in 2013, and the following feedbacks from US-NRC, France IRSN, IAEA, and China NNSA are being incorporated for the next issue of the report. The international review on the Safety Approach Safety Design Guideline Report was started in 2016, and the interim feedbacks from the IAEA were provided. The important discussion points and technical backgrounds on these feedbacks will be presented at the session.

Review outline of developing guidelines on safety management of radioactive waste bearing natural nuclides

Saito, Tatsuo

no journal, , 

Regarding low-level radioactive waste bearing uranium and NORM, we enumerated the historical developing for safety regulation concerning burial disposal and clearance, by the outline of the public reports for safety case about (1) radon and progeny nuclides, (2) natural nuclides and natural viability, (3) regulatory exemption, regulatory exclusion, clearance. The result of confirmation is as follows. (1) The guidelines for protection from NORM are consistent in our society and the country, and guidelines for intervention in existing radiation situation are applied. (2) In planned exposure, except for uranium clearance, discussion has been postponed on the basic concept of safety assessment concerning final disposal of waste due to handling of natural persistence. (3) With regard to radon, there were guidelines for describing treat with its natural universality partially considered and excluding international clearance standard concentrations below the Fukushima accident from the evaluation subjects, but the others are undecided. (4) In the deliberations on the intermediate depth in the disposal at the regulatory committee, uranium waste is excluded, and the waste in the reactor that can suppress latent exposure to the extent of pit disposal is targeted. (5) Introduction of intervention level is being considered for public exposure caused by human invasion after the management period, considering ultra long-term evaluation.