\u0531\u0540\u054e \u0561\u0577\u056d\u0561\u057f\u0561\u0576\u0584\u0576\u0565\u0580\u0568 \u0540\u0531\u0537\u053f-\u056b \u0570\u0561\u0574\u0561\u0580 \u057d\u056f\u057d\u057e\u0565\u056c \u0565\u0576 2002 \u0569.-\u056b\u0576, \u0565\u0580\u0562 \u053f\u0565\u0576\u057f\u0580\u0578\u0576\u0568 \u057d\u057f\u0565\u0572\u056e\u0565\u0581 \u054c\u056b\u057d\u056f\u056b \u0563\u0576\u0561\u0570\u0561\u057f\u0574\u0561\u0576 \u056d\u0578\u0582\u0574\u0562\u0568 (\u054c\u0533\u053d), \u0578\u0580\u0576 \u0561\u057c\u0561\u0576\u0581\u0584\u0561\u0575\u056b\u0576 \u0564\u0565\u0580 \u0578\u0582\u0576\u056b \u0540\u0531\u0537\u053f-\u056b \u0531\u0540\u054e \u0561\u0577\u056d\u0561\u057f\u0561\u0576\u0584\u0576\u0565\u0580\u056b \u056b\u0580\u0561\u056f\u0561\u0576\u0561\u0581\u0574\u0561\u0576 \u0574\u0565\u057b: \u053f\u0565\u0576\u057f\u0580\u0578\u0576\u056b \u054c\u0533\u053d-\u056b \u0570\u056b\u0574\u0576\u0561\u056f\u0561\u0576 \u0563\u0578\u0580\u056e\u0561\u057c\u0578\u0582\u0575\u0569\u0576\u0565\u0580\u0568 \u0570\u0565\u057f\u0587\u0575\u0561\u056c\u0576 \u0565\u0576.<\/p>\n
- \n
- \u0531\u0540\u054e \u0574\u0578\u0564\u0565\u056c\u0576\u0565\u0580\u056b \u0574\u0577\u0561\u056f\u0578\u0582\u0574<\/li>\n
- \u0531\u0540\u054e \u0574\u0578\u0564\u0565\u056c\u0576\u0565\u0580\u056b \u056f\u056b\u0580\u0561\u057c\u0578\u0582\u0569\u0575\u0578\u0582\u0576 \u057c\u056b\u057d\u056f-\u057f\u0565\u0572\u0565\u056f\u0561\u0581\u057e\u0561\u056e \u0578\u0580\u0578\u0577\u0578\u0582\u0574\u0576\u0565\u0580\u056b \u056f\u0561\u0575\u0561\u0581\u0574\u0561\u0576 \u0570\u0561\u0574\u0561\u0580,<\/li>\n
- \u0531\u0537\u053f \u057d\u0561\u0580\u0584\u0561\u057e\u0578\u0580\u0578\u0582\u0574\u0576\u0565\u0580\u056b \u0570\u0578\u0582\u057d\u0561\u056c\u056b\u0578\u0582\u0569\u0575\u0561\u0576 \u057a\u0561\u0580\u0561\u0574\u0565\u057f\u0580\u0565\u0580\u056b \u056a\u0561\u0574\u0561\u0576\u0561\u056f\u056b\u0581 \u056f\u0561\u056d\u057e\u0561\u056e \u0583\u0578\u0583\u0578\u056d\u0578\u0582\u0569\u0575\u0561\u0576 \u057e\u0565\u0580\u056c\u0578\u0582\u056e\u0578\u0582\u0569\u0575\u0578\u0582\u0576 (\u00ab\u056e\u0565\u0580\u0561\u0581\u0574\u0561\u0576\u00bb \u0561\u0566\u0564\u0565\u0581\u0578\u0582\u0569\u0575\u0561\u0576 \u0563\u0576\u0561\u0570\u0561\u057f\u0578\u0582\u0574),<\/li>\n
- \u0574\u056b\u057b\u0578\u0582\u056f\u0561\u0575\u056b\u0576 \u0561\u0576\u057e\u057f\u0561\u0576\u0563\u0578\u0582\u0569\u0575\u0561\u0576 \u0578\u056c\u0578\u0580\u057f\u0578\u0582\u0574 \u0561\u0566\u0563\u0561\u0575\u056b\u0576 \u056f\u0561\u0580\u0563\u0561\u057e\u0578\u0580\u0578\u0572 \u057a\u0561\u0570\u0561\u0576\u057b\u0576\u0565\u0580\u056b \u0576\u0561\u056d\u0561\u0563\u056e\u0565\u0580\u056b \u0574\u0577\u0561\u056f\u0578\u0582\u0574,<\/li>\n
- \u0531\u0540\u054e-\u056b \u057e\u0565\u0580\u0561\u0562\u0565\u0580\u0575\u0561\u056c \u0578\u0582\u057d\u0578\u0582\u0574\u0576\u0561\u056f\u0561\u0576 \u0564\u0561\u057d\u0568\u0576\u0569\u0561\u0581\u0576\u0565\u0580\u056b \u056b\u0580\u0561\u056f\u0561\u0576\u0561\u0581\u0578\u0582\u0574,<\/li>\n
- \u0570\u0561\u0574\u0561\u0563\u0578\u0580\u056e\u0561\u056f\u0581\u0578\u0582\u0569\u0575\u0578\u0582\u0576 \u0531\u0540\u054e \u0562\u0576\u0561\u0563\u0561\u057e\u0561\u057c\u056b \u0570\u0565\u0572\u056b\u0576\u0561\u056f\u0561\u057e\u0578\u0580 \u056f\u0561\u0566\u0574\u0561\u056f\u0565\u0580\u057a\u0578\u0582\u0569\u0575\u0578\u0582\u0576\u0576\u0565\u0580\u056b \u0570\u0565\u057f:<\/li>\n<\/ul>\n
PSA Model Development<\/h3>\n
\u054c\u0533\u053d-\u0576 \u0561\u056f\u057f\u056b\u057e\u0578\u0580\u0565\u0576 \u0574\u0561\u057d\u0576\u0561\u056f\u0581\u0565\u056c \u0567 \u0540\u0531\u0537\u053f-\u056b 2-\u0580\u0564 \u0567\u0576\u0565\u0580\u0563\u0561\u0562\u056c\u0578\u056f\u056b \u0570\u0561\u0574\u0561\u0580 \u0531\u0540\u054e \u0574\u0578\u0564\u0565\u056c\u0576\u0565\u0580\u056b \u0574\u0577\u0561\u056f\u0574\u0561\u0576 \u0563\u0578\u0580\u056e\u0568\u0576\u0569\u0561\u0581\u056b\u0576, \u0574\u0561\u057d\u0576\u0561\u057e\u0578\u0580\u0561\u057a\u0565\u057d, \u056d\u0574\u0562\u056b \u0574\u0561\u057d\u0576\u0561\u0563\u0565\u057f\u0576\u0565\u0580\u0568 \u0574\u0561\u057d\u0576\u0561\u056f\u0581\u0565\u056c \u0565\u0576 \u0531\u0540\u054e \u0570\u0565\u057f\u0587\u0575\u0561\u056c \u0570\u0561\u057f\u057e\u0561\u056e\u0576\u0565\u0580\u056b \u0574\u0577\u0561\u056f\u0574\u0561\u0576\u0568.<\/p>\n
- \n
- \u0576\u0565\u0580\u0584\u056b\u0576 \u057d\u056f\u0566\u0562\u0576\u0561\u056f\u0561\u0576 \u0561\u0566\u0564\u0561\u056f\u0576\u0565\u0580,<\/li>\n
- \u0576\u0565\u0580\u0584\u056b\u0576 \u0570\u0580\u0564\u0565\u0570\u0576\u0565\u0580,<\/li>\n
- \u0561\u0580\u057f\u0561\u0584\u056b\u0576 \u057e\u057f\u0561\u0576\u0563\u0576\u0565\u0580 (\u0562\u0561\u0581\u0561\u057c\u0578\u0582\u0569\u0575\u0561\u0574\u0562 \u057d\u0565\u0575\u057d\u0574\u056b\u056f \u057e\u057f\u0561\u0576\u0563\u0568):<\/li>\n<\/ul>\n
\n![\"shahen-1\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-1.jpg\")
\nRisk profile for ANPP Unit 2<\/i><\/p>\n
\n![\"shahen-3\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-3.jpg\")
\nTraining course on NPP fire safety visiting worms (Biblis NPP, Germany)<\/i><\/p>\n
\n\u0531\u0576\u057e\u057f\u0561\u0576\u0563\u0578\u0582\u0569\u0575\u0561\u0576 \u0570\u0561\u057e\u0561\u0576\u0561\u056f\u0561\u0576\u0561\u0575\u056b\u0576 \u057e\u0565\u0580\u056c\u0578\u0582\u056e\u0578\u0582\u0569\u0575\u0561\u0576 \u0577\u0580\u057b\u0561\u0576\u0561\u056f\u0578\u0582\u0574 \u056f\u0561\u057f\u0561\u0580\u057e\u0578\u0582\u0574 \u0567 \u0576\u0561\u0587 \u0570\u0561\u056f\u0561\u0570\u0580\u0564\u0565\u0570\u0561\u0575\u056b\u0576 \u057a\u0561\u0577\u057f\u057a\u0561\u0576\u0578\u0582\u0569\u0575\u0561\u0576 \u0563\u0576\u0561\u0570\u0561\u057f\u0578\u0582\u0574:<\/p>\n
Special attention is paid to the development of the RAG\u2019s capabilities in the field of fire simulation and fire impact analyses. Currently the NRSC works with two computer codes devoted to fire simulation – CFAST and SYLVIA. CFAST code is used extensively for the fire PSA analysis, whereas the SYLVIA code is currently used for modeling of ventilation systems for critical compartments, as well as for the CFAST results\u2019 verification.<\/p>\n
\n![\"shahen-2\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-2.jpg\")
\nCFAST model of ANPP Unit 2 boron unit<\/i><\/p>\n
\nIn the field of fire modeling, the professionalism of our employees are developed through local and international trainings, workshops, real analytical practices, investigation of experimental results and other relevant activities.<\/p>\n
PSA Model Application and Risk-Informed Decision Making<\/h3>\n
The PSA models are periodically applied for investigation of specific problems and decision making. The application of plant-specific PSA includes:<\/p>\n
- \n
- modernization activities\u2019 prioritization,<\/li>\n
- PTS investigation (selection of accident scenarios),<\/li>\n
- justification of the allowable outage times in the technical specifications, and<\/li>\n
- justification of the symptom-based emergency operating procedures (selection of bounding scenarios).<\/li>\n<\/ul>\n
\n![\"shahen-4\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-4.jpg\")
\nEvent tree constructed for selection of critical accident scenarios potentially leading to PTS<\/i><\/p>\n
\nCurrently, the RAG is in the process of PSA application for the maintenance effectiveness monitoring. From this perspective the PSA is mainly used for the development of indicators and probabilistic criteria for maintenance effectiveness evaluation. In addition, jointly with the ANPP and the IAEA, the NRSC works on the PSA\u2019s application that is meant to identify the combinations of external hazards which are critical for the ANPP. This analysis is performed by the fault sequence analysis\u2019s approach developed and promoted by the IAEA.<\/p>\n
Time-Dependent Reliability Analysis (ageing PSA)<\/h3>\n
According to the PRIS database, most operating reactors have been used for more than 20 years, consequently, the ageing problem gradually becomes more critical. The time-dependence of reliability, on the other hand, is not fully reflected in the current PSA models. Therefore, the NRSC has initiated activities aimed at incorporating ageing in the PSA. In 2006, jointly with the ISTC (project A-1492) and Ageing PSA European Network (EC JRC IET, IRSN, INR, NRI REZ, LEI, and others), the NRSC launched this research project. The purpose of the research is to predict the risk profile behavior in time so that to make the PSA-based decision making process more comprehensive. During this research the NRSC\u2019s achievements were the following:<\/p>\n
- \n
- collection of wide range statistical data for the VVER-440 safety related equipment;<\/li>\n
- implementation of ageing trend analysis for selected components;<\/li>\n
- incorporation of analysis\u2019 results in the ANPP PSA model and the development of ageing PSA models which allow to estimate the risk profile evolution for more than 15 years;<\/li>\n
- application of the ageing PSA models for risk-informed decision making (feasibility studies were done for risk-informed systems\u2019 ranking and modernization prioritization);<\/li>\n
- performance of reliability prediction for safety related pipe segments at the ANPP (by WinPRAISE code).<\/li>\n<\/ul>\n
\n![\"shahen-9\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-9.jpg\")
\nIncreasing trend evaluation for switcher’s failure rate parameter<\/i><\/p>\n
\nResearch activities are done in close co-operation with Ageing PSA European Network members such are EC JRC IET (Netherlands), IRSN (France), INR (Romania), NRI REZ (Czech Republic), LEI (Lithuania), and others. Together with the APSA Network, the NRSC actively got involved in the review of the PSA topical guidelines and implementation of case studies aimed at verifying the applicability of the ageing PSA, namely:<\/p>\n
- \n
- review of the qualitative approach for systems\u2019 selection, structures and components for the Ageing PSA (EUR23446EN<\/a>);<\/li>\n
- review of the guidelines for the analysis of data which relates to the NPP\u2019s components\u2019 and systems\u2019 ageing (EUR23954EN<\/a>);<\/li>\n
- case study of the ANPP\u2019s Unit 2 for the APSA component selection;<\/li>\n
- data analysis related to the VVER-440 equipment\u2019s ag\u0435ing (EUR24643EN<\/a>);<\/li>\n
- feasibility study on the applicability of risk-informed decision process of the results that are obtained by using the ageing PSA model (EUR26606EN<\/a>).<\/li>\n<\/ul>\n
\n![\"shahen-5\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-5.jpg\")
\nNRSC was involved in the EC JRC publications related PSA topical guidelines and implementation of case studies<\/i><\/p>\n
\nDevelopment of National Regulations in the field of Nuclear Safety<\/h3>\n
In the development of national regulations the RAG is involved in the following fields:<\/p>\n
- \n
- requirements of the PSA,<\/li>\n
- regulatory review guide on the PSA,<\/li>\n
- requirements to the format and content of safety assessment report,<\/li>\n
- requirements of reactor\u2019s site evaluation,<\/li>\n
- requirements of the plant lifetime extension,<\/li>\n
- requirements of the maintenance effectiveness evaluation,<\/li>\n
- modification implementation procedure, and<\/li>\n
- requirements of design safety.<\/li>\n<\/ul>\n
In terms of the national regulation development, the RAG mainly works on the development of probabilistic criteria, on the identification of requirements for systems\u2019 reliability evaluation and performance monitoring, on the development of external and internal hazards\u2019 analysis\u2019 principles, and on other tasks.<\/p>\n
PSA Training<\/h3>\n
The RAG also provides trainings to the NRSC\u2019 newcomers, the Armenian Nuclear Regulatory Authority\u2019s staff, and to university students in the field of probabilistic safety assessment and risk-informed decision making. Moreover, the RAG specialists often receives invitations to take part in international trainings as lecturers. PSA trainings usually cover the following courses (modules):<\/p>\n
- \n
- Module 1 (the NPP safety and technology)<\/li>\n<\/ul>\n
This section provides the basic information on nuclear safety concepts (safety functions, safety principles, safety assessment, and accidents categorization), and basic information on the NPP technology (plant design, safety features, and plant response logic).<\/p>\n
- \n
- Module 2 (the introduction to the PSA)<\/li>\n<\/ul>\n
This section provides detailed training on the PSA\u2019s methodology, as well as a brief overview of the PSA\u2019s applications and risk-informed decision making. The PSA methodology training covers all main elements of the PSA (PSA scope, initiating event analysis, accident sequence analysis, system analysis, human reliability analysis, data analysis, and CCF modeling), and the implementation of practical examples for specific PSA tasks. In addition, the 2nd module provides brief information on possible uses of the PSA models, risk-informed decision making principles, and available regulations in this field.<\/p>\n
- \n
- Module 3 (the advanced PSA information)<\/li>\n<\/ul>\n
This section covers the investigation of the PSA\u2019s specific topics and the familiarization with PSA related codes. Particularly, the trainees deeply investigate the aspects related to the PSA applications and risk-informed decision making, time-dependent reliability modeling, incorporation of ageing aspects in the PSA, fire simulations, and others. The trainees also become familiar with appropriate computer codes such as Risk Spectrum, CFAST, WinBUGS, and others.<\/p>\n
NRSC participated in the ANRA staff\u2019s two-stage special PSA training, namely:<\/p>\n
- \n
- Stage 1 (project AR\/RA\/03, 2006-2008) \u2013 a basic training course on the PSA provided by the NRSC, AVN and GRS.<\/li>\n
- Stage 2 (project AR\/RA\/04, 2008-2010) \u2013 a training on the PSA regulatory review and risk-informed decision making provided by NRSC, STUK and UJD.<\/li>\n<\/ul>\n
International Cooperation<\/h3>\n
In the PSA field, the RAG is deeply involved in several international activities and topical projects such as working group activities, missions, and trainings. The main international activities are described below.<\/p>\n
The VVER Regulatory Forum PSA Working Group<\/h3>\n
To examine the use of the PSA in countries that have the VVER-440 NPPs in operation, the VVER Regulatory Forum established the PSA Working Group (WG) in 2002 (http:\/\/wwerforum.org\/index.php\/en\/current-working-groups\/probabilistic-safety-assessment<\/a>). The WG\u2019s aim is to summarize the regulatory use and practices of the PSA, and to compare the PSA\u2019s attributes. In the PSA WG activities the following countries have been involved: Armenia, Bulgaria, Czech Republic, Finland, Hungary, Russia, Slovakia, Ukraine and India. IAEA and GRS have a role of observers in PSA WG. Since the PSA WG\u2019s first mandate in 2005, the RAG has been participating in these events. During this period, the RAG took on the following tasks:<\/p>\n
- Module 3 (the advanced PSA information)<\/li>\n<\/ul>\n
- Module 2 (the introduction to the PSA)<\/li>\n<\/ul>\n
- Module 1 (the NPP safety and technology)<\/li>\n<\/ul>\n
- review of the guidelines for the analysis of data which relates to the NPP\u2019s components\u2019 and systems\u2019 ageing (EUR23954EN<\/a>);<\/li>\n
- review of the qualitative approach for systems\u2019 selection, structures and components for the Ageing PSA (EUR23446EN<\/a>);<\/li>\n
![\"shahen-6\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-6.jpg\")
![\"shahen-7\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-7.jpg\")
![\"shahen-8\"](\"http:\/\/nrsc-am.com\/wp-content\/uploads\/2016\/10\/Shahen-8.jpg\")