Safety assessments probabilistic

Insights gained from probabilistic safety assessments (PSAs) should be considered in the design, with the goal of ensuring that no particular feature makes a disproportionately large or uncertain contribution to the overall risk. Detailed information on PSAs can be found in Refs [17-20]. 

The objective of the review of the PSA is to determine to what extent the existing PSA remains valid as a representative model of the plant when the following aspects have been taken into account changes in the design and operation of the plant new technical information current methods and new operational data. 

PSA is a comprehensive and structural approach to identify weaknesses in the design and operation of the plant and to evaluate and compare potential options for remedying any such weaknesses [6,13-16]. The weaknesses (e.g. the 

The PSA should be kept sufficiently up to date during the plant lifetime to make it useful for the decision making process. 

The accident management programme for beyond design basis accidents should be reviewed. It should be determined whether the programme is suitable to prevent severe core damage or to mitigate its consequences [4,17]. 

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PRA - probabilistic risk assessment/probabilistic safety assessment, synonymous with PSA. The PRA Procedures Guide is NUREG/CR-23(X). PRA was the original term but became probabilistic safety assessment to avoid the negative implication of risk. ... 

WA.SH-1400 - The report of the Rasmussen Study that effectively started the use of probabilistic safety assessment. 

AECL, 1989, CANDU-3 Conceptual Probabilistic Safety Assessment. ... 

Allen, P. J. et al., 1990, Summary of CANDU-6 Probabilistic Safety Assessment Study Results, Nuclear Safety 31, 2, pp 202-214. 

Topical Meeting on Probabilistic Safety Assessment, Cl Beach, FL, pp 747-753, January 26-29. 

Fullwood, R. and W. Shier, 1990, PRA Using Event Tables and the Brookhaven Event Tree Analyzer (BETA), The Role and Use of Personal Computers in Probabilistic Safety Assessment and Decision Making, Elsevier, NY, ISBN 1-85166-501-3, pp 79-92/... 

IAEA, 1988, Component Reliability Data for Use in Probabilistic Safety Assessment, lecDoc-478, Vienna. 

Jaitly, R K., 1995, The CANDU-9 Probabilistic Safety Assessment Program, PSA 95, Seoul, Korea, pp 33-38, November 26-30. 

Probabilistic Safety Assessment in the Chemical and Nuclear Industries... 

The last three decades have seen the development of a new science to help us better understand the risk of events about which there is often very little information. The reason there is interest in such a science is that there are a great many societal benefits from activities that involve risk risk that if properly managed through better understanding can greatly benefit the quality of all life on the planet earth, both plant and animal. That science is quantitative risk assessment, also known by such names as probabilistic risk assessment and probabilistic salety assessment, the latter being the preferred name for this text. Probabilistic safety assessment divides the risk question into three questions "What can go wrong " "How likely is it " and "What are the consequences "... 

Probabilistic safety assessment has had its greatest push in relation to the assessment ni risk associated with nuclear power plant operation as documented in the author s previous hook This new book, besides updating and reorganizing the nuclear portions of the previous text, entures into I he salety as.sessment of chemical facilities, another important industry dri ver of probabilistic s.ifety assessment methods and applications. 

This book, for the most part, is a stand-alone text. It addresses not only the fundamentals of PSA as a science, but insights on the regulatory framework affecting its development and apidication. In particular, it provides the basic methods of analysis that can be employed, available databases, an excellent set of examples, software resources, chapter summaries that tacilitate comprehension, and problem sets that are very well connected to the theory. While much has been written about probabilistic safety assessment over the last three decades, this is the most comprehensive attempt so far to provide a much needed college level textbook for the education of risk and safety professionals. It also provides a valuable reference for any individual curious enough about the risk and safety sciences to want to become much more informed. 

Bellamy, L. J., Kirwan, B., Cox, R. A. (1986). Incorporating Human Reliability into Probabilistic Safety Assessment. 5th International Symposium on Loss Prevention and Safety Promotion in the Process Industries, Cannes, France. Paris Societe de Chimie Industrielle. 

For this type of mitigation system, probabilistic safety assessment (PSA) can be used as a tool for evaluation of and feedback to designs. Originally developed on the basis of mles and standards of engineering, resulting in a design enriched by statistical aspects and which meets acceptable risk levels for a plant in normal operation. 

Fullwood, Ralph R. (2000), Probabilistic Safety Assessment in the Chemical and Nuclear Industries, Butterworth Heinemann, New York, USA. 

The probabilistic safety assessment (PSA) for the steam reforming process was carried out to investigate the cause of an accident on combustible gas leak and a conceptual design on a countermeasure against explosion was carried out aiming at reducing the probability ofthe combustible gas leak less than 10-6/year. The rupture of combustible gas pipes is considered as the cause of the leakage. 

A system built with the SPINLINE 3 technologies is a combination of several units, which perform functions following strict safety performances. The achievement of these safety performances is obtained by following a development methodology, which includes the design of the architecture, the validation of probabilistic safety assessment, the qualification of the design with accuracy and response time. 

Probabilistic Safety Assessment and Management, vol. 4, November 27 - December 1, 2000, Osaka, Japan, pp.2383-2388. 

A number of events at nuclear power plants (NPP), as well as results from probabilistic safety assessment (PSA) studies for NPPs, have indicated that events occurring during shutdown modes may contribute significantly to the overall risk associated with NPP operation. 

The 23 participants, representing 14 Member States, reviewed recent developments and discussed directions for future efforts in the area of safety analysis of nuclear power plants during low power and shutdown (LPS) conditions. During the meeting, 18 technical papers were presented, devoted to various aspects of LPS conditions probabilistic safety assessment studies, description of particular phenomena, calculational analysis of individual events, contents of safety reports, hardware modifications, experience from plant operations, etc. 

Rouvroye, J. L. Goble, W. M. Brombacher, A. C. Spiker, R. Th. E., "A comparison study of qualitative and quantitative analysis techniques for the assessment of safety in industry," Proceedings of PSAM III, International Conference on Probabilistic Safety Assessment and Management, Crete, Greece, 1996. 

Hauptmanns U, Jablonski D (2006) Comparison of the availability of trip systems for reactors with exothermal reactions. In Stamatelatos MG, Blackman HS (eds) Proceedings of the 8th international conference on probabilistic safety assessment and management PSAM 8, New Orleans/USA—14-18. May 2006, American Society of Mechanical Engineers, U.S. 

A systematic approach to evaluation should be taken to establish which maintenance tasks are to be performed, on which SSCs, and at what intervals, in order to optimize the use of resources allocated for maintenance and to ensure the availability of the plant. This approach can be used in establishing a preventive maintenance programme and for optimization of the ongoing maintenance programme. The aim of optimization is to use condition monitoring to determine where unnecessary maintenance work and failures induced by errors in maintenance can be avoided. If a probabilistic safety assessment has been performed, its results may be used for this purpose. 

The risk assessment should cover in particular those activities that have a significant influence on the level of risks at the plant, for example, mid-loop operation of a pressurized water reactor. Use should be made of the results of probabilistic safety assessments for the shutdown mode if these are available. Any specific training needs, special procedures for the shutdown mode or additional operating procedures or surveillance necessary should be identified in the risk assessment. 

IAEA (1996) Procedures for conducting probabilistic safety assessments of nuclear power plants (Level 3) , Safety series 50-P-12. 

IAEA (1993) Probabilistic safety assessment for seismic events, TECDOC-724, Vieima. 

AR108 Review of probabilistic safety assessments by regulatory bodies. No. 25, 12 December 2002. AR109 Communication planning by the nuclear regulatory body. No. 24, 20 August 2002. 

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