We have established a procedure for comprehensive safety assessment of aging plant using a combination of two indices; risk index and resilience index. And, we have identified important equipment using a simple resilience index and have extracted failure mode using a risk index with detailed plant model. Those were applied to three loop PWR plant as trials. We are reporting its summary and considering the effectiveness of the resilience index. ...
英字タイトル:
Development of Comprehensive Safety Assessment Method for Aging Nuclear Power Plant Using Risk Index and Resilience Index

Abstract The total system design on Nuclear Plant ensures “Nuclear safety” with making practically achievable efforts to prevent and mitigate nuclear and radiological accidents. The performance based system design with “Defence in depth (D-I-D)” has been laid out as the key means in “preventing accidents”, “controlling escalation to serious consequences”, and “mitigating impact to the public”. D-I-D is extended to the management of severe accidents, and is an approach intended to provide protection a...
英字タイトル:
Development of Resilience Evaluation Method for Nuclear Power Plant (Part4: Concept of System Safety on Operating Nuclear Power Plants)

In order to grasp efficiency of risk information, we tried to apply an insight of PRA to considering of severe accidents; TMI, Chernobyl, and Fukushima Dai-ichi. Based on this analysis, three points are disclosed. At first, PRA can product adequate countermeasures for low-likelihood events; huge earthquake or Tsunami. Next, PRA can prove weak points in design or operation reasonably. Third point is safety culture. PRA and safety culture are seemed to be connected deeply. These analyses revealed PRA is on...
英字タイトル:
-For Discussions with the Public for the Safety of Nuclear Power -Applying Risk Information to Prevention/Mitigation of SA-

Target of PRA is not calculating PRA to get CDF/CFF, but providing significant and useful information from PRA results for risk-informed activities. Lot of risk applications have been implemented these about 20 years in US. After Fukushima Dai-ichi accidents, Japanese Nuclear Regulation Authority provided new regulatory requirements about external events and beyond design events. And Risk Application faces full-scale implementation. In this report, several methods of risk application are showed with adeq...
英字タイトル:
- For Discussions with the Public for the Safety of Nuclear Power -Various Patterns of Risk Application Method and Examples-

After Fukushima daiichi nuclear accident, it becomes more important risk communication with the public. In discussions with the public in nuclear safety, communication and discussions on risks that not only nuclear risks also social risks are important. Differences in viewpoints, understanding, and thought about risks become communication difficult. We need to discuss risks fairly, appropriately with the public and reduce total social risks. ...
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For Discussions with the Public for the Safety of Nuclear Power -Discussion with the Public -

In considering nuclear safety, it is an important task to clarify the relationship with peace of mind that is the heart of people. What is the state that scientific safety is something that people feel safe. We considered the relationship between quantified risk and safety, and ways to acquire peace of mind. We analyzed the thresholds of safety risks as a social common sense, showed a safe condition, and showed the importance of forming a consensus to obtain peace of mind. ...
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For Discussions with the Public for the Safety of Nuclear Power -Safety and Secure-

1.はじめに 社会においては、リスクの理解は様々である。リスク をどのように理解していけば良いのかを示し、リスクについての社会との向き合い方をまとめる。個人のリスク の受け入れは個人で行うものであるが、 社会のリスクは、社会としていかなるリスクを許容するかという仕組みを社会で構築する必要がある。そのためにも、社会リスクとはどんなものであり、どのように社会また個人は、それにどう向き合い、受け入れるリスクの選択をどう行うべきかを述べる。また、原子力リスクの考え方とそれを 一般公衆に対する防災の観点からどのよう......
英字タイトル:
For Discussions with the Public for the Safety of Nuclear Power -Social risk and Nuclear risk -

1.はじめに リスクとは、判断を支援する指標である。したがって、 何を判断しようとするかによって、何がリスクかは異な ってくる。原子力システムの安全に関するリスクといっ ても、安全に対するどのような影響を判断しようとして いるかによって、検討すべきリスクは異なってくる。 また、リスクとは、影響を与えるものと与えられるも のの相互作用である。そのために、原子力システムに関 するリスクを検討する際には、影響を与える原子力シス テムに関する知見と、影響を受ける社会に関する知見が 必要となってくる。さらには、原子......
英字タイトル:
For Discussions with the Public for the Safety of Nuclear Power -Risks for judgments-

The total system design on Nuclear Plant ensures “Nuclear safety” with making practically achievable efforts to prevent and mitigate nuclear and radiological accidents. The performance based system design with “Defence in depth (D-I-D)” has been laid out as the key means in “preventing accidents”, “controlling escalation to serious consequences”, and “preventing harmful consequences to the public”. D-I-D is extended to the management of severe accidents, and is an approach intended to provide protectio...
英字タイトル:
Concept of System Safety on Operating Nuclear Power Plant