WorldWideScience

Sample records for risk-informed in-service inspections

  1. Risk informed In-service Inspection

    International Nuclear Information System (INIS)

    Corak, Z.

    2003-01-01

    insights. It is expected that licensees will ask for modifications of plant's design, operation, and other activities that require NRC approval to incorporate risk insights into their ISI programs. In-service inspection program in which is incorporated risk insights is known as risk-informed in-service inspection programs, RI-ISI. Until the RI-ISI is approved for generic use, the staff expects that licensees will ask for modifications of ISI programs by requesting NRC to approve alternative inspection programs. Alternative inspection programs must meet 10 CFR 50.55a (a)(3)(i) which says that 'the applicant shall demonstrate that the proposed alternatives would provide an acceptable level of quality and safety'. As always, licensees should identify how the chosen approach, methods, data, and criteria are appropriate for the decisions that have to be made. RI-ISI can provide reduction of scope and frequency of inspections that may lead to higher risk. The higher risk means that a probability of failure or consequences are higher and shutdown of nuclear power plants is more likely to occur. RI-ISI can also provide extensive scope of inspection or increased frequency of inspection. (author)

  2. The applications of risk-informed in-service-inspection

    International Nuclear Information System (INIS)

    Ting, K.; Ko, T.-H.; Li, Y.-C.; Wu, W.-F.; Lu, Y.-L.; Chien, F.-T.

    2005-01-01

    The US NRC and nuclear industry encouraged the applications of risk-informed In-Service Inspection (RI-ISI) which can be an alternative program to the ASME Section XI In-service Inspection requirements. The Implementation of RI-ISI can improve the substantial cost as well as does reductions. From the aspect of defense in depth for nuclear safety, the achievements of these procedures can identify the inspection rank to promote the integrity of the current inspection program. Thus, this study utilizes this techniques to implement risk assessment on safety class 1 recirculation piping welds where sensitized to IGSCC of Taibei BWR-6 nuclear power plant. In the evaluation process, WinPraise code is used to calculate the failure probabilities of all welds. The result of risk evaluations can be referred to the further regulatory and plant operation. (authors)

  3. Risk informed in-service inspection and testing in Spain

    International Nuclear Information System (INIS)

    Bros, Juan; Marcelles, Ignacio

    2002-01-01

    The Spanish nuclear regulatory authority, the Consejo de Seguridad Nuclear (CSN), requires the use of codes and standards in force in the country of origin of the plant technology. For this reason, the in-service inspection and testing programs applied at Spanish nuclear power plants basically adhere to the requirements of the ASME XI and ASME OM Codes. It is not surprising that when the earliest developments aimed at drawing up risk informed inservice inspection and testing programs were initiated within the framework of ASME, the Spanish industry should follows such developments very closely. In fact, persons within the Spanish nuclear industry joined different ASME committees involved in the development and approval of the various code cases encompassing these developments. Developments specific to the Spanish nuclear power plants were initiated at a time when the aforementioned reference documentation was in a very advanced stage of development/approval. Two clearly differentiated lines of work got under way: On the one hand, and as regards risk informed in-service testing programs, the American standards were used as the sole reference. In the case of risk informed in-service inspection programs, the Spanish nuclear power plant-owning utilities and the Consejo de Seguridad Nuclear decided to draw up a Spanish guideline that, although using the ASME developments as a reference, would have its own specific characteristics. In relation to the above, and referring to the chronology of the events, the activities performed to date in Spain are described

  4. Risk informed approach to the in-service inspection activities

    International Nuclear Information System (INIS)

    Korosec, D.; Vojvodic Tuma, J.

    2004-01-01

    In the present paper, the aspects of Risk Informed In-Service Inspection (RI-ISI) are discussed. Slovenian Nuclear Safety Administration (SNSA) and its authorized organization for the ISI activities, Institute of Metals and Technologies (IMT), are actually permanently involved in the ISI processes of the nuclear power plant (NPP) Krsko. Based on the previous experience on the ISI activities, evaluation of the results and review of the existing practice in nuclear world, the activities are started to asses the piping of systems in the light of probability of failure. This is so called Risk Informed approach. By the design established criteria, standards and practice gives good fundaments for the improvements implementation. Improvements can be done on the way that the more broad knowledge about safety important components of the systems shall bee added to the basic practice. It is necessary to identify conditions of the safety important components, such as realistic stress and fatigue conditions, material properties changes due aging processes, the temperature cycling effects, existing flaws characterization in the light of the previous detection and equipment technique used, assessment of the measurement accuracy on the results etc. In addition to this deterministic approach, the principles of risk evaluation methods should be used. NPP Krsko has, as practically majority of NPP's, probabilistic risk assessment (PRA) studies for all safety important systems and components. The methods and results from these studies can be efficiently used to upgrade classical deterministic results, based on which the in-service program as a whole is usually done. In addition to the above mentioned, risk assessment and evaluation of the piping shall be done, which is not covered by the existing PRA analysis. To do this it is necessary to made risk evaluation of the piping segments, based on previous structural element probability assessment. Probabilistic risk assessment is important

  5. Increase plant safety and reduce cost by implementing risk-informed in-service inspection programs

    International Nuclear Information System (INIS)

    Billington, A.; Monette, P.

    2001-01-01

    The idea behind the program is that it is possible to 'inspect less, but inspect better'. In other words, the risk-informed In-Service Inspection (ISI) process is used to improve the effectiveness of examination of piping components, i.e. concentrate inspection resources and enhance inspection strategies on high safety significant locations, and reduce inspection requirements on others. The Westinghouse Owners Group (WOG) risk-informed ISI process has already been applied for full scope (Millstone 3, Surry 1) and limited scope (Beznau, Ringhals 4, Asco, Turkey Point 3). By examining the high safety significant piping segments for the different fluid piping systems, the total piping core damage frequency is reduced. In addition, more than 80% of the risk associated with potential pressure boundary failures is addressed with the WOG risk-informed ISI process, while typically less that 50% of this same risk is addressed by the current inspection programs. The risk-informed ISI processes are used to improve the effectiveness of inspecting safety-significant piping components, to reduce inspection requirements on other piping components, to evaluate improvements to plant availability and enhanced safety measures, including reduction of personnel radiation exposure, and to reduce overall Operation and Maintenance (O and M) costs while maintaining regulatory compliance. A description of the process as well as benefits from past projects is presented, since the methodology is applicable for WWER plant design. (author)

  6. Increase plant safety and reduce cost by implementing risk-informed In-Service Inspection programs

    International Nuclear Information System (INIS)

    Billington, A.; Monette, P.; Doumont, C.

    2000-01-01

    The idea behind the program is that it is possible to 'inspect less, but inspect better'. In other words, the risk-informed In-Service Inspection (ISI) process is used to improve the effectiveness of examination of piping components, i.e. concentrate inspection resources and enhance inspection strategies on high safety significant locations, and reduce inspection requirements on others. The Westinghouse Owners Group (WOG) risk-informed ISI process has already been applied for full scope (Millstone 3, Surry 1) and limited scope (Beznau, Ringhals 4, Asco, Turkey Point 3). By examining the high safety significant piping segments for the different fluid piping systems, the total piping core damage frequency is reduced. In addition, more than 80% of the risk associated with potential pressure boundary failures is addressed with the WOG risk-informed ISI process, while typically less than 50% of this same risk is addressed by the current inspection programs. The risk-informed ISI processes are used: to improve the effectiveness of inspecting safety-significant piping components; to reduce inspection requirements on other piping components; to evaluate improvements to plant availability and enhanced safety measures, including reduction of personnel radiation exposure; and to reduce overall Operation and Maintenance (O and M) costs while maintaining regulatory compliance. A description of the process as well as benefits of past projects is presented, since the methodology is applicable for VVER plant design. (author)

  7. A risk-informed approach to optimising in-service inspection of piping

    International Nuclear Information System (INIS)

    Billington, A.; Monette, P.

    1999-01-01

    Traditional criteria for the selection of in-service inspection locations in piping, have come to be regarded as being out-of-touch with current knowledge of piping failures and with current measures of safety importance. An alternative , risk-informed, method has been developed and successfully licensed, that systematically establishes an inspection plan addressing all safety-related piping systems, in a way that is optimized with respect to the safety gain achieved through in-service inspection. The principles of the method are discussed and the results of several applications are summarized, all of which demonstrate that the risk-informed program would lead to significant improvements in the overall level of plant safety, while at the same time re-distributing the inspections in such a way that reduces both plant costs and radiation exposure to personnel.(author)

  8. Risk-informed in-service inspections of nuclear power plants: European activities

    International Nuclear Information System (INIS)

    Simola, K.; Gandossi, L.

    2010-01-01

    Risk-informed in-service inspection (RI-ISI) methods aim at enhancing ISI effectiveness by taking into account the risk importance of possible inspection sites. These methods are widely applied in US, but in Europe the situation is different, as there are many regulatory environments implying a variety of ISI codes and standards and national guidelines. The objective of the European Network for Inspection Qualification, ENIQ, is to co-ordinate and to manage at European level expertise and resources for the qualification of non-destructive inspection techniques and procedures primarily for the in-service inspection of nuclear components. ENIQ has established a Task Group on Risk (TGR) to work towards developing best practice for RI-ISI methodologies. TGR has published a European framework document for risk-informed in-service inspection, and the group has been working at producing more detailed recommended practices and discussion documents on several RI-ISI related issues. In addition, TGR has been active in initiating international projects, such as the JRC-OECD/NEA coordinated RI-ISI benchmark exercise (RISMET). This paper describes the activities and publications of TGR to date, and summarises the contents and main results of the RISMET RI-ISI benchmark exercise. (orig.)

  9. Application of risk-informed methods to in-service piping inspection in Framatome type nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Jin Hoi; Lee, Jeong Seok; Yun, Eun Sub

    2014-01-01

    The Pressurized water reactor owners group (PWROG) developed and applied a risk-informed in-service inspection (RI-ISI) program, as an alternative to the existing ASME Section XI sampling inspection method. The RI-ISI programs enhance overall safety by focusing inspections of piping at high safety significance (HSS) locations where failure mechanisms are likely to be present. Additionally, the RI-ISI program can reduce nondestructive evaluation (NDE) exams, man-rem exposure for inspectors, and inspection time, among other benefits. The RI-ISI method of in-service piping inspection was applied to 3 units (KSNPs: Korea standard nuclear power plants) and is being deployed to the other units. In this paper, the results of RI-ISI for a Framatome type (France CPI) nuclear power plant are presented. It was concluded that application of RI-ISI to the plant could enhance and maintain plant safety, as well as provide the benefits of greater reliability.

  10. RIBA Project - Risk-Informed approach for In-Service Inspection of Nuclear Power Plant Components. Project summary

    International Nuclear Information System (INIS)

    Lidbury, D.; Smith, G.

    2001-12-01

    The need for a European review of a Risk-Informed Approach for In-Service Inspection of Nuclear Power Plant Components (RIBA) was identified in 1998. This was as a priority item in the programme of activities conducted in the framework of the Council Resolutions of 22 July 1975 and of 18 June 1992 on the Technological Problems of Nuclear Safety. The RIBA Project was established in November 1999 as a 24-month Study Contract funded by the European Commission within the frame of the former DG XI WGCS (Working Group on Codes and Standards). The Study Contract was subsequently managed for the EC by DG TREN. The participants in RIBA were Serco Assurance (project coordinator), Ringhals AB, EDF, Tecnatom SA and Westinghouse Electric Europe. The work is presented in a summary report with the detailed results contained in three companion reports as follows: main conclusions and recommendations, Review of Existing Risk-Informed Methodologies, A Comparative Study of Risk-Informed In-Service Inspection Applications, Conclusions and Recommendations for Risk-Informed in-service inspection methodology applied to Nuclear Power Plants in Europe. (author)

  11. Report on the Regulatory Experience of Risk-Informed In-service Inspection of Nuclear Power Plant Components and Common Views (consensus document)

    International Nuclear Information System (INIS)

    2004-08-01

    The present report represents the work product of the activities conducted by the Task Force. The TF performed a review and inventory of the existing approaches to risk-informed inservice inspection and testing, and completed its work in 1999 with a Current Practices Document 2, titled Report on risk-informed in-service inspection and in-service testing (EUR 19153 EN). In November 2001, the NRWG held a Special session on risk-informed applications, with emphasis on risk-informed inservice inspection, where results and experiences from pilot studies on risk-informed inservice inspection (RI-ISI), performed in several European countries, were presented and discussed. As a follow-up in May 2002, the TF was reconvened with the objectives to analyse from the regulatory point of view key aspects associated with the application of risk-informed inservice inspection, and to go beyond a state of the art report, presenting a series of recommendations of good practices or common positions reached by the regulators represented in the Task Force. (author)

  12. Application of risk-informed in-service inspection approach. Pilot study on low pressure emergency core cooling system of NPP Temelin

    International Nuclear Information System (INIS)

    Horacek, L.; Palyza, J.; Zdarek, J.; Vizina, M.

    2004-01-01

    In-service inspection (ISI) programme of piping systems based on Riskinformed In-service Inspections (RI-ISI) approach represents for the WWER NPP licensee first overall systematic conceptual solution of the problems associated with design and design modifications of ISI programme for piping systems. The approach enables to consider possible savings and comparison of in-service inspection programmes according to more objective criteria including those calculated in PSA, in contrast to present much empiric experience collected by manufacturers, operators and ISI vendors in the past. Service experience has shown limited correlation between the deterministic ISI requirements and actual field failures or degradation mechanisms. Where field failures have been observed in piping, they have generally been due to either material concerns (e.g., Intergranular Stress Corrosion Cracking) or stress/cycling mechanisms not identified in the original design basis documents (e.g., thermal stratification), and therefore would not be selected for inspection under current requirements. Risk-informed in-service inspections represent integrated multidisciplinary approach to the in-service inspection programme fulfilling the enhanced requirements of the Czech Regulatory Body (SUJB) for defence in depth concept applied to weld joints of safety related components, application of qualified NDT methods/techniques and introducing of inspections for cause approach. Inspections for cause take into account analysis of both active and potential degradation mechanisms specific to piping system concerned. Simultaneously, this approach enables the licensee to reach, in cases justified from safety point of view, economic savings resulting from lowering of both number and extent of performed in-service inspections and optimisation of their performance. RI ISI pilot study based in majority on EPRI methodology implemented for WWER type reactors has been performed for LP ECCS (Low Pressure Emergency

  13. From PISC to risk informed inspection

    International Nuclear Information System (INIS)

    Crutzen, S.; Lemaitre, P.; Fabbri, L.

    1998-01-01

    In this paper the correlation between inspection effectiveness, inspection qualification and risk informed inspection will be treated in view of harmonisation of inspection of nuclear plant components. Through the different phases of the PISC programme the necessity has been demonstrated to show the effectiveness of the inspection through a formal process of qualification in order to ensure that a certain level of effectiveness has been reached. Inspection qualification is indeed the way to quantify the capability level of inspection techniques used. The targets to be met by the inspection is information which should be obtained from risk based analyses. (author)

  14. Development and testing of VTT approach to risk-informed in-service inspection methodology. Final report of SAFIR INTELI INPUT Project RI-ISI

    International Nuclear Information System (INIS)

    Cronvall, O.; Maennistoe, I.; Simola, K.

    2007-04-01

    This report summarises the results of a research project on risk-informed in-service inspection (RI-ISI) methodology conducted in the Finnish national nuclear energy research programme SAFIR (2003-2006). The purpose of this work was to increase the accuracy of risk estimates used in RI-ISI analyses of nuclear power plant (NPP) piping systems, and to quantitatively evaluate the effects of different piping inspection strategies on risk. Piping failure occurrences were sampled by using probabilistic fracture mechanics (PFM) analyses. The PFM results for crack growth were used to construct transition matrices for a discrete-time Markov process model, which in turn was applied to examine the effects of various inspection strategies on the failure probabilities and risks. The applicability of the developed quantitative risk matrix approach was examined as a pilot study performed to the Shut-down cooling piping system 321 in NPP unit OL1 of Teollisuuden Voima Oy (TVO). The analysed degradation mechanisms were stress corrosion cracking (SCC) and thermal fatigue induced cracking (in the mixing points). Here a new and rather straightforward approach was developed to model thermal fatigue induced cracking, which degradation mechanism is much more difficult to model than SCC. This study further demonstrated the usefulness of Markov analysis procedure development by VTT in RI-ISI applications. The most important results are the quantified comparisons of different inspections strategies. It was shown in this study that Markov models are useful for this purpose, when combined with PFM analyses. While the numerical results could benefit from further considerations of inspection reliability, this does not affect the feasibility of the method itself. The approach can be used to identify an optimal inspection strategy for achieving a balanced risk profile of piping segments. (orig.)

  15. Risk-Informed Decisions Optimization in Inspection and Maintenance

    International Nuclear Information System (INIS)

    Robertas Alzbutas

    2002-01-01

    The Risk-Informed Approach (RIA) used to support decisions related to inspection and maintenance program is considered. The use of risk-informed methods can help focus the adequate in-service inspections and control on the more important locations of complex dynamic systems. The focus is set on the highest risk measured as conditional core damage frequency, which is produced by the frequencies of degradation and final failure at different locations combined with the conditional failure consequence probability. The probabilities of different degradation states per year and consequences are estimated quantitatively. The investigation of inspection and maintenance process is presented as the combination of deterministic and probabilistic analysis based on general risk-informed model, which includes the inspection and maintenance program features. Such RIA allows an optimization of inspection program while maintaining probabilistic and fundamental deterministic safety requirements. The failure statistics analysis is used as well as the evaluation of reliability of inspections. The assumptions regarding the effectiveness of the inspection methods are based on a classification of the accessibility of the welds during the inspection and on the different techniques used for inspection. The probability of defect detection is assumed to depend on the parameters either through logarithmic or logit transformation. As example the modeling of the pipe systems inspection process is analyzed. The means to reduce a number of inspection sites and the cumulative radiation exposure to the NPP inspection personnel with a reduction of overall risk is presented together with used and developed software. The developed software can perform and administrate all the risk evaluations and ensure the possibilities to compare different options and perform sensitivity analysis. The approaches to define an acceptable level of risk are discussed. These approaches with appropriate software in

  16. Spanish guideline for the definition and assessment of risk-informed inservice inspection programs for piping

    Energy Technology Data Exchange (ETDEWEB)

    Figueras, J.M.; Olivar, F.; Mendoza, C.; Vazquez, T. [CSN, Madrid (Spain); Morales, L. [UNESA, Madrid (Spain); Bros, J.; Mach, I. [Tecnatom, Madrid (Spain); Gutierrez, E. [Iberinco, Madrid (Spain)

    2001-07-01

    The recent emphasis on risk-informed in-service inspection has been taken on by the Spanish Utilities and the Spanish Regulatory Body in their proposal for a co-operation project for defining a Risk-Informed In-Service Inspection Guideline for Piping. This paper describes first the main features of this Spanish guideline and then the results of the pilot applications developed in order to check the consistency of the guideline. (authors)

  17. Spanish guideline for the definition and assessment of risk-informed inservice inspection programs for piping

    International Nuclear Information System (INIS)

    Figueras, J.M.; Olivar, F.; Mendoza, C.; Vazquez, T.; Morales, L.; Bros, J.; Mach, I.; Gutierrez, E.

    2001-01-01

    The recent emphasis on risk-informed in-service inspection has been taken on by the Spanish Utilities and the Spanish Regulatory Body in their proposal for a co-operation project for defining a Risk-Informed In-Service Inspection Guideline for Piping. This paper describes first the main features of this Spanish guideline and then the results of the pilot applications developed in order to check the consistency of the guideline. (authors)

  18. Study on practical application of risk informed inservice inspection

    International Nuclear Information System (INIS)

    Sato, Chikahiro; Machida, Hideo; Takeda, Shuhei; Miyata, Koichi; Nishino, Shoichiro

    2009-01-01

    This paper describes pilot study relevant to the application of risk informed inservice inspection (RI-ISI) to class 1 piping systems in a Japanese typical BWR5 plant. The benefits of making use of risk information are improvement in plant safety, quality of inspection and explanation of security activities in nuclear power plants. The current RI-ISI procedures and rules were developed to take advantage of lessons learned from PSA data and piping failure experiences, and are expected to rationalize of security activities for plant operation and maintenance. To introduce RI-ISI, it is necessary to collaborate with industry, academia and government. Development of the technical basis is one of the key issues to become practical of RI-ISI programs. (author)

  19. Risk informed inservice inspection evaluation of the ComEd nuclear plants

    International Nuclear Information System (INIS)

    Fleming, K.N.; Hutchinson, J.J.

    2000-01-01

    In November, 1999 Commonwealth Edison Company began the largest scope project yet performed to implement risk informed in-service inspection programs for piping systems. A contractor team led by ERIN Engineering and Research was selected to perform full scope risk informed evaluations on ten reactor units at five sites including 3 BWR and 2 PWR stations. This risk informed evaluation has applied a number of advancements to RISI technology in key areas including risk quantification of inspection program changes, element selection, treatment of multiple damage mechanisms at a given location, and in streamlining an approach to RISI initially developed by EPRI. The scope of the evaluation covered more than 18,000 ASME Class 1 and 2 welds not counting those that will continue to be inspected as part of augmented programs for flow accelerated corrosion, stress corrosion cracking, and service water systems. When the current ASME Section XI based exams are replaced by the risk informed program, while some new inspection locations will be added, substantial cost savings and person-rem exposures are projected from the elimination of most of the current exams. ComEd expects to recover its investment in the RISI evaluation for each of the 10 reactor units in 1 to 2 refueling outages, from the cost savings of reduced inspections. At the same time, the risk of a severe accident due to pipe ruptures is not expected to exhibit significant changes. (author)

  20. In-service inspection techniques

    International Nuclear Information System (INIS)

    Backfisch, W.; Zipser, R.R.

    1980-01-01

    The owner of a nuclear power plant (NPP) is obligated and interested to maintain - by regular maintenance and in-service inspections - the operational safety and availability of the plant for the subsequent operating period in a condition, as is specified as the basis of the erection and the last operational permits. In-service inspections are performed to verify the operational safety, and maintenance work is performed to guarantee the availability. Below, the typical in-service inspections of a light-water reactor NPP (operated on a pressurized-water reactor or on a boiling-water reactor) are described with details and examples of typical inspections, especially of recurrent performance tests of the systems. (orig./RW)

  1. Strategy of Risk-Informed Inspection for Secondary Systems in NPPs

    International Nuclear Information System (INIS)

    Kim, So Young; Heo, Gyun Young

    2012-01-01

    Recently, unexpected accidents such as large-scale blackout have been occurred due to increasing demand of electricity. The unplanned trips have great influence over the economics although they rarely affect the safety of system. Because the cost for inspection and maintenance is limited, it is beneficial not only economically to take follow-up action in a timely manner to prevent plant trip but also in safety by protecting against the risk which is occurred from trip. In nuclear power plants (NPPs), the importance about risk-informed service such as inspection, maintenance and replacement is becoming on the rise. Risk-informed techniques such as in-service test, in-service inspection, design guide change and etc. are already used in nuclear field but these techniques are applied focusing on primary system for safety-related regulatory issues. It is needed to consider the optimization of inspection informed risk for entire plant including secondary system which is not applied enough. The study about risk-based inspection for boilers in thermal power field is in progress actively, but not for turbine cycle, which is similar with nuclear industry. Today, the most of inspections or tests for turbine cycle are time-based maintenance, being performed on time. It is required to perform condition-based maintenance by evaluating risk analyzing both of probability and consequence simultaneously about damage mechanisms that can be predicted by equipment or devices configuring the secondary system. Probability of failure (POF) is analyzed in terms of materials' ageing mechanisms, but consequence of failure (COF) should be evaluated in terms of thermohydraulic condition then it is needed to check power loss and period of maintenance. This paper is going to propose the idea to quantify the consequence of failure using the fault tree and simulation for secondary system, and propose quantitative risk-informed inspection by these approaches

  2. Review of international developments and cooperation on Risk-Informed In-Service-Inspection (RI-ISI) and Non-destructive Testing (NDT) Qualification in OECD-NEA member countries- Responses to the questionnaire - CSNI/integrity and ageing working group

    International Nuclear Information System (INIS)

    2005-01-01

    In December 2000, the Committee on Nuclear Regulatory Activities (CNRA) and the Committee on the Safety of Nuclear Installations (CSNI) agreed to prepare a state-of-the art report addressing the present situation and regulatory aspects in NEA member countries on: - Risk based / risk informed in-service inspections (ISI) developments, - Qualification of NDT system to be used for the inspections. The CSNI gave mandate to the CSNI working group on the Integrity of Components and Structures (IAGE) to prepare the report. In order to get a good basis for compiling the report with an overview on the present situation in OECD countries and regulatory aspects on the further developments of RI-ISI and NDT qualification approaches a questionnaire was prepared. This questionnaire was organised in two parts. The first part addressed used risk based / risk informed ISI approaches and regulatory aspects on the further developments. The second part addressed used NDT qualification approaches and other measures for getting reliable inspection results as well as regulatory aspects on the further developments of qualification approaches. Some parts of the questionnaire addressed topics, which have been dealt with in other European or national programs. Available relevant information from these programs has been also collected. The questionnaire was circulated in 2003 among NEA member countries organisations. Appendix 1 contains the questionnaire. Appendix 2 contains the compilation of responses to the questionnaire. A workshop was organized to complement the questionnaire (NEA/CSNI/R(2004)9 Proceedings of the CSNI Workshop on 'International developments and cooperation on Risk-Informed In-Service- Inspection (RI-ISI) and Non-destructive Testing (NDT) Qualification' held in Stockholm, Sweden on 13-14 April 2004 and hosted by SKI). In addition to regulators, licensees, manufacturers and researchers, this workshop gathered international organisations (i.e. EC, IAEA) and the main

  3. In-service inspection and periodic testing

    International Nuclear Information System (INIS)

    Eisele, H.; Meyer, F.A.; Zipser, R.R.

    1981-01-01

    In-service inspections are performed to verify the operational safety, and maintenance work is performed to guarantee the availability. Below, the typical in-service inspections of a light-water reactor NPP (operated on a pressurized-water reactor/PWR/ or on a boiling-water reactor/BWR/) are described with details and examples of typical inspections, especially of recurrent performance tests of the systems. (orig./RW)

  4. In-service inspection and periodic testing

    International Nuclear Information System (INIS)

    Eisele, H.; Meyer, F.A.; Zipser, R.R.

    1980-01-01

    In-service inspections are performed to verify the operational safety, and maintenance work is performed to guarantee the availability. In the present paper, the typical in-service inspections of a light-water reactor NPP (operated on a pressurized-water reactor/PWR/ or on a boiling-water reactor/BWR/) are described with details and examples of typical inspections, especially of recurrent performance tests of the systems. (orig./RW)

  5. Targeted In-service Inspections Using Risk Insights

    International Nuclear Information System (INIS)

    Kulat, S.; Montgomery, B.; Robin Graybeal, M.

    2012-01-01

    This paper includes a discussion of the historical background and rationale for development of a targeted In-service Inspection (ISI) program using risk insights, known as Risk-Informed In-service Inspection (RI-ISI). RI-ISI programs are optimized inspection programs which target specific welds for inspection based upon potential degradation mechanisms and consequences of failure. Inspections are performed on those welds that are the highest contributors to plant risk. Additionally the inspections are tailored to detect the specific postulated degradation mechanisms. As a result, the numbers of inspections are reduced along with the associated cost and radiation exposure, while maintaining or improving the level of quality and safety. Provided in this paper are the basic principles of RI-ISI program development, and a summary of the impact of the implementation of such programs. For example, implementation of a Risk-Informed In-service Inspection program results in a reduction of both cost and radiation exposure. Cost savings are estimated at between USD 1,000,000 and USD 2,300,000 per unit per ten year interval for a Class 1 and2 RI-ISI application. Cost savings are estimated based on average cost per weld of USD 7600 for examination, including the following activities: erection and removal of scaffolding, removal and replacement of insulation, removal and replacement of interferences, weld preparation, examination, documentation, craft support. Reduction in radiation exposure is estimated at 75% to 90% for a Class 1 and2 RI-ISI application. Reduction in radiation exposure is due to the following factors: number of welds selected for examination decreases by 60% to 75%, surface examinations essentially eliminated, within a given risk category, welds can be selected for examination based on additional factors such as the minimization of radiation exposure.(author).

  6. Periodic and in-service inspection programs

    International Nuclear Information System (INIS)

    Dinu, M.

    2000-01-01

    Periodic and in-service inspection programs for Cernavoda NPP consists of periodic inspections of CANDU NPP components CSAN N-285.4 and CSAN N-285.4, in-service inspections and repair and modifications general inspection. Periodic inspection program document (PIPD) determines the systems and components subject to inspection, the category of the inspection, techniques, areas and other details.The current status of the inspection programs is presented, including containment , erosion/corrosion, pressure vessel support and snubbers, main steam lines inspection programs. Qualification program in Cernavoda NPP involves equipment qualification in the on-site laboratory, yearly certification, special equipment qualification in the National Institute of Metrology. All procedures are approved by the ISCIR (regulatory body for pressure vessel and lifting equipment) and CNCAN (National Commission on Nuclear Activities Control). Qualification of the personnel is performed according to the ISCIR Technical prescription CR 11/82 for up to 3 year period. Final qualification and licensing is performed by CNCAN

  7. International developments on implementation of Wog risk-informed inservice inspection methodology

    International Nuclear Information System (INIS)

    Balkey, K.R.; Bishop, B.A.; Canton, M.A.; Closky, N.B.; Haessler, R.L.; Kolonay, J.F.; Sharp, G.L.; Stevenson, P.R.

    2001-01-01

    The full text follows. The Westinghouse Owners Group (WOG) risk-informed inservice inspection (ISI) methodology was granted approval by the U.S. Nuclear Regulatory Commission in 1998 thereby providing an alternative to ASME Section XI Code requirements for the selection of examination locations in nuclear plant piping systems. This paper builds upon a technical paper presented at ICONE-8 that reported on the first wave of risk-informed ISI applications under development primarily focusing on those underway within the U.S. Since that time, many applications have continued within the U.S., however, much progress has been made in applying the WOG risk-informed ISI approach in several other countries. While a summary of results across the various applications will be provided, the paper will focus on the development and implementation of the WOG risk-informed ISI methodology across Europe and in Asia for both full scope and limited Class 1 scope applications. An update on future risk-informed applications, such as modifying requirements for augmented examinations for high energy line break exclusion regions and in risk-informing the safety classification of pressure boundary components in support of risk-informed regulation initiatives, will also be provided. (authors)

  8. Challenges in using a probabilistic safety assessment in a risk informed process (illustrated using risk informed inservice inspection)

    International Nuclear Information System (INIS)

    Chapman, James R.; Dimitrijevic, Vesna B.

    1999-01-01

    Many of the ongoing and expected uses of Probabilistic Safety Assessment (PSA) create new challenges to ensuring that the resulting conclusions are valid. This paper provides a summary of some of these challenges. Work conducted by the authors on Risk-Informed Inservice Inspection (RI-ISI) is used to illustrate these challenges. Means to address all of the challenges are not provided in detail in this paper. Several earlier papers discuss how these challenges can be addressed. References are provided for the interested reader (Chapman JR et al. In: PSA '95, vol. 1, Seoul, 1995: 177-80; Chapman JR et al. In: ICONE-IV, New Orleans, 1996; Dimitrijevic VB et al. In: Croatian Nuclear Society International Conference, Opatija, 1996: 245-54; Dimitrijevic VB et al. In: Croatian Nuclear Society International Conference, Opatija, 1996: 255-62; Dimitrijevic VB. In: Yugoslav Nuclear Society Conference, Belgrade, 1996: 53-61; O'Regan PJ et al. In: PSA '95, Seoul, vol. 1, 1995: 403-5; O'Regan PJ. In: ICONE-IV, vol. 5, New Orleans, 1996: 277-80)

  9. Designing for in-service inspection

    International Nuclear Information System (INIS)

    Dixit, K.B.

    2002-01-01

    The process of design of components, equipment and systems normally focuses on functional requirements, integrity and environmental conditions. Manufacturing processes, fabricability, inspectability and maintainability in service are considered while designing. Provisions for the requirements of ISI also need to be given due consideration while designing the systems, equipment and components

  10. Lessons Learned From Implementation of Westinghouse Owners Group Risk-Informed Inservice Inspection Methodology for Piping

    International Nuclear Information System (INIS)

    Stevenson, Paul R.; Haessler, Richard L.; McNeill, Alex; Pyne, Mark A.; West, Raymond A.

    2006-01-01

    Risk-informed inservice inspection (ISI) programs have been in use for over seven years as an alternative to current regulatory requirements in the development and implementation of ISI programs for nuclear plant piping systems. Programs using the Westinghouse Owners Group (WOG) (now known as the Pressurized Water Reactor Owners Group - PWROG) risk-informed ISI methodology have been developed and implemented within the U.S. and several other countries. Additionally, many plants have conducted or are in the process of conducting updates to their risk-informed ISI programs. In the development and implementation of these risk-informed ISI programs and the associated updates to those programs, the following important lessons learned have been identified and are addressed. Concepts such as 'loss of inventory', which are typically not modeled in a plant's probabilistic risk assessment (PRA) model for all systems. The importance of considering operator actions in the identification of consequences associated with a piping failure and the categorization of segments as high safety significant (HSS) or low safety significant (LSS). The impact that the above considerations have had on the large early release frequency (LERF) and categorization of segments as HSS or LSS. The importance of automation. Making the update process more efficient to reduce costs associated with maintaining the risk-informed ISI program. The insights gained are associated with many of the steps in the risk-informed ISI process including: development of the consequences associated with piping failures, categorization of segments, structural element selection and program updates. Many of these lessons learned have impacted the results of the risk-informed ISI programs and have impacted the updates to those programs. This paper summarizes the lessons learned and insights gained from the application of the WOG risk-informed ISI methodology in the U.S., Europe and Asia. (authors)

  11. Improvement and optimization for in-service inspection of M310 nuclear power station

    International Nuclear Information System (INIS)

    Wang Chen; Sun Haitao; Gao Chen; Deng Dong

    2015-01-01

    In-service inspection (ISI) is an important method to ensure the safety of the mechanical equipment in nuclear power stations. According to the in-service inspection experience feedback from the domestic nuclear power stations, the reasonableness of some provisions in the RSE-M code are discussed and the applications of risk-informed in-service inspection (RI-ISI) are introduced, and the advices for the optimization of the ISI of the domestic M310 nuclear power stations are proposed. (authors)

  12. Risk-informed optimisation of railway tracks inspection and maintenance procedures

    International Nuclear Information System (INIS)

    Podofillini, Luca; Zio, Enrico; Vatn, Jorn

    2006-01-01

    Nowadays, efforts are being made by the railway industry for the application of reliability-based and risk-informed approaches to maintenance optimisation of railway infrastructures, with the aim of reducing the operation and maintenance expenditures while still assuring high safety standards. In particular, in this paper, we address the use of ultrasonic inspection cars and develop a methodology for the determination of an optimal strategy for their use. A model is developed to calculate the risks and costs associated with an inspection strategy, giving credit to the realistic issues of the rail failure process and including the actual inspection and maintenance procedures followed by the railway company. A multi-objective optimisation viewpoint is adopted in an effort to optimise inspection and maintenance procedures with respect to both economical and safety-related aspects. More precisely, the objective functions here considered are such to drive the search towards solutions characterized by low expenditures and low derailment probability. The optimisation is performed by means of a genetic algorithm. The work has been carried out within a study of the Norwegian National Rail Administration (Jernbaneverket)

  13. In-service inspections of V-230 reactor

    International Nuclear Information System (INIS)

    Prepechal, J.

    1984-01-01

    It is stated that despite certain constraints the configuration of the WWER-440 is such that it allows to make in-service inspections on a fully satisfactory scale. Three factors are discussed whose existence is necessary for the implementation of in-service inspections. The program defining the scale of inspections is satisfactory with regard to the safety and reliability of reactor operation. Its further development must result in reducing time consumption and radiation burden of personnel. Regulations for the implementation and evaluation of inspections represent the weakest link in the system of in-service inspections. At present, various organizations are dealing with the said problem within international cooperation. Equipment for in-service inspections of WWER-440 reactors is relatively good. The most important knowledge is summed up gained from the ten pre-service and in-service inspections of reactors of this type made so far. (Z.M.)

  14. In-service inspection of pressurized water reactors

    International Nuclear Information System (INIS)

    Rapin, M.; Saglio, R.

    1983-01-01

    French legislation, which is more demanding than in other countries, had led Electricite de France, the State-owned utility, to acquire better performance in-service inspection facilities than those which existed previously. This fact has spurred the industrial development of the new technical facilities which are used worldwide today. This article presents the ''in-service inspection machine'' (MIS) for the inspection of the welds of a PWR vessel, and the inspection device of steam generator tubes; the MIS allow a remote-viewing, ultrasonic and gamma-graphic inspection; Foucault currents are the only one method adapted to the inspection steam generator tubes [fr

  15. The new French code for PWR in service inspection

    Energy Technology Data Exchange (ETDEWEB)

    Noel, R; Hutin, J P [Electricite de France (EDF), 75 - Paris (France)

    1988-12-31

    This document presents the new french code for pressured water reactor in service inspection. The historic regulatory basis is presented, together with the new regulatory act (dating back to the 26 february 1974) and the major guidelines of the french practice for in service inspection of PWR components. (TEC).

  16. Aspects of the Optimization on the In-Service Inspection

    International Nuclear Information System (INIS)

    Korosec, D.; Vojvodic Tuma, J.

    2002-01-01

    In the present paper, the aspects of optimizing In-Service Inspection (ISI) is discussed. Slovenian Nuclear Safety Administration (SNSA) and its authorized organization for the ISI activities, Institute of Metals and Technologies, are actually permanently involved in the ISI processes of the nuclear power plant (NPP) Krsko. Based on the previous experience on the ISI activities, evaluation of the results and review of the new ISI program, the decision was made to improve recent regulatory and professional practice. That means, the conclusion was made to optimize the evaluation process of the ISI as a process. Traditional criteria, standards and practice gives good fundament for the improvements implementation. Improvements can be done on the way that the more broad knowledge about safety important components of the systems shall bee added to the basic practice. It is necessary to identify conditions of the safety important components, such as realistic stress and fatigue conditions, material properties changes due aging processes, the temperature cycling effects, existing flaws characterization in the light of the previous detection and equipment technique used, assessment of the measurement accuracy on the results etc. In addition to the above mentioned, risk assessment and evaluation of the whole ISI shall be done. To do this it is necessary to made risk evaluation, based on previous structural element probability assessment. Probabilistic risk assessment is important and one of the most powerful tools in the ISI optimization. Some basic work on the filed of the risk informed methods related to the nuclear safety components has been already done. Based on reference documentation, the most important steps in risk informed ISI are discussed: scope definition, consequence evaluation, failure probability estimation, risk evaluation, non-destructive examination method selection and possibilities of implementation, monitoring and feedback. Recent experience on the ISI

  17. New Swedish regulations in the area of plant inspection and in-service inspection

    International Nuclear Information System (INIS)

    Hansson, B.

    1998-01-01

    History and present status od Swedish regulations in the field of NPP inspection and in-service inspection are described. The presentation focuses on the development of regulations and establishing new ones. A description of different organisations involved is included

  18. In-service inspection guidelines for composite aerospace structures

    International Nuclear Information System (INIS)

    Heida, Jaap H.; Platenkamp, Derk J.

    2012-01-01

    The in-service inspection of composite aerospace structures is reviewed, using the results of a evaluation of promising, mobile non-destructive inspection (NDI) methods. The evaluation made use of carbon fibre reinforced specimens representative for primary composite aerospace structures, including relevant damage types such as impact damage, delaminations and disbonds. A range of NDI methods were evaluated such as visual inspection, vibration analysis, phased array ultrasonic inspection, shearography and thermography inspection. Important aspects of the evaluation were the capability for defect detection and characterization, portability of equipment, field of view, couplant requirements, speed of inspection, level of training required and the cost of equipment. The paper reviews the damage tolerance design approach for composites, and concludes with guidelines for the in-service inspection of composite aerospace structures.

  19. Improvement of in-service inspection in nuclear power plants

    International Nuclear Information System (INIS)

    2004-07-01

    During the nuclear power plant's (NPPs) operating lifetime, the operating organisation should examine the systems, structures and components (SSCs) for possible deterioration so as to determine whether they are acceptable for continued safe operation or whether remedial measures should be taken. In-service inspection (ISI) provides the systematic framework for these examinations. An effective ISI programme ensures both that the safety of the plant is not adversely affected after the commencement of operation and that the levels of reliability and availability of all plant SSCs remain in accordance with the assumptions and intent of the design and, consequently, a cost effective electricity generation is guaranteed. This report was prepared under one of the IAEA projects, 'Integrated NPP life cycle management including decommissioning'. The main objective of an integrated life cycle management programme is to enable NPPs to compete, without compromising safety, successfully in the changing energy markets throughout their service life and to facilitate life extension and eventual decommissioning through improved engineering, technological, economic and managerial actions. The Technical Working Group on NPP Life Management and other advisory groups nominated by the Member States provide recommendations on high priority needs of Member States in this area. The purpose of this TECDOC is to: discuss and evaluate the status of ISI and its evolution in NPPs of IAEA Member States; discuss and evaluate the criteria for effective ISI and the constitutive elements; discuss and evaluate the implication of the introduction of risk informed ISI (RI-ISI) concepts; generate a common recommendation as to how to benefit from utilising the potential of RI-ISI concepts for further development and, possibly, improvement of ISI effectiveness. The specific concept of this report is to treat the two key issues, i.e. inspection qualification and RI-ISI, and their complementarities, to

  20. Enhanced InService Inspection system for BWR plant

    International Nuclear Information System (INIS)

    Shouji, Hajime; Kobayashi, Teruo; Nagao, Tetsuya

    1993-01-01

    An enhanced InService Inspection system (ISI) has been developed, consisting of newly designed automated scanners, automated pipe inspection system and a high speed data acquisition/analysis station. This system uses a trackless magnetic crawler type nozzle inspection scanner attached to the nozzle shoulder by magnetic wheels. The automated pipe inspection system consists of an automated scanner, controller and high speed data acquisition station. These advanced automatic inspection systems are very useful for ISI, especially in reducing the radiation exposure and time required. (author)

  1. In service inspection of superphenix 1 vessels: MIR

    International Nuclear Information System (INIS)

    Asty, M.; Viard, J.; Lerat, B.; Saglio, R.

    1985-02-01

    Presentation of the in-service inspection device, MIR, which has been specially developed for the visual and ultrasonic examination of Super Phenix 1 vessels (surface and internal defects). The inspections take place during fuel handling operations. The inspection device is a robot with a four-wheel drive vehicle which guidance along the welds is achieved by eddy-current devices; visual examination is performed by a television camera and ultrasonic probes are specially resistent to high temperatures

  2. In-service inspection in the Superphenix 1 vessels interspace

    International Nuclear Information System (INIS)

    Asty, M.; Saglio, R.

    1983-03-01

    The design of Superphenix 1 reactor vessels allows their in-service inspection. A self-propelling engine, the MIR, has been concieved for this need: it can do a visual and ultrasonic inspection. The MIR can move in the whole vessels interspace. The operating conditions are specified and the principle characteristics of the MIR engine are presented [fr

  3. Advanced Approach of Reactor Pressure Vessel In-service Inspection

    International Nuclear Information System (INIS)

    Matokovic, A.; Picek, E.; Pajnic, M.

    2006-01-01

    The most important task of every utility operating a nuclear power plant is the continuously keeping of the desired safety and reliability level. This is achieved by the performance of numerous inspections of the components, equipment and system of the nuclear power plant in operation and in particular during the scheduled maintenance periods at re-fueling time. Periodic non-destructive in-service inspections provide most relevant criteria of the integrity of primary circuit pressure components. The task is to reliably detect defects and realistically size and characterize them. One of most important and the most extensive examination is a reactor pressure vessel in-service inspection. That inspection demand high standards of technology and quality and continual innovation in the field of non-destructive testing (NDT) advanced technology as well as regarding reactor pressure vessel tool and control systems. A remote underwater contact ultrasonic technique is employed for the examination of the defined sections (reactor welds), whence eddy current method is applied for clad surface examinations. Visual inspection is used for examination of the vessel inner surface. The movement of probes and data positioning are assured by using new reactor pressure vessel tool concept that is fully integrated with NDT systems. The successful performance is attributed thorough pre-outage planning, training and successful performance demonstration qualification of chosen NDT techniques on the specimens with artificial and/or real defects. Furthermore, use of advanced approach of inspection through implementation the state of the art examination equipment significantly reduced the inspection time, radiation exposure to examination personnel, shortening nuclear power plant outage and cutting the total inspection costs. The advanced approach as presented in this paper offer more flexibility of application (non-destructive tests, local grinding action as well as taking of boat samples

  4. Laurels for Swiss in-service inspection team

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Following what is believed to be the first successful application of P-scan ultrasonic testing for the in-service inspection of austenitic welds in the boiling water reactor at Wuergassen (Federal Republic of Germany) last year, Sulzer participated in a 'round robin' test organized by the Electric Power Research Institute in the USA form May to July 1983. (Auth.)

  5. Interaction between periodic in-service inspection requirements and design

    International Nuclear Information System (INIS)

    Prot, A.C.; Saglio, R.

    1979-03-01

    After reviewing the requirements specific of periodic In-Service Inspection related to safety problems, especially for the pressure vessels, and taking into account the experience gained with several PWR reactors, the authors show these requirements could lead to modify the primary circuit design

  6. PWR reactor vessel in-service-inspection according to RSEM

    International Nuclear Information System (INIS)

    Algarotti, Marc; Dubois, Philippe; Hernandez, Luc; Landez, Jean Paul

    2006-01-01

    Nuclear services experience Framatome ANP (an AREVA and Siemens company) has designed and constructed 86 Pressurized Water Reactors (PWR) around the world including the three units lately commissioned at Ling Ao in the People's Republic of China and ANGRA 2 in Brazil; the company provided general and specialized outage services supporting numerous outages. Along with the American and German subsidiaries, Framatome ANP Inc. and Framatome ANP GmbH, Framatome ANP is among the world leading nuclear services providers, having experience of over 500 PWR outages on 4 continents, with current involvement in more than 50 PWR outages per year. Framatome ANP's experience in the examinations of reactor components began in the 1970's. Since then, each unit (American, French and German companies) developed automated NDT inspection systems and carried out pre-service and ISI (In-Service Inspections) using a large range of NDT techniques to comply with each utility expectations. These techniques have been validated by the utilities and the safety authorities of the countries where they were implemented. Notably Framatome ANP is fully qualified to provide full scope ISI services to satisfy ASME Section XI requirements, through automated NDE tasks including nozzle inspections, reactor vessel head inspections, steam generator inspections, pressurizer inspections and RPV (Reactor Pressure Vessel) inspections. Intercontrole (Framatome ANP subsidiary dedicated in supporting ISI) is one of the leading NDT companies in the world. Its main activity is devoted to the inspection of the reactor primary circuit in French and foreign PWR Nuclear Power Plants: the reactor vessel, the steam generators, the pressurizer, the reactor internals and reactor coolant system piping. NDT methods mastered by Intercontrole range from ultrasonic testing to eddy current and gamma ray examinations, as well as dye penetrant testing, acoustic monitoring and leak testing. To comply with the high requirements of

  7. In service inspection of pipes based on risk methods

    International Nuclear Information System (INIS)

    Mendoza G, G.; Viais J, J.; Carmona C, M.

    2006-01-01

    The politics of the Nuclear Regulatory Commission (by its initials in English NRC) of the United States of America on the use of the Probabilistic Safety Analysis (PSA) in activities of nuclear regulation it foments the use of this analysis technique to improve the decisions making, to reduce the unnecessary work in maintenance aspects, inspection and tests and to improve the regulatory efficiency. The inspection programs in service (ISI by its initials in English) developed by the American Society of Mechanical Engineers (by its initials in English ASME) it has been the one primary mechanism to prove the mechanical equipment in plants of nuclear energy, these programs indeed have been carried out in plants of nuclear energy by more of two decades. Their purpose is to identify the conditions, such as indications of cracks that are precursory of flights and ruptures which violate the integrity principles of the pressure frontier. The inspection in service activities include ultrasonic tests, surface tests and penetrating liquids test, also activities that include the scaffolds construction, removal of insulations and welding polishing. The inspections in service every 18 months during the times outside of service are executed. One of the objectives is to lower the costs of the inspections during the times outside of service and to reduce the exposure to the radiation by part of the personnel during these times out for inspections, while it is increased or it maintains the personnel's safety and the reliability. As part of the methodology a pipe segment is selected for which a fault in any point has the same consequences, being calculated the fault probability of the tube using the dimensions of the segment. In this work the inspection in service methodology is applied based on risk to an aspersion system of low pressure of the Laguna Verde Nucleo electric Central. For this system a reduction in the number of welding to inspect of 103 to only 15 is obtained

  8. In service inspection of SUPERPHENIX 1 vessels: MIR

    International Nuclear Information System (INIS)

    Asty, M.; Viard, J.; Lerat, B.; Saglio, R.

    1985-01-01

    Although no in-service inspection constraints were imposed on the Phenix vessels, the Safety Authorities asked that the design of SUPERPHENIX 1 makes it possible to monitor throughout the lifetime of the reactor, surface and internal defects on the main vessel. A pool design and the presence of heat baffles inside the main vessel make access from the inside of the vessel impossible. Thus, an inspection can only be performed from the outside of the main vessel: the distance between the walls of the main and safety vessels is such that an inspection device can be introduced into the corresponding space. As the design of the reactor precludes radiographic inspection, the method which was selected for monitoring internal defects in the main vessel is ultrasonics. However, the anisotropic structure of austenitic stainless steel welds limits the performance of this technique. The authors present the in-service inspection device, MIR, which has been specially developed for the visual and ultrasonic examination of SUPERPHENIX 1 vessels

  9. In-service inspection of nuclear power plants

    International Nuclear Information System (INIS)

    Asty, M.; Saglio, R.

    1984-10-01

    The French Commissariat a l'Energie Atomique (Atomic Energy Commission) developed two new non destructive control techniques, focused ultrasonics and multi-frequency eddy currents, which have been shown to allow a better detection and characterization of defects. We present here some of the in-service inspection devices which have been designed for field application of these techniques on the PWR reactors built by EDF, inspection devices of the PWR steam generator tubing and the now developing specific device for main tank and helicoidal tubing steam generator of Super-Phenix 1 [fr

  10. Pre-service inspection and in-service inspection in Japan

    International Nuclear Information System (INIS)

    Uebayashi, T.; Miyake, Y.

    1985-01-01

    To ensure the safety of nuclear power plant, pre-service inspection/in-service inspection (PSI/ISI) has an important role, and informations obtained from various inspections during plant shut-down period are contributing to establish effective preventive maintenance activities for plant facilities. It might be said that the high level of availability of Japanese light-water nuclear power plants in these two or three years has been achieved by those efforts. In case of Japan, inspections to be carried out during scheduled plant shut-down period are not limited to code requirements but include many other inspections which are mostly reflected from troubles experienced in both domestic and overseas plants. Usually, those additional inspections are performed by Ministry of Trade and Industries' (MITI's) regulator and/or tentative requirement and considered as ISI in broad meaning. To achieve high availability of plant, it is essential to avoid unscheduled shut-down and to shorten inspection period. The developments of new technology to perform effective ISI for operating plants are continued, but on the other hand it is also very important to pay a great consideration to inspectability of the plants at the stage of plant engineering. With the leadership of MITI, improvement and standardization of light-water nuclear power plant has been proceeded and newly constructed plants have great advantage from the point of view on ISI

  11. Review of activities relevant to in-service inspection

    International Nuclear Information System (INIS)

    Imanaka, N.

    1980-01-01

    Nuclear power plants are requested to provide continuing safety that cannot compare with other industries, as plant safety is a matter of much concern. To provide continuous assurance for plant safety there is increasing tendency to demand much of inspection of components during the lifetime. This inservice inspection of LMFBRs should be investigated from a view point of different systems and characteristics from LWRs. In this paper a review for inservice inspection of LMFBRs is described. To provide a continuous assurance of safety to the LMFBR, it is essential to develop how to construct the components to maintain the integrity throughout the service lifetime. Especially how to design is urged for this object. In-service inspection should be located only to compensate some uncertainty remained at the design stage, as it is too much complex in practice. As for inspection techniques, leak monitoring is assumed to be a best way to assure the plant safety continuously with the minimum plant outage time and minimum radioactive hazard to the inspectors

  12. In-service inspection of nuclear power plants

    International Nuclear Information System (INIS)

    1991-01-01

    This Manual is intended to provide more comprehensive considerations on the management, organization, preparation, improvement and implementation of in-service inspection activities and the related surveillance. It also gives illustrative examples of good practices and recommendations from operating and other organizations that are consistent with the requirements and recommendations of the Code and Safety Guides. The Manual is directed primarily towards plant management. This Manual should be used in conjunction with the Code and the Safety Guides, in particular with IAEA Safety Series Nos. 50-C-O, 50-SG-O2, 50-SG-05, 50-SG-07, 50-SG-08 and 50-SG-D1, which contain recommendations of a general character about maintenance activities and radiation protection in an operating power plant, and with the 'Manual on the Maintenance of Systems and Components Important to Safety'. This Manual is divided into four technical sections. The first introduces the purpose, structure and main requirements of the programme. The second section describes constituents of the programme, recommending its scope, scheduling, acceptance standards and documentation of results. The following section goes into details of the inspection programme's contents, such as the selection of components, inspection locations, defect types, applicable techniques and procedures, and the evaluation of results. The last section specifies recommended methods and techniques for inspection, such as visual, ultrasonic, eddy current, magnetic particle and others. This main part of the Manual is complemented by a number of annexes which reproduce actual national examples of established procedures, ISI programme parts, acceptance standards, personnel training programmes, testing techniques and other aspects of in-service inspection, illustrating practical implementation of the recommendations of the Manual

  13. Risk-informed importance analysis of in-service testing components for Ulchin units 3 and 4

    International Nuclear Information System (INIS)

    Kang, D. I.; Kim, K. Y.; Ha, J. J.

    2001-01-01

    In this paper, we perform risk-informed importance analysis of in-service tesing (IST) components for Ulchin Units 3 and 4. The importance analysis using PSA is performed through Level 1 internal and external, shutdown/low power operation, and Level 2 internal PSA. The sensitivity analysis is also performed. For the components not modeled in PSA logic, we develop and apply a new integrated importance analysis method. The importance analysis results for IST valves show that 167 (26.55%) of 629 IST valves are HSSCs and 462 (73.45%) are LSSCs. The importance analysis results for IST pumps show that 28 (70%) of 40 IST pumps are HSSCs and 12 (30%) are KSSCs

  14. Implementation of in-service inspection program for HANARO

    International Nuclear Information System (INIS)

    Wu, J.S.; Park, Y.C.; Cho, Y.G.; Jun, B.J.

    2001-01-01

    HANARO, a 30 MW multi-purpose research reactor in Korea has been successfully in operation for 6 years since its initial criticality in February 1995. It is mainly used for the research areas including nuclear fuel and material irradiation tests, radioisotope production, neutron beam application, neutron activation analysis and neutron transmutation doping. HANARO was designed to perform for at least 20 years under full power operating condition. It is expected that the actual reactor lifetime will be much more than the design lifetime, due to a safety reassessment based on realistic data, preventive maintenance and appropriate in-service inspections (ISI). Since ageing may affect the overall safety of the reactor facility, it is needed to detect and evaluate the effects on aged components and systems related to safety. During the lifetime of the reactor, structures, systems and components are subjected to environmental conditions of stress, temperature and irradiation that may lead to changes in the material properties and could result in unexpected failures. Evidence of ageing problems appears progressively. A rigorous inspection and visual examination based on a periodic ISI program should be established. It is desirable that the ageing surveillance activities is scheduled as early as possible and continued throughout the operating life of the reactor. An inspection plan for safety related structures, systems and components subjected to the ageing conditions is requested by the regulatory body to assess the safety status of reactor facility. A long-term ISI program for HANARO has been established for safety-related systems and components in the context of the overall reactor ageing management. The objective of this paper is to describe the ISI program and the result of the visual inspection as the first ISI. (orig.)

  15. In-service inspection methods for graphite-epoxy structures on commercial transport aircraft

    Science.gov (United States)

    Phelps, M. L.

    1981-01-01

    In-service inspection methods for graphite-epoxy composite structures on commercial transport aircraft are determined. Graphite/epoxy structures, service incurred defects, current inspection practices and concerns of the airline and manufacturers, and other related information were determind by survey. Based on this information, applicable inspection nondestructive inspection methods are evaluated and inspection techniques determined. Technology is developed primarily in eddy current inspection.

  16. Applicability of PSA Issues for Risk Assessment during Optimisation of In-Service Inspection

    International Nuclear Information System (INIS)

    Kolykhanov, V.; Skalozubov, V.; Kovrigkin, Y.

    2006-01-01

    The current codes determining periodicity of in-service inspection of the NPP equipment have been formed using deterministic approaches and have an unnecessary degree of conservatism. A perspective direction of perfection of normative base is decision making on a basis of risk-informed methodologies. It allows to increase safety of NPP equipment's operation and to optimise programs on inspection of the equipment subject to limited resources by focusing efforts on the most safety significant elements of the equipment. It is internationally accepted that methodology of the probabilistic safety analysis (PSA) is the most universal and comprehensive tool focused on the general assessment of safety of NPP as a whole. By now, PSA Level 1 is fulfilled for all pilot units of the Ukrainian NPPs that is a valuable result, which should be taken into account at an assessment of reliability of the equipment. However, specificity of PSA methodology should be taken into account at the decision of the particular tasks aimed at optimisation of maintenance of the equipment within individual systems. The estimation of the contribution to core damage frequency (CDF) is a PSA issue usually used to assess the significance of consequences of failure of a system/equipment during risk-informed decision-making. This work shows that above factor is only a part of assessment of the significance of consequences as core damage can be expressed in different amount of the damaged fuel elements and, hence, severity of consequences. Besides CDF is directly affected only by active elements which failure can be an initiating event. PSA methodology uses averaged reliability factors of the equipment for all possible operating modes occurring at transitive accident process. Here, there are limited opportunities to account impact of periodicity of maintenance of the equipment on reliability and to predict impact of change of the inspection program. PSA methodology does not allow taking into account

  17. Status report on developments and cooperation on risk-informed inservice-inspection and non-destructive testing (NDT) qualification in OECD-NEA member countries - CSNI integrity and ageing working group

    International Nuclear Information System (INIS)

    Skanberg, Lars

    2005-01-01

    During the last decades the nuclear industry has experienced service degradation of many components, both in primary systems and in secondary systems. Several inspection failures have also occurred over the years. This degradation and inspection history as well as the economical and political factors have consequently set up a pressure for more efficient and cost-effective in-service inspection programmes to ensure that there are adequate safety margins so that anticipated degradations of components do not lead to failures that cause accidents or even unplanned shutdowns with adverse effects on power production reliability. In this situation, nuclear regulators as well as nuclear utilities in many countries have developed and implement risk-informed inspection approaches together with more stringent requirements of demonstrating the performance of the NDT systems that are to be used for inspection of safety related components which are susceptible to different kind of degradation mechanisms. In December 2000, the Committee on Nuclear Regulatory Activities (CNRA) and the Committee on the Safety of Nuclear Installations (CSNI) agreed to prepare a state-of-the art report addressing the present situation and regulatory aspects in NEA member countries on: - Risk based / risk informed in-service inspections developments, - Qualification of NDT system to be used for the inspections. The CSNI gave mandate to the CSNI working group on the Integrity of Components and Structures (IAGE) to prepare the report. Practices and status in NEA member countries were collected in 2003 through a questionnaire. Results have been compiled in the report NEA/CSNI/R(2005)3. To complete the technical information, a CSNI Workshop was held from 13 to 14 April 2004 in Stockholm, Sweden hosted by the Swedish Nuclear Power Inspectorate. The Workshop gathered 54 participants from 17 countries including the EC, the IAEA and the main organisations worldwide developing RI-ISI methodologies. Papers

  18. Surveillance and in-service inspection (SISI) program at FFTF

    International Nuclear Information System (INIS)

    Conrads, T.J.

    1980-01-01

    Assurance of the integrity of the sodium coolant pressure boundaries of the Fast Flux Test Facility systems and components is essential for safe operation. A program has been developed to monitor the integrity of the coolant boundaries and certain plant conditions. Specific equipment and features have been designed into the plant for monitoring. The purpose of SISI is to prevent failures or minimize their consequences through early detection. The program which administers the requirements for monitoring applicable plant conditions whose integrity is necessary to protect public health and safety is known as the Surveillance and In-service Inspection (SISI) Program. The SISI program utilizes a wide range of monitoring techniques to ensure that material degradation or structural deficiencies will not result in the loss of the ability to shut down the reactor, cool the reactor core, or cause the release of radioactive material to the environment

  19. In service inspection and repair of sodium cooled ASTRID prototype

    Energy Technology Data Exchange (ETDEWEB)

    Baque, F.; Jadot, F. [French Atomic Commission, Cadarache Centre, 13108 Saint Paul lez Durance Cedex, (France); Marlier, R. [AREVA, 10 rue Recamier, 69456 Lyon cedex 06, (France); Saillant, J-F. [AREVA/NDE Solutions, 4 rue Thomas Dumorey, BP 70385, 71109 Chalon sur Saone Cedex, (France); Delalande, V. [EDF R and D, 6, quai Watier, 78400 Chatou, (France)

    2015-07-01

    In the frame of the large R and D work which is performed for the future ASTRID sodium cooled prototype, In Service Inspection and Repair (ISI and R) has been identified as a major issue to be taken into account in order to enlarge the plant safety, to consolidate its availability and to protect the associated investment. After the first part of pre-conceptual design phase (2008-2012), the running second part of pre-conceptual phase (2013-2015) allows to increase the ISI and R tool ability for immersed sodium structures of ASTRID, at about 200 deg. C, on the basis of consolidated specifications and thanks to their qualification through more and more realistic laboratory tests and simulation with CIVA code. ISI and R items are being developed and qualified during a pluri-annual program which mainly deals with the reactor block structures, the primary components and circuit, and the Power Conversion System. It ensures a strong connection between the reactor designers and inspection specialists, as the optimization of inspectability and repairability is looked at: this already induced specific rules for design, in order to shorten and ease the ISI and R operations, which have been merged into RCC-MRx rules. In the frame of increasing technology readiness level with corresponding performance demonstration, this paper presents R and D dealing with the ISI and R items: it highlights the sensor development (both ultrasonic and electromagnetic concepts, compatible with sodium at 200 deg. C), then their applications for ASTRID structure control (under sodium telemetry, imaging and NDE). Activity for repair is also presented (a single laser tool for sodium sweeping, machining and welding), and finally the effort for associated robotic (generic program for ASTRID applications, specific technological tools for sodium medium, tight immersed bell). The main results of testing and simulation are given for telemetry, vision, NDE applications, laser process repair and under sodium

  20. In-service inspection robot for PFBR main vessel- concept

    Energy Technology Data Exchange (ETDEWEB)

    Rajendran, S; Ramakumar, M S [Bhabha Atomic Research Centre, Mumbai (India). Div. of Remote Handling and Robotics

    1994-12-31

    In-service inspection (ISI) of critical components in a nuclear reactor is one of the foremost and important tasks which reveals the state of health of the system, thereby ensuring the safety of the plant, personnel and environment. Prototype Fast Breeder Reactor (PFBR) is designed as a pool type reactor. A safety vessel is provided in the design which envelopes the main reactor vessel. The ISI of the main vessel is mandatory and will be carried out by a robot which will operate on this annular gap. The design of the robot is such that it can crawl around the vessel and into the gap at the bottom of the vessel relying on friction grip. The mobile robot will carry a CCTV camera and the inspection technique packages into the interspace, position and orient these to carry out the ISI of the main vessel. The paper discusses about the design features of the robot including the gripping mechanism and the crawling sequence to perform ISI of the reactor vessel. 3 figs.

  1. In-service inspection robot for PFBR main vessel- concept

    International Nuclear Information System (INIS)

    Rajendran, S.; Ramakumar, M.S.

    1994-01-01

    In-service inspection (ISI) of critical components in a nuclear reactor is one of the foremost and important tasks which reveals the state of health of the system, thereby ensuring the safety of the plant, personnel and environment. Prototype Fast Breeder Reactor (PFBR) is designed as a pool type reactor. A safety vessel is provided in the design which envelopes the main reactor vessel. The ISI of the main vessel is mandatory and will be carried out by a robot which will operate on this annular gap. The design of the robot is such that it can crawl around the vessel and into the gap at the bottom of the vessel relying on friction grip. The mobile robot will carry a CCTV camera and the inspection technique packages into the interspace, position and orient these to carry out the ISI of the main vessel. The paper discusses about the design features of the robot including the gripping mechanism and the crawling sequence to perform ISI of the reactor vessel. 3 figs

  2. Risk-informed regulation

    International Nuclear Information System (INIS)

    Hoffman, D.R.

    2003-01-01

    In assessing safety for nuclear facilities, regulators have traditionally used a deterministic approach. New techniques for assessing nuclear or radiological risks make it possible for regulators to incorporate risk insights into their regulations. By 'risk-informing' the regulatory processes, independent bodies tasked with protecting the health and safety of the public can focus on those design and operational issues most important to safety. Such an approach is a move away from prescriptive regulations that were based on conservative engineering judgments toward regulations focused on issues that contribute significantly to safety. Despite the availability of probabilistic risk assessment (PRA) tools, organisations often struggle with how to best use this capability. Most international regulations are still based largely on deterministic analyses that were developed without the benefit of quantitative or measurable estimates of risk. PRA considers issues of risk in a more comprehensive manner by examining a wider spectrum of initiating events and their frequency, and considers the likelihood of events in a rigorous and comprehensive manner. In some countries, nuclear regulators are actively moving toward increasing the use of risk insights in a variety of strategic arenas, including risk-informed technical specifications (operating limits and conditions), in-service inspection and testing, programs, and assessment and enforcement actions. A risk-informed approach enhances the traditional deterministic approach by explicitly considering a broader range of safety challenges, focusing resources on the basis of risk significance, considering a broader range of counter measures to mitigate challenges, and explicitly identifying and quantifying uncertainties in analyses. (author)

  3. Reactor safety through quality assurance and in-service inspection

    International Nuclear Information System (INIS)

    Bush, S.H.

    The quality assurance is discussed of nuclear power plant equipment with respect to the following regulations: section 50 10 CFR - supplement B, section NA-400, ASME - section III and ANSI N-54.2. Quality assurance and reliability are assessed with regard to two aspects: all preoperational functions and all operating stages of the power plant. During the production of nuclear power plant components, increased attention should be devoted to the choice of material, materials testing, production programme and to the production process. During power plant operation, care should be given to periodical in-service inspections which guarantee the plant reliability; defects should immediately be remedied or the power plant shut down. Emphasis is put on the tests of reactor welded joints in compliance with the ASME code. The results of operating tests are used as feedback in the design and testing of the components during production. The probabilities were calculated of the occurrence and elimination of defects during the manufacture and operation of a nuclear reactor. (J.B.)

  4. Crack characterization for in-service inspection planning

    International Nuclear Information System (INIS)

    Waale, J.; Ekstroem, P.

    1995-12-01

    During in-service inspection by non destructive testing the reliability is highly dependent on how the equipment is adjusted to the specific object and to the anticipated crack feature.The crack feature and morphology vary widely between different cracking mechanisms and between material types in which the cracks appear. The major objective of this study was to characterize a number of morphology parameters for common crack mechanism and structure material combinations. Critical morphology parameters are crack orientation, shape, width, surface roughness and branching. The crack parameters were evaluated from failure analyses reported from the nuclear and non-nuclear industry. In addition, a literature review was carried out on crack parameter reports and on failure analysis reports, which were further evaluated. The evaluated crack parameters were plotted and statistically processed in data groups with respect to crack mechanism and material type. The fatigue crack mechanism were classified as mechanical, thermal or corrosion fatigue and stress corrosion crack mechanism as intergranular, transgranular or inter dendritic stress corrosion cracking. Furthermore, some common weld defects were characterized for comparison. The materials were divided into three broad groups, ferritic low alloy steels, stainless steels and nickel base alloys. The results indicate significant differences between crack parameters when comparing data from different crack mechanism/material type combinations. Typical parameter values and scatter were derived for several combinations where the data was sufficient for statistical significance. 10 refs, 105 figs, 14 tabs

  5. Crack characterization for in-service inspection planning

    Energy Technology Data Exchange (ETDEWEB)

    Waale, J [SAQ Inspection Ltd, Stockholm (Sweden); Ekstroem, P [ABB Atom AB, Vaesteraas (Sweden)

    1995-12-01

    During in-service inspection by non destructive testing the reliability is highly dependent on how the equipment is adjusted to the specific object and to the anticipated crack feature.The crack feature and morphology vary widely between different cracking mechanisms and between material types in which the cracks appear. The major objective of this study was to characterize a number of morphology parameters for common crack mechanism and structure material combinations. Critical morphology parameters are crack orientation, shape, width, surface roughness and branching. The crack parameters were evaluated from failure analyses reported from the nuclear and non-nuclear industry. In addition, a literature review was carried out on crack parameter reports and on failure analysis reports, which were further evaluated. The evaluated crack parameters were plotted and statistically processed in data groups with respect to crack mechanism and material type. The fatigue crack mechanism were classified as mechanical, thermal or corrosion fatigue and stress corrosion crack mechanism as intergranular, transgranular or inter dendritic stress corrosion cracking. Furthermore, some common weld defects were characterized for comparison. The materials were divided into three broad groups, ferritic low alloy steels, stainless steels and nickel base alloys. The results indicate significant differences between crack parameters when comparing data from different crack mechanism/material type combinations. Typical parameter values and scatter were derived for several combinations where the data was sufficient for statistical significance. 10 refs, 105 figs, 14 tabs.

  6. Examples of in-service inspections and typical maintenance schedule for low-power research reactors

    International Nuclear Information System (INIS)

    Boeck, H.

    1997-01-01

    In-service inspection methods for low-power research reactors are described which have been developed during the past 37 years of the operation of the TRIGA reactor Vienna. Special tools have been developed during this period and their application for maintenance and in-serve inspection is discussed. Two practical in-service inspections at a TRIGA reactor and at a MTR reactor are presented. Further a typical maintenance plan for a TRIGA reactor is listed in the annex. (author)

  7. A pilot application of risk-informed methods to establish inservice inspection priorities for nuclear components at Surry Unit 1 Nuclear Power Station. Revision 1

    International Nuclear Information System (INIS)

    Vo, T.V.; Phan, H.K.; Gore, B.F.; Simonen, F.A.; Doctor, S.R.

    1997-02-01

    As part of the Nondestructive Evaluation Reliability Program sponsored by the US Nuclear Regulatory Commission, the Pacific Northwest National Laboratory has developed risk-informed approaches for inservice inspection plans of nuclear power plants. This method uses probabilistic risk assessment (PRA) results to identify and prioritize the most risk-important components for inspection. The Surry Nuclear Power Station Unit 1 was selected for pilot application of this methodology. This report, which incorporates more recent plant-specific information and improved risk-informed methodology and tools, is Revision 1 of the earlier report (NUREG/CR-6181). The methodology discussed in the original report is no longer current and a preferred methodology is presented in this Revision. This report, NUREG/CR-6181, Rev. 1, therefore supersedes the earlier NUREG/CR-6181 published in August 1994. The specific systems addressed in this report are the auxiliary feedwater, the low-pressure injection, and the reactor coolant systems. The results provide a risk-informed ranking of components within these systems

  8. Study on In-Service Inspection Program and Inspection Technologies for Commercialized Sodium-Cooled Fast Reactor

    International Nuclear Information System (INIS)

    Masato Ando; Shigenobu Kubo; Yoshio Kamishima; Toru Iitsuka

    2006-01-01

    The objective of in-service inspection of a nuclear power plant is to confirm integrity of function of components necessary to safety, and satisfy the needs to protect plant investment and to achieve high plant ability. The sodium-cooled fast reactor, which is designed in the feasibility study on commercialized fast reactor cycle systems in Japan, has two characteristics related to in-service inspection. The first is that all sodium coolant boundary structures have double-wall system. Continuous monitoring of the sodium coolant boundary structures are adopted for inspection. The second characteristic is the steam generator with double-wall-tubes. Volumetric testing is adopted to make sure that one of the tubes can maintain the boundary function in case of the other tube failure. A rational in-service inspection concept was developed taking these features into account. The inspection technologies were developed to implement in-service inspection plan. The under-sodium viewing system consisted of multi ultrasonic scanning transducers, which was used for imaging under-sodium structures. The under-sodium viewing system was mounted on the under-sodium vehicle and delivered to core internals. The prototype of under-sodium viewing system and vehicle were fabricated and performance tests were carried out under water. The laboratory experiments of volumetric testing for double-wall-tubes of steam generator, such as ultrasonic testing and remote-field eddy current testing, were performed and technical feasibility was assessed. (authors)

  9. Conceptual design of in-service inspection and maintenance for KALIMER

    International Nuclear Information System (INIS)

    Ju, Y. S.; Kim, S. H.; Koo, K. H.; You, B.

    1999-01-01

    In-service inspection and maintenance are very important for the safety and availability of nuclear power plants. The conceptual requirements of in-service inspection and maintenance should be reflected in the earlier design process for the verification of the plant operability and reliability. In this paper the fundamental approaches of the inspection and maintenance for KALIMER are established to ensure the structural integrity and operability for KALIMER. The general strategy and methodology of maintenance and inspection for the reactor system and components are proposed and described for satisfying the intents of the Section XI, Division 3, of ASME code and considering the design characteristics of KALIMER

  10. Scheduling and coordination for in-service inspection of nuclear power plant

    International Nuclear Information System (INIS)

    Li Songbai

    1996-11-01

    Based on the practice and experiences of pre-service and in-service inspections for Daya Bay Nuclear Power Plant (NPP) by Research Institute of Nuclear Power Operation (RINPO) following RSEM code, requirements of utility and actual situation in China, the in-service inspection preparation for organization, techniques and equipment/tooling, materials, personnel and documentation is briefly described. And the scheduling and coordinating consideration for planed in-service inspection activities during NPP outage is emphatically introduced. (2 refs., 4 figs.)

  11. In-service inspections of the reactor cooling system of pressurized water reactors

    International Nuclear Information System (INIS)

    Fuerste, W.; Hohnerlein, G.; Werden, B.

    1982-01-01

    In order to guarantee constant safety of the components of the reactor cooling system, regular in-service inspections are carried out after commissioning of the nuclear power plant. This contribution is concerned with the components of the reactor cooling system, referring to the legal requirements, safety-related purposes and scope of the in-service inspections during the entire period of operation of a nuclear power plant. Reports are made with respect to type, examination intervals, examination technique, results and future development. The functional tests which are carried out within the scope of the in-service inspections are not part of this contribution. (orig.) [de

  12. In-service inspection of nuclear power-plant pressure components

    International Nuclear Information System (INIS)

    Lautzenheiser, C.E.

    1976-01-01

    The early light-water-reactor systems for production of commercial power were designed and fabricated in accordance with the codes then being used for fossil-fired power-generating stations with some design changes for increased inspectability during fabrication. Over the past few years, major strides have been made in in-service inspection technology. Work has been under way to determine the reliability of nondestructive testing methods and to develop formal inspection programs throughout the world. The major problems associated with in-service inspection are the scarcity of qualified personnel, the variability in procedures and data recording between inspection agencies, and exposure of inspection personnel to radiation. Further work will be required to more completely mechanize piping inspections to reduce radiation exposure and to standardize inspection procedures, equipment, and certification of personnel. Worldwide attention to the requirements of the American Society of Mechanical Engineers' Boiler and Pressure Vessel Code, the size and integrity of inspection agencies, and efforts such as the development of personnel qualification and certification guides emphasize the importance of in-service inspection to nuclear safety

  13. Quality control and in-service inspection technology for hybrid-composite girder bridges.

    Science.gov (United States)

    2014-08-01

    This report describes efforts to develop quality control tools and in-service inspection technologies for the fabrication and construction of Hybrid Composite Beams (HCBs). HCBs are a new bridge technology currently being evaluated by the Missouri De...

  14. An overview of in-service inspection for nuclear power plants in Japan

    International Nuclear Information System (INIS)

    Takano, Eishiro

    1996-01-01

    In nuclear power stations, for maintaining the safety of machinery and equipment, it is stipulated to carry out periodic inspection. The contents of the periodic inspection and the inspections of important matters are explained. In-service inspection (ISI) is the nondestructive inspection for confirming the soundness of reactor pressure vessels, main pipings, valves and others. The stipulations on the scope and time of the periodic inspection and ISI, the course of introducing ISI into Japan, and the basic way of thinking on ISI are described. Pre-service inspection (PSI) is carried out for the purpose of collecting and recording the initial data for ISI. The range of the objects of nondestructive inspection and leak test and the range of the objects of leak test only are shown. As to nondestructive inspection, the parts to be inspected, the frequency of inspection and the methods of inspection, and the method of leak test are described. As the present state of inspection technology, the automatic ultrasonic flow detectors for reactor vessels, piping welded parts and reactor vessel stud bolts, and the eddy current flaw detector for steam generator tubes are explained. (K.I.)

  15. Remote controlled ultrasonic pre-service and in-service inspections of reactor pressure vessels

    International Nuclear Information System (INIS)

    Mueller, G.

    1990-01-01

    The first mechanised in-service inspection of the reactor pressure vessel on unit one of Eskom's Koeberg nuclear power station has been carried out. Since 1968 a whole range of manipulators to carry out remote controlled ultrasonic inspections of nuclear power station equipment has been developed. The inspection of a reactor pressure vessel using a central mast manipulator is described. 3 figs., 1 ill

  16. Preventing degradation and in-service inspection of NPP steam generator

    International Nuclear Information System (INIS)

    Ding Xunshen

    1999-01-01

    The author describes the degradation of steam generator tubes in initial operating stage of France NPP. The author emphatically presents the preventive measures to tackle degradation and In-service inspection of Daya Bay NPP 1 unit as a guarantee of safety operation, including secondary side water chemistry monitoring and controlling, leakage rate monitoring, eddy-current inspection, mechanical cleaning, cleanliness inspection, foreign objects removal and etc

  17. New developments in containment in-service inspection requirements

    International Nuclear Information System (INIS)

    Staffiera, J.E.

    1995-01-01

    Section 11 of the ASME Boiler and Pressure Vessel Code contains requirements for inservice inspection of nuclear power plant components. Development of ASME Code requirements for containment inservice inspection was begun in 1977, and in 1979 the first such requirements were published in the form of Code Case N-236. Formal inclusion of these requirements in Section 11 of the ASME Code occurred with publication of Subsection IWE, ''Rules for inservice Inspection of Class MC Components of Nuclear Power Plants,'' in the 1980 Edition, Winter 1981 Addenda. At that time, inspection emphasis on nuclear power construction and operation activities was placed on welds and welding processes associated with steel containments and metallic liners of concrete containments. The need for repair-welding requirements was necessitated by containment design modifications for conditions not considered in several original plant designs. Welds in steel containments and metallic liners of concrete containments have not required significant amounts of repair, however, degradation of base metal in containments has become a major concern. Various degradation mechanisms have been identified as potential causes of damage to containment surfaces, including fatigue, corrosion and material embrittlement due to long-term radiation exposure. As a result of these concerns, and in response to comments generated by the Committee to Review Generic Requirements (CRGR) of the NRC in its review of Subsection IWE, emphasis on weld-based inservice inspection was redirected toward a containment-surface inservice inspection program. Significant changes were made to accommodate this re-emphasis. The majority of these changes were published in the 1992 Edition, with the 1992 Addenda, of Subsection IWE. The NRC Proposed Rulemaking was issued for a 75-day public comment period in January, 1994. This period was extended at the request of nuclear industry organizations to allow for meaningful evaluation

  18. In service inspection for Superphenix vessels development of ultrasonic techniques available at high temperature

    International Nuclear Information System (INIS)

    Gondard, C.

    1983-12-01

    The main and safety vessels of SUPERPHENIX 1 were designed to allow in-service inspections. The remote controlled inspection device MIR was developped for this purpose. The ultrasonic examination has required the development of all new transducers fitted with severe operating conditions prevailing in intervessels interval. A list of problems to be resolved and technological solutions which were found is given. Measurements of acoustical properties on actual probes are compared with theoretical values. It appears that concordance is good and that an in-service inspection using high temperature transducers is possible with a good spatial resolution and signal to noise ratio

  19. Planning and programming of pre-operational and in-service inspections

    International Nuclear Information System (INIS)

    Udaondo, M.S.

    1984-01-01

    After a brief mention of the actual scope of in-service inspection work, conclusions are presented that relate to the preparations for inspections, making use of experience acquired since 1972 at 11 nuclear power plants in Spain which have commissioned such studies from one particular organization, and analyses are given of the advantages to be gained therefrom. Three different aspects of preparations for inspections are considered: (a) man-hour estimates and the duration of in-service inspections; (b) the sequence of action during a pre-operational inspection (assuming a typical functional organization) from definition of the codes of practice and standards applicable up to the issue of the final report and the schedule for distribution of the annual work load to be invested in a typical project, as a result of combining the two previous estimates, and (c) the documentary aspect of preparations for an inspection during a scheduled outage, as related to the various documents to be drawn up and their contents. Reference is made to the general training to be given to the staff in charge of inspection activities so as to provide them with information on, and a perspective of, the in-service inspection jobs required. (author)

  20. Improved in-service inspection program for management of degradation in steam generator tubing

    International Nuclear Information System (INIS)

    Kurtz, R.; Heasler, P.; Muscara, J.

    1992-01-01

    This paper presents an overview of significant results from NRC-sponsored research on steam generator tube integrity and inspection. Burst test results are described along with empirical models to relate flaw geometry and size to tube burst pressure. Results of round robin examinations of a retired-from-service steam generator to determine eddy current inspection reliability are presented. An evaluation and comparison of various sampling plans for in-service inspection of steam generators is discussed. Finally, performance demonstration qualification efforts for eddy current inspection systems are described

  1. Study on in-service inspection methods for the above-ground oil tanks floors

    Energy Technology Data Exchange (ETDEWEB)

    Min Xiong; Yewei Kang; Mingchun, Lin; Yi Sun [PetroChina Pipeline R and D Center, Langfang (China)

    2009-07-01

    It is very dangerous to the environment when oil tank floors get corrosion or leak during its long-time service. The traditional inspection methods need to shut down a tank and to empty it, then to clean it in order to inspect the floor. Comparing with the traditional methods, the in-service methods can inspect tank floors rapidly without removing product and opening the tank and can save many costs of tank emptying and cleaning. This paper explores three up-to date in-service inspection methods for the oil tank floors which are acoustic emission technology ultrasonic guided wave technology and mobile robot technology. The theoretic foundation and application status of each method is described. The advantage and disadvantage of each in-service detection technology is concluded. At last some proposals are made. (author)

  2. In-service inspection program for the NCS-80 reactor pressure vessel

    International Nuclear Information System (INIS)

    Scharge, J.; Wehowsky, P.; Zeibig, H.

    1978-01-01

    The in-service inspection program of reactor pressure vessels is mainly based on the ultra-sonic method, visual checking of inner and outer surfaces as well as pressure and leak tests. The test procedure require a design of the pressure vessel suitable for the test methods and the possibility to remove the pressure vessel internals. For the outside inspection a gap of sufficient width is mandatory. The present status of the ultra-sonic method and of the inner and outer manipulators affords to conduct the in-service inspection program in form of automatic checkings. The in-service inspection program for NCS-80, the Nuclear Container-Ship design of 80,000 shp, is integrated in the refueling periods due to the request for a high availability of the ship and reactor plant

  3. In-service inspection for nuclear power plants

    International Nuclear Information System (INIS)

    1980-01-01

    The Safety Guides are recommendations issued by the Agency for use by Member States in the context of their own nuclear safety requirements. Design consideration, in-service examination, test requirements, repair and replacement, equipment, methods and techniques and also administrative aspects are given in this issue

  4. Demonstration test of in-service inspection methods

    International Nuclear Information System (INIS)

    Takumi, Kenji

    1987-01-01

    The major objectives of the project are: (1) to demonstrate the reliability of a manual ultrasonic flaw detector and techniques that are used in operating light water reactor plants and (2) to demonstrate the performance and reliability of an automatic ultrasonic flaw detector that is designed to shorten the time required for ISI work and reduce the exposure risk of inspection personnel. The test project consists of three stages. In the first stage, which ended in 1982, defects were added intentionally to a model structure the same in size as a typical 1.1 million kW BWR plant and manual ultrasonic flaw detection tensting was performed. In the second stage, completed in 1984, automatic eddy-current flaw detection testing was carried out for defects in heat transfer piping of a PWP steam generator. In the third stage, which started in 1981 and ended in March 1987, a newly developed automatic ultrasonic flaw detector is applied to testing of defects used for the manual detector performance evaluation. Results have shown that the automatic eddy-current flaw detector under test has an adequately stable performance for practical uses, with a very high reproducibility to permit close inspection of secular deterioration in heat transfer pipes. It has also revealed that both the manual and automatic ultrasonic flaw detectors under test can detect all defects that do not comply with the ASME standards. (Nogami, K.)

  5. Advanced In-Service Inspection Approaches Applied to the Phenix Fast Breeder Reactor

    International Nuclear Information System (INIS)

    Guidez, J.; Martin, L.; Dupraz, R.

    2006-01-01

    The safety upgrading of the Phenix plant undertaken between 1994 and 1997 involved a vast inspection programme of the reactor, the external storage drum and the secondary sodium circuits in order to meet the requirements of the defence-in-depth safety approach. The three lines of defence were analysed for every safety related component: demonstration of the quality of design and construction, appropriate in-service inspection and controlling the consequences of an accident. The in-service reactor block inspection programme consisted in controlling the core support structures and the high-temperature elements. Despite the fact that limited consideration had been given to inspection constraints during the design stage of the reactor in the 1960's, as compared to more recent reactor projects such as the European Fast Reactor (EFR), all the core support line elements were able to be inspected. The three following main operations are described: Ultrasonic inspection of the upper hangers of the main vessel, using small transducers able to withstand temperatures of 130 deg. C, Inspection of the conical shell supporting the core dia-grid. A specific ultrasonic method and a special implementation technique were used to control the under sodium structure welds, located up to several meters away from the scan surface. Remote inspection of the hot pool structures, particularly the core cover plug after partial sodium drainage of the reactor vessel. Other inspections are also summarized: control of secondary sodium circuit piping, intermediate heat exchangers, primary sodium pumps, steam generator units and external storage drum. The pool type reactor concept, developed in France since the 1960's, presents several favourable safety and operational features. The feedback from the Phenix plant also shows real potential for in-service inspection. The design of future generation IV sodium fast reactors will benefit from the experience acquired from the Phenix plant. (authors)

  6. Human reliability impact on in-service inspection

    International Nuclear Information System (INIS)

    Spanner, J.C. Sr.

    1986-01-01

    This paper describes a study conducted to identify, characterize, and evaluate the human reliability aspects of ultrasonic testing/inservice inspection (UT/ISI). Recent measurements of UT/ISI system effectiveness have revealed wide variations in performance; suggesting that insufficient emphasis is being placed on the human reliability aspects of nondestructive examination. It appears that NDE performance can be improved through application of the human factors principles relating to the task, training, procedure, environmental, and individual difference variables. These variables are collectively referred to as performance-shaping factors. A man-machine systems model was developed to describe the UT/ISI process using functional task descriptors. The relative operating characteristic (ROC) analysis method, which is derived from signal detection theory, offers unique attributes for analyzing NDT performance. The results of a limited human factors evaluation conducted in conjunction with a mini-round robin test are also described

  7. Steam generator tubes integrity: In-service-inspection

    International Nuclear Information System (INIS)

    Comby, R.J.

    1997-01-01

    The author's approach to tube integrity is in terms of looking for flaws in tubes. The basis for this approach is that no simple rules can be fixed to adopt a universal inspection methodology because of various concepts related to experience, leak acceptance, leak before break approach, etc. Flaw specific management is probably the most reliable approach as a compromise between safety, availability and economic issues. In that case, NDE capabilities have to be in accordance with information required by structural integrity demonstration. The author discusses the types of probes which can be used to search for flaws in addition to the types of flaws which are being sought, with examples of specific analysis experiences. The author also discusses the issue of a reporting level as it relates to avoiding false calls, classifying faults, and allowing for automation in analysis

  8. GIMIS - Integral Solution for the In-Service Inspection Management of Components in NPPs

    International Nuclear Information System (INIS)

    Borovic, Damir; Vukovic, Igor

    2014-01-01

    Performance of in-service testing and inspection of components and systems in nuclear power plants are required in order to maintain the nuclear power plant while in operation and to return the plant to service, following plant outages. GIMIS is comprehensive software that integrates all processes, functions and data related to planning, administrating and executing inspections on systems, structures and components in nuclear power plants. The software is designed as a web application developed using the Microsoft ASP.NET technology, database is a Microsoft SQL, and client is composed of JavaScript frameworks. It can be adapted to local language, regulations, and requirements according to the power plant needs. The application consists of seven interdependent modules, namely: components, equipment, personnel, requirements, inspection planning, inspection execution, and reports. GIMIS deals with component, equipment and personnel management (both internally employed and outsourced), also provides full component history including uploaded documentation, drawings, previous inspection results, and supports various types of requirements. It enables scheduling facilitation using component data and compliance requirements, offers generation of all inspection relevant documentation and reports, and covers the equipment management including calibration requirements, certification of equipment and allocation to specific inspections/outages, as well as personnel certifications and allocation to specific inspections/outages. The paper describes the content and functionality of the GIMIS application and provides information of its built-in capabilities and features. (authors)

  9. Development of Surveillance and In-Service Inspection Programme for Indian Research Reactors Cirus and Dhruva

    International Nuclear Information System (INIS)

    Shukla, D.K.

    2006-01-01

    Many safety requirements for research reactors are quite similar to those of power reactors. For research reactors with a higher hazard potential, the use of safety codes and guides for power reactors is more appropriate. However, there are many important differences between power reactors and research reactors that must be taken into account to ensure that adequate safety margins are available in design and operation of the research reactor. Most research reactors may have small potential for hazard to the public compared to power reactors but may pose a greater potential hazard to the plant operators. The need for greater flexibility in use of research reactors for individual experiments requires a different safety approach. Safety rules for power reactors are required to be substantially modified for application to specific research reactor. Following the intent of the available safety guides for surveillance and In-Service Inspection of Nuclear Power Plants, guidelines were formulated to develop surveillance and In-Service Inspection programme for research reactors Cirus and Dhruva. Based on the specific design of these research reactors, regulatory requirements, the degree of sophistication and experience of the technical organization involved in operating the research reactor, guidelines were evolved for developing and implementing the surveillance and In-Service Inspection programme for research reactors Cirus (40 MWt) and Dhruva (100 MWt) located at Bhabha Atomic Research Centre, Trombay, Mumbai, India. Paper describes the approach adopted for formulation of surveillance and In-service Inspection programme for Dhruva reactor in detail. (author)

  10. ASTRID In Service Inspection and Repair: Review of R&D program and associated results

    International Nuclear Information System (INIS)

    Baqué, François; Jadot, Françoise; Bourdais, Florian le; Sibilo, Julien; Augem, Jean-Michel; Gastaldi, Olivier

    2013-01-01

    In Service Inspection & Repair (ISI&R): → range of provisions enabling to verify that the equipments state is in compliance with design criteria; → other range of provisions allowing to characterize an abnormal situation (failure, operation mistake) and to perform necessary actions to reach again an achievable plant configuration

  11. Super Phenix 1: In-service inspection of main and safety tanks weldments

    International Nuclear Information System (INIS)

    Asty, M.; Vertut, J.; Argous, J.P.

    1980-01-01

    In Service Inspection of the main tank of the Super Phenix 1 reactor is a new demand compared to Phenix: the authorities have asked that surface and internal defects be detected and their evolution monitored in the future. The presence of thermal baffles inside the main tank precludes the access on that side: the distance between the main and safety tanks takes into account the room needed for an In Service Inspection module. An inspection vehicle is presently under development, which includes ultrasonic examination (focussed probes) and visual examination (TV cameras) capabilities. We briefly describe the techniques that have been selected for ultrasonic testing and also for the vehicle and its guidance between the tanks. (author)

  12. Super Phenix 1: In-service inspection of main and safety tanks weldments

    Energy Technology Data Exchange (ETDEWEB)

    Asty, M [DTech/STA, Centre d' Etudes Nucleaires de Saclay (France); Vertut, J [DPR/STEP, Centre d' Etudes Nucleaires de Saclay (France); Argous, J P [DRNR/STRS, Centre d' Etudes Nucleaires de Cadarache (France)

    1980-11-01

    In Service Inspection of the main tank of the Super Phenix 1 reactor is a new demand compared to Phenix: the authorities have asked that surface and internal defects be detected and their evolution monitored in the future. The presence of thermal baffles inside the main tank precludes the access on that side: the distance between the main and safety tanks takes into account the room needed for an In Service Inspection module. An inspection vehicle is presently under development, which includes ultrasonic examination (focussed probes) and visual examination (TV cameras) capabilities. We briefly describe the techniques that have been selected for ultrasonic testing and also for the vehicle and its guidance between the tanks. (author)

  13. Super Phenix 1: in Service inspection of main and safety tanks weldments

    International Nuclear Information System (INIS)

    Asty, Michel; Vertut, Jean; Argous, J.P.

    1980-05-01

    In service inspection of the main tank of the Super Phenix 1 reactor is a new demand as compared to Phenix: the authorities have asked that surface and internal defects could be detected and their evolution monitored in the future. The presence of thermal baffles inside the main tank precludes the access on that side: the distance between the main and safety tanks takes into account the room needed for an In Service Inspection module. An inspection vehicle is presently under development, which includes ultrasonic examination (focussed probes) and visual examination (TV cameras) capabilities. We briefly describe the techniques that have been selected for ultrasonic testing and also for the vehicle and its guidance between the tanks

  14. In-Service Inspection system for coolant channels of Indian PHWRS - evolution and experience

    International Nuclear Information System (INIS)

    Puri, R.K.; Singh, M.

    2006-01-01

    In-Service Inspection (ISI) is the most important of all periodic monitoring and surveillance activities for assuring the structural integrity of coolant channels in the life extension and management of pressurized heavy water reactors (PHWR-CANDU). Indian PHWRs (220 MWe) are characterized by consists by 306 coolant channels in each unit. These channels have to be inspected for various parameters over the operating life of the reactor. ISI of coolant channels necessitated the indigenous development of an inspection system called BARCIS (BARC Channel Inspection System) at Bhabha Atomic Research Center. BARCIS consists of mainly three parts; drive and control unit, special sealing plug and an inspection head carrying various NDT sensors. Five such systems have been built and deployed at various power plants. The paper deals with the development of the BARCIS system for meeting the ISI requirements of coolant channels, development cycle of this system from its conception to evolution to the present state, challenges, data generated and experience gained (ISI of nearly 900 coolant channels has been completed). Prior to BARCIS, pressure tube gauging equipment for pre-service inspection of coolant tubes was developed in 1980. Moreover a tool for ISI of coolant channels in dry condition was developed in 1990. The paper also describes evolution of various contingency procedures and devices developed over the last one decade. Future plans taking into account technological advancement, changes in the scope of inspection due to design and operating experiences and plant layout will also be covered. The paper describes the efforts put in to develop drive and control mechanism to suit the different vault layouts. The drive mechanism is responsible for linear and rotary movement of the inspection head to carry out 100% volumetric inspection. Special emphasis has been laid on the safety devices required during the inspection activity. Special measures for heavy water retention in

  15. Specialists' meeting on in-service inspection and monitoring of LMFBRs. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-11-01

    The purpose of the meeting sponsored by the IAEA on the recommendation of the International Working Group on Fast Reactors (IWGFR) was attended by participants from France, the Federal Republic of Germany, Italy, Japan, the Netherlands, United Kingdom, United States of America, and two international organizations: CEC and IAEA. The purpose of the meeting was to review and discuss inspection requirements and concepts developed in the IWGFR member countries, development of inspection methods and their application in practical work and to recommend future development. The technical sessions were divided into four topical sessions as follows: General Concepts for In-Service Inspection of the Reactor Plant; Remotely Controlled Inspection Systems; Ultrasonic Test Methods; Miscellaneous Test Methods.

  16. Specialists' meeting on in-service inspection and monitoring of LMFBRs. Summary report

    International Nuclear Information System (INIS)

    1980-11-01

    The purpose of the meeting sponsored by the IAEA on the recommendation of the International Working Group on Fast Reactors (IWGFR) was attended by participants from France, the Federal Republic of Germany, Italy, Japan, the Netherlands, United Kingdom, United States of America, and two international organizations: CEC and IAEA. The purpose of the meeting was to review and discuss inspection requirements and concepts developed in the IWGFR member countries, development of inspection methods and their application in practical work and to recommend future development. The technical sessions were divided into four topical sessions as follows: General Concepts for In-Service Inspection of the Reactor Plant; Remotely Controlled Inspection Systems; Ultrasonic Test Methods; Miscellaneous Test Methods

  17. Review of In-Service Inspection and Repair Technique Developments for French Liquid Metal Fast Reactors

    International Nuclear Information System (INIS)

    Baque, F.

    2005-01-01

    In-service monitoring of nuclear plants is indispensable for both the Operator and the Regulator. The notion of in-service monitoring ranges from the continuous monitoring of the reactor in operation to the thorough in-service reactor inspection during programmed shutdowns. However, the highly specific environment found in French liquid metal fast reactor plants - Phenix and Superphenix - makes monitoring and inspection complicated because of the use of a sodium coolant that is hot, opaque, and difficult to drain.The Commissariat a l'Energie Atomique, in collaboration with its traditional French partners, Electricite de France utilities and FRAMATOME/Novatome Engineering, decided to conduct a 6-yr research and development program (1994-2000) to explore this problem vis-a-vis Superphenix, as well as the possibilities of intervening within the reactor block or on components in a sodium environment. Furthermore, the safety reevaluation of Phenix, conducted between 1994 and 2003, represented an excellent 'test bench' during which the limits of inspection processes - applied to an integrated reactor concept - were surpassed using techniques such as fuel subassembly head scanning, ultrasonic examination of the core support, and visual inspection of the cover-gas plenum following a partial sodium draining. Repair techniques were investigated for cleaning of sodium wet structure surfaces, cutting of damaged parts, and welding in sodium aerosol atmosphere. Both conventional and laser processes were tested

  18. MIR: an in-service inspection device for Superphenix 1 vessels

    International Nuclear Information System (INIS)

    Asty, M.; Ceccato, S.; Lerat, B.; Viard, J.

    1986-06-01

    The main and safety vessels of SUPERPHENIX 1 were designed to allow in-service inspections. The remote controlled inspection device MIR was developed for this purpose. It allows both visual and ultrasonic examinations to be performed. Basically, MIR consists of a tetrahedral structure provided with four steering and traction wheels, two for each vessel. A computer assisted control system enables it to be driven to any position on either the main or safety vessels. Operating conditions are briefly reviewed and the main features of MIR presented

  19. Experience on implementing risk-oriented in-service inspection at NPP in USA

    International Nuclear Information System (INIS)

    Grebenyuk, Yu.P.; Zaritskij, N.S.; Kovyrshin, V.G.; Kostenko, S.P.

    2001-01-01

    Experience of implementing risk-oriented in-service inspection (RIISI) of pipelines at the US NPP analyzed. RIISI processes according to the methodologies developed by Westinghouse and EPRI are described and compared. The information is addressed concerning practical matters of RIISI implementing at NPP Beaver Valley and Arkansas Nuclear One. Regulatory activity of the US NRC while implementing NRC at the US NPP. It is shown that using RIISI at NPP is aimed at improvement of examination efficiency, decreasing costs and occupational dose loads while inspecting pipelines

  20. Development of data acquisition and processing system for In-service inspection of nuclear power plants

    International Nuclear Information System (INIS)

    Takama, Shinkichi; Kobayashi, Koji; Satoh, Yoshio; Koga, Yoshihiro; Shimizu, Takakazu

    1981-01-01

    In-service inspection (ISI) is required during the plant outage to assure the reliability of the components of a nuclear power plant. IHI has developed the advanced ISI system which consists of remote controlled and mechanized ultrasonic inspection devices for reactor pressure vessel examination, semi-automatic inspection instruments for piping examination with manual scan and automatic recording, data acquisition and processing system with microprocessor and mini-computer. By this system, ISI can be performed fully satisfying the requirement of ASME Code Sec. XI and minimizing operation in the high radioactive areas. All ultrasonic information is processed by the computer and the examination results such as size and location of ultrasonic indication are printed out in the form of sectional and plan view of the part examined, reproduced screen image and polar plot, etc. as well as the evaluation sheet. This system saves the elaborate work of inspection personnel and is expected to contribute to the improvement of inspection quality and to the reduction of radiation exposure of inspection personnel. (author)

  1. A study on the optimization of test interval for check valves of Ulchin Unit 3 using the risk-informed in-service testing approach

    International Nuclear Information System (INIS)

    Kang, D. I.; Kim, K. Y.; Yang, Z. A.; Ha, J. J.

    2002-01-01

    We optimized the test interval for check valves of Ulchin Unit 3 using the risk-informed in-service testing (IST) approach. First, we categorized the IST check valves for Ulchin Unit 3 according to their contributions to the safety of Ulchin Unit 3. Next, we performed the risk analysis on the relaxation of test interval for check valves identified as relatively low important to the safety of Ulchin Unit 3 to identify the maximum increasable test interval of them. Finally, we estimated the number of tests of IST check valves to be performed due to the changes of test interval. These study results are as follows: The categorization of IST check valve importance; the number of the HSSCs is 24(11.48%), the ISSCs is 40 (19.14%), and the LSSCs is 462(69.38%). The maximum increasable test interval; 6 times of current test interval of ISSCs2 and 40 times of that of LSSCs. The number of tests of IST check valves to be performed during 6 refueling time can be reduced from 7692 to 1333 ( 82.7%)

  2. Applications of risk informed principles at BKAB

    International Nuclear Information System (INIS)

    Ingemarson, I.

    1999-01-01

    BKAB has developed a detailed and useful model for PSA Level 1 that was finished in the beginning of 1999. The PSA-model has already been used in several activities as a tool to form the basis for risk-informed decisions. First of all it is used to reduce the risk that have been identified in the PSA Level 1 but there are plants to use it in justification of criteria in the technical specification, in in-service inspection with focus on the reactor pressure boundary piping and in classifying critical components. (au)

  3. Research and development on in-service inspection system for reactor vessel of FBR's

    International Nuclear Information System (INIS)

    Rindo, Hiroshi; Mitabe, Noriaki; Ara, Kuniaki; Nagai, Keiichi; Otaka, Masahiko

    1993-01-01

    In-Service Inspection (ISI) is required for main components and piping of FBRs. Visual test and volumetric examination of the reactor vessel (RV) from the outer surface are to be performed under severe conditions such as limited space, high temperature and high gamma dose rate during the reactor shutdown. Therefore, ISI should be performed by using a remote operation system, and the ISI system should be very compact. PNC has been developing the ISI system to apply to the RV inspection. Verification and performance tests of ISI system were carried out by use of the RV test model. This paper describes the system structure, system verification tests including operation and controlling the inspection robot, the functions of the visual test and the volumetric examination under the high temperature

  4. Beliefs concerning the reliability of nuclear power plant in-service inspections

    International Nuclear Information System (INIS)

    Kettunen, J.

    1997-01-01

    The aim of the study was to investigate belief systems held by the officials responsible for the planning and supervision of NDT operations within the Finnish nuclear industry. They were asked to express their opinions on (1) the reliability of NDT methods in general, (2) the factors influencing the reliability of in-service inspections, and (3) the degree of reliability of the current inspections operations conducted by means of NDT methods in the Finnish nuclear power plants. Another goal of the study was to assess the adequacy of officials' beliefs (or belief systems). The research data was collected by interviewing representatives from Finnish power companies (Imatran Voima Oy and Teollisuuden Voima Oy), independent inspection organisations, and the Finnish Centre for Radiation and Nuclear Safety (STUK). The adequacy of the beliefs expressed was assessed by means of the results obtained from international NDT reliability studies and on the basis of interviewees' own justification. (refs.)

  5. In-service inspection as an aid to steel pressure vessel reliability

    International Nuclear Information System (INIS)

    Nichols, R.W.

    1975-01-01

    In-service inspection has played an important role in non-nuclear pressure vessel technology, being a legal requirement in many countries. Evidence from surveys of reliability of non-nuclear plant has suggested that such inspections can be effective in reducing the risk of subsequent failures. Recent requirements of the ASME XI code which will be summarised have important implications on the techniques to be used for in-service inspection, and so on design and fabrication aspects. Moreover, in-service inspection can only be an effective procedure if its possible weaknesses are recognised. The first problem is to ensure that an ultrasonic technique is used which is capable of detecting defects of an order of magnitude smaller than the critical size for each particular situation, in whatever defect orientation is important. The potential of different ultrasonic techniques will be compared. Next it is necessary to ensure coverage of all the relevant material. In this respect machine operation is superior to manual scanning, so that manipulation and scanning devices have to be developed. Problems of local geometry and of deviations in geometry have to be discussed with designer and fabricator; plate and clad quality have to be controlled (with respect to surface contour, metallurgical condition and freedom from interfering defects) to ensure inspectability in depth. The reliability of the mechanical and electronic equipment has to be assessed and designed to meet high requirements. Some presentational aids to detection and interpretation will be discussed. Having located a potential defect, the application of fracture mechanics treatments requires knowledge of size, shape and orientation. Some of the problems will be discussed together with possible solutions. (author)

  6. IAEA-RCA training course on in-service inspection of research reactors

    International Nuclear Information System (INIS)

    2002-01-01

    Bhabha Atomic Research Centre (BARC) has acquired a wide range of experience for over four decades in design, construction, operation and maintenance of research reactors. The two-week training course on In-Service Inspection of Research Reactors (ISI) has greatly increased the awareness in the field of ISI of Research Reactors. The training course has been formulated so as to cover most of the topics relevant to ISI of research reactors. Important topics such as rationale for in-service inspection, material degradation mechanisms, non-destructive examination techniques, design evaluation of flaws and radiological, codal and regulatory aspects of ISI for research reactors were covered. Lectures on ISI of elastomeric materials and concrete structures, which are generally used in the construction of reactors have also been included in the course. Papers relevant to INIS are indexed separately

  7. Qualification of NDT systems for in-service inspections of nuclear power plant pressure vessels

    International Nuclear Information System (INIS)

    Elfving, K.

    1998-11-01

    The goal of this study is to determine the requirements of the in-service inspection qualification in Europe, their feasibility in practice and to find out possible manufacture defects in test pieces used in practical trials. The literature study consists of qualification requirements set by European regulatory bodies and by the European nuclear power utilities. Also a brief summary of qualification requirements set by ASME Code, Section XI and comparison between ASME and European qualification requirements is included

  8. Investigation of in service inspection for pressure vessel of the 200 MW nuclear heating reactor

    International Nuclear Information System (INIS)

    He Shuyan; Yin Ming; Liu Junjie; Chang Huanjian; Zhou Ningning

    1997-01-01

    The Nuclear District Heating Reactor (NHR) is a new type of reactor. There are some differences in the arrangement of the primary circuit components and in safety features between NHR and PWR or other reactors. In this paper the safety features of the 200 MW NHR are described. The failure probability, the LBB property and the in-service inspection requirement for the 200 MW NHR pressure vessel are also discussed. (author). 16 refs, 6 figs, 4 tabs

  9. In-service inspection of fertilizer and steel and ship building industries

    International Nuclear Information System (INIS)

    Sanaullah, Md.

    1998-01-01

    There is a good number of fertilizer factories, and steel and ship building industries in Bangladesh. Different NDT methods are being used for in-service inspection of these industries to ensure product reliability, to prevent accident and save human life, to maintain a uniform quality level, to lower manufacturing cost and to minimize the wastage of time and materials and for other benefits. (author)

  10. Investigation of in service inspection for pressure vessel of the 200 MW nuclear heating reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shuyan, He; Ming, Yin; Junjie, Liu; Huanjian, Chang; Ningning, Zhou [Institute of Nuclear Energy and Technology, Tsingua Univ., Beijing (China)

    1997-09-01

    The Nuclear District Heating Reactor (NHR) is a new type of reactor. There are some differences in the arrangement of the primary circuit components and in safety features between NHR and PWR or other reactors. In this paper the safety features of the 200 MW NHR are described. The failure probability, the LBB property and the in-service inspection requirement for the 200 MW NHR pressure vessel are also discussed. (author). 16 refs, 6 figs, 4 tabs.

  11. Qualification of UT methods and systems used for in-service inspections of VVER 440 vessels

    International Nuclear Information System (INIS)

    Skala, Z.; Vit, J.

    2003-01-01

    SKODA JS has been performing automated in-service inspections VVER reactor pressure vessels for more than twenty years. All of these inspections were performed by ultrasonic pulse echo method, combined from 1996 with eddy current testing. The Time of Flight Diffraction Method (TOFD) is one of modern methods of ultrasonic testing. The accuracy of sizing the through wall extent of a flaw by TOFD is much better than the accuracy achievable by the pulse echo method. A series of laboratory tests were performed by SKODA JS and confirmed the suitability of TOFD method for VVER reactor parts testing. The Czech Atomic law demands the qualification of systems and methods used for the in-service inspections of nuclear reactors. The qualification is done in accordance with ENIQ methodology and consists of preparation of the Technical Justification and practical tests made under the surveillance of Qualification Body. SKODA JS intends to qualify systems and methods used for the automated ultrasonic testing of VVER 440 and VVER 1000 reactor components from the inner as well as from the outer surface. The accuracy of the flaw through wall extent sizing by TOFD was confirmed by the qualification of methods and systems used for the testing of VVER 440 vessel circumferential weld and so the TOFD method shall be used routinely by SKODA JS for the inspection of vessel circumferential welds root area and for sizing of flaws exceeding the acceptance level. (author)

  12. Development of in-service inspection system for core support graphite structures in the high temperature engineering test reactor (HTTR)

    Energy Technology Data Exchange (ETDEWEB)

    Sumita, Junya; Hanawa, Satoshi; Kikuchi, Takayuki; Ishihara, Masahiro [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    2003-03-01

    Visual inspection of core support graphite structures using TV camera as in-service inspection and measurement of material characteristics using surveillance test specimens are planned in the High Temperature Engineering Test Reactor (HTTR) to confirm structural integrity of the core support graphite structures. For the visual inspection, in-service inspection system developed from September 1996 to June 1998, and pre-service inspection using the system was carried out. As the result of the pre-service inspection, it was validated that high quality of visual inspection with TV camera can be carried out, and also structural integrity of the core support graphite structures at the initial stage of the HTTR operation was confirmed. (author)

  13. Experience with the WWER-440 MW reactor pressure vessel in-service inspections and evaluation of their results

    International Nuclear Information System (INIS)

    Brumovsky, M.; Kralovec, J.; Prepechal, J.; Sulc, J.

    1989-01-01

    The Power Machinery Plant of Skoda Works in Plzen carries out in-service inspections of WWER-440 MW reactor pressure vessels by means of remote controlled inspection equipment - the TRC reactor test system, and some other inspections devices. The results of the in-service inspections were evaluated by methods based on the fracture mechanics approach, the knowledge of stress and strain distribution, and the operating history of the pressure vessels. Examples of types of defects found and their analysis are shown. (author). 1 tab

  14. Study and discussion on management of nuclear island in-service inspection procedure system in nuclear power plant

    International Nuclear Information System (INIS)

    Zhang Xueliang; Fan Yancheng

    2014-01-01

    In-service inspection of nuclear island is the important way for keeping safety operation of nuclear power plant. Taking Daya Bay Nuclear Power Plant as example, the management problems of in-service inspection system was studied and discussed from the angle of references, contents, classifications etc. Based on comparison with French practice, some points of view on perfection of in-service inspection system and improvement of management ability under future multi-bases and multi-units management mode were presented. (authors)

  15. Study on in-service visual inspection using TV camera for core support graphite components in the HTTR

    International Nuclear Information System (INIS)

    Ishihara, Masahiro; Shibata, Taiju; Kikuchi, Takayuki; Mogi, Haruyoshi

    1999-01-01

    To maintain the structural integrity of graphite components during plant operation a visual inspection using a TV camera as an in-service inspection is planned in the High Temperature Engineering Test Reactor. In order to verify the in-service inspection method a preliminary analytical and experimental studies were performed. In the analytical study the harmful flaw size was determined from a viewpoint of structural integrity based on the fracture mechanics approach. Furthermore, the visible flaw size was determined by the TV camera performance test with graphite test specimens having several kinds of artificial flaws. This paper presents the analytical result on the harmful flaw size and the experimental result on the visible flaw size. From both results the applicability on the visual inspection by the TV camera as the in-service inspection is discussed in this paper. (author)

  16. Nuclear containment systems and in-service inspection status of Korea nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Jihong, Park; Jaekeun, Hong; Banuk, Park [Korea Institute of Machinery and Materials, Dept. of Authorized Test and Evaluation, Kyungnam (Korea, Republic of)

    2007-07-01

    20 unit nuclear power plants in Korea have been operated and maintained since the first unit started in commercial service in 1978. Most recently 4 units were under construction and several units were planned to be constructed. by industries. 4 types of nuclear containment systems have been constructed until now: first, metal containments, then pre-stressed concrete containments with grouted tendon systems, followed by pre-stressed concrete containments with un-grouted tendon systems, and Korea standard nuclear containments. All the nuclear containments should be inspected periodically. Therefore for periodic in-service inspection, several appropriate technical requirements should be applied differently depending on the specific nuclear containment types. With the changes of times, nuclear containment systems have undergone a remarkable change, and finally nuclear containment system of Korea standard nuclear power plant was settled down, and as a matter of course it dominates the trend of present and future nuclear containment systems. Overall in-service inspection results of most Korea nuclear containments have not showed any serious evidence of degradation.

  17. Conceptual design and assessment of in-service inspection and maintenance of KALIMER

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Kim, Seok Hun; Kim, Jong Bum; Lee, Jae Han [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-05-01

    In the conceptual design stage of KALIMER, the philosophy and methodology of in-service inspection (ISI) and maintenance for the reactor system and components are proposed and described. The ISI and maintenance should be carried out throughout plant life to ensure the structural integrity and safety of KALIMER. The conceptual design of ISI and maintenance are performed for considering the design characteristics of KALIMER and the intents of the ASME XI Division 3. This report describes and summarizes the requirements and available methods of ISI and maintenance. The visual inspection and continuous monitoring play a great role in the in-service inspection of KALIMER. The major structures of KALIMER reactor system are designed for maintenance free operation for the plant life time and the maintenance philosophy is to replace major components rather than repair them. The assessment of the ISI accessibility and maintainability is performed and reviewed each major component. The postulated failure defects for each component are estimated and evaluated for KALIMER safety and reliability. 8 refs., 16 figs., 13 tabs. (Author)

  18. In-service inspection of ET-RR-1 reactor vessels and spent fuel storage tank

    International Nuclear Information System (INIS)

    Khattab, M.; Shafy, M.; Konoplev, K.; Samodurve, YU.; Orlov, S.; Didenko, V.; Jackorev, O.

    1993-01-01

    Technical survey included in-service inspection are needed in order to investigate the structural integrity and to insure safe operation of the ET-R R-1 reactor after thirty years aging. An intensive work for the inspection of the inspection of the central tank, shield tank, horizontal channels, primary coolant circuit and spent fuel storage tank have been carried out. The inspection procedures were visual method using video camera and magnification optical as well as thickness measurements using ultrasonic gauge meter and replica for determining defect depth. Water chemical analysis of the primary cooling circuit and spent fuel storage were helpful in results explanation. The results showed that the reactor vessels have good surface conditions. The observed pitting did not affect the structural integrity. The majority of the defects were pits having maximum surface area of about 50 mm. Their depth does not exceed 2 mm. The pits depth rate penetration is of the order of 0.5% per year. Thickness measurements showed insignificant variation. Water status and its chemical properties are very important in controlling corrosion rate. 18 figs., 14 tabs

  19. Automation and mechanization of in-service inspection of selected equipment in FRG's nuclear power plants

    International Nuclear Information System (INIS)

    Metke, E.

    1988-01-01

    The procedures and equipment are described for the automation and mechanization of in-service inspection in nuclear power plants in the FRG, used by the KWU company. Checks of the pressure vessel are done by visual means using a colour tv camera, the method of eddy currents and the ultrasonic method. An analysis is made of the time schedule of ultrasonic inspections, and the central column manipulator is described which allows to check all internal regions of the pressure vessel. Attention is also devoted to other devices, e.g., those for prestressing shanks, cleaning shanks, cleaning thread apertures, etc. A combined probe using the ultrasonic method and the eddy current method serves the inspection of heat exchange tubes in the steam generator. For inspecting the primary circuit the KWU company uses devices for checking and working the inner surface of pipes. Briefly described are examples of using KWU equipment in nuclear power plants in CMEA countries. (Z.M.). 11 figs., 6 refs

  20. Development of a risk-based in-service inspection program for an LMR

    International Nuclear Information System (INIS)

    King, R.W.; Buschman, H.W.

    1996-01-01

    The emerging application of risk-based assessment technology to the operation and maintenance of nuclear power plants holds considerable promise for improving efficiency and reducing operating costs. Experimental Breeder Reactor II (EBR-II) is a liquid-metal-cooled fast reactor (LMR) that operated for 30 yr before shutting down in September 1994 due to program termination. Prior to the shutdown of EBR-II, an in-service inspection (ISI) program was developed that exploited certain advantages of the LMR design. For example, it demonstrated passive response to plant upset events, low-pressure primary coolant, and compatibility of the coolant and reactor materials. This ISI program was based on work currently being done by an American Society of Mechanical Engineers (ASME) Research Task Force on Risk-Based Inspection

  1. Automatic ultrasonic testing and the LOFT in-service inspection program

    International Nuclear Information System (INIS)

    Hunter, J.A.

    1980-01-01

    An automatic ultrasonic testing system has been developed which significantly improves the flaw indication detection and characterization capability over the capability of conventional volumetric examination techniques. The system utilizes an accurately located ultrasonic sensor to generate the examination data. A small computer performs and integrates control and data input/output functions. Computer software has been developed to provide a rigorous method for data analysis and ultrasonic image interpretation. The system has been used as part of an in-service inspection program to examine welds in thich austenitic stainless steel pipes in a small experimental nuclear reactor

  2. The influence of frequency and reliability of in-service inspection on reactor pressure vessel disruptive failure probability

    International Nuclear Information System (INIS)

    Jordan, G.M.

    1978-01-01

    A simple probabilistic methodology is used to investigate the benefit, in terms of reduction of disruptive failure probability, which comes from the application of periodic in-service inspection to nuclear pressure vessels. The analysis indicates the strong interaction between inspection benefit and the intrinsic quality of the structure. In order to quantify the inspection benefit, assumptions are made which allow the quality to be characterised in terms of the parameters governing a log normal distribution of time - to - failure. Using these assumptions, it is shown that the overall benefit of in-service inspection unlikely to exceed an order of magnitude in terms of reduction of disruptive failure probability. The method is extended to evaluate the effect of the periodicity and reliability of the inspection process itself. (author)

  3. Statistical Sampling For In-Service Inspection Of Liquid Waste Tanks At The Savannah River Site

    International Nuclear Information System (INIS)

    Harris, S.

    2011-01-01

    Savannah River Remediation, LLC (SRR) is implementing a statistical sampling strategy for In-Service Inspection (ISI) of Liquid Waste (LW) Tanks at the United States Department of Energy's Savannah River Site (SRS) in Aiken, South Carolina. As a component of SRS's corrosion control program, the ISI program assesses tank wall structural integrity through the use of ultrasonic testing (UT). The statistical strategy for ISI is based on the random sampling of a number of vertically oriented unit areas, called strips, within each tank. The number of strips to inspect was determined so as to attain, over time, a high probability of observing at least one of the worst 5% in terms of pitting and corrosion across all tanks. The probability estimation to determine the number of strips to inspect was performed using the hypergeometric distribution. Statistical tolerance limits for pit depth and corrosion rates were calculated by fitting the lognormal distribution to the data. In addition to the strip sampling strategy, a single strip within each tank was identified to serve as the baseline for a longitudinal assessment of the tank safe operational life. The statistical sampling strategy enables the ISI program to develop individual profiles of LW tank wall structural integrity that collectively provide a high confidence in their safety and integrity over operational lifetimes.

  4. ASME section XI - design and access requirements for in-service inspection

    International Nuclear Information System (INIS)

    Davis, D.D.

    1982-01-01

    The Owner of a nuclear power plant has the regulatory commitment to perform Section XI in-service inspection throughout the service life of a plant. In anticipation of what will be needed to perform adequately the required examinations and tests, sub-article IWA-1500 of Section XI not only requires that sufficient access be provided to accommodate equipment and inspection personnel but also requires that other provisions be considered such as: component surface preparations, material selections, shielding, removal and storage of hardware, handling equipment, and provisions for repairs and replacements. It is, therefore, the owner's and the architect engineer's responsibility to ensure that proper design and access provisions are incorporated to enable the owner to meet his commitments. Since the architect engineer usually has the prime responsibility for the implementation of design criteria, the owner must ensure that these provisions be considered in each phase of design and construction. The benefits of this can result in shorter outages, more meaningful examinations and tests and less radiation exposure of inspection personnel. This paper will address in detail those topics that affect design and access provisions which need to be considered during the design and construction of a nuclear power plant. (author)

  5. The ASME research task force on risk-based in-service inspection

    International Nuclear Information System (INIS)

    Balkey, K.R.; Chapman, O.J.V.

    1997-01-01

    The use of risk-based methods in the development of in-service inspection (ISI) and in-service testing (IST) programs for nuclear power plant and other industrial applications has been studied for the last several years through the American Society of Mechanical Engineers Centre for Research and Technology Development (ASME 1991, 1992, 1994, 1996). The results of this work are being used as a foundation to develop specific requirements for implementation of risk-based technology in ASME Codes and Standards, regulatory requirements and industry programs both in the U.S. and other countries. This paper provides a brief overview of the ASME Research Methodology and how it has been adapted for application to the inspection of piping within the USA. It also relates how the reliability of nondestructive examination (NDE) methods for pressure boundary components can impact the risk and discusses the relationship between this and NDE qualification/demonstration now being implemented in Europe and the USA. (orig.)

  6. RSE-M: In-Service Inspection Rules for Mechanical Components of PWR Nuclear Islands

    International Nuclear Information System (INIS)

    2016-01-01

    The RSE-M code defines in-service inspection operations. It applies to pressure equipment used in PWR plants, as well as spare parts for such equipment. The RSE-M code does not apply to equipment made from materials other than metal. It is based on the RCC-M code for requirements relating to the design and fabrication of mechanical components. Use: The inspection rules specified in the RSE-M code describe the standard requirements of best practice within the French nuclear industry, based on its own feedback from operating several nuclear units and partly supplemented with requirements stipulated by French regulations. To date, the 58 units in France's nuclear infrastructure enforce the in-service inspection rules of the RSE-M code. Operation of 30 commissioned units in China's nuclear infrastructure, corresponding to the M310, CPR-1000 and CPR-600 reactors, is based on the RSE-M code (since 2007, use of AFCEN codes has been required by NNSA for Generation II+ reactors). Contents of the 2016 Edition: Volume I - Rules: Section A - General rules, Section B - Specific rules for class 1 components, Section C - Specific rules for class 2 or 3 components, Section D - Specific rules for components not assigned to any particular RSE-M class; Volume II - Appendices 1 to 8: Appendices 1.0 to 1.9: supporting appendices for the general requirements, Appendix 2.1: appendix associated with chap. 2000 Requalifications, Hydraulic Proof Tests and Hydraulic Tests, Appendices 4.1 to 4.4: appendices associated with chap. 4000 Examination techniques, Appendices 5.1 to 5.8 and RPP2: appendices associated with chap. 5000 Mechanical and Materials, Appendices 8.1 to 8.2: appendices associated with chap. 8000 Maintenance Operations; Volume III: Appendix 3.1 - Visit tables: main primary and secondary systems, EPR pre-service inspection program, Class 2 or 3 vessels; Appendix 3.2 - Inspection Plans For Non-Nuclear Pressure Equipment

  7. Report on the Regulators Experience of NDT Qualification for In-service Inspection of Nuclear Components

    International Nuclear Information System (INIS)

    2003-08-01

    In November 1992, the Nuclear Regulators Working Group (NRWG) decided to set up a task force on qualification of non-destructive testing (NDT) systems for pre and in-service inspection of light water reactors. The first task was to agree on the philosophy and principles governing the qualification of techniques, equipment, software, procedures, and personnel for NDT to be used for the inspection of structural components that are important to safety in nuclear power plants; and to establish a common view on essential aspects of NDT qualifications. The first task, which also included a comparison of the common views of the European regulators with the qualification approach outlined in Appendix VIII to Section XI of the ASME Code, was completed in 1996. The result was published in the report ''Common position of European regulators on qualification of NDT systems for pre- and in-service inspection of light water reactor components''2. In parallel, the European nuclear power industries had set up a working group, the European Network for Inspection Qualification (ENIQ), to discuss and agree on how to perform inspection qualifications. In 1995, ENIQ finalized its first version of ''European methodology for qualification of non-destructive tests''3. A second version 4 was then published in 1997. This second version is in relatively close agreement with the principles given in the regulators common position document. With these two basic documents, a platform was established for the further development of qualification strategies in the European countries. The second task of the NRWG Task Force was to follow and evaluate the first ENIQ pilot study from a regulatory point of view. The objective of this pilot study was to explore ways of how to apply the European qualification methodology and to test its feasibility. The pilot study commenced late 1996 and was planned to be finalized a year later. Depending on unforeseen difficulties, the pilot study has been delayed

  8. Maintenance, surveillance and in-service inspection in nuclear power plants. Safety guide

    International Nuclear Information System (INIS)

    2002-01-01

    Effective maintenance, surveillance and in-service inspection (MS and I) are essential for the safe operation of a nuclear power plant. The objective of this Safety Guide is to provide recommendations and guidance for MS and I activities to ensure that SSCs important to safety are available to perform their functions in accordance with the assumptions and intent of the design. This Safety Guide covers the organizational and procedural aspects of MS and I. However, it does not give detailed technical advice in relation to particular items of plant equipment, nor does it cover inspections made for and/or by the regulatory body. This Safety Guide provides recommendations and guidance for preventive and remedial measures, including testing, surveillance and in-service inspection, that are necessary to ensure that all plant structures, systems and components (SSCs) important to safety are capable of performing as intended. This Safety Guide covers measures for fulfilling the organizational and administrative requirements for: establishing and implementing schedules for preventive and predictive maintenance, repairing defective plant items, selecting and training personnel, providing related facilities and equipment, procuring stores and spare parts, and generating, collecting and retaining maintenance records for establishing and implementing an adequate feedback system for information on maintenance. MS and I should be subject to quality assurance in relation to all aspects important to safety. Quality assurance has been dealt with in detail in other IAEA safety standards and is covered here only in specific instances, for emphasis. In Section 2, a concept of MS and I is presented and the interrelationship between maintenance, surveillance and inspection is discussed. Section 3 concerns the functions and responsibilities of different organizations involved in MS and I activities. Section 4 provides recommendations and guidance on such organizational aspects as

  9. Maintenance, surveillance and in-service inspection in nuclear power plants. Safety guide

    International Nuclear Information System (INIS)

    2005-01-01

    Effective maintenance, surveillance and in-service inspection (MS and I) are essential for the safe operation of a nuclear power plant. The objective of this Safety Guide is to provide recommendations and guidance for MS and I activities to ensure that SSCs important to safety are available to perform their functions in accordance with the assumptions and intent of the design. This Safety Guide covers the organizational and procedural aspects of MS and I. However, it does not give detailed technical advice in relation to particular items of plant equipment, nor does it cover inspections made for and/or by the regulatory body. This Safety Guide provides recommendations and guidance for preventive and remedial measures, including testing, surveillance and in-service inspection, that are necessary to ensure that all plant structures, systems and components (SSCs) important to safety are capable of performing as intended. This Safety Guide covers measures for fulfilling the organizational and administrative requirements for: establishing and implementing schedules for preventive and predictive maintenance, repairing defective plant items, selecting and training personnel, providing related facilities and equipment, procuring stores and spare parts, and generating, collecting and retaining maintenance records for establishing and implementing an adequate feedback system for information on maintenance. MS and I should be subject to quality assurance in relation to all aspects important to safety. Quality assurance has been dealt with in detail in other IAEA safety standards and is covered here only in specific instances, for emphasis. In Section 2, a concept of MS and I is presented and the interrelationship between maintenance, surveillance and inspection is discussed. Section 3 concerns the functions and responsibilities of different organizations involved in MS and I activities. Section 4 provides recommendations and guidance on such organizational aspects as

  10. In-service inspection and maintenance schedule for a typical TRIGA Mark-II reactor

    International Nuclear Information System (INIS)

    Boeck, H.

    1996-05-01

    This report lists all the systems and components of the TRIGA reactor Vienna which are inspected and maintained in regular intervals. These intervals are categorized in monthly, quarterly, semi-annual and annual inspections. Further the type of inspection and the responsibility for the inspection is shown. For each component specific inspection sheets have been developed, some examples are given in the annex. (author)

  11. In-service Inspection of Radioactive Waste Tanks at the Savannah River Site – 15410

    Energy Technology Data Exchange (ETDEWEB)

    Wiersma, Bruce [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Maryak, Matthew [Savannah River Remediation, LLC., Aiken, SC (United States); Baxter, Lindsay [Univ. of Notre Dame, IN (United States); Harris, Stephen [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Elder, James [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-01-12

    Liquid radioactive wastes from the Savannah River Site (SRS) separation process are stored in large underground carbon steel tanks. The high level wastes are processed in several of the tanks and then transferred by piping to other site facilities for further processing before they are stabilized in a vitrified or grout waste form. Based on waste removal and processing schedules, many of the tanks will be required to be in service for times exceeding the initial intended life. Until the waste is removed from storage, transferred, and processed, the materials and structures of the tanks must maintain a confinement function by providing a barrier to the environment and by maintaining acceptable structural stability during design basis events, which include loadings from both normal service and abnormal (e.g., earthquake) conditions. A structural integrity program is in place to maintain the structural and leak integrity functions of these waste tanks throughout their intended service life. In-service inspection (ISI) is an essential element of a comprehensive structural integrity program for the waste tanks at the Savannah River Site (SRS). The ISI program was developed to determine the degree of degradation the waste tanks have experienced due to service conditions. As a result of the inspections, an assessment can be made of the effectiveness of corrosion controls for the waste chemistry, which precludes accelerated localized and general corrosion of the waste tanks. Ultrasonic inspections (UT) are performed to detect and quantify the degree of general wall thinning, pitting and cracking as a measure of tank degradation. The results from these inspections through 2013, for the 27 Type III/IIIA tanks, indicate no reportable in-service corrosion degradation in the primary tank (i.e., general, pitting, or cracking). The average wall thickness for all tanks remains above the manufactured nominal thickness minus 0.25 millimeter and the largest pit identified is

  12. Automation of eddy current system for in-service inspection of turbine and generator rotor bores

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    The current project (EPRI-RP-1975-5) is a continuation of activities that began several years ago. Those results (EPRI-RP-1957-1) indicated that eddy current testing shows promise for in-service inspection. The current project investigates the degree to which eddy current testing can be used to replace bore magnetic particle testing. For this purpose, correlation studies between eddy current and magnetic particle tests are being undertaken on laboratory rotor sections and field test pieces of rotors. The eddy current data are to be gathered automatically by a combination of the Nortec-25L Eddyscope (to provide the analog eddy current signals) and the General Electric DATAQ/sup TM/ (a registered trademark of the General Electric Co.) System (to perform the automatic data acquisition). This paper describes some test results on a flaked laboratory rotor section

  13. Ultrasonic wall thickness gauging for ferritic steam generator tubing as an in-service inspection tool

    International Nuclear Information System (INIS)

    Haesen, W.M.J.; Tromp, Th.J.

    1980-01-01

    In-service inspection of LWR steam generators is more or less a standard routine operation. The situation can be very different for LMFBRs. For the SNR 300 (Kalkar Power Station) the situation is different because the steam generators have ferritic tubing. The tube walls are comparatively thick, 2 to 4.5 mm. During inservice examinations the steam generators will be drained on both sides, however on the sodium side a sodium film will be present. Furthermore the SNR 300 will have two types of steam generator. A straight tube design and a helical coil design will be used. Both types consist of a evaporator and superheater. The steam generators are of course not radioactive. It is obvious that in this case the eddy current (EC) technique is not an enviable inservice inspection tool. Basically EC is a surface flaw detection technique. Only the saturation magnetisation method will improve the EC technique sufficiently for ferritic material. However the 'in bore examination' with the saturation technique was, in case of the SNR 300 steam generator tubing, considered impossible since the inner diameters are fairly small. Furthermore sodium traces may influence the EC method. Although multifrequency methods can solve this problem, EC is not considered as a useful tool for examining ferritic tubing. Another method is to employ the 'stray flux' method which is under development with the TNO organization in Holland. The EC and stray flux method do have one drawback, these methods do not detect gradual changes in wall thickness. Ultrasonic examinations will be used in the SNR 300 as the main inspection tool for the steam generators. In this paper the reasons why ultrasonic examination was selected are explained. The results of the development work on this subject are discussed

  14. An automated eddy current in-service inspection system for nuclear steam generator tubing

    International Nuclear Information System (INIS)

    Wells, N.S.

    1981-06-01

    A prototype steam generator in-service inspection system incorporating remotely-controlled instrumentation linked by a digital transmission line to an instrument and control trailer outside the reactor containment has been designed and manufactured and is presently undergoing field tests. The (Monel 400) steam generator tubes are scanned two at a time using absolute eddy current probes controlled by two remotely-operated probe drives at a scanning speed of 0.5 m/s. The probes are positioned on the tubesheet by a light-weight (1.5 kg) microprocessor-operated tubesheet walker mechanism. Digitized control and data signals are transmitted up to 300 m to the control trailer. There the control and analysis computers extract the relevant signal information and present it in condensed form as labelled graphics on CRT consoles for on-line visual assessment. Hard copy output is also provided for each tube scanned (one per minute). Condensed data is archived on magnetic tapes for additional off-line analysis and comparisons with other inspections

  15. French codes and standards for design, construction and in-service inspection of nuclear power plants

    International Nuclear Information System (INIS)

    Hugot, G.; Grandemange, J. M.

    1995-01-01

    In 1970, France decided that its future power plants would be of the Pressurized Water Reactor type. This choice proved to be successful since it resulted in more than 60 PWR units in operation or under construction in France and abroad. At the beginning of such a program, the French engineering and manufacturing industry, the national electrical utility and the Safety Authorities had to face the many challenges imposed by the implementation of an imported technology. The government reorganised the licensing process. FRAMATOME, the NSSS vendor, and EDF (Electricite de France), the national utility, decided to create 'AFCEN', the French Association for Design and Construction Rules for Nuclear Island Components. These rules, the RCC's (Regles de Construction et de conception), which are approved by French Safety Authorities deal with mechanical and electrical equipment as well as with nuclear fuel and civil works. They are now being supplemented by in service inspection rules, the RSE's (Regles d'inspection en Service). The paper presents these Codes and their main updating following experience of application, technical progress and evolution of standards. Status of discussion concerning reference to European standardisation and developments of rules applicable to the EPR project will also be discussed

  16. Nuclear reactor capable of electric power generation during in-service inspection

    International Nuclear Information System (INIS)

    Nakamura, Shinsuke; Nogami, Hitoshi.

    1992-01-01

    The nuclear power plant according to the present invention can generate electric power even in a period when one of a pair of reactors is put to in-service inspection. That is, the nuclear power plant of the present invention comprises a system constitution of two nuclear reactors each of 50% thermal power and one turbine power generator of 100% electric power. Further, facilities of various systems relevant to the two reactors each of 50% thermal power, as a pair, are used in common as much as possible in order to reduce the cost for construction and maintenance/ inspection. Further, a reactor building and a turbine building disposed in adjacent with each for paired two reactors each of 50% thermal power are arranged vertically. This arrangement can facilitate the common use of the facilities for various systems and equipments to attain branching and joining of fluids in reactor feed water systems and main steam system pipelines easily with low pressure loss and low impact shocks. The facility utilization factor of such reactors is remarkably improved by doubling the period of continuous power generation. As a result, economic property is remarkably improved. (I.S.)

  17. Activities with regard to research and development of technics for SNR 300 reactor vessel in-service inspection procedures

    International Nuclear Information System (INIS)

    Hoeller, K.; Kirchner, G.; Menck, J.

    1980-01-01

    During the development of SNR 300 in-service inspection equipment, several branches were tested by experiment. In this report special steps for testing of manipulation systems and additional engineering equipment for control systems, such as coupling fluid circuit or camera cooling system are considered more in detail

  18. Development of in-service inspection plans for nuclear components at the Surry 1 nuclear power station

    International Nuclear Information System (INIS)

    Vo, T.V.; Simonen, F.A.; Doctor, S.R.; Smith, B.W.; Gore, B.F.

    1993-01-01

    As part of the nondestructive evaluation reliability program sponsored by the US Nuclear Regulatory Commission at Pacific Northwest Laboratory, a methodology has been developed for establishing in-service inspection priorities of nuclear power plant components. The method uses results of probabilistic risk assessment in conjunction with the techniques of failure modes and effects analysis to identify and prioritize the most risk-important systems and components for inspection at nuclear power plants. Surry nuclear power station unit 1 was selected for demonstrating the methodology. The specific systems selected for analysis were the reactor pressure vessel, the reactor coolant, the low pressure injection including the accumulators, and the auxiliary feedwater. The results provide a risk-based ranking of components that can be used to establish a prioritization of the components and a basis for developing improved in-service inspection plans at nuclear power plants

  19. The influence of frequency and reliability of in-service inspection on reactor pressure vessel disruptive failure probability

    International Nuclear Information System (INIS)

    Jordan, G.M.

    1977-01-01

    A simple probabilistic methodology is used to investigate the benefit, in terms of reduction of disruptive failure probability, which comes from the application of periodic In Service Inspection (ISI) to nuclear pressure vessels. The analysis indicates the strong interaction between inspection benefit and the intrinsic quality of the structure. In order to quantify the inspection benefit, assumptions are made which allow the quality to be characterized in terms of the parameters governing a Log Normal distribution of time-to-failure. Using these assumptions, it is shown that the overall benefit of ISI is unlikely to exceed an order of magnitude in terms of reduction of disruptive failure probability. The method is extended to evaluate the effect of the periodicity and reliability of the inspection process itself. (author)

  20. In service inspection of pipes based on risk methods; Inspeccion en servicio de tuberias basada en metodos de riesgo

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza G, G.; Viais J, J.; Carmona C, M. [ININ, Centro Nuclear ' Dr. Nabor Carrillo Flores' , Carretera Mexico Toluca, S/N. La Marquesa, Ocoyoacac, Mexico, C. P. 52750 (Mexico)]. e-mail: gmg@nuclear.inin.mx

    2006-07-01

    The politics of the Nuclear Regulatory Commission (by its initials in English NRC) of the United States of America on the use of the Probabilistic Safety Analysis (PSA) in activities of nuclear regulation it foments the use of this analysis technique to improve the decisions making, to reduce the unnecessary work in maintenance aspects, inspection and tests and to improve the regulatory efficiency. The inspection programs in service (ISI by its initials in English) developed by the American Society of Mechanical Engineers (by its initials in English ASME) it has been the one primary mechanism to prove the mechanical equipment in plants of nuclear energy, these programs indeed have been carried out in plants of nuclear energy by more of two decades. Their purpose is to identify the conditions, such as indications of cracks that are precursory of flights and ruptures which violate the integrity principles of the pressure frontier. The inspection in service activities include ultrasonic tests, surface tests and penetrating liquids test, also activities that include the scaffolds construction, removal of insulations and welding polishing. The inspections in service every 18 months during the times outside of service are executed. One of the objectives is to lower the costs of the inspections during the times outside of service and to reduce the exposure to the radiation by part of the personnel during these times out for inspections, while it is increased or it maintains the personnel's safety and the reliability. As part of the methodology a pipe segment is selected for which a fault in any point has the same consequences, being calculated the fault probability of the tube using the dimensions of the segment. In this work the inspection in service methodology is applied based on risk to an aspersion system of low pressure of the Laguna Verde Nucleo electric Central. For this system a reduction in the number of welding to inspect of 103 to only 15 is obtained

  1. In-service inspection of electronics components, circuits and nuclear radiation detectors

    International Nuclear Information System (INIS)

    Darbhe, M.D.

    2002-01-01

    A nuclear reactor is a complex process plant. Like a nuclear power plant, the research reactors also employ various nuclear and process systems, the scope and number of such systems being plant-specific. In-service inspection of these systems is an important requirement and is applied at various levels of their constituent units such as detectors, electronics components, circuits and integrated systems. The sensors used cover a wide range such as neutronic, radiation, process (pressure, temperature, flow, level) and many others. The present discussion is limited to neutronic and radiation detectors. The electronic components used normally consist of passive components like resistors, capacitors, semiconductor components like diodes, transistors, analog integrated circuits and digital integrated circuits and electromagnetic relays, to name a few. In order to have a comprehensive surveillance and ISI plan, over the entire plant life, it is necessary to understand various mechanisms, which degrade the performance of these systems. These are discussed initially and later various ISI methods that are used on component-circuit or system level, to ensure optimum system performance, are discussed. The computerised systems, because of hardware and software considerations, have to be given special attention, and the same are discussed briefly

  2. The operator's requirement for in service inspection at Hinkley Point 'B' power station

    International Nuclear Information System (INIS)

    Outram, J.F.

    The subject is discussed under the following heads: the need for reactor internal inspection (safety; commercial interest); the methods available (man access inspection; remote viewing inspection); experience with man access; experience with remote viewing; reactor outage time -comparison of the two methods; contamination control; conclusions. (U.K.)

  3. State-of-practice review of ultrasonic in-service inspection of Class I system piping in commercial nuclear power plants

    International Nuclear Information System (INIS)

    Morris, C.J.; Becker, F.L.

    1982-08-01

    The Pacific Northwest Laboratory conducted a survey to determine the state of practice of ultrasonic in-service inspection of primary system piping in light water reactors. Personnel at four utilities, five inspection organizations, and three domestic reactor manufacturers were interviewed. The intention of the study was to provide a better understanding of the actual practices employed in in-service inspection of primary system piping and of the difficulties encountered

  4. Development of In-Service Inspection system for heat transfer tubes in the primary pressurized water cooler in the HTTR

    Energy Technology Data Exchange (ETDEWEB)

    Shinozaki, Masayuki; Furusawa, Takayuki [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Wada, Shigeyuki

    1999-08-01

    The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)

  5. Fuel channel in-service inspection programs program design for maximum cost effectiveness

    International Nuclear Information System (INIS)

    Van den Brekel, N.C.

    1995-01-01

    Inspection is an integral part of fuel channel life management strategy. Inspection data is used to assess the state of reactor core integrity and provide the information necessary to optimize long term maintenance programs. This paper will provide an overview of the structured approach to developing fuel channel inspection programs within OHN. The inspection programs are designed to balance the resources utilized (cost, outage time, and dose expenditure) with the benefits provided by the inspection data obtained (improved knowledge of component status, degradation mechanisms and rates, etc..). The CANDU community has yet to have a fuel channel operate for a full 30 year design life. Since research programs can not fully simulate reactor operating conditions, inspections become an essential feature of the life management strategy as the components age. Inspection programs often include activities designed to develop predictive capability for long term fuel channel behaviour and provide early warning of changes in behaviour. It should be noted that although this paper addresses the design of fuel channel inspection programs, the basic principles presented can be applied to the design of inspection programs for any major power plant component or system. (author)

  6. Design considerations, tooling and equipment for remote in-service inspection of radioactive piping and pressure vessel systems

    International Nuclear Information System (INIS)

    Schmoker, D.S.; Swannack, D.L.

    1983-01-01

    In-Service Inspection programs are performed to monitor and verify the integrity of a nuclear power plant's primary pressure boundaries. Early detection of abnormal structural or material degradation could preclude serious damage to plant systems. This paper summarizes results obtained in use of remotely-operated nondestructive testing (NDT) equipment for inspection of reactor system components. Experience obtained in operating the Fast Flux Test Facility (FFTF) has provided a basis for field verification of remote NDT equipment designs and has suggested development improvements. Remote Viewing and data gathering systems used include periscopes, borescopes, fiberscopes, hybrid borescopes/fiberscopes, and closed circuit television. A summary of design consideration for inspection equipment and power plant design is presented to achieve improved equipment operation and reduction of plant maintenance downtime

  7. Beliefs concerning the reliability of nuclear power plant in-service inspections; Uskomuksia ydinvoimalaitoksissa suoritettavien tarkastusten luotettavuudesta

    Energy Technology Data Exchange (ETDEWEB)

    Kettunen, J. [VTT Automation, Espoo (Finland)

    1997-01-01

    The aim of the study was to investigate belief systems held by the officials responsible for the planning and supervision of NDT operations within the Finnish nuclear industry. They were asked to express their opinions on (1) the reliability of NDT methods in general, (2) the factors influencing the reliability of in-service inspections, and (3) the degree of reliability of the current inspections operations conducted by means of NDT methods in the Finnish nuclear power plants. Another goal of the study was to assess the adequacy of officials` beliefs (or belief systems). The research data was collected by interviewing representatives from Finnish power companies (Imatran Voima Oy and Teollisuuden Voima Oy), independent inspection organisations, and the Finnish Centre for Radiation and Nuclear Safety (STUK). The adequacy of the beliefs expressed was assessed by means of the results obtained from international NDT reliability studies and on the basis of interviewees` own justification. (refs.).

  8. An international survey of in-service inspection experience with prestressed concrete pressure vessels and containments for nuclear reactors

    International Nuclear Information System (INIS)

    1982-04-01

    An international survey is presented of experience obtained from the in-service surveillance of prestressed concrete pressure vessels and containments for nuclear reactors. Some information on other prestressed concrete structures is also given. Experience has been gained during the working life of such structures in Western Europe and the USA over the years since 1967. For each country a summary is given of the nuclear programme, national standards and Codes of Practice, and the detailed in-service inspection programme. Reports are then given of the actual experience obtained from the inspection programme and the methods of measurement, examination and reporting employed in each country. A comprehensive bibliography of over 100 references is included. The appendices contain information on nuclear power stations which are operating, under construction or planned worldwide and which employ either prestressed concrete pressure vessels or containments. (U.K.)

  9. Use of remote visual in-service inspection on nuclear power plants of the CEGB

    International Nuclear Information System (INIS)

    James, D.W.

    1985-01-01

    The main responsibility of the Remote Inspection Group is the design, development and procurement of the remote visual inspection equipment provided by the Generation Development and Construction Division as part of the extent of the supply for all the Central Electricity Generating Board's (CEGB) advanced gas-cooled reactors (AGR). The paper describes the operation of this equipment, together with the low light-level TV cameras that have been developed for carrying out routine remote visual inspections. The camera, known as the television remote inspection unit multi-purpose head (TRIUMPH), has been designed as a series of modules. With this system it is possible to take advantage of improvements in a particular part of the camera system and to arrange to backfit an improved module to existing TRIUMPHs. To minimize the time for carrying out routine inspections during shutdown, the AGRs have been provided with storage training and test facilities. These facilities are provided with full size mock-ups of the reactor internals so that the inspection equipment can be tested and the operating staff trained before the equipment is used on the reactor. One of the other responsibilities of the Remote Inspection Group is to carry out specific power plant remote visual inspections which are required to minimize costly plant shutdowns and construction delays. Examples are given of successful inspections that have been carried out. Over 12 years' experience has now been obtained in carrying out, at short notice, difficult inspections which involve tortuous access routes. The CEGB now holds a wide range of fibrescope and small TV cameras, together with the equipment for placing the viewing device in the correct location. A number of special fibrescopes have been developed for specific inspection needs and details of these, together with other fibrescopes owned by the CEGB, are provided. (author)

  10. Progress toward risk informed regulation

    International Nuclear Information System (INIS)

    Rogers, K.C.

    1997-01-01

    For the last several years, the NRC, with encouragement from the industry, has been moving in the direction of risk informed regulation. This is consistent with the regulatory principle of efficiency, formally adopted by the Nuclear Regulatory Commission in 1991, which requires that regulatory activities be consistent with the degree of risk reduction they achieve. Probabilistic risk analysis has become the tool of choice for selecting the best of several alternatives. Closely related to risk informed regulation is the development of performance based rules. Such rules focus on the end result to be achieved. They do not specify the process, but instead establish the goals to be reached and how the achievement of those goals is to be judged. The inspection and enforcement activity is based on whether or not the goals have been met. The author goes on to offer comments on the history of the development of this process and its probable development in the future. He also addresses some issues which must be resolved or at least acknowledged. The success of risk informed regulation ultimately depends on having sufficiently reliable data to allow quantification of regulatory alternatives in terms of relative risk. Perhaps the area of human reliability and organizational performance has the greatest potential for improvement in reactor safety. The ability to model human performance is significantly less developed that the ability to model mechanical or electrical systems. The move toward risk informed, performance based regulation provides an unusual, perhaps unique, opportunity to establish a more rational, more effective basis for regulation

  11. Discussion of in-service inspection planning for nuclear power plants

    International Nuclear Information System (INIS)

    Aoki, Takayuki; Takagi, Toshiyuki

    2012-01-01

    For creating an inspection plan for industrial plants like nuclear power plants, it is necessary to have a well-grounded basis. Therefore, this paper proposes a method for determining the following three elements of such a plan: the equipment to be inspected, the inspection method to be adopted, and the timing of its implementation using a scientific approach. The key idea is to analyze the components of the plan by employing the understanding of cancer detection and diagnosis in medical science and also to take an approach of creating a plan based on the characteristic features of the component and its aging degradation mode, the performance of the inspection method, and the relationship between the two. Taking all the above into account, the factors to be considered and the best way for inspecting the plants are presented in this paper. (author)

  12. X-ray tomographic in-service inspection of girth welds - The European project TomoWELD

    Energy Technology Data Exchange (ETDEWEB)

    Ewert, Uwe, E-mail: uwe.ewert@bam.de; Redmer, Bernhard, E-mail: uwe.ewert@bam.de; Walter, David, E-mail: uwe.ewert@bam.de; Thiessenhusen, Kai-Uwe, E-mail: uwe.ewert@bam.de; Bellon, Carsten, E-mail: uwe.ewert@bam.de [BAM Bundesanstalt für Materialforschung, Berlin (Germany); Nicholson, P. Ian, E-mail: ian.nicholson@twi.co.uk [TWI Technology Centre Wales, Port Talbot (United Kingdom); Clarke, Alan L. [TWI Technology Centre Wales, Port Talbot (United Kingdom); Finke-Härkönen, Klaus-Peter, E-mail: klaus.harkonen@ajat.fi [Oy AJAT Ltd., Helsinki (Finland)

    2015-03-31

    The new standard 'ISO 17636-2:2013: Non-destructive testing of welds - Radiographic testing - Part 2: X- and gamma-ray techniques with digital detectors', defines the practice for radiographic inspection of welded pipes for manufacturing and in-service inspection. It is applied in Europe for inspections of pipe welds in nuclear power plants as well as in chemical plants and allows a faster inspection with digital detector arrays (DDA) than with film. Nevertheless, it does not allow the evaluation of the depth and shape of volumetric and planar indications. In 2001 a planar tomography scanner, TomoCAR, was introduced for mechanized radiographic testing (RT) inspection and non-destructive measurement of cross sections. The project TomoWELD is based on a new concept of the scan geometry, an enhanced GPU based reconstruction, and the application of a new generation of photon counting DDAs based on CdTe crystal CMOS hybrids. The new detector permits the selection of energy thresholds to obtain an optimum energy range and reduction of the influence of scattered radiation. The concept and first measurements are presented. Flaw depth and shape of volumetric and planar irregularities can be determined.

  13. X-ray tomographic in-service inspection of girth welds - The European project TomoWELD

    International Nuclear Information System (INIS)

    Ewert, Uwe; Redmer, Bernhard; Walter, David; Thiessenhusen, Kai-Uwe; Bellon, Carsten; Nicholson, P. Ian; Clarke, Alan L.; Finke-Härkönen, Klaus-Peter

    2015-01-01

    The new standard 'ISO 17636-2:2013: Non-destructive testing of welds - Radiographic testing - Part 2: X- and gamma-ray techniques with digital detectors', defines the practice for radiographic inspection of welded pipes for manufacturing and in-service inspection. It is applied in Europe for inspections of pipe welds in nuclear power plants as well as in chemical plants and allows a faster inspection with digital detector arrays (DDA) than with film. Nevertheless, it does not allow the evaluation of the depth and shape of volumetric and planar indications. In 2001 a planar tomography scanner, TomoCAR, was introduced for mechanized radiographic testing (RT) inspection and non-destructive measurement of cross sections. The project TomoWELD is based on a new concept of the scan geometry, an enhanced GPU based reconstruction, and the application of a new generation of photon counting DDAs based on CdTe crystal CMOS hybrids. The new detector permits the selection of energy thresholds to obtain an optimum energy range and reduction of the influence of scattered radiation. The concept and first measurements are presented. Flaw depth and shape of volumetric and planar irregularities can be determined

  14. Structural features and in-service inspection of the LTHR-200 pressure vessel

    International Nuclear Information System (INIS)

    Xiong Dunshi; He Shuyan; Liu Junjie; Yu Suyuan

    1993-01-01

    LTHR-200 is a low temperature district-heating reactor. It adopts double-shell design pressure vessel and metal containment. Because of the safety and structural features of the reactor, the in-service inspection of the pressure vessel can be simplified greatly. LTHR-200 is an integrated arrangement. Both its core components and the main heat exchangers are contained in the reactor pressure vessel. The coolant of the main loop is run by a full-power natural circulation and there need no main pumps and pipes. Thus, the reactor pressure vessel constitutes the pressure boundary of the reactor's main loop coolant. In regard to these features, a small-sized containment is designed for the reactor. The metal safety container with a small volume is placed closely around the reactor pressure vessel. Outside the metal containment, there is a large reinforced concrete construction for the reactor. Their main operation and design parameters are as follows: The pressure vessel: operation pressure = 2.4 MPa; design pressure = 3.0 MPa; design temperature = 250 deg C; 40 year fast neutron (E>1MeV) fluence in the belt-line region = < 10E16n/cm; internal diameter = 5000 mm; material SA516-70; shell thickness 65 mm; The metal containment: maximum operation pressure = 1.8 MPa; design pressure = 1.8 MPa; design temperature = 250 deg. C; upper internal diameter 7000 mm; lower internal diameter = 5600 mm; material = SA516-70; shell thickness, upper part = 80 mm; lower part = 50 mm. All penetrating pipes through the pressure vessel are located at the top penetration section of the shell. All the internal diameters of penetrating pipes are less than 50 mm. Inside and outside the metal containment wall respectively, isolating valves are connected to the reactor coolant pipe which passes through the containment. These two isolating valves use different driving methods. Every penetrating part of the reactor construction uses a proper form of structure according to safety requirements

  15. Development of automated ultrasonic device for in-service inspection of ABWR pressure vessel bottom head

    International Nuclear Information System (INIS)

    Kojima, Y.; Matsuyama, A.

    1995-01-01

    An automated device and its controller have been developed for the bottom head weld examination of pressure vessel of Advanced Boiling Water Reactor (ABWR). The internal pump casings and the housings of control rod prevent a conventional ultrasonic device from scanning the required inspection zone. With this reason, it is required to develop a new device to examine the bottom head area of ABWR. The developed device is characterized by the following features. (1) Composed of a mother vehicle and a compact inspection vehicle. They are connected only by an electric wire without using the conventional arm mechanism. (2) The mother vehicle travels on a track and lift up the inspection vehicle to the vessel. (3) The mother vehicle can automatically attach the inspection vehicle to the bottom head, and detach the inspection vehicle from it. (4) Collision avoidance control function with a touch sensor is installed at the front of the inspection vehicle. The device was successfully demonstrated using a mock-up of reactor pressure vessel

  16. Proposals for in-service inspection and monitoring of selected components located within or part of the primary containment of sodium cooled fast reactors

    International Nuclear Information System (INIS)

    Bolt, P.R.

    1976-01-01

    Design and operational experience of CEGB gas cooled reactors and certain overseas reactor plant is reviewed in relation to in-service inspection and monitoring capabilities. Design guidelines and preliminary proposals are given for in-service inspection and monitoring of selected components located within or part of the primary containment of sodium cooled fast reactors. Specific comments are made on the items of further design and development work believed to be necessary

  17. Ageing Management Programme: An Experience of In-Service Inspection of the Kartini Heat Exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Nitiswati, S., E-mail: nitis@batan.go.id [Centre for Reactor Technology and Nuclear Safety, National Nuclear Energy Agency (BATAN), Jakarta (Indonesia); Syarip,; Tjiptono, T.; Wantana, [Centre for Accelerator and Material Process Technology, National Nuclear Energy Agency (BATAN), Yogyakarta (Indonesia)

    2014-08-15

    This paper discusses an experience on ISI of the Kartini reactor heat exchanger, as part of the implementation of an ageing management programme. Kartini reactor is located in Yogyakarta, Indonesia. The heat exchanger was constructed for 250 kW capacity. The type of heat exchanger is shell with tube recirculation. Tube material is stainless steel 304, and the shell and baffle plate materials are carbon steel. The heat exchanger has 72 tubes, its outer and inner diameters respectively are 19 and 16 mm, and tube thickness is 1.5 mm. The aim of ISI was to obtain and evaluate the heat exchanger’s condition including the detection of any possible local tube thinning, pitting corrosion or gradual thinning, and determine whether any degradation or deterioration of the heat exchanger could have a significant impact to safety. The heat exchanger was inspected utilizing eddy current equipment in 2003 and 2006. Inspection results in 2003 determined that 12 heat exchanger tubes have a thinning degradation level ranging from 10% up to 60% of the outer diameter due to pitting corrosion. Deterioration of baffle plates has been linked to general corrosion attack. Inspection results in 2006 showed a consistent thinning degradation level with the previous inspection in 2003. So far heat exchanger performance is still satisfactory, as defined by the transfer of primary heat for a 2°C difference between inlet and outlet as required. (author)

  18. Inter-vessels in-service inspection of Super-Phenix

    International Nuclear Information System (INIS)

    Asty, M.; Saglio, R.; Viard, J.; Lerat, B.

    1984-01-01

    The vessels design of fast breeder reactor Super-Phenix enables inspection during operating time. A self-moving machine -MIR- has been built up especially for that purpose. It is able to carry out visual and ultrasonorous inspection. MIR structure is that of a tetrahedron, all tops of which are fitted with two wheels, as for traction and direction. The wheels are leaning on booth the two vessels. Thanks to a computer-assisted control system, MIR is able to move along in every part of the inter-vessels space. Studies have been carried on at the French Commissariat a l'Energie Atomique, by two Sections of the advanced technologies Service. After outlining MIR working conditions, its main characteristics are described [fr

  19. The 1978 first in-service inspection of the reactor pressure vessel of the second unit of the Greifswald nuclear power plant

    International Nuclear Information System (INIS)

    Pastor, D.; Busch, R.; Hildebrandt, E.; Redlich, K.H.

    1979-01-01

    The reactor pressure vessel and the primary coolant circuit of the second 440-MW(e) unit of the Greifswald nuclear power plant were subjected to an in-service inspection. Extent of the inspection, development and construction of a reactor inspection container as well as the nondestructive materials testing methods used are described. Further, problems of performing the inspection, such as needs of time and personnel and radiation exposure, are considered. Finally, it is stated that the reactor pressure vessel was in safe operating state. (author)

  20. In-service inspection of the vessels of nuclear submarine reactors

    International Nuclear Information System (INIS)

    Saglio, R.; Mercier L'Abbe, G.

    1977-02-01

    Description is given of a machine of automatic inspection of the reactor vessels of nuclear submarines, that was developed by the French Atomic Energy Commission (CEA). A focused ultrasound testing method is used. The equipment such described meets the safety requirements prescribed for the primary circuits of nuclear submarine boiler plants. The sensitivity and resolution power of the apparatus allow such high precision to be obtained as rupture mechanics gains a credibility that could not have been obtained with using conventional apparatus [fr

  1. Application of phased arrays in basic and in-service inspection

    International Nuclear Information System (INIS)

    Gebhardt, W.; Schwarz, H.P.; Bonitz, F.; Woll, H.

    1985-01-01

    In the scope of the reactor safety research program of the Federal Ministry of Research and Technology a flexible microcomputer controlled phased array system was developed. Meanwhile, several industrial prototypes for simple and complicated applications are built up. The applicability of phased array systems in NDE for basic and inservice inspections of reactor pressure vessels is investigated. Methods for defect detection, reconstruction and classification are described

  2. Automation of eddy current system for in-service inspection of turbine and generator bores

    International Nuclear Information System (INIS)

    Viertl, J.R.M.

    1988-01-01

    The most commonly applied inspection method for ferromagnetic turbine and generator rotor bores is the magnetic particle test technique. This method is subjective, depends on the test operator's skill and diligence in identifying test indications, and suffers from poor repeatability, especially for small indications. Automation would improve repeatability. However, magnetic particle tests are not easily automated, because the data are in the form of sketches, photographs, and written and oral descriptions of the indications. Eddy current inspection has obvious potential to replace magnetic particle methods in this application. Eddy current tests can be readily automated, as the data are in the form of voltages that can be recorded, digitized, and manipulated by a computer. The current project continues the investigation of the correlation between eddy current and magnetic particle inspection. Two systems have been combined to acquire eddy current data automatically. This combination of systems consists of the Nortec-25L Eddyscope (to provide the analog eddy current signals) and the General Electric DATAQ (TM) System (to perform the automatic data acquisition). The automation of the system is discussed

  3. Evaluation and improvement in nondestructive examination (NDE) reliability for in-service inspection of light water reactors

    International Nuclear Information System (INIS)

    Deffenbaugh, J.D.; Good, M.S.; Green, E.R.; Heasler, P.G.; Simonen, F.A.; Spanner, J.C.; Taylor, T.T.

    1988-01-01

    The evaluation and improvement of NDE Reliability for In-service Inspection (ISI) of Light Water Reactors (NDE Reliability) Program at Pacific Northwest Laboratory (PNL) was established to determine the reliability of current ISI techniques and to develop recommendations that will ensure a suitably high inspection reliability. The objectives of this NRC program are to: determine the reliability of ultrasonic ISI performed on commercial light-water reactor (LWR) primary systems; determine the impact of NDE unreliability on system safety and determine the level of inspection reliability required to ensure a suitably low failure probability using probabilistic fracture mechanics analysis; evaluate the degree of reliability improvement that could be achieved using improved and advanced NDE technique; and recommend revisions to ASME Code, Section XI, and Regulatory Requirements, based on material properties, service conditions, and NDE uncertainties, that will ensure suitably low failure probabilities. The program consists of three basic tasks: a Piping task, a Pressure Vessel task, and an Evaluation and Improvement in NDE Reliability task. The major efforts were concentrated in the Piping task and the Evaluation and Improvement in NDE Reliability task

  4. Some reliability targets affecting the necessary provisions for in-service inspection and monitoring of LMFBR engineering components

    International Nuclear Information System (INIS)

    Bolt, P.R.

    1980-01-01

    The possible consequences of failure of primary and secondary sodium circuit components are discussed with particular reference to post incident fault diagnosis, remedial procedures and outage durations. The core support structures and steam generator units are identified as particularly important components in terms of economic consequence of their failure. Important safety considerations may also apply. Levels of reliability for core support and steam generator integrity, necessary to meet economic and certain safety criteria, are discussed and quantitative data is given. Possible failure and deterioration mechanisms which could result in unacceptable reductions in reliability are then identified for the core support and steam generator units. Following a consideration of the reliability targets and possible causes of loss of reliability, an appraisal is made of the necessary extent of in-service data to be obtained on component behaviour and condition. In-service inspection and monitoring methods that could be used to obtain this data are described. Consideration is given to UK and overseas inspection experience on LMFBR and other nuclear plant. (author)

  5. Some reliability targets affecting the necessary provisions for in-service inspection and monitoring of LMFBR engineering components

    Energy Technology Data Exchange (ETDEWEB)

    Bolt, P R [Fast Reactor Engineering, Plant Engineering Department, CEGB, Barnwood, Gloucester (United Kingdom)

    1980-11-01

    The possible consequences of failure of primary and secondary sodium circuit components are discussed with particular reference to post incident fault diagnosis, remedial procedures and outage durations. The core support structures and steam generator units are identified as particularly important components in terms of economic consequence of their failure. Important safety considerations may also apply. Levels of reliability for core support and steam generator integrity, necessary to meet economic and certain safety criteria, are discussed and quantitative data is given. Possible failure and deterioration mechanisms which could result in unacceptable reductions in reliability are then identified for the core support and steam generator units. Following a consideration of the reliability targets and possible causes of loss of reliability, an appraisal is made of the necessary extent of in-service data to be obtained on component behaviour and condition. In-service inspection and monitoring methods that could be used to obtain this data are described. Consideration is given to UK and overseas inspection experience on LMFBR and other nuclear plant. (author)

  6. Risk informed life cycle plant design

    International Nuclear Information System (INIS)

    Hill, Ralph S. III; Nutt, Mark M.

    2003-01-01

    Many facility life cycle activities including design, construction, fabrication, inspection and maintenance are evolving from a deterministic to a risk-informed basis. The risk informed approach uses probabilistic methods to evaluate the contribution of individual system components to total system performance. Total system performance considers both safety and cost considerations including system failure, reliability, and availability. By necessity, a risk-informed approach considers both the component's life cycle and the life cycle of the system. In the nuclear industry, risk-informed approaches, namely probabilistic risk assessment (PRA) or probabilistic safety assessment (PSA), have become a standard tool used to evaluate the safety of nuclear power plants. Recent studies pertaining to advanced reactor development have indicated that these new power plants must provide enhanced safety over existing nuclear facilities and be cost-competitive with other energy sources. Risk-informed approaches, beyond traditional PRA, offer the opportunity to optimize design while considering the total life cycle of the plant in order to realize these goals. The use of risk-informed design approaches in the nuclear industry is only beginning, with recent promulgation of risk-informed regulations and proposals for risk-informed codes. This paper briefly summarizes the current state of affairs regarding the use of risk-informed approaches in design. Key points to fully realize the benefit of applying a risk-informed approach to nuclear power plant design are then presented. These points are equally applicable to non-nuclear facilities where optimization for cost competitiveness and/or safety is desired. (author)

  7. Evaluation of sampling plans for in-service inspection of steam generator tubes

    International Nuclear Information System (INIS)

    Kurtz, R.J.; Heasler, P.G.; Baird, D.B.

    1994-02-01

    This report summarizes the results of three previous studies to evaluate and compare the effectiveness of sampling plans for steam generator tube inspections. An analytical evaluation and Monte Carlo simulation techniques were the methods used to evaluate sampling plan performance. To test the performance of candidate sampling plans under a variety of conditions, ranges of inspection system reliability were considered along with different distributions of tube degradation. Results from the eddy current reliability studies performed with the retired-from-service Surry 2A steam generator were utilized to guide the selection of appropriate probability of detection and flaw sizing models for use in the analysis. Different distributions of tube degradation were selected to span the range of conditions that might exist in operating steam generators. The principal means of evaluating sampling performance was to determine the effectiveness of the sampling plan for detecting and plugging defective tubes. A summary of key results from the eddy current reliability studies is presented. The analytical and Monte Carlo simulation analyses are discussed along with a synopsis of key results and conclusions

  8. Tridimensional ultrasonic images analysis for the in service inspection of fast breeder reactors

    International Nuclear Information System (INIS)

    Dancre, M.

    1999-11-01

    Tridimensional image analysis provides a set of methods for the intelligent extraction of information in order to visualize, recognize or inspect objects in volumetric images. In this field of research, we are interested in algorithmic and methodological aspects to extract surface visual information embedded in volume ultrasonic images. The aim is to help a non-acoustician operator, possibly the system itself, to inspect surfaces of vessel and internals in Fast Breeder Reactors (FBR). Those surfaces are immersed in liquid metal, what justifies the ultrasonic technology choice. We expose firstly a state of the art on the visualization of volume ultrasonic images, the methods of noise analysis, the geometrical modelling for surface analysis and finally curves and surfaces matching. These four points are then inserted in a global analysis strategy that relies on an acoustical analysis (echoes recognition), an object analysis (object recognition and reconstruction) and a surface analysis (surface defects detection). Few literature can be found on ultrasonic echoes recognition through image analysis. We suggest an original method that can be generalized to all images with structured and non-structured noise. From a technical point of view, this methodology applied to echoes recognition turns out to be a cooperative approach between morphological mathematics and snakes (active contours). An entropy maximization technique is required for volumetric data binarization. (author)

  9. Current products and future plan of regulatory research for risk-informed regulation in Korea

    International Nuclear Information System (INIS)

    Sung, Key Yong; Lee, Chang Ju; Kim, Woong Sik; Kim, Hho Jung

    2003-01-01

    The first phase of a regulatory research project for risk-informed regulation (RIR) and applications (RIA) was finished in March of 2002. Various results that could be useful for preparing Korean RIR system have been developed. One of the remarkable outputs is development of reactor safety goals and acceptance criteria for RIR and RIA in Korea. The Safety Goal has a 4-tier hierarchical structure and each tier has specified goals classified for their usage. Regulatory review guides for probabilistic safety assessment (PSA) including level-1, level-2 and low power and shutdown PSA have been updated by reflecting new information obtained from not only the overseas documents but also experience and insights from regulatory review in Korea. In addition, draft regulatory guides for risk-informed in-service inspection, in-service testing, importance ranking of motor-operated valves, and AOT/STI change of Technical Specifications have been developed for preparing ongoing and future licensing work. Risk-based inspection guides with inspection items selected from a viewpoint of risk importance have been suggested for Korean standard NPPs as well. In the second phase of a research project (April of 2002 to March of 2005), two regulatory research projects on RIR were initiated. One is a study on institutionalization of risk-informed and performance-based regulation. Main topics of this project are evaluation of benefit and characteristics of RIR, development of optimized Korean RIR model, impact analysis for the change of current regulation framework, and suggestion of RIR-related laws and rules. The other is focusing on the development in the areas of a regulatory audit PSA model and regulatory guides for risk monitoring, and application techniques of risk information to the significance determination of plant performance indicators and inspection findings. It is expected that a concrete scheme and detailed regulatory techniques for embodiment of RIR system in Korea will be

  10. PAT portable appliance testing : in-service inspection and testing of electrical equipment

    CERN Document Server

    Scaddan, Brian

    2015-01-01

    The Electricity at Work Regulations 1989 requires any electrical system to be constructed, maintained and used in such a manner as to prevent danger. This means that inspection and testing of systems, including portable appliances, is needed in order to determine if maintenance is required. This book explains in clear language what needs to be done and includes expert advice on legislation as well as actual testing. The book contains an appendix providing the electrical fundamentals needed by non-specialists and also has sample questions (with answers) for the C&G 2377 exam. It is also an ideal revision guide for the non-specialist, such as maintenance staff and caretakers who carry out these tasks part-time, alongside their many other duties.

  11. Application of non-destructive testing and in-service inspections to research reactors and preparation of ISI programme and manual for WWR-C research reactors

    International Nuclear Information System (INIS)

    Khattab, M.

    1996-01-01

    The present report gives a review on the results of application of non-destructive testing and in-service inspections to WWR-C reactors in different countries. The major problems related to reactor safety and the procedure of inspection techniques are investigated to collect the experience gained from this type of reactors. Exchangeable experience in solving common problems in similar reactors play an important role in the effectiveness of their rehabilitation programmes. 9 figs., 4 tabs

  12. Evaluation of sampling schemes for in-service inspection of steam generator tubing

    International Nuclear Information System (INIS)

    Hanlen, R.C.

    1990-03-01

    This report is a follow-on of work initially sponsored by the US Nuclear Regulatory Commission (Bowen et al. 1989). The work presented here is funded by EPRI and is jointly sponsored by the Electric Power Research Institute (EPRI) and the US Nuclear Regulatory Commission (NRC). The goal of this research was to evaluate fourteen sampling schemes or plans. The main criterion used for evaluating plan performance was the effectiveness for sampling, detecting and plugging defective tubes. The performance criterion was evaluated across several choices of distributions of degraded/defective tubes, probability of detection (POD) curves and eddy-current sizing models. Conclusions from this study are dependent upon the tube defect distributions, sample size, and expansion rules considered. As degraded/defective tubes form ''clusters'' (i.e., maps 6A, 8A and 13A), the smaller sample sizes provide a capability of detecting and sizing defective tubes that approaches 100% inspection. When there is little or no clustering (i.e., maps 1A, 20 and 21), sample efficiency is approximately equal to the initial sample size taken. Thee is an indication (though not statistically significant) that the systematic sampling plans are better than the random sampling plans for equivalent initial sample size. There was no indication of an effect due to modifying the threshold value for the second stage expansion. The lack of an indication is likely due to the specific tube flaw sizes considered for the six tube maps. 1 ref., 11 figs., 19 tabs

  13. Case history of a 94 MVA turbo-generator retired after 190.000 hours of service by defects revealed by boresonic in-service inspection

    International Nuclear Information System (INIS)

    Porro, F.; Santoro, M.

    1990-01-01

    The case-history of a turbogenerator manufactured by Ansaldo on 1957 and turned on operation on 1958 then retired after 30 years of operation, with a total of 190.000 hours of service, by defects revealed trough boresonic inspections, will be presented. The rotor was inspected a first time after 130.000 hours of service and was overbored in order to allow further service operations. After other 60.000 hours of service operation the rotor underwent to a new in-service inspection that showed an unacceptable condition. The rotor, retired from service, has been destined to destructive tests in order to verify non-destructive predictions

  14. In-service inspection of condenser tubes by means of electrochemical methods

    International Nuclear Information System (INIS)

    Taelemans, G.

    The commissioning of an increasing number of large nuclear power plants involves an increased significance of such condenser tube problems as: - erosion on tube ends, - generalized corrosion and pitting corrosion, - deposits in the tubes. In order to solve such problems, investigations were performed especially focused on a measurement technique that enables in-service behaviour of condenser tubes to be monitored. For such a purpose, measurement of the polarization resistance has been adopted. The existing corrosion products and scaled-off iron oxides were eliminated by means of a carborundum balls processing, as clearly appears from polarization resistance reduction. Then iron sulphate was injected in order to build a new and better protective layer. In addition, the tube was kept clean by means of foam rubber balls. There is a second implementation area: fouled condenser tubes. A significant polarization resistance reduction is noted during the acid cleaning. (orig.) [de

  15. Guided wave technology for in-service inspection and online monitoring for long term operation of nuclear power plants

    International Nuclear Information System (INIS)

    Bertoncini, Francesco; Raugi, Marco; Cappelli, Mauro; Cordella, Francesco; Mazzini, Davide

    2015-01-01

    In-Service Inspection (ISI) and monitoring of all equipment (Systems, Structures and Components, SSCs) of a Nuclear Power Plant (NPP), are actions aimed at preventing failures both for economical and safety purposes. SSCs ageing due to stresses such as corrosion, load variations, flow conditions, temperature and neutron irradiation can be a potential limit for NPP life extension or operation beyond their license term (Long Term Operation. LTO). ISI has a main role on the actual possibility of LTO assuring the required safety. Guided Waves are structure-borne ultrasonic waves that propagate along the structure confined and guided by its geometric boundaries. Guided Wave Testing can find defect locations through long-range screening using low-frequency waves (from 5 to 250 kHz). The technology is regularly used for pipe testing in the oil and gas industry. In the nuclear industry, regulators are working to standardize monitoring and inspection procedures. To use the technology inside an active plant, operators must solve issues like high temperatures (up to more than 300degC inside a light-water reactor's primary piping), high wall thickness of components in the primary circuit and characteristic defect typologies. Magnetostrictive sensors are expected to overcome such issues due to their physical properties, namely robust constitution and simplicity. Recent experimental results have demonstrated magnetostrictive transducers can withstand temperatures close to 300degC. In this paper, new experimental tests conducted using such a methodology will be described and open issues related to high temperature guided wave applications (e.g. wave velocity or amplitude fluctuations during propagation in variable temperature components) will be discussed. (author)

  16. An experience with in-service fabrication and inspection of austenitic stainless steel piping in high temperature sodium system

    Energy Technology Data Exchange (ETDEWEB)

    Ravi, S., E-mail: sravi@igcar.gov.in; Laha, K.; Sakthy, S.; Mathew, M.D.; Bhaduri, A.K.

    2015-04-01

    Highlights: • Procedure for changing 304L SS pipe to 316L SS in sodium loop has been established. • Hot leg made of 304L SS was isolated from existing cold leg made of 316LN SS. • Innovative welding was used in joining the new 316L SS pipe with existing 316LN SS. • The old components of 304L SS piping have been integrated with the new piping. - Abstract: A creep testing facility along with dynamic sodium loop was installed at Indira Gandhi Centre for Atomic Research, Kalpakkam, India to assess the creep behavior of fast reactor structural materials in flowing sodium. Type 304L austenitic stainless steel was used in the low cross section piping of hot-leg whereas 316LN austenitic stainless steel in the high cross section cold-leg of the sodium loop. The intended service life of the sodium loop was 10 years. The loop has performed successfully in the stipulated time period. To enhance its life time, it has been decided to replace the 304L piping with 316L piping in the hot-leg. There were more than 300 welding joints involved in the integration of cold-leg with the new 316L hot-leg. Continuous argon gas flow was maintained in the loop during welding to avoid contamination of sodium residue with air. Several innovative welding procedures have been adopted for joining the new hot-leg with the existing cold-leg in the presence of sodium residue adopting TIG welding technique. The joints were inspected for 100% X-ray radiography and qualified by performing tensile tests. The components used in the discarded hot-leg were retrieved, cleaned and integrated in the renovated loop. A method of cleaning component of sodium residue has been established. This paper highlights the in-service fabrication and inspection of the renovation.

  17. Application of risk based inspection as a part of life management of nuclear power plants

    International Nuclear Information System (INIS)

    Vinod, Gopika; Babar, A.K.; Saraf, R.K.; Kushwaha, H.S.; Venkat Raj, V.

    2002-01-01

    Full text: Risk Informed approach is a systematic effort to improve plant safety in a more efficient manner by distributing the available safety resources depending on the importance to plant safety. This approach has found immense application in various aspects associated with Nuclear Power Plants, including design, manufacturing, operation and regulation. Typical applications of Risk Informed approach are in Technical Specification, In-Service Inspection (ISI) requirements, Motor Operated Valve testing, Configuration Control etc. In order to cater to such variety of Probabilistic Safety Assessment (PSA) based Risk Informed requirements, a software package, 'Risk Monitor' has been developed by the authors. An important application of Risk informed approach that has been undertaken for Indian Pressurised Heavy Water Reactor (IPHWR) is towards Risk Informed In-Service Inspection (RI-ISI). Studies are being conducted to evolve an inspection plan that is optimised to provide effective inspections at the right location with a proper inspection frequency. Using risk informed approach, the identification of system / component for inspection resource allocation is based on the results from Level 1 PSA of a NPP. Even though this methodology can be employed on any of the nuclear components/systems such as mechanical systems, instrumentation, etc., as a starting point, piping has been considered for employing Risk Informed Inspection. Plant risk assessment is modelled through the analysis of Core Damage Frequency (CDF) using PSA models. Risk Informed Inspection program of piping involves the estimation of failure probability or frequency of a piping segment and estimation of consequences of piping failures. ISI program changes could affect the failure probability values of piping and can introduce a change in CDF. These effects can be brought out through the implementation of Risk Informed inspection strategy. Various importance measures like Fussel-Vesely, Birnbaum

  18. In-service inspection of nuclear reactor vessels and steam generators. Results and evolution of the technics

    International Nuclear Information System (INIS)

    Rapin, Michel; Saglio, Robert.

    1978-01-01

    Methods and original technics have been developed by the CEA for inspection of the primary coolant circuit of PWR. Multifrequency Eddy currents for inspection of steam generators tubes gudgeons and bolts; focussed ultrasonics to test all the welds of the reactor vessel and its cover of mixed welds of tanks and steam generators, pressurizer welds and gudgeons from the inside; gamma radiography of vessel mixed welds, televisual examination of the stainless steel lining of the reactor vessel and its cover. Use of these technics is made with specific automatic machines designed either for inspection of steam generator tubes or for complete inspection of the vessel. Several reactors were inspected with these devices [fr

  19. An expert panel approach to support risk-informed decision making

    International Nuclear Information System (INIS)

    Pulkkinen, U.; Simola, K.

    2000-01-01

    The report describes the expert panel methodology developed for supporting risk-informed decision making. The aim of an expert panel is to achieve a balanced utilisation of information and expertise from several disciplines in decision-making including probabilistic safety assessment as one decision criterion. We also summarise the application of the methodology in the STUK's RI-ISI (Risk-Informed In-Service Inspection) pilot study, where the expert panel approach was used to combine the deterministic information on degradation mechanisms and probabilistic information on pipe break consequences. The expert panel served both as a critical review of the preliminary results and as a decision support for the final definition of risk categories of piping. (orig.)

  20. Comparison between different methods for inspection of wooden poles in service in electricity distribution networks; Comparacao entre diferentes metodos de inspecao de postes de madeira em servico em redes de distribuicao de energia

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, M.A.O.; Pires, M.; Dedavid, B.A.; Vidor, F.L.R.; Oliveira, W.S.; Abruzzi, R.C. [Pontificia Univ. Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia e Tecnologia de Materiais (PGETEMA)], Email: mpires@pucrs.br

    2010-07-01

    The pole is the main support structure of the electric network and should be inspected regularly to ensure system security. The aim of this study is to compare traditional and instrumental inspection methods of the wooden poles in service in AES Sul power distribution network (Montenegro, RS). The inspections were conducted in about 180 poles in two measurement campaigns (2001 and 2010). The procedure was based on the traditional inspection (visual inspection, percussion and effort lateral) and instrumental method based on Polux equipment that measures the penetration resistance and moisture content of wood. The results were compared in search of assertiveness of the methods used to subsidize the standardization of inspection procedures. (author)

  1. Role of in-service inspection and maintenance in reliability assurance of concrete structures in nuclear plants

    International Nuclear Information System (INIS)

    Ellingwood, B.R.; Mori, Y.

    1993-01-01

    The degradation in strength of a component with random damage is evaluated using a growth model for individual damages which can be obtained from experimental data. The distribution function of damage intensity after inspection and repair is updated using a Bayesian analysis that takes the quality of inspection into account. With this posterior distribution, the time-dependent strength after the inspection and repair can be evaluated. Time-dependent reliability analysis can be used to determine inspection/repair strategies that are necessary to keep the failure probability of the component lower than an established target. (author)

  2. Capability evaluation of Eddy current and ultrasonic in-service inspections of steam generator tubes. A status report of PISC III Action 5

    International Nuclear Information System (INIS)

    Bieth, M.; Birac, C.; Comby, R.

    1998-01-01

    Document summarizes the PISC III (Programme for the Inspection of Steel Components) report No. 41, full description of the PISC III Action 5 on Steam Generator Tubes Inspection, containing all details and final conclusions which are still to be approved by the PISC III Management Board. The report was prepared by the reference laboratory of PISC under guidance and with continuous contribution of the members of the Data Analysis Group (DAG) of this PISC III. There were several procedures which demonstrated good detection capability of major flaws in typical locations of the steam generator. Conclusions of the exercise indicate that capability demonstration is necessary to qualify in service inspection procedures for steam generator tubes

  3. Experience with ANSI N14.30 for in-service inspections of semi-trailer used for spent fuel shipments

    International Nuclear Information System (INIS)

    Hirtz, G.J.

    1998-05-01

    On July 18, 1996, the Oak Ridge National Laboratory (ORNL) resumed shipping spent fuel in interstate commerce after a 10 year suspension of this activity. This shipment was conducted using a Nuclear Regulatory Commission licensed spent fuel transport package purchased from General Electric Company by ORNL for the purpose of moving High Flux Isotope Reactor spent fuel to the Savannah River Site. The trailer, fabricated to the ANSI N14.30, Semi-Trailers Employed in the Highway Transport of Weight Concentrated Radioactive Loads Design, Fabrication, and Maintenance, has recently undergone its first scheduled in-service inspection. This paper presents the experience gained from interpretation and application of the ANSI N14.30 standard focusing on the in-service inspection for the structure of the trailer. Initially, the term weight concentrated is illustrated giving detail to the location and center of gravity of the 33,500 pound shipping container and forces induced by the tie down system. Basic information about the design stresses and initial testing provided by the manufacturer are used as a lead-in to the requirements of the standard. The task of examining the trailer structure provided many lessons and required considerable effort. All of the support personnel were provided by ORNL; the garage mechanics and the certified inspection engineers had never been involved in applying ANSI N14.30. Other obstacles were the lack of existing inspection procedures for this particular activity and the lack of a previous experience interpreting the standard with regard to repair work. Some of these questions were resolved by clarification received from the writers of the standard, and others were resolved by the teamwork between the manufacturer and ORNL. This experience illustrated the importance of the trailer manufacturer as a participant in the decisions made concerning in-service inspection and maintenance

  4. An in-service inspection method: the use of focused probes for the detection and sizing in DDT Plates 1 and 2

    International Nuclear Information System (INIS)

    Birac, A.M.; Pincemaille, G.; Saglio, R.; Cattiauz, G.; Morisseau, P.

    1983-01-01

    As part of the DDT programme to evaluate the nondestructive testing methods used during the in-service inspection (ISI) of PWR vessels, the UKAEA asked the CEA-STA-SCND to perform the ultrasonic examination of two test-plates. Each plate was bisected across its full width by a full-thickness butt-weld in which calibrated defects of various natures, dimensions, orientations have been inserted. It was required that the implementation of control, the equipment and the subsequent data analysis represent as nearly as possible the French procedure in force during the pre-service and in-service inspection of a PWR vessel. As suggested by the UKAEA, to evaluate the influence of examiners on the results, the examinations have been carried out twice by two independent teams: one from the CEA-STA-SCND and the second from INTERCONTROLE (a CEA subsidiary company). Procedure and results are given. (author)

  5. Risk Informed Structural Systems Integrity Management

    DEFF Research Database (Denmark)

    Nielsen, Michael Havbro Faber

    2017-01-01

    The present paper is predominantly a conceptual contribution with an appraisal of major developments in risk informed structural integrity management for offshore installations together with a discussion of their merits and the challenges which still lie ahead. Starting point is taken in a selected...... overview of research and development contributions which have formed the basis for Risk Based Inspection Planning (RBI) as we know it today. Thereafter an outline of the methodical basis for risk informed structural systems integrity management, i.e. the Bayesian decision analysis is provided in summary....... The main focus is here directed on RBI for offshore facilities subject to fatigue damages. New ideas and methodical frameworks in the area of robustness and resilience modeling of structural systems are then introduced, and it is outlined how these may adequately be utilized to enhance Structural Integrity...

  6. Qualification of NDT systems for in-service inspections of nuclear power plant pressure vessels; Ydinvoimalaitosten paineastioiden maeaeraeaikaistarkastuksissa kaeytettaevien NDT-jaerjestelmien paetevoeinti

    Energy Technology Data Exchange (ETDEWEB)

    Elfving, K

    1998-11-01

    The goal of this study is to determine the requirements of the in-service inspection qualification in Europe, their feasibility in practice and to find out possible manufacture defects in test pieces used in practical trials. The literature study consists of qualification requirements set by European regulatory bodies and by the European nuclear power utilities. Also a brief summary of qualification requirements set by ASME Code, Section XI and comparison between ASME and European qualification requirements is included 24 refs.

  7. Automatic ultrasonic pre-service, and in-service inspection of pressurized components of the primary circuit of nuclear power stations

    International Nuclear Information System (INIS)

    Muller, G.P.; Hallermeier, L.; Heinrich, D.; Grabendorfer, W.; Rebrmann, M.

    1985-01-01

    Ultrasonic pre-service and especially in-service inspection activities on the primary circuit of nuclear power stations form an essential part of the maintenance work that must be performed throughout the lifetime to ensure plant integrity. Consequently, the equipment required to carry out these inspections must be continuously improved in respect of reliability, safety, accuracy and ease of handling in order to minimize disturbances and repairs and reduce radiation exposure of the personnel. The authors' discussion of technique, equipment and performance of automated ultrasonic inspection is based on 15 years of experience in the testing of components of the primary circuit in nuclear power stations. To cover all inspection areas of the RPV of a PWR, four different manipulators are required, two for the closure head, one for the studs and one for the cylindrical shell and bottom closure. The use of the newly developed equipment, which naturally meets all the recommendations of the licensing authorities, allows for the automatic inspection of the components of primary circuit of nuclear power stations and the thus helps to substantially decrease the radiation exposure of the personnel. All the manipulators and their control consoles were designed and manufactured by M.A.N., Nuremberg while the ultrasonic electronic system was developed by Krautkramer, Cologne

  8. A pilot application of risk-based methods to establish in-service inspection priorities for nuclear components at Surry Unit 1 Nuclear Power Station

    International Nuclear Information System (INIS)

    Vo, T.; Gore, B.; Simonen, F.; Doctor, S.

    1994-08-01

    As part of the Nondestructive Evaluation Reliability Program sponsored by the US Nuclear Regulatory Commission, the Pacific Northwest Laboratory is developing a method that uses risk-based approaches to establish in-service inspection plans for nuclear power plant components. This method uses probabilistic risk assessment (PRA) results and Failure Modes and Effects Analysis (FEMA) techniques to identify and prioritize the most risk-important systems and components for inspection. The Surry Nuclear Power Station Unit 1 was selected for pilot applications of this method. The specific systems addressed in this report are the reactor pressure vessel, the reactor coolant, the low-pressure injection, and the auxiliary feedwater. The results provide a risk-based ranking of components within these systems and relate the target risk to target failure probability values for individual components. These results will be used to guide the development of improved inspection plans for nuclear power plants. To develop inspection plans, the acceptable level of risk from structural failure for important systems and components will be apportioned as a small fraction (i.e., 5%) of the total PRA-estimated risk for core damage. This process will determine target (acceptable) risk and target failure probability values for individual components. Inspection requirements will be set at levels to assure that acceptable failure probabilistics are maintained

  9. Risk-informed decision making a keystone in advanced safety assessment

    International Nuclear Information System (INIS)

    Reinhart, M.

    2007-01-01

    Probabilistic Safety Assessment (PSA) has provided extremely valuable complementary insight, perspective, comprehension, and balance to deterministic nuclear reactor safety assessment. This integrated approach of risk-informed management and decision making has been called Risk-Informed Decision Making (RIDM). RIDM provides enhanced safety, reliability, operational flexibility, reduced radiological exposure, and improved fiscal economy. Applications of RIDM continuously increase. Current applications are in the areas of design, construction, licensing, operations, and security. Operational phase safety applications include the following: technical specifications improvement, risk-monitors and configuration control, maintenance planning, outage planning and management, in-service inspection, inservice testing, graded quality assurance, reactor oversight and inspection, inspection finding significance determination, operational events assessment, and rulemaking. Interestingly there is a significant spectrum of approaches, methods, programs, controls, data bases, and standards. The quest of many is to assimilate the full compliment of PSA and RIDM information and to achieve a balanced international harmony. The goal is to focus the best of the best, so to speak, for the benefit of all. Accordingly, this presentation will address the principles, benefits, and applications of RIDM. It will also address some of the challenges and areas to improve. Finally it will highlight efforts by the IAEA and others to capture the international thinking, experience, successes, challenges, and lessons in RIDM. (authors)

  10. Application of reliability techniques to prioritize BWR [boiling water reactor] recirculation loop welds for in-service inspection

    International Nuclear Information System (INIS)

    Holman, G.S.

    1989-12-01

    In January 1988 the US Nuclear Regulatory Commission issued Generic Letter 88-01 together with NUREG-0313, Revision 2, ''Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping,'' to implement NRC long-range plans for addressing the problem of stress corrosion cracking in boiling water reactor piping. NUREG-0313 presents guidelines for categorizing BWR pipe welds according to their SCC condition (e.g., presence of known cracks, implementation of measures for mitigating SCC) as well as recommended inspection schedules (e.g., percentage of welds inspected, inspection frequency) for each weld category. NUREG-0313 does not, however, specify individual welds to be inspected. To address this issue, the Lawrence Livermore National Laboratory developed two recommended inspection samples for welds in a typical BWR recirculation loop. Using a probabilistic fracture mechanics model, LLNL prioritized loop welds on the basis of estimated leak probabilities. The results of this evaluation indicate that riser welds and bypass welds should be given priority attention over other welds. Larger-diameter welds as a group can be considered of secondary importance compared to riser and bypass welds. A ''blind'' comparison between the probability-based inspection samples and data from actual field inspections indicated that the probabilistic analysis generally captured the welds which the field inspections identified as warranting repair or replacement. Discrepancies between the field data and the analytic results can likely be attributed to simplifying assumptions made in the analysis. The overall agreement between analysis and field experience suggests that reliability techniques -- when combined with historical experience -- represent a sound technical basis on which to define meaningful weld inspection programs. 13 refs., 8 figs., 5 tabs

  11. Overview of improvements in work practices and instrumentation for CANDU primary heat transport feeders in-service inspections

    Energy Technology Data Exchange (ETDEWEB)

    Marcotte, O., E-mail: olivier@nucleom.ca [Nucleom Inc., Quebec, Quebec (Canada); Rousseau, G., E-mail: rousseau.gilles.a@hydro.qc.ca [Hydro Quebec, Becancour, Quebec (Canada); Rochefort, E., E-mail: erochfort@zetec.com [Zetec Canada, Quebec, Quebec (Canada)

    2013-01-15

    The Canadian nuclear industry has developed many advanced non-destructive inspection techniques to be applied safely in hazardous environments in recent years. Automated systems, manual tooling and specialized software modules have been designed since early 2000s to provide complete and very efficient fitness for service inspection of primary heat transport system carbon steel feeder pipes. These techniques deal with complex geometries, difficult access and, radioactive environment. Complementary NDE techniques, namely Ultrasounds, eddy current, phased-array UT and automated scanners are used. This presentation describes the improvements in inspection practices and the advanced data analysis features. (author)

  12. Development and trial application of risk information

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    JNES has been doing various activities to stimulate the introduction of Risk Informed Regulation (RIR) to the safety regulation of nuclear power plants (NPPs) in Japan. Some applications are already incorporated, such as the regulatory review of Maintenance Programs and Safety Significance Evaluation for Inspection Findings. In consideration with the experience of the accident in Fukushima Daiichi Nuclear Power Station, JNES addressed development of regulatory guidelines, evaluation of the current condition of Fukushima Daiichi Nuclear Power Station, evaluation of effectiveness of severe accident management measures with the backgrounds of insights and experiences on probabilistic risk assessment (PRA) and RIR. Especially, the experiences were applied to the development of the methodologies for evaluation of effectiveness of severe accident managements. As for inspection and operation of NPPs, JNES enhanced the PRA scope applied to the importance analysis for Maintenance Program, SDP and RI-ISI in consideration with the insights of RIR in Japan and other countries. (author)

  13. An ultrasonic methodology for in-service inspection of shell weld of core support structure in a sodium cooled fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Anish, E-mail: anish@igcar.gov.in; Rajkumar, K.V.; Sharma, Govind K.; Dhayalan, R.; Jayakumar, T.

    2015-02-15

    Highlights: • We demonstrate a novel ultrasonic methodology for in-service inspection of shell weld of core support structure in a sodium cooled fast breeder reactor. • The methodology comprises of the inspection of shell weld immersed in sodium from the outside surface of the main vessel using ultrasonic guided wave. • The formation and propagation of guided wave modes are validated by finite element simulation of the inspection methodology. • A defect down to 20% of 30 mm thick wall (∼6 mm) in the shell weld can be detected reliably using the developed methodology. - Abstract: The paper presents a novel ultrasonic methodology developed for in-service inspection (ISI) of shell weld of core support structure of main vessel of 500 MWe prototype fast breeder reactor (PFBR). The methodology comprises of the inspection of shell weld immersed in sodium from the outsider surface of the main vessel using a normal beam longitudinal wave ultrasonic transducer. Because of the presence of curvature in the knuckle region of the main vessel, the normal beam longitudinal wave enters the support shell plate at an angle and forms the guided waves by mode conversion and multiple reflections from the boundaries of the shell plate. Hence, this methodology can be used to detect defects in the shell weld of the core support structure. The successful demonstration of the methodology on a mock-up sector made of stainless steel indicated that an artificial defect down to 20% of 30 mm thick wall (∼6 mm) in the shell weld can be detected reliably.

  14. In service inspection of the reactor pressure vessel coolant and moderator nozzles at Atucha 1. 1998/1999 outages

    International Nuclear Information System (INIS)

    Antonaccio, Carlos; Conde, Alberto; Fittipaldi, Andres H.; Maniotti, Jorge; Moliterno, Gabriel E.

    2000-01-01

    During the August 1998 and the August 1999 Atucha 1 outages, two areas were inspected on the Reactor Pressure Vessel: the nozzle inner radii and the nozzle shell welds on all 3 moderator nozzles and all 4 main coolant nozzles. The inspections themselves were carried out by Mitsui Babcock Energy Limited from Scotland. The coordination, maintenance assistant and mounting of the manipulator devices over the nozzles were carried out by NASA personnel. Although it was not the first time the nozzle shell welds were inspected, due to the technologies advances in the ultrasonic field and in the inspection manipulators (magnetic ones), it was possible to inspect more volume than in previous inspections. In the other hand, it was the first time NASA was able to inspect the inner radii. In this last case the mayor problems to inspect them were the nozzles geometry and the small space available to install manipulators. The result of the inspections were: 1) There were no reportable indications at any of the inner radii inspected; 2) The inspection of nozzle to shell welds in main-coolant nozzles R3 and R4 detected flaws (one in each nozzle) which were reported as exceeding the dimensions specified as the acceptance level under Table IWB 3512-1, Section XI of the ASME code. Subsequent analysis requested by NASA and performed by Mitsui Babcock, demonstrated that the flaws were over dimensioned and could be explained as due to 'point' flaws. The analysis was based on theoretical mathematic model and experimental trials. Therefore their dimension were under the acceptance level of the ASME XI code. Although the Mitsui Babcock analysis, and at the same time it was in progress, it was assumed that the flaws were as they were originally presented (exceeding the acceptance level). NASA asked SIEMENS/KWU, the designer of the plant, to perform the fracture assessment according to ASME XI App. A. The assessment shows that the expected crack growth is negligibly small and the safety

  15. Periodical in-service inspection as part of individual program of quality assurance of steam generators and pressurizers of WWER 440 nuclear power plant

    International Nuclear Information System (INIS)

    Kawalec, M.

    1982-01-01

    The manufacturers of equipment for nuclear power plants in the Czechoslovak Socialist Republic are obligated to process so-called individual programs of quality assurance in order to secure the quality of selected equipment in nuclear power. These programmes should include the evaluation of the design of the individual equipments with regard to the implementation of in-service inspection. The main problems are discussed related to the processing of the program of quality assurance for the steam generator and pressurizer. To solve these problems it is necessary that the general project designer should make a classification of the components according to safety categories and that the manufacturers should determine the weak points of the design on the basis of an analysis of the design of individual component nodes. On the basis of such an analysis it is then necessary to evaluate the existing design of the scale of in-service inspections and to decide whether or not new inspection methods should be added. (Z.M.)

  16. Integration of in-service inspection works in the objectives of nuclear power plants; Integracion de los trabajos de inspeccion en servicio en los objectivos de las centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M.; Lopez, M.A.

    1996-09-01

    The present articles summarizes the objectives of Spanish NPPs and the in-service inspection aspect in these objectives. The Safety maintenance, lifetime of nuclear power plants, reduction of doses and wastes and the participation of main are evaluated.

  17. Design considerations, tooling, and equipment for remote in-service inspection of radioactive piping and pressure-vessel systems

    International Nuclear Information System (INIS)

    Swannack, D.L.; Schmoker, D.S.

    1983-01-01

    This paper summarizes results obtained in use of remotely-operated nondestructive testing (NDT) equipment for inspection of reactor-system components. Experience obtained in operating the Fast Flux Test Facility (FFTF) has provided a basis for field verification of remote NDT equipment designs and has suggested development improvements. Remote Viewing and data gathering systems used include periscopes, borescopes, fiberscopes, hybrid borescopes/fiberscopes, and closed circuit television. A summary of design consideration for inspection equipment and power plant design is presented to achieve improved equipment operation and reduction of plant maintenance downtime

  18. Present activity in ASME Section XI regarding risk-informed maintenance

    International Nuclear Information System (INIS)

    Hedden, Owen; Chockie, Alan

    2005-01-01

    Since 1996 Section XI of the ASME Boiler and Pressure Vessel Code has actively incorporated risk-informed concepts. The risk-informed process provides a framework for allocating inspection resources in a cost-effective manner and helps focus inspections where most critical for plant safety. Based on the success of the risk-informed ISI piping applications at US and non-US plants, Section XI has refined existing Code Cases and expanded the use of the risk-informed process to a variety of high-risk components and systems. The risk informed approach started in the area of inspection and is now being expanded to other plant maintenance activities. This article summarizes the Section XI actions and the continued development of the risk-informed process to improve nuclear plant maintenance. (author)

  19. Integrated Risk Information System (IRIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — EPA?s Integrated Risk Information System (IRIS) is a compilation of electronic reports on specific substances found in the environment and their potential to cause...

  20. Developments for the ultrasonic in-service inspection of the inner near surface zone of circular welds in the vessel of the fast breeder-reactor SNR 300

    International Nuclear Information System (INIS)

    Salzburger, H.J.; Huebschen, G.; Neuschwander, R.; Kleffner, G.; Wessels, J.

    1990-01-01

    For in-service, ultrasonic inspection of the inner near-surface zone of the welds 1 and 6 of the vessel of the SNR-300, an automated system has been developed for scanning, manipulation and evaluation tasks. The scanning system which currently is tested and qualified as a prototype system uses heat-resistant EMUS probes which do not require coupling agents, and which have been optimized for three different testing tasks. The required electronic equipment has also been developed to prototype stage, and both have been incorporated into the automated manipulation, data acquisition and evaluation system. (orig.) [de

  1. Development, design, construction and testing of pumps, intermediate heat exchangers and manipulator systems for in-service inspection of SNR 300

    International Nuclear Information System (INIS)

    Vroom, J.P.; Heslenfeld, M.W.; Westerweele, W.J.; Willigen, A. van

    1978-01-01

    The first part of this paper reviews the development, design, construction and testing of sodium pumps and intermediate heat exchangers as carried out by NERATOOM in the Netherlands. Testing of full-size components under operational conditions yielded important information for the design of the components for SNR 300. Information is also given in brief on the manufacture of the components. The second part reviews the work done on manipulator systems for in-service inspection as carried out by INTERATOM in Germany. In this field again experience gained from tests had important consequences for the design of the apparatus for SNR 300. (author)

  2. Study on the ultrasonic inspection method using the full matrix capture for the in service railway wheel

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Jianping; Wang, Li; Zhang, Yu; Gao, Xiaorong; Wang, Zeyong; Peng, Chaoyong [NDT Research Center, School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031 (China)

    2014-02-18

    The quality of wheel is especially important for the safety of high speed railway. In this paper, a new ultrasonic array inspection method, the Full Matrix Capture (FMC) has been studied and applied to the high speed railway wheel inspection, especially in the wheel web from the tread. Firstly, the principle of FMC and TFM algorithm is discussed, and then the new optimization is applied to the standard FMC; Secondly the fundamentals of optimization is described in detail and the performance is analyzed. Finally, the experiment has been built with a standard phased array block and railway wheel, and then the testing results are discussed and analyzed. It is demonstrated that this change for the ultrasonic data acquisition and image reconstruction has higher efficiency and lower cost comparing to the FMC's procedure.

  3. Opinion on the demonstration of the 900 MWe reactor vessels in-service behaviour after their third decennial inspection

    International Nuclear Information System (INIS)

    2010-01-01

    In this report, an expert group comments and assesses how sufficient are the demonstration and the actions performed by EDF to justify the in-service behaviour of nuclear reactor vessels. More precisely, it comments and discusses the different steps of the EDF demonstration: follow-up of the fluence received by the vessels, identification of the most severe transients and thermodynamic calculations, behaviour of irradiated materials, mechanical analysis, in-service control and follow-up plan, ageing management. Recommendations are then formulated

  4. Secondary side corrosion in steam generator tubes: lessons learned in France from the in-service inspection results

    International Nuclear Information System (INIS)

    Comby, R.

    1997-01-01

    Non-destructive testing (NDT) has proved to be very important in the maintenance of steam generator tubing. This is particularly true in the case of secondary side corrosion, because this type of degradation leads to various morphologies which are often complex (intergranular attack) (IGA), intergranular stress corrosion cracking (IGSCC), or a mixture of both. Their detection and characterization by the usual NDT techniques have been achieved through numerous laboratory studies, which were conducted in order to determine the performance and limitations of NDT. Pulled tube examination in a hot laboratory was very valuable, for both NDT and fracture mechanics aspects. The eddy current bobbin coil probe, used for multipurpose inspection of tubes, allows the detection of IGA-SCC at the tube support plate elevation. In France, the use of rotating probes is not required for that type of degradation, since the repair criterion is based on bobbin coil results only. The bobbin coil is also used for detection of IGSCC occurring in free spans, within sludge deposits. The eddy current rotating probe allows, in that case, characterization of main cracks. Concerning the outer diameter initiated circumferential cracks which occur at the top of the tube sheet, only the rotating probe is used. An ultrasonic (UT) inspection was performed several times, in order to obtain information on UT capabilities. The goal of tube inspection is obviously knowledge of the status of steam generators, but also to follow up degradations and to estimate their revolution, and to verify the beneficial effect of some corrective measures, e.g. boric acid injection. (orig.)

  5. Development of technology for the in-service inspection of reactor pressure vessel metal condition using a magnetic method

    International Nuclear Information System (INIS)

    Bakirov, M. B.; Zabruskov, N.Y; Massoud, J.P.

    2002-01-01

    The opportunity to perform the inspection of condition of base metal and metal of welded joints of cladded vessels of PWR by non destructive methods is shown. The technique for on-site specimen-free testing is offered on the basis of sharing a kinetic hardness method and magnetic method. The results of studies of magnetic and mechanical properties of vessel steels in various condition after irradiation and thermal processing are submitted. It is shown, that the magnetic properties (first of all coercive force) are sensitive to change of structure of a material. (authors)

  6. Application of non-destructive testing and in-service inspection to research reactors. Results of a co-ordinated research project

    International Nuclear Information System (INIS)

    2001-12-01

    -destructive testing (NDT), are generally called in-service inspections (ISI) and, together with the above specific techniques, are the subject of the present TECDOC. The main objectives of the TECDOC are to present a number of these special techniques and to give guidance for their application. The guidance and recommendations given in this publication form the basis for the conduct of ISI of research reactors with limited hazard potential to the public. This TECDOC is based on the results of a Co-ordinated Research Project (CRP) on the Application of Non-destructive Testing and In-service Inspection to Research Reactors that the IAEA organized in 1995 to supplement its activities on research reactor ageing within its Research Reactor Safety Programme (RRSP). Because of the importance of such in-service inspections within the programmes for the management of ageing in research reactors, this TECDOC will be useful to a large fraction of the currently operating research reactors that are over 30 years old

  7. Analysis of in-service inspection guides for post-tensioning systems in containment structures with greased tendons

    International Nuclear Information System (INIS)

    Bae, I. H.; Choi, I. G.; Seo, J. M.

    2000-01-01

    Prestressed concrete containments(PCC) are inspected periodically to ensure structural integrity and to identify and correct problems before they come critical. These inspections are conducted in accordance with the Nuclear Regulatory Committee(NRC) Regulatory Guide. As experience with the surveillance mounts, the guide is revised to keep pace with technological advances in containment design and to reflect the knowledge obtained experience. In the study, an analysis of the available utility surveillance data and an evaluation of the NRC Regulatory Guide and the ASME Code are conducted. The results indicate that the average value of the lower bound defined in Regulatory Guide 1.35.1 can be less than the minimum required force level at 40 years for the existing containment and thus an acceptable alternative has to be presented to meet the allowance of the guide. Tendons in excess of the upper bound or 70% of the ultimate tensile strength of the tendon are observed. Such an occurrence indicates tendon behavior outside the tolerance band that expected, and the cause of such behavior has to be investigated. It is shown that the behavior of the predicted prestressing force with time based on assumed losses does quite different from that of the measured tendon force with time and, therefore, studies for the significant factors, such as shrinkage and creep of concrete, that influence the time-dependent losses in PCC are needed. Additional research on the long-term effects of the impurity levels on the effectiveness of the grease seems justified

  8. Inspection qualification and implementation of ENIQ in Sweden

    International Nuclear Information System (INIS)

    Zettervall, Tommy

    2013-01-01

    Many countries are currently considering their approaches to inspection qualification and risk-informed in-service inspection (RI-ISI) and are carefully assessing experience data. In Europe most of the utilities operating nuclear power plants have joined together to form the European Network for Inspection Qualification ENIQ. In practice, qualification can be performed with varying degrees of complexity and cost, varying from capability statement based on existing evidence, through to an extensive qualification consisting of a detailed Technical Justification (TJ) together with open and blind trials on full-scale test blocks. An Inspection Qualification is an investigation and demonstration, which confirm that an inspection system has the ability to solve its specific tasks. The qualification is a Quality Assurance of an inspection system based on documents and practical trials. A reliable inspection system, based on a reliable qualification and correct prerequisites, will reduce total costs for Licensees and increase the credibility of the inspection result. To get such inspection system, which could be valid for many years, it's of necessity to fulfil all included parts in the process. It begins with the Technical Specification from Licensee, where input data and requirements about the actual component are specified. To get an inspection system that could live over time, the Technical Justification is of importance. Finally the test blocks and used simulation techniques play an important part of the final result, and these test blocks together with TJ form the basis for qualification body's decision. (author)

  9. Evaluation of piping reliability and failure data for use in risk-based inspections of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, V. de; Soares, W.A.; Costa, A.C.L. da; Rabello, E.G.; Marques, R.O., E-mail: vasconv@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2016-07-01

    During operation of industrial facilities, components and systems can deteriorate over time, thus increasing the possibility of accidents. Risk-Based Inspection (RBI) involves inspection planning based on information about risks, through assessing of probability and consequence of failures. In-service inspections are used in nuclear power plants, in order to ensure reliable and safe operation. Traditional deterministic inspection approaches investigate generic degradation mechanisms on all systems. However, operating experience indicates that degradation occurs where there are favorable conditions for developing a specific mechanism. Inspections should be prioritized at these places. Risk-Informed In-service Inspections (RI-ISI) are types of RBI that use Probabilistic Safety Assessment results, increasing reliability and plant safety, and reducing radiation exposure. These assessments use both available generic reliability and failure data, as well as plant specific information. This paper proposes a method for evaluating piping reliability and failure data important for RI-ISI programs, as well as the techniques involved. (author)

  10. Evaluation of piping reliability and failure data for use in risk-based inspections of nuclear power plants

    International Nuclear Information System (INIS)

    Vasconcelos, V. de; Soares, W.A.; Costa, A.C.L. da; Rabello, E.G.; Marques, R.O.

    2016-01-01

    During operation of industrial facilities, components and systems can deteriorate over time, thus increasing the possibility of accidents. Risk-Based Inspection (RBI) involves inspection planning based on information about risks, through assessing of probability and consequence of failures. In-service inspections are used in nuclear power plants, in order to ensure reliable and safe operation. Traditional deterministic inspection approaches investigate generic degradation mechanisms on all systems. However, operating experience indicates that degradation occurs where there are favorable conditions for developing a specific mechanism. Inspections should be prioritized at these places. Risk-Informed In-service Inspections (RI-ISI) are types of RBI that use Probabilistic Safety Assessment results, increasing reliability and plant safety, and reducing radiation exposure. These assessments use both available generic reliability and failure data, as well as plant specific information. This paper proposes a method for evaluating piping reliability and failure data important for RI-ISI programs, as well as the techniques involved. (author)

  11. After-production and in-service inspections of components of nuclear power plant primary coolant circuits

    International Nuclear Information System (INIS)

    Slama, K.; Svetlik, M.

    1990-01-01

    A new diagnostic system was developed for detecting defects in the material of mechanically loaded equipment. It is based on the measurement of elastic strain waves propagating through the materials. The instrument units as well as the methodology and software are of Czechoslovak origin and can be modified to conform to the requirements and experience of the user. The way of applying the method to the diagnostics of pressure vessels, main circulation pumps of the pressurizers and of the primary piping is described. Some results of after-production and in-service acoustic emission tests are given, as are the technical parameters of the acoustic emission analyzer. (M.D.). 5 figs

  12. Evolution in the design and development of the in-service inspection device for the Indian 500 MWe Fast Breeder Reactor

    International Nuclear Information System (INIS)

    Singh, Ashutosh Pratap; Rajagopalan, C.; Rakesh, V.; Rajendran, S.; Venugopal, S.; Kasiviswanathan, K.V.; Jayakumar, T.

    2011-01-01

    Highlights: → Conceptual study on the configuration of an ISI device for FBR interspace environment has been carried out. → Prototyping of the concept has been experimentally validated in a mock up. → High temperature version of the ISI device has been made and tested in mock-up. Further experimentation is underway. → Simulation of different configurations of the device has been carried out with respect to reduced gap between main vessel and safety vessel for future FBRs. → Studies on wheel lining for the device have been carried out at 150 o C for better traction and payload capability. - Abstract: In-service inspection (ISI) plays a major role in monitoring the condition of nuclear power plant structures and components. Based on the information gathered during inspection and the studies carried out, it is possible to assess the extent of damage and take corrective measures to keep effects of ageing under control. In nuclear power plants comprehensive ISI is dictated by issues of increased safety to personnel and equipment, and efficiently enhances the plant life. A special emphasis has been laid on the development of robotic devices for the ISI of the indigenous Indian 500 MWe Prototype Fast Breeder Reactor (FBR) components. This paper traces the experiments and simulations in the key developments of a robotic device, for the ISI of main vessel and safety vessel of FBRs, carried out at Indira Gandhi Centre for Atomic Research, India.

  13. Qualification of NDT techniques for in-service inspections in nuclear power plants in accordance with ENIQ - examples and lessons - learned

    International Nuclear Information System (INIS)

    Just, T.; Csapo, G.

    2006-01-01

    ENIQ (European Network for Inspection and Qualification) has developed regulations on how to qualify non-destructive testing (NDT) methods and techniques in a standardized and structured manner. Two major innovative qualifications were carried out and reviewed with regard to implementation, according to the recommended German practice of ENIQ. The conclusions were drawn after performing the ENIQ qualification procedure for in-service inspections (ISI) of real components in nuclear power plants (NPP). The first example covers the qualification of NDT methods for the detection and characterization of surface, subsurface and underclad cracks in the area of the austenitic cladded RPV surface. Open and blind tests were conducted applying UT and ET (from the ID) and UT (from the OD) on realistic flaws (artificially induced IGSCC, hot cracks and fatigue cracks) in the cladding of a full scale RPV mock-up from MPA Stuttgart. The second example covers the qualification of mechanised RT in combination with tomography (developed by the BAM) for the sizing of cracks in pipe welds. For both qualification procedures TUEV NORD SysTec experts were part of the qualification body. The proposed NDT procedures have been qualified within defined limits of application. Recommendations were made to optimise the procedures and the techniques itself further. (orig.)

  14. Risk informed decision making - a pre-study

    International Nuclear Information System (INIS)

    Simola, K.; Pulkkinen, U.

    2004-04-01

    Examples of risk-informed decisions are establishing maintenance programmes, optimising inspection policies and justifying plant modifications, and revising technical specifications. Applications in daily situations can be such as accepting or rejecting exemptions from technical specifications. The aim of this pre-study was to identify the status of risk-informed decision making at Swedish and Finnish nuclear power plants and nuclear safety authorities. Responses to a questionnaire were obtained either by interviews or by e-mail from two Swedish and two Finnish NPPs, SKI and STUK. The development of a risk-informed decision procedure based on decision analytic ideas is worth recommending. A clear documentation format is a part of such procedure. In order to serve as a basis for final decision, the documentation should include clearly defined decision criteria, qualification of PSA model for the issue under analysis, description of most important uncertainties and assumptions. (au)

  15. Risk-informed prediction of feeder end of life

    International Nuclear Information System (INIS)

    Jyrkama, M.; Pandey, M.

    2011-01-01

    The operating life of feeder piping is negatively impacted by flow accelerated corrosion (FAC). In this study, an assessment of a large set of inspection data reveals that FAC in feeders is a relatively stationary process, with variability only at the local scale. Given the added uncertainty from inspection coverage, a new method for estimating the thinning rate and feeder EOL is developed using a probabilistic approach. The results of the study illustrate the benefits of the methodology in supporting risk-informed decision making at the station by quantifying the present and incremental risk in the feeder system over time. (author)

  16. Risk-informed prediction of feeder end of life

    Energy Technology Data Exchange (ETDEWEB)

    Jyrkama, M.; Pandey, M. [Univ. of Waterloo, Ontario (Canada)

    2011-07-01

    The operating life of feeder piping is negatively impacted by flow accelerated corrosion (FAC). In this study, an assessment of a large set of inspection data reveals that FAC in feeders is a relatively stationary process, with variability only at the local scale. Given the added uncertainty from inspection coverage, a new method for estimating the thinning rate and feeder EOL is developed using a probabilistic approach. The results of the study illustrate the benefits of the methodology in supporting risk-informed decision making at the station by quantifying the present and incremental risk in the feeder system over time. (author)

  17. Automated ultrasonic testing of nuclear reactor welds and overlays in pre-service and in-service inspections

    International Nuclear Information System (INIS)

    Sladky, J.

    1988-01-01

    Since 1982, automatic pre-service and in-service checks are being made of welded joints and overlays on pressure vessels of WWER-440 nuclear reactors in Czechoslovakia. This is being done using the SKODA REACTORTEST TRC facility which is used for checking peripheral welded joints on the pressure vessel, neck joints, overlays in other selected areas of the cylindrical section of the pressure vessel, on radius transitions of the pressure vessel and of necks, and on the cylindrical part of necks, and also for checking the base material in selected parts of the pressure vessel and the base material of the neck extension piece. The tests are of two types, namely tests of peripheral welds and overlays of the cylindrical parts of the pressure vessel, and tests of the necks. Different ultrasonic probe holders are used for the tests, with totally different design. Ultrasonic probes which were initially used were of foreign make while at present, those of Czechoslovak make are used. For each pressure vessel a set of ultrasonic probes is used which should suffice for the life of the vessel. Experience gained so far is being used in work on the project of a new device for testing nuclear reactor presure vessels from the inside. (Z.M.)

  18. Development of a Versatile Ultrasonic Internal Pipe/Vessel Component Monitor for In-Service Inspection of Nuclear Reactor Components

    Energy Technology Data Exchange (ETDEWEB)

    Searfass, Clifford T. [Structural Integrity Associates, Inc., State College, PA (United States); Malinowski, Owen M. [Structural Integrity Associates, Inc., State College, PA (United States); Van Velsor, Jason K. [Structural Integrity Associates, Inc., State College, PA (United States)

    2015-03-22

    The stated goal of this work was to develop a versatile system which could accurately measure vessel and valve internal vibrations and cavitation formation under in-service conditions in nuclear power plants, ultrasonically. The developed technology will benefit the nuclear power generation industry by allowing plant operators to monitor valve and vessel internals during operation. This will help reduce planned outages and plant component failures. During the course of this work, Structural Integrity Associates, Inc. gathered information from industry experts that target vibration amplitudes to be detected should be in the range of 0.001-in to 0.005-in (0.025-mm to 0.127-mm) and target vibration frequency ranges which should be detected were found to be between 0-Hz and 300-Hz. During the performed work, an ultrasonic measuring system was developed which utilized ultrasonic pulse-echo time-of-flight measurements to measure vibration frequency and amplitude. The developed system has been shown to be able to measure vibration amplitudes as low as 0.0008-in (0.020-mm) with vibration frequencies in the range of 17-Hz to 1000-Hz. Therefore, the developed system was able to meet the industry needs for vibration measurement. The developed ultrasonic system was also to be able to measure cavitation formation by monitoring the received ultrasonic time- and frequency-domain signals. This work also demonstrated the survivability of commercially available probes at temperatures up to 300-F for several weeks.

  19. Communicating risk information and warnings

    Science.gov (United States)

    Mileti, D. S.

    1990-01-01

    Major advances have occurred over the last 20 years about how to effectively communicate risk information and warnings to the public. These lessons have been hard won. Knowledge has mounted on the finding from social scientific studies of risk communication failures, successes and those which fell somewhere in between. Moreover, the last 2 decades have borne witness to the brith, cultivation, and blossoming of information sharing between those physical scientists who discover new information about risk and those communcation scientists who trace its diffusion and then measure pbulic reaction. 

  20. Air Risk Information Support Center

    Energy Technology Data Exchange (ETDEWEB)

    Shoaf, C.R.; Guth, D.J. [Environmental Protection Agency, Washington, DC (United States)

    1990-12-31

    The Air Risk Information Support Center (Air RISC) was initiated in early 1988 by the US Environmental Protection Agency`s (EPA) Office of Health and Environmental Assessment (OHEA) and the Office of Air Quality Planning and Standards (OAQPS) as a technology transfer effort that would focus on providing information to state and local environmental agencies and to EPA Regional Offices in the areas of health, risk, and exposure assessment for toxic air pollutants. Technical information is fostered and disseminated by Air RISCs three primary activities: (1) a {open_quotes}hotline{close_quotes}, (2) quick turn-around technical assistance projects, and (3) general technical guidance projects. 1 ref., 2 figs.

  1. Integrated risk information system (IRIS)

    Energy Technology Data Exchange (ETDEWEB)

    Tuxen, L. [Environmental Protection Agency, Washington, DC (United States)

    1990-12-31

    The Integrated Risk Information System (IRIS) is an electronic information system developed by the US Environmental Protection Agency (EPA) containing information related to health risk assessment. IRIS is the Agency`s primary vehicle for communication of chronic health hazard information that represents Agency consensus following comprehensive review by intra-Agency work groups. The original purpose for developing IRIS was to provide guidance to EPA personnel in making risk management decisions. This original purpose for developing IRIS was to guidance to EPA personnel in making risk management decisions. This role has expanded and evolved with wider access and use of the system. IRIS contains chemical-specific information in summary format for approximately 500 chemicals. IRIS is available to the general public on the National Library of Medicine`s Toxicology Data Network (TOXNET) and on diskettes through the National Technical Information Service (NTIS).

  2. To the application of TV and optical equipment for in-service inspection of reactor vessel and primary circuit component materials

    International Nuclear Information System (INIS)

    Afonin, Eh.M.; Bachelis, I.M.; Tokarev, E.A.; Yastrebov, V.E.

    1985-01-01

    Some problems of application of TV and optical equipment for inspection of reactor vessel and primary circuit component materials are considered taking the most widespread WWER-440 type reactor as an example. The most advanrageous objects of the inspection and typical zones of equipment arrangement are shown. Methods and peculiarities of the inspection with the use of TV and optical equipment are presented. Recommendations on rational application of the equipment for the inspection of WWER-440 reactor vessel components are given

  3. Preventive and Predictive Maintenance, Warehousing of Spares, Periodic Testing and In-Service Inspection Activities at the Nigerian Research Reactor-1 Facility

    Energy Technology Data Exchange (ETDEWEB)

    Yusuf, I.; Mati, A. A.; Dewu, B. B.M., [Centre for Energy Research and Training, Ahmadu Bello University, Zaria (Nigeria)

    2014-08-15

    The Nigerian Research Reactor–1, or NIRR-1, is sited at Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. Activities on preventive or routine maintenance have been institutionalized since the commissioning of the reactor in February 2004. This has grossly reduced the rates of corrective maintenance activities and helped the reactor management a great deal in predicting failure rates of reactor components and other auxiliary units. Routine maintenance of systems and components are being carried out on a weekly, quarterly and annual basis based on manufacturer’s recommendations, which have been reviewed and improved over the years. The paper presents the implementation of maintenance activities in NIRR-1 from its initial criticality in 2004 till today and the new scheme for periodic testing and in-service-inspection developed after an IAEA Integrated Safety Assessment of Research Reactors mission. The measures put in place are envisaged to reduce the negative impact of ageing on NIRR-1 and its auxiliary systems. (author)

  4. Risk-based inspection in the context of nuclear power plants

    International Nuclear Information System (INIS)

    Soares, Wellington A.; Vasconcelos, Vanderley de; Rabello, Emerson G.

    2015-01-01

    Nuclear power plant owners have to consider several aspects like safety, availability, costs and radiation exposure during operation of nuclear power plants. They also need to demonstrate to regulatory bodies that risk assessment and inspection planning processes are being implemented in effective and appropriate manner. Risk-Based Inspection (RBI) is a methodology that, unlike time-based inspection, involves a quantitative assessment of both failure probability and consequence associated with each safety-related item. A correctly implemented RBI program classifies individual equipment by its risks and prioritizes inspection efforts based on this classification. While in traditional deterministic approach, the inspection frequencies are constant, in the RBI approach the inspection interval for each item depends on the risk level. Regularly, inspection intervals from RBI result in risk levels lower or equal than deterministic inspection intervals. According to the literature, RBI solutions improve integrity and reduce costs through a more effective inspection. Risk-Informed In-service Inspection (RI-ISI) is the equivalent term used in the nuclear area. Its use in nuclear power plants around world is briefly reviewed in this paper. Identification of practice methodologies for performing risk-based analyses presented in this paper can help both Brazilian nuclear power plant operator and regulatory body in evaluating the RI-ISI technique feasibility as a tool for optimizing inspections within nuclear plants. (author)

  5. Risk-based inspection in the context of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Wellington A.; Vasconcelos, Vanderley de; Rabello, Emerson G., E-mail: soaresw@cdtn.br, E-mail: vasconv@cdtn.br, E-mail: egr@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    Nuclear power plant owners have to consider several aspects like safety, availability, costs and radiation exposure during operation of nuclear power plants. They also need to demonstrate to regulatory bodies that risk assessment and inspection planning processes are being implemented in effective and appropriate manner. Risk-Based Inspection (RBI) is a methodology that, unlike time-based inspection, involves a quantitative assessment of both failure probability and consequence associated with each safety-related item. A correctly implemented RBI program classifies individual equipment by its risks and prioritizes inspection efforts based on this classification. While in traditional deterministic approach, the inspection frequencies are constant, in the RBI approach the inspection interval for each item depends on the risk level. Regularly, inspection intervals from RBI result in risk levels lower or equal than deterministic inspection intervals. According to the literature, RBI solutions improve integrity and reduce costs through a more effective inspection. Risk-Informed In-service Inspection (RI-ISI) is the equivalent term used in the nuclear area. Its use in nuclear power plants around world is briefly reviewed in this paper. Identification of practice methodologies for performing risk-based analyses presented in this paper can help both Brazilian nuclear power plant operator and regulatory body in evaluating the RI-ISI technique feasibility as a tool for optimizing inspections within nuclear plants. (author)

  6. Implementing risk-informed life-cycle design

    International Nuclear Information System (INIS)

    Hill, Ralph S. III

    2007-01-01

    This paper describes a design process based on risk-informed probabilistic methodologies that cover a facility's life-cycle from start of conceptual design through decontamination and decommissioning. The concept uses probabilistic risk assessments to identify target reliabilities for facility systems and components. Target reliabilities are used in system and subsystem simulation analyses to determine the optimum combination of initial system and component construction reliability, maintenance frequency, and inspection frequency for both active and passive components. The target reliabilities are also used for system based code margin exchange to reduce excessive level of margins to appropriate levels resulting in a more flexible structure of codes and standards that improves facility reliability and cost. The paper includes a description of a risk informed life-cycle design process, a summary of work being done, and a discussion of work needed to implement the process. (author)

  7. PRA and Risk Informed Analysis

    International Nuclear Information System (INIS)

    Bernsen, Sidney A.; Simonen, Fredric A.; Balkey, Kenneth R.

    2006-01-01

    The Boiler and Pressure Vessel Code (BPVC) of the American Society of Mechanical Engineers (ASME) has introduced a risk based approach into Section XI that covers Rules for Inservice Inspection of Nuclear Power Plant Components. The risk based approach requires application of the probabilistic risk assessments (PRA). Because no industry consensus standard existed for PRAs, ASME has developed a standard to evaluate the quality level of an available PRA needed to support a given risk based application. The paper describes the PRA standard, Section XI application of PRAs, and plans for broader applications of PRAs to other ASME nuclear codes and standards. The paper addresses several specific topics of interest to Section XI. Important consideration are special methods (surrogate components) used to overcome the lack of PRA treatments of passive components in PRAs. The approach allows calculations of conditional core damage probabilities both for component failures that cause initiating events and failures in standby systems that decrease the availability of these systems. The paper relates the explicit risk based methods of the new Section XI code cases to the implicit consideration of risk used in the development of Section XI. Other topics include the needed interactions of ISI engineers, plant operating staff, PRA specialists, and members of expert panels that review the risk based programs

  8. A Life-Cycle Risk-Informed Systems Structured Nuclear Code

    International Nuclear Information System (INIS)

    Hill, Ralph S. III

    2002-01-01

    Current American Society of Mechanical Engineers (ASME) nuclear codes and standards rely primarily on deterministic and mechanistic approaches to design. The design code is a separate volume from the code for inservice inspections and both are separate from the standards for operations and maintenance. The ASME code for inservice inspections and code for nuclear plant operations and maintenance have adopted risk-informed methodologies for inservice inspection, preventive maintenance, and repair and replacement decisions. The American Institute of Steel Construction and the American Concrete Institute have incorporated risk-informed probabilistic methodologies into their design codes. It is proposed that the ASME nuclear code should undergo a planned evolution that integrates the various nuclear codes and standards and adopts a risk-informed approach across a facility life-cycle - encompassing design, construction, operation, maintenance and closure. (author)

  9. The use of risk indicators for establishing inspection and control priorities

    International Nuclear Information System (INIS)

    Alzbutas, R.; Klimasauskas, A.; Nedzinskas, L.

    2003-01-01

    Risk-informed approach used to support decision-making related to in-service inspections was considered in order to identify ways for establishing inspection and control priorities. The in-service inspection of piping in the Ignalina NPP has been selected as the object for research application, The inspection process studied was modelled using the integration of deterministic and probabilistic analysis methods, In order to optimize the inspection process, the focus was set on the highest risk measured as the conditional core damage frequency, It was produced by quantitatively estimated probabilities of different degradation states and conditional failure consequence probabilities, Comprehensive databases for calculation of such indicators (measures) were collected and analyzed, The failure statistical analysis as well as the evaluation of inspection efficiency expressed by the probability of defect detection was also used, The databases were further investigated with a closer attention to the data variation and comparison of risk measures using the developed software, The developed software was used to perform and administrate all the risk evaluations and ensure the possibilities to compare different options and perform sensitivity analysis, The risk measures helped to define an adequate inspection program and to focus inspections on the more important locations of the study systems, This approach allowed an optimisation of the inspection program while the probabilistic and fundamental deterministic safety requirements were maintained, The approaches to define an acceptable level of the inspection program were also considered. These approaches to define an acceptable risk were considered together with the means to reduce the number of inspection sites and the cumulative radiation exposure to the NPP inspection personnel with a reduction of overall risk, The investigated issues provided a good basis for drawing conclusions about the inspection priorities, to

  10. Issues and future directions of 'introduction of Risk Informed Regulation'

    International Nuclear Information System (INIS)

    2008-01-01

    In 2004, Nuclear Safety Commission of Japan (NSC) set up a taskforce for developing a scheme of Risk Informed Regulation (RIR) introduction, which had discussed various aspects of utilization of risk information in nuclear regulations. In the final report compiled in 2007, the taskforce identified the significance of RIR introduction from viewpoint of enhancement of rationality, consistency and transparency as well as appropriate allocation of regulatory resources in the nuclear safety regulation and major issues for the further promotion were as follows: NSC is to maintain the comprehensively promoting function of the RIR introduction with reviewing global trends and latest technological knowledge, regulatory bodies are to further enhance the RIR in inspection and operational area, utilities and industries are to utilize further risk information in their self-maintenance activities and to gather trouble information data, academic societies are to establish the standards for risk evaluation technology and RIR, and research institutes are to carry out safety research and risk training for risk-communicators. This article presented summary of the final report aiming at upgrading safety regulation with enhancement of RIR introduction. (T. Tanaka)

  11. Experiences and future plan for risk-informed decision making in Korea

    International Nuclear Information System (INIS)

    Chung, D.W.; Ryu, Y.H.

    2001-01-01

    A program for establishing regulatory framework on the use of risk information has been underway since 1995, and several trial applications have been done to evaluate the applicability and usefulness of risk-informed approach to nuclear power plant regulation. The program consists of fifteen general and/or specific items of interest and pilot applications will be initiated in 2003. In parallel, research and development program has been continued to support the regulatory implementation. A task force team has been formed and the official channel has also been opened for cooperation between regulatory body and utility-related organizations. Specifically, a couple of trial applications have been done up to now. First, the risk-based inspection (RBI) program has been implemented to improve regulatory inspection framework by utilizing risk information obtained from plant specific PSA and worldwide operating experiences. Next, optimization of technical specifications has been applied for surveillance test intervals (STIs) and allowed outage time (AOT). (author)

  12. Report on probabilistic safety assessment (PSA) quality assurance in utilization of risk information

    International Nuclear Information System (INIS)

    2006-12-01

    Recently in Japan, introduction of nuclear safety regulations using risk information such as probabilistic safety assessment (PSA) has been considered and utilization of risk information in the rational and practical measures on safety assurance has made a progress to start with the operation or inspection area. The report compiled results of investigation and studies of PSA quality assurance in risk-informed activities in the USA. Relevant regulatory guide and standard review plan as well as issues and recommendations were reviewed for technical adequacy and advancement of probabilistic risk assessment technology in risk-informed decision making. Useful and important information to be referred as issues in PSA quality assurance was identified. (T. Tanaka)

  13. Study on in-service inspection and repair program and related plant design for Japan Sodium-Cooled Fast Reactor (JSFR)

    International Nuclear Information System (INIS)

    Kubo, Shigenobu; Suzuki, Shinichi; Kotake, Shoji; Nishiyama, Noboru; Uzawa, Masayuki

    2011-01-01

    Maintenance and repair program and conformity with them were investigated as a part of the conceptual design study of Japan Sodium-cooled Fast Reactor (JSFR). The maintenance program was set by taking the feature of sodium-cooled reactors and domestic practice of LWRs into account. Both of regulatory required inspection and voluntary inspection, which are conducted in the domestic LWRs, were counted. The regulatory required ISI program was based on that of the previous Japanese SFRs, LWRs (JSME S NA1) and liquid metal cooled reactors (ASME section XI division 3). Parts to be inspected, methods of inspection were identified for major structures and components. Concerning the repair program, we set three levels of repair requirements based on estimated frequency of defect and failure during the plant life time. For level 1, which might be occur several times during the plant life time, it is required to be easily repaired in a short period. Access routes and working space are considered in the component design and its arrangement. For level 2, which might be unlikely to occur during the plant life time, it is required to check that the repair work is feasible in a practical time range. For level 3, which frequency is negligible small, repair is not taken into account but the feasibility was investigated. The plant design shall be done so that all of above mentioned inspection and repair can be conducted. It is desired to ensure accessibility for all of the coolant and cover gas boundaries and the internal structures in order to cope with unforeseen troubles. Access routes for the reactor vessel and its internal structures, piping, pumps and intermediate heat exchangers and steam generators were investigated. As the results of that, possible ways for implementation of the maintenance and repair were identified. (author)

  14. Developments on ASME Code Cases to Risk-Informed Repair/Replacement Activities in Support of Risk-Informed Regulation Initiatives

    International Nuclear Information System (INIS)

    Balkey, Kenneth R.; Holston, William C.

    2002-01-01

    ASME Code Case N-658, 'Risk-Informed Safety Classification for Use in Risk-Informed Repair/Replacement Activities' and Code Case N-660, 'Alternative Repair/Replacement Requirements For Items Classified In Accordance With Risk-Informed Processes' are being completed to expand the breadth of risk-informed requirements for pressure-retaining items. This initiative, which is built from prior ASME Section XI risk-informed inservice inspection developments over the past decade, has been undertaken in conjunction with U.S. risk-informed regulation efforts. The U.S. Nuclear Regulatory Commission (NRC) is working with the industry on risk informing Title 10 Code of Federal Regulations Part 50 (10CFR50). The Nuclear Regulatory Commission's basic proposal is to allow modification of some of the special treatment requirements of 10CFR50. Their effort is proceeding via an Advanced Notice of Public Rulemaking, March 3, 2000, and an announcement of Availability of Draft Rule Wording, November 29, 2001, to add 10 CFR 50.69, 'Risk-Informed Treatment of Structures, Systems and Components'. A parallel task by the Nuclear Energy Institute (NEI) to develop a guideline on how to implement the results of the rulemaking is also well underway via NEI 00-04 (Draft Revision B), 'Option 2 Implementation Guideline', May 2001. This paper summarizes the content and status of approval of the proposed ASME Code Cases, including how they relate to the above NRC and NEI efforts. Some initial results from trial application of the Code Cases will also be cited. (authors)

  15. Use of risk information in regulatory reviews

    International Nuclear Information System (INIS)

    Sagar, B.; Benke, R.; Mohanty, S.

    2004-01-01

    The regulatory framework for licensing any high-level waste repository at Yucca Mountain in the United States, calls for appropriate use of risk information to ensure operational safety during the pre-closure period and long-term safety during the post-closure period. This paper focuses on the post-closure period. Regulations in the Code of Federal Regulations (CFR), Title 10, Part 63, apply to any repository at Yucca Mountain and envision use of probabilistic methods to develop quantitative risk information. Accumulated engineering and scientific experience at Yucca Mountain and analog sites and quantitative risk information from studies conducted by the implementer, regulator, and others are combined to formulate 'risk insights,' which are then used to plan and execute regulatory reviews. The U.S. Nuclear Regulatory Commission (NRC) and the Center for Nuclear Waste Regulatory Analyses (CNWRA) recently consolidated the knowledge gained during several g ears and developed such risk insights for the potential repository at Yucca Mountain. This paper discusses the types of risk information used to generate risk insights and how the risk insights will be used in regulatory reviews. A companion paper presents more details on sensitivity analysis methods used to generate risk information. (authors)

  16. Regulatory environment of transitioning to risk-informed regulations in U.S.A

    International Nuclear Information System (INIS)

    Choi, C. H.; Kim, C. H.

    1999-01-01

    With the publication of the PRA Policy Statement and recent regulatory guides, the U.S.NRC makes a continuous approach towards risk-informed regulations with the goal of establishing an overall framework for risk-informed decisions in all regulatory activities as well as plant specific licensing issues. Faced with the changing environment of deregulation of the electricity generation market, the licensee's effort to reduce design margins to enhance flexibility and to relieve unnecessary regulatory burdens have been focused on the control and reduction of plant operating costs. The risk-informed approach provides a structured, systematic, and defensible method that can be applied not only to rulemaking, but also to licensing, inspection, enforcement, and performance assessment, as well as provides basis for prioritization in the establishment of programs and the allocation of resources. This report describes the current regulatory environment of transitioning to risk-informed regulations with an emphasis on its background, concepts, regulatory guides, proposed options for modifying the 10CFR50, and risk-informed applications in U.S.A. Review of the risk informed applications utilizing the information provided by the PRAs and their insights in the U.S.NRC and nuclear industry will provide the insights of predicting the expected regulation changes in Korea. Also it could provide the applicable methods or guides for the implementation of the risk-informed applications in plant design and operations. (author)

  17. Risk informed decisions and regulations - STUK's policy and current practice

    International Nuclear Information System (INIS)

    Julin, A.; Niemalae, I.; Virolainen, R.

    2001-01-01

    Consideration of severe accidents beyond the traditional design basis, including full core melt accidents, has become an important ingredient of regulatory process in Finland. Accordingly, plant-specific level-1 and level-2 PSA studies are a regulatory requirement. These studies are being used in a living fashion both at the utilities and STUK. Plant specific living PSAs have been completed for all operating Finnish plants, including internal initiators, fires, flooding, harsh weather conditions seismic events for operation mode and internal events for low power mode. Many specific applications of the Living PSA have already been introduced but some are still waiting for further development such as Risk Informed ISI, IST and Tech Specs. Examples of safety issues, for which the PSA insights give an improved basis for decisions, are approvals of plant modifications and resolution of testing, inspection and maintenance strategies. PSA insights are also of value in assessing meaningfulness of requirements which are based on traditional engineering judgement but do not form an essential part of defence-in-depth concept. Examples of such requirements are details of safety classification and many Technical Specification requirements. STUK has recently conducted a pilot study on risk-informed ISI. The aim of the study was to explore how the plant specific PSAs could best be used for assessment of the ISI programmes. This paper discusses the findings obtained during the pilot study on risk-informed ISI of pipings. The study produced essential insights of the applied method. Furthermore, the study gave guidance to extract items for further development. Based on these results and overall experience the general suitability of the method for further application is evaluated. (author)

  18. Implementing risk-informed life-cycle design

    International Nuclear Information System (INIS)

    Hill, Ralph S.

    2009-01-01

    This paper describes a design process based on risk-informed probabilistic design methodologies that cover a facility's life-cycle from start of conceptual design through decontamination and decommissioning. The concept embodies use of probabilistic risk assessments to establish target reliabilities for facility systems and components. The target reliabilities are used for system based code margin exchange and performance simulation analyses to optimize design over all phases (design, construction, operation and decommissioning) of a facility's life-cycle. System based code margin exchange reduces excessive level of construction margins for passive components to appropriate levels resulting in a more flexible structure of codes and standards that improves facility reliability and cost. System and subsystem simulation analyses determine the optimum combination of initial system and component construction reliability, maintenance frequency, and inspection frequency for both active and passive components. The paper includes a description of these risk-informed life-cycle design processes, a summary of work being done, and a discussion of additional work needed to implement the process.

  19. Tridimensional ultrasonic images analysis for the in service inspection of fast breeder reactors; Analyse d'images tridimensionnelles ultrasonores pour l'inspection en service des reacteurs a neutrons rapides

    Energy Technology Data Exchange (ETDEWEB)

    Dancre, M

    1999-11-01

    Tridimensional image analysis provides a set of methods for the intelligent extraction of information in order to visualize, recognize or inspect objects in volumetric images. In this field of research, we are interested in algorithmic and methodological aspects to extract surface visual information embedded in volume ultrasonic images. The aim is to help a non-acoustician operator, possibly the system itself, to inspect surfaces of vessel and internals in Fast Breeder Reactors (FBR). Those surfaces are immersed in liquid metal, what justifies the ultrasonic technology choice. We expose firstly a state of the art on the visualization of volume ultrasonic images, the methods of noise analysis, the geometrical modelling for surface analysis and finally curves and surfaces matching. These four points are then inserted in a global analysis strategy that relies on an acoustical analysis (echoes recognition), an object analysis (object recognition and reconstruction) and a surface analysis (surface defects detection). Few literature can be found on ultrasonic echoes recognition through image analysis. We suggest an original method that can be generalized to all images with structured and non-structured noise. From a technical point of view, this methodology applied to echoes recognition turns out to be a cooperative approach between morphological mathematics and snakes (active contours). An entropy maximization technique is required for volumetric data binarization. (author)

  20. Automated ultrasonic inspection of nuclear plant components

    International Nuclear Information System (INIS)

    Baron, J.A.; Dolbey, M.P.

    1982-01-01

    For reasons of safety and efficiency, automated systems are used in performing ultrasonic inspection of nuclear components. An automated system designed specifically for the inspection of headers in a nuclear plant is described. In-service inspection results obtained with this system are shown to correlate with pre-service inspection results obtained by manual methods

  1. The application of the PSA important measures in risk-informed administrations

    International Nuclear Information System (INIS)

    Chen Yan; Fu Zhiwei; Jing Jianping; Zhang Chunming; Liu Hongquan

    2012-01-01

    The importance measures analyses of PSA are main approaches during the risk-informed administrations. This paper reviews kinds of importance measures, mainly researches the meaning of the FV and RAW importance measures, and introduces the applications of importance measures in the in-service testing and categorization of SSCs, finally, discusses the limitations of the importance measures analyses. (authors)

  2. Methodology for qualification of in-service inspection systems for WWER nuclear power plants. A publication of the extrabudgetary programme on the safety of WWER and RBMK nuclear power plants

    International Nuclear Information System (INIS)

    1998-03-01

    Program was initiated by IAEA in 1990 with the aim to assist the countries of Central and Eastern Europe and former Soviet Union in evaluating the safety of their first generation WWER-440/230 nuclear power plants. The main objectives were: to identify major design and operational safety issues; to establish international consensus on priorities for safety improvements; and to provide assistance in the review of the competence and and adequacy of safety improvement programs. The scope was extended in 1992 to include RBMK, WWER-440/312 and WWER-1000 plants in operation and under construction. Integrity of primary circuit is fundamental for the safe operation of any nuclear power plant. In-service inspection (ISI) in general terms and in particular, non-destructive tests (NDT) play a key role in maintaining primary circuit integrity. This report provides a methodology for qualification of ISI systems which might be used by WWER operating countries as a commonly accepted basis for further development of the necessary qualification related infrastructures. It also provides several qualification principles defining the administrative framework needed for the practical implementation of the methodology, a description of the process of qualification of an inspection system, specifying its minimum technical and documentation related requirements, as well as specific requirements with regard to the NDT procedures, equipment and personnel to be qualified and the test specimen to be used in practical trials. Finally, the report suggests an appropriate distribution of responsibilities among all the parties involved in a qualification process, based on international practice

  3. A risk informed safety classification for a Nordic NPP

    International Nuclear Information System (INIS)

    Jaenkaelae, K.

    2002-01-01

    The report describes a study to develop a safety classification proposal or classi- fication recommendations based on risks for selected equipment of a nuclear power plant. The application plant in this work is Loviisa NPP unit 1. The safety classification proposals are to be considered as an exercise in this pilot study and do not necessarily represent final proposals in a real situation. Comparisons to original safety classifications and technical specifications were made. The study concludes that it is possible to change safety classes or safety signifi- cances as considered in technical specifications and in in-service-inspections into both directions without endangering the safety or even by improving the safety. (au)

  4. Risk - Informed decision making at Loviisa NPP

    Energy Technology Data Exchange (ETDEWEB)

    Vaurio, J.K. [Fortum Power and Heat Oy, Loviisa (Finland)

    1999-09-01

    PSA has been used in many ways for risk-informed decision making at Loviisa power station. The most fruitful areas so far include: 1) Identification of dominating risk contributors and possible means for reducing risk by plant modification and improved procedures. 2) Providing risk perspective and economic criteria for assessing backfitting proposals. 3) Assessing the significance of ageing and needs for renewals. 4) Limiting, prioritising and optimising plant modifications. 5) Reducing testing requirements. 6) Justification of temporary aswell as permanent configurations and extended outage times. 7) Planning and prioritisation of training programs. (au)

  5. Risk - Informed decision making at Loviisa NPP

    International Nuclear Information System (INIS)

    Vaurio, J.K.

    1999-01-01

    PSA has been used in many ways for risk-informed decision making at Loviisa power station. The most fruitful areas so far include: 1) Identification of dominating risk contributors and possible means for reducing risk by plant modification and improved procedures. 2) Providing risk perspective and economic criteria for assessing backfitting proposals. 3) Assessing the significance of ageing and needs for renewals. 4) Limiting, prioritising and optimising plant modifications. 5) Reducing testing requirements. 6) Justification of temporary as well as permanent configurations and extended outage times. 7) Planning and prioritisation of training programs. (au)

  6. Moving along the risk-informed path - drivers and challenges

    International Nuclear Information System (INIS)

    Petrella, S.; Dermarkar, F.; Austman, D.; Chun, R.

    2004-01-01

    The use of risk criteria and information has always been an important component of the licensing of nuclear reactors in Ontario. Early applications included the development of Safety Design Matrices in the early 80's for more comprehensive design reviews, the use of the Darlington Probabilistic Safety Evaluation in the late-80's to support the C-6 event categorization process for the initial Darlington licensing, and the use of risk-insights, along with cost benefit criteria, to evaluate design options for the Pickering A special safety system design retrofits and modifications, such as Shutdown System (SDS) enhancement and Emergency Coolant Injection System (ECIS) upgrades. Operational uses have included the management of outage risk, the review of containment test frequencies, and the review of abnormal operating configurations such as maintenance of electrical power supplies. It is envisaged that such applications will continue, aided by the continued development of Probabilistic Risk Assessments techniques. To provide enhanced assurance of safety, to evaluate current and new safety-related issues as they arise, and to realize the full safety and economic benefits of risk-insights, OPG and Bruce Power have, along with their Industry partners, embarked on a path to further increase the use of risk-information in the operation and licensing of their reactors. Drivers include the resolution of long standing safety analysis issues surrounding LBLOCA analyses and generic action items, the application of risk-insights to guide the response to design, inspection, and analysis findings, and the optimization of operating, maintenance, and testing programs. As well, a major near term driver is input to plant refurbishment decisions. In moving to a more risk-informed approach to safety assessment, challenges include developing and implementing the required suite of concepts, tools, processes and criteria, and reconciling the current largely deterministic approach to safety

  7. Study on the risk-informed regulation of NPP

    International Nuclear Information System (INIS)

    Wang Chaogui

    2007-01-01

    The risk-informed regulation is a modern type of NPP safety management mode using both deterministic and probabilistic approaches. It is necessary to entirely and systematically study the associated regulations, standards and practices in order to promote the developments of risk-informed regulations in China. This paper introduces the risk-informed regulation, gives out the basic principles, method and acceptance risk criteria of risk-informed decision,making, discusses the PSA requirements for risk-informed decision-making and makes some suggestions about the application of risk-informed regulations in Chinese NPP. (authors)

  8. NASA Risk-Informed Decision Making Handbook

    Science.gov (United States)

    Dezfuli, Homayoon; Stamatelatos, Michael; Maggio, Gaspare; Everett, Christopher; Youngblood, Robert; Rutledge, Peter; Benjamin, Allan; Williams, Rodney; Smith, Curtis; Guarro, Sergio

    2010-01-01

    This handbook provides guidance for conducting risk-informed decision making in the context of NASA risk management (RM), with a focus on the types of direction-setting key decisions that are characteristic of the NASA program and project life cycles, and which produce derived requirements in accordance with existing systems engineering practices that flow down through the NASA organizational hierarchy. The guidance in this handbook is not meant to be prescriptive. Instead, it is meant to be general enough, and contain a sufficient diversity of examples, to enable the reader to adapt the methods as needed to the particular decision problems that he or she faces. The handbook highlights major issues to consider when making decisions in the presence of potentially significant uncertainty, so that the user is better able to recognize and avoid pitfalls that might otherwise be experienced.

  9. Inspection Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — FDA is disclosing the final inspection classification for inspections related to currently marketed FDA-regulated products. The disclosure of this information is not...

  10. RISK-INFORMED SAFETY MARGIN CHARACTERIZATION

    International Nuclear Information System (INIS)

    Dinh, Nam; Szilard, Ronaldo

    2009-01-01

    The concept of safety margins has served as a fundamental principle in the design and operation of commercial nuclear power plants (NPPs). Defined as the minimum distance between a system's 'loading' and its 'capacity', plant design and operation is predicated on ensuring an adequate safety margin for safety-significant parameters (e.g., fuel cladding temperature, containment pressure, etc.) is provided over the spectrum of anticipated plant operating, transient and accident conditions. To meet the anticipated challenges associated with extending the operational lifetimes of the current fleet of operating NPPs, the United States Department of Energy (USDOE), the Idaho National Laboratory (INL) and the Electric Power Research Institute (EPRI) have developed a collaboration to conduct coordinated research to identify and address the technological challenges and opportunities that likely would affect the safe and economic operation of the existing NPP fleet over the postulated long-term time horizons. In this paper we describe a framework for developing and implementing a Risk-Informed Safety Margin Characterization (RISMC) approach to evaluate and manage changes in plant safety margins over long time horizons

  11. Disclosing Risk Information: Assessing the Benefits

    International Nuclear Information System (INIS)

    Beierle, Thomas C.

    2003-01-01

    This paper describes a framework for examining the benefits of risk information disclosure and illustrates the framework through brief case studies of three information disclosure programs in the United States. I describe a general framework for analyzing the benefits of information disclosure and illustrate the framework by analyzing three disclosure programs in the United States: risk management planning (RMP), which provides detailed information on chemical accident risks and prevention; materials accounting, which provides information on how chemicals travel through processes at industrial facilities; and the Sector Facility Indexing Project (SFIP), which consolidates enforcement, compliance, and other data into a package of environmental performance indicators. This paper has outlined the types of benefits information disclosure programs ought to seek to achieve. Normative right-to-know benefits have been limited in some program because of intentionally circumscribed information sharing and apparent public disinterest. Substantive benefits have been more apparent, with many firms, agencies, NGOs, and others being able to point to the value of newly revealed information in better understanding environmental problems and the means to correct them. Instrumental benefits have been mixed, and firms appear to be responding to many motivations - not just public pressure - in deciding whether to improve environmental performance

  12. Forming homogeneous clusters for differential risk information

    International Nuclear Information System (INIS)

    Maardberg, B.

    1996-01-01

    Latent risk situations are always present in society. General information on these risk situations is supposed to be received differently by different groups of people in the population. In the aftermath of specific accidents different groups presumably have need of specific information about how to act to survive, to avoid injuries, to find more information, to obtain facts about the accidents etc. As targets for information these different groups could be defined in different ways. The conventional way is to divide the population according to demographic variables, such as age, sex, occupation etc. Another way would be to structure the population according to dependent variables measured in different studies. They may concern risk perception, emotional reactions, specific technical knowledge of the accidents, and belief in the information sources. One procedure for forming such groupings of people into homogeneous clusters would be by statistical clustering methods on dependent variables. Examples of such clustering procedures are presented and discussed. Data are from a Norwegian study on the perception of radiation from nuclear accidents and other radiation sources. Speculations are made on different risk information strategies. Elements of a research programme are proposed. (author)

  13. Inspection planning

    International Nuclear Information System (INIS)

    Korosec, D.; Levstek, M.F.

    2001-01-01

    Slovenian Nuclear Safety Administration (SNSA) division of nuclear and radiological safety inspection has developed systematic approach to their inspections. To be efficient in their efforts regarding regular and other types of inspections, in past years, the inspection plan has been developed. It is yearly based and organized on a such systematic way, that all areas of nuclear safety important activities of the licensee are covered. The inspection plan assures appropriate preparation for conducting the inspections, allows the overview of the progress regarding the areas to be covered during the year. Depending on the licensee activities and nature of facility (nuclear power plant, research reactor, radioactive waste storage, others), the plan has different levels of intensity of inspections and also their frequency. One of the basic approaches of the plan is to cover all nuclear and radiological important activities on such way, that all regulatory requests are fulfilled. In addition, the inspection plan is a good tool to improve inspection effectiveness based on previous experience and allows to have the oversight of the current status of fulfillment of planned inspections. Future improvement of the plan is necessary in the light of newest achievements on this field in the nuclear world, that means, new types of inspections are planned and will be incorporated into plan in next year.(author)

  14. In-service inspection of electrical items

    International Nuclear Information System (INIS)

    Sastry, M.S.N.

    2002-01-01

    Power Supply and Distribution System caters to electrical power requirements of all drives and other equipment. The system also provides control power. Main equipment in the system are Transformers, Switch gear, cables, motors, emergency D- G sets, UPS, and storage battery banks. The talk is covered under the following broad heads: 1. Brief description of typical power supply system, 2. Insulation checks in LV, MV, and HV systems, 3. Monitoring the insulating oil of transformer, 4. Eddy current checking of the motor cores, 5. Checking of cable and bus bar joints, 6. Periodic check on batteries

  15. In service inspection for steam generator tubes

    International Nuclear Information System (INIS)

    Comby, R.; Eyrolles, Ph.

    1988-01-01

    In this paper the authors show the means putting in place for examination of steam generators tubes. These means (eddy current probes, ultrasonic testing) associated with a knowledge on degradation phenomena allow mapping controlled tubes and limiting undesirable obturations [fr

  16. A need for in service inspection reliability

    International Nuclear Information System (INIS)

    Pons, F.; Samman, J.

    1988-01-01

    Electricite de France, the French electrical utility, has developed both lab and field testing means for non destructive testing equipment as part of its overall quality assurance program. These testing means are presented by the authors, The quality assurance program is discussed

  17. New approach for risk based inspection of H2S based Process Plants

    International Nuclear Information System (INIS)

    Vinod, Gopika; Sharma, Pavan K.; Santosh, T.V.; Hari Prasad, M.; Vaze, K.K.

    2014-01-01

    Highlights: • Study looks into improving the consequence evaluation in risk based inspection. • Ways to revise the quantity factors used in qualitative approach. • New approach based on computational fluid dynamics along with probit mathematics. • Demonstrated this methodology along with a suitable case study for the said issue. - Abstract: Recent trend in risk informed and risk based approaches in life management issues have certainly put the focus on developing estimation methods for real risk. Idea of employing risk as an optimising measure for in-service inspection, termed as risk based inspection, was accepted in principle from late 80s. While applying risk based inspection, consequence of failure from each component needs to be assessed. Consequence evaluation in a Process Plant is a crucial task. It may be noted that, in general, the number of components to be considered for life management is very large and hence the consequence evaluation resulting from their failures (individually) is a laborious task. Screening of critical components is usually carried out using simplified qualitative approach, which primarily uses influence factors for categorisation. This necessitates logical formulation of influence factors and their ranges with a suitable technical basis for acceptance from regulators. This paper describes application of risk based inspection for H 2 S based Process Plant along with the approach devised for handling the influence factor related to the quantity of H 2 S released

  18. Risk-informed ranking of engineering projects

    International Nuclear Information System (INIS)

    Jyrkama, M.; Pandey, M.

    2011-01-01

    Refurbishment planning requires prudent investment decisions with respect to the various systems and components at the station. These decisions are influenced by many factors, including engineering, safety, regulatory, economic, and political constraints. From an engineering perspective, the concept of cost-benefit analysis is a common way to allocate capital among various projects. Naturally, the 'best' or optimal project should have the lowest cost and the highest benefit. In the context of risk-informed decision making (RIDM), a process that has been widely embraced by the global nuclear community, the costs and benefits must further be 'weighted' by probabilities to estimate the underlying risk associated with the various planning alternatives. The main purpose of this study is to illustrate how risk and reliability information can be integrated into the refurbishment planning process to facilitate more objective and transparent investment decisions. The methodology is based on the concept of generation risk assessment (GRA) which provides a systematic approach for balancing investment costs with the reduction in overall financial risk. In addition to reliability predictions, the model provides estimates for the level of risk reduction associated with each system/project and also the break-even point for investment. This information is vital for project ranking, and helps to address the key question of whether capital investment should be made in the most risk critical systems, or in systems that reduce the overall risk the most. The application of the proposed methodology requires only basic information regarding the current reliability of each engineering system, which should be readily available from plant records and routine condition assessments. Because the methodology can be readily implemented in a Microsoft Excel spreadsheet, all plausible (e.g., bounding) planning scenarios, with or without investment, can also be generated quickly and easily, while

  19. Probabilistic safety analysis and risk-based inspection of nuclear research reactors: state-of-the-art and implementation proposal

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Raíssa O.; Vasceoncelos, Vanderley de; Soares, Wellington A.; Silva Júnior, Silvério F.; Raso, Amanda L.; Mesquita, Amir Z., E-mail: raissaomarques@gmail.com, E-mail: vasconv@cdtn.br, E-mail: soaresw@cdtn.br, E-mail: silvasf@cdtn.br, E-mail: amandaraso@hotmail.com, E-mail: amir@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Industrial facilities systems deteriorate over time during operation, thus increasing the possibility of accidents. Risk-Based Inspection (RBI) classifies such systems by their risk information with the purpose of prioritizing inspection efforts. RBI can reduce inspection activities, resulting in lower risk levels, and maintaining reliability and safety in acceptable levels. Risk-Informed In-Service Inspection (RI-ISI) is a RBI approach used in nuclear industry. RI-ISI uses outcomes from Probabilistic Safety Analysis (PSA) of Nuclear Power Plants (NPP) to plan In-Service Inspections (ISI). Despite nuclear research reactors are simpler and have lower risks than power reactors, the application of PSA to them may be useful for safety improvements once they are more flexible, provide easier access to its core, and allow changes in fuel configurations in case of experimental tests. Ageing management of structures, systems and components important to safety of a nuclear research reactor throughout its lifetime is also required to assure continued adequacy of safety levels, reliable operation, and compliance with operational limits and conditions. This includes periodic review of ISI programs in which monitoring of material deterioration and aging effects are considered, and that can be supported by the RBI approach. A review of state-of-the-art of PSA and RBI applications to nuclear reactors is presented in this work. Advantages to apply these methodologies are also analyzed. PSA and RBI implementation proposal applied to nuclear research reactors is also presented, as well as its application to a TRIGA research nuclear reactor using computer codes developed by ReliaSoft® Corporation. (author)

  20. Probabilistic safety analysis and risk-based inspection of nuclear research reactors: state-of-the-art and implementation proposal

    International Nuclear Information System (INIS)

    Marques, Raíssa O.; Vasceoncelos, Vanderley de; Soares, Wellington A.; Silva Júnior, Silvério F.; Raso, Amanda L.; Mesquita, Amir Z.

    2017-01-01

    Industrial facilities systems deteriorate over time during operation, thus increasing the possibility of accidents. Risk-Based Inspection (RBI) classifies such systems by their risk information with the purpose of prioritizing inspection efforts. RBI can reduce inspection activities, resulting in lower risk levels, and maintaining reliability and safety in acceptable levels. Risk-Informed In-Service Inspection (RI-ISI) is a RBI approach used in nuclear industry. RI-ISI uses outcomes from Probabilistic Safety Analysis (PSA) of Nuclear Power Plants (NPP) to plan In-Service Inspections (ISI). Despite nuclear research reactors are simpler and have lower risks than power reactors, the application of PSA to them may be useful for safety improvements once they are more flexible, provide easier access to its core, and allow changes in fuel configurations in case of experimental tests. Ageing management of structures, systems and components important to safety of a nuclear research reactor throughout its lifetime is also required to assure continued adequacy of safety levels, reliable operation, and compliance with operational limits and conditions. This includes periodic review of ISI programs in which monitoring of material deterioration and aging effects are considered, and that can be supported by the RBI approach. A review of state-of-the-art of PSA and RBI applications to nuclear reactors is presented in this work. Advantages to apply these methodologies are also analyzed. PSA and RBI implementation proposal applied to nuclear research reactors is also presented, as well as its application to a TRIGA research nuclear reactor using computer codes developed by ReliaSoft® Corporation. (author)

  1. Probabilistic Fatigue Life Updating for Railway Bridges Based on Local Inspection and Repair.

    Science.gov (United States)

    Lee, Young-Joo; Kim, Robin E; Suh, Wonho; Park, Kiwon

    2017-04-24

    Railway bridges are exposed to repeated train loads, which may cause fatigue failure. As critical links in a transportation network, railway bridges are expected to survive for a target period of time, but sometimes they fail earlier than expected. To guarantee the target bridge life, bridge maintenance activities such as local inspection and repair should be undertaken properly. However, this is a challenging task because there are various sources of uncertainty associated with aging bridges, train loads, environmental conditions, and maintenance work. Therefore, to perform optimal risk-based maintenance of railway bridges, it is essential to estimate the probabilistic fatigue life of a railway bridge and update the life information based on the results of local inspections and repair. Recently, a system reliability approach was proposed to evaluate the fatigue failure risk of structural systems and update the prior risk information in various inspection scenarios. However, this approach can handle only a constant-amplitude load and has limitations in considering a cyclic load with varying amplitude levels, which is the major loading pattern generated by train traffic. In addition, it is not feasible to update the prior risk information after bridges are repaired. In this research, the system reliability approach is further developed so that it can handle a varying-amplitude load and update the system-level risk of fatigue failure for railway bridges after inspection and repair. The proposed method is applied to a numerical example of an in-service railway bridge, and the effects of inspection and repair on the probabilistic fatigue life are discussed.

  2. Current activities and challenges of the European network for inspection and qualification (ENIQ)

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Oliver [European Commission, Joint Research Centre (JRC), Petten (Netherlands). Institute for Energy and Transport (IET); Martin, Etienne [EDF, St Denis (France). Direction Production Ingenierie; Booler, Russ [AMEC Clean Energy Europe, Warrington (United Kingdom); Zetterwall, Tommy [Swedish Qualification Centre, Taeby (Sweden); Walker, Tony [Rolls-Royce Submarines, Derby (United Kingdom)

    2014-10-15

    This article describes the development of the European Network for Inspection and Qualification (ENIQ) since the previous presentation of the network in the 2011 April/May edition of this journal, covering mainly the new technical challenges facing the network and resulting projects as well as the establishment of the new Task Group for Inspection Qualification Bodies. ENIQ is a utility-driven network dealing with the reliability and effectiveness of non-destructive testing (NDT) for nuclear power plants (NPP). ENIQ is recognised as one of the main contributors to today's global qualification codes and guidelines for in-service inspection (ISI) and has published nearly 50 documents. Among them are the 'European Methodology for Qualification of Non-Destructive Testing', the first qualification methodology based on technical justifications, the 'European Framework Document for Risk-Informed In-Service Inspection (RI-ISI)', and various recommend practices. In addition ENIQ has carried out two pilot studies and a number of surveys. In 2012, ENIQ joined the European based R and D association on Gen II and III reactors, NUGENIA, making ENIQ its 8{sup th} technical area. Following the entry into NUGENIA, ENIQ members have updated the ENIQ roadmap and included a number of new technical challenges facing its members in the near future. Also ENIQ established a third task group in 2013, the Task Group for Inspection Qualification Bodies (TGIQB), which should serve as an exchange forum for inspection qualification bodies. ENIQ is currently preparing or performing new projects and studies to tackle these challenges and new recommended practices and reports are likely to evolve from these projects, which will enable ENIQ to maintain its role as one of the main contributors to today's global qualification codes and guidelines for ISI.

  3. Current activities and challenges of the European network for inspection and qualification (ENIQ)

    International Nuclear Information System (INIS)

    Martin, Oliver; Martin, Etienne; Zetterwall, Tommy; Walker, Tony

    2014-01-01

    This article describes the development of the European Network for Inspection and Qualification (ENIQ) since the previous presentation of the network in the 2011 April/May edition of this journal, covering mainly the new technical challenges facing the network and resulting projects as well as the establishment of the new Task Group for Inspection Qualification Bodies. ENIQ is a utility-driven network dealing with the reliability and effectiveness of non-destructive testing (NDT) for nuclear power plants (NPP). ENIQ is recognised as one of the main contributors to today's global qualification codes and guidelines for in-service inspection (ISI) and has published nearly 50 documents. Among them are the 'European Methodology for Qualification of Non-Destructive Testing', the first qualification methodology based on technical justifications, the 'European Framework Document for Risk-Informed In-Service Inspection (RI-ISI)', and various recommend practices. In addition ENIQ has carried out two pilot studies and a number of surveys. In 2012, ENIQ joined the European based R and D association on Gen II and III reactors, NUGENIA, making ENIQ its 8 th technical area. Following the entry into NUGENIA, ENIQ members have updated the ENIQ roadmap and included a number of new technical challenges facing its members in the near future. Also ENIQ established a third task group in 2013, the Task Group for Inspection Qualification Bodies (TGIQB), which should serve as an exchange forum for inspection qualification bodies. ENIQ is currently preparing or performing new projects and studies to tackle these challenges and new recommended practices and reports are likely to evolve from these projects, which will enable ENIQ to maintain its role as one of the main contributors to today's global qualification codes and guidelines for ISI.

  4. Inspection vehicle

    International Nuclear Information System (INIS)

    Takahashi, Masaki; Omote, Tatsuyuki; Yoneya, Yutaka; Tanaka, Keiji; Waki, Tetsuro; Yoshida, Tomiji; Kido, Tsuyoshi.

    1993-01-01

    An inspection vehicle comprises a small-sized battery directly connected with a power motor or a direct power source from trolly lines and a switching circuit operated by external signals. The switch judges advance or retreat by two kinds of signals and the inspection vehicle is recovered by self-running. In order to recover the abnormally stopped inspection vehicle to the targeted place, the inspection vehicle is made in a free-running state by using a clutch mechanism and is pushed by an other vehicle. (T.M.)

  5. Importance measures in risk-informed decision making: Ranking, optimisation and configuration control

    Energy Technology Data Exchange (ETDEWEB)

    Vaurio, Jussi K., E-mail: jussi.vaurio@pp1.inet.fi [Prometh Solutions, Hiihtaejaenkuja 3K, 06100 Porvoo (Finland)

    2011-11-15

    This paper describes roles, extensions and applications of importance measures of components and configurations for making risk-informed decisions relevant to system operations, maintenance and safety. Basic importance measures and their relationships are described for independent and mutually exclusive events and for groups of events associated with common cause failures. The roles of importances are described mainly in two groups of activities: (a) ranking safety significance of systems, structures, components and human actions for preventive safety assurance activities, and (b) making decisions about permissible permanent and temporary configurations and allowed configuration times for regulation, technical specifications and for on-line risk monitoring. Criticality importance and sums of criticalities turn out to be appropriate measures for ranking and optimization. Several advantages are pointed out and consistent ranking of pipe segments for in-service inspection is provided as an example. Risk increase factor and its generalization risk gain are most appropriately used to assess corrective priorities and acceptability of a situation when components are already failed or when planning to take one or more components out of service for maintenance. Precise definitions are introduced for multi-failure configurations and it is shown how they can be assessed under uncertainties, in particular when common cause failures or success states may be involved. A general weighted average method is compared to other candidate methods in benchmark cases. It is the preferable method for prediction when a momentary configuration is known or only partially known. Potential applications and optimization of allowed outage times are described. The results show how to generalize and apply various importance measures to ranking and optimization and how to manage configurations in uncertain multi-failure situations. - Highlights: > Rigorous methods developed for using importances

  6. Importance measures in risk-informed decision making: Ranking, optimisation and configuration control

    International Nuclear Information System (INIS)

    Vaurio, Jussi K.

    2011-01-01

    This paper describes roles, extensions and applications of importance measures of components and configurations for making risk-informed decisions relevant to system operations, maintenance and safety. Basic importance measures and their relationships are described for independent and mutually exclusive events and for groups of events associated with common cause failures. The roles of importances are described mainly in two groups of activities: (a) ranking safety significance of systems, structures, components and human actions for preventive safety assurance activities, and (b) making decisions about permissible permanent and temporary configurations and allowed configuration times for regulation, technical specifications and for on-line risk monitoring. Criticality importance and sums of criticalities turn out to be appropriate measures for ranking and optimization. Several advantages are pointed out and consistent ranking of pipe segments for in-service inspection is provided as an example. Risk increase factor and its generalization risk gain are most appropriately used to assess corrective priorities and acceptability of a situation when components are already failed or when planning to take one or more components out of service for maintenance. Precise definitions are introduced for multi-failure configurations and it is shown how they can be assessed under uncertainties, in particular when common cause failures or success states may be involved. A general weighted average method is compared to other candidate methods in benchmark cases. It is the preferable method for prediction when a momentary configuration is known or only partially known. Potential applications and optimization of allowed outage times are described. The results show how to generalize and apply various importance measures to ranking and optimization and how to manage configurations in uncertain multi-failure situations. - Highlights: → Rigorous methods developed for using importances

  7. Discussion about risk-informed regulations on the nuclear safety

    International Nuclear Information System (INIS)

    Gu Yeyi

    2008-01-01

    The article introduces the background and status quo of regulations on the nuclear safety in China, and points out the inadequacies existing with the current regulations. The author explains the risk-informed safety management concerning its development, status quo, and achievements made, in an attempt to make out the trend of improving regulations on the nuclear safety through risk-informed methods. Combining the U.S. development program of establishing risk-informed regulations on the nuclear safety, the author narrates principles and features of the new regulations system, and provides suggestions for the promotion of risk-informed safety management and establishment of risk-informed regulations on the nuclear safety. (author)

  8. Ultrasonic inspection

    International Nuclear Information System (INIS)

    Satittada, Gannaga

    1984-01-01

    Ultrasonic inspection is one of the most widely used methods for nondestructive inspection. The beam of high-frequency sound wave, ultrasonic wave, is introduced into the material. It travels through the material with some attendant loss of energy and can be reflected at interfaces. The reflected beam is detected and analyzed. Ultrasonic inspection is used to detect flaws in metal parts as well as in welded, brazed and bonded joints during research work and developing production and service. It is also used to detect and locate porosity, pipe, and flakes. In addition, it can be used for the measurement of metal thickness. Ultrasonic inspection is therefore used for quality control and material inspection in all major industries

  9. Current products and future plan of regulatory technology R and D for risk-informed regulation and applications

    International Nuclear Information System (INIS)

    Song, K. Y.; Lee, C. J.; Kim, W. S.; Jeong, D. W.; Kim, H. J.

    2002-01-01

    The first phase of a R and D project for risk-informed regulation (RIR) and applications (RIA) has been finished. Various results which would be useful for preparing domestic RIR system were accomplished, in areas of safety goals and general principles of RIR, which provide fundamental bases for establishment of RIR system as well as regulatory review guides, which ensure the quality for PSA. RIA guidelines for ISI, IST, MOV, Tech.-Sepc. also have been developed, implementing some pilot plant applications. As essential documents for actual RIR inspection, risk-informed inspection guides and implementation guide for maintenance effectiveness were prepared. In the second phase of R and D, two projects on RIR area will be performed. One is to study on institutionalization of RIR and performance-based regulation, another is to develop a PSA model for regulatory audit as well as regulatory technology for risk monitoring

  10. Hospital Inspections

    Data.gov (United States)

    U.S. Department of Health & Human Services — Welcome to hospitalinspections.org, a website run by the Association of Health Care Journalists (AHCJ) that aims to make federal hospital inspection reports easier...

  11. Boiler inspection manipulator for Torness Power Station

    International Nuclear Information System (INIS)

    Carrey, R.T.A.; Yule, I.Y.; Sibson, S.; Playle, M.J.

    1996-01-01

    The Advanced Gas-cooled Reactors at Torness and Heysham 2 are provided with dedicated access for remote inspection equipment. These in-service inspection (ISI) accesses comprise 12 penetrations above the core for inspection of the above core area and boilers, 12 below core penetrations for inspection of the lower boiler area and access through any of the 8 gas circulator penetrations for inspection of the sub-diagrid area. This paper describes a manipulator which will access the reactor from above the core via any of the 8 peripheral penetrations. (UK)

  12. Outlook for risk assessment and risk-informed regulations

    International Nuclear Information System (INIS)

    Chakraborty, S.; Breutel, C.; Khatib-Rahbar, M.

    2000-01-01

    The Western nuclear regulatory process has evolved from the initial engineering judgment' framework of the 1960's, the prescriptive deterministic requirements of the 1970s, the transition years of the 1980s, to the present day movement toward risk-informed approaches. In this paper, a short overview of the historic development of safety regulation is provided. The critique of traditional regulatory practice will be summarized and the features of risk-informed regulation will be discussed. The implementation of risk-informed regulation is considered on the basis of general legal principles common to many member states of the NEA and IAEA. In a process to risk-inform regulation, principles such as equal treatment, proportionality of rules and predictability of administrative action are found to be important. (author)

  13. Nuclear Plant Modification in a Risk-Informed Environment

    International Nuclear Information System (INIS)

    Gallucci, Raymond H.V.

    2002-01-01

    This paper examines a specific nuclear power plant modification performed in a risk-informed regulatory environment. It quantifies both the permanent and temporary effects of the modification, and performs a cost-benefit evaluation. (authors)

  14. Link Between RI-ISI and Inspection Qualification: Relationship between Defect Detection Rate and Margin of Detection

    International Nuclear Information System (INIS)

    Shepherd, Barrie; Goujon, Sophie; Whittle, John

    2007-01-01

    Quantitative risk-informed in-service inspection (RI-ISI) requires a quantitative measurement of inspection effectiveness if the risk change associated with an inspection is to be determined. Knowing the probability of detection (POD) as a function of defect depth (through wall dimension) would provide ideal information. However the main in-service inspection method for nuclear plant is ultrasonics, for which defect detection capability depends on a wide variety of parameters besides defect depth, such as defect orientation, roughness, location, shape etc. In recognition of this the European approach to inspection qualification is generally based on some combination of technical justification, and practical trials on a relatively limited number of defects. This inspection qualification process involves demonstrating that defects of concern will generate responses in excess of the specified recording level or noise, depending on the inspection. It is not currently designed to quantify the probability with which defects will be detected. The work described in this report has been performed in order to help address the problem of how the information generated during inspection qualification can be used as an input for RI-ISI. The approach adopted has been to recognise that as the defect response increases above the recording or noise level, the probability of detecting defects is likely to increase. The work therefore involved an investigation of the relationship between POD (strictly speaking defect detection rate) and margin of detection. It involved blind manual and automated ultrasonic trials on artificial defects in test plates designed to generate a range of signal responses. The detection rate for defects which provided signals at a particular level above noise or above a recording level was then measured. A relationship between defect detection rate and margin of detection has been established based on these trials. In addition to establishing a stronger link

  15. Structuring a risk-informed and performance-based process for optimization of regulation for Laguna Verde NPP

    International Nuclear Information System (INIS)

    Rodriguez-Hernandez, A.

    2001-01-01

    This work describes the plan for a process to incorporate into the regulatory activities the risk information derived from probabilistic risk assessments, as well as information generated by the periodic evaluation of the Maintenance Rule (MR, 10CFR50.65). The current status of the Laguna Verde NPP (LVNPP) risk analysis, PSA Level 1, allows determining in a reliable way the accident scenarios and the involved systems having significant impact on safety. The determination of system's risk significance allows carrying out a prioritization of safety issues to be evaluated and inspected; for example, operational events, changes to technical specifications, design modifications, inspection priorities, etc. In addition, complementary and basic information are the results generated by the performance monitoring of structures, systems and components (SSCs) under the scope of the MR. The SSCs performance trends are indicatives to focus evaluation and inspection activities on important issues. Then, with the reportability in short periods the performance evaluations of SSCs and the incorporation of a process of risk management, the evaluation and inspection activities will be directed to those risk significant systems showing degraded performance. Therefore, based on systems performance results and risk information, it is feasible to have certain flexibility or a better balance between the regulatory requirements. Inside this process, a consensus is needed with the utility to establish quality attributes for the plant-specific PSA, as well as the rules to be followed in the use of this tool and the kind of information to be reported for MR results. (author)

  16. A web environment for inspection service

    International Nuclear Information System (INIS)

    Robles Guemes, N.; Garcia Heras, M.; Cueto-Felgueroso Garcia, C.; Pelaez Gutierrez, J. A.

    2013-01-01

    The in-service inspection fundamental objective is to maintain the structural integrity of structures, systems and components during the life in the installation service. Nuclear power plants are required to implement a Service inspection program in accordance with the established regulation by the Regulatory body.

  17. Operational inspections

    International Nuclear Information System (INIS)

    Bystersky, M.

    1997-01-01

    Special equipment is described, designed for inspection of reactor pressure vessels performed from the inside. Central shaft manipulator ZMM-5 is available for crack detection control using ultrasound and eddy currents, for visual check of surfaces, repair works at the reactor pressure vessel, and hardness measurements. The manipulator consists of the manipulator bridge, a cable container, shaft segments, a control mechanism and auxiliary parts. Eight inspections were performed at the Bohunice nuclear power plant and two at the Paks nuclear power plant. (M.D.)

  18. Use of risk information to safety regulation. Reprocessing facilities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    A procedure of probabilistic risk assessment (PRA) for a reprocessing facility has been under the development aiming to utilize risk information for safety regulations in this project. Activities in the fiscal year 2012 are summarized in the paper. A major activity is a fundamental study on a concept of serious accidents, requirements of serious accident management, and a policy of utilizing risk information for fabrication and reprocessing facilities. Other than the activity a study on release and transport of aerial radioactive materials at a serious accident in a reprocessing facility has been conducted. The outline and results are provided in the chapter 1 and 2 respectively. (author)

  19. Use of risk information to safety regulation. Fabrication facilities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    A procedure of ISA (Integrated Safety Analysis) for uranium fuel fabrication/enrichment facilities has been under the development aiming to utilize risk information for safety regulations in this project. Activities in the fiscal year 2012 are summarized in the paper. There are two major activities in the year. First one is a study on ISA procedure for external events such as earthquakes. Second one is that for chemical consequences such as UF6 and HF. Other than the activities a fundamental study on a policy of utilizing risk information was conducted. The outline and results are provided in the chapter 1 and 2 respectively. (author)

  20. Regulatory use of risk information - initial developments at Slovenian Nuclear Safety Administration

    International Nuclear Information System (INIS)

    Muehleisen, A.; Koncar, M.; Vojnovic, D.; Persic, A.

    2004-01-01

    Similarly to other regulators worldwide, the SNSA intends to enhance the use of PSA and risk insights in its activities in order to ensure a better and more focused regulatory oversight as well as improved interface with a licensee. The main aim of the SNSA is to establish PSA as a standard tool to complement the deterministic based regulation for a variety of regulatory tasks. The PSA applications should, in particular, support the decision making process as well as the interactions with the Krsko NPP. As a first step in the internal use of PSA, PSA event analysis and risk based performance indicators are being introduced. In 2004, the SNSA will start introducing risk follow up and risk informed inspections. By mid 2005 the legal basis for the use of PSA will be also established in Slovenian legislation. (author)

  1. 47 CFR 80.953 - Inspection and certification.

    Science.gov (United States)

    2010-10-01

    ... date on which it is placed in service. (b) An inspection and certification of a ship subject to the... must be recorded in the ship's radiotelephone log and include: (1) The date the inspection was... part and has successfully passed the inspection. (c) The vessel owner, operator, or ship's master must...

  2. 46 CFR 61.05-10 - Boilers in service.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Boilers in service. 61.05-10 Section 61.05-10 Shipping... INSPECTIONS Tests and Inspections of Boilers § 61.05-10 Boilers in service. (a) Each boiler, including superheater, reheater, economizer, auxiliary boiler, low-pressure heating boiler, and unfired steam boiler...

  3. Supporting risk-informed decisions during business process execution

    NARCIS (Netherlands)

    Conforti, R.; Leoni, de M.; La Rosa, M.; Aalst, van der W.M.P.; Salinesi, C.; Norrie, M.C.; Pastor, O.

    2013-01-01

    This paper proposes a technique that supports process participants in making risk-informed decisions, with the aim to reduce the process risks. Risk reduction involves decreasing the likelihood and severity of a process fault from occurring. Given a process exposed to risks, e.g. a financial process

  4. Risk-informed approach in US-APWR technical specifications

    International Nuclear Information System (INIS)

    Saji, Etsuro; Tanaka, Futoshi; Kuroiwa, Katsuya; Kawai, Katsunori

    2009-01-01

    The Risk-Managed Technical Specifications and the Surveillance Frequency Control Program have been adopted in the US-APWR Technical Specifications. These risk-informed approaches are unique among the technical specifications for the advanced light water reactor designs adopted by planned nuclear power stations in the United States. (author)

  5. Risk Informed Design as Part of the Systems Engineering Process

    Science.gov (United States)

    Deckert, George

    2010-01-01

    This slide presentation reviews the importance of Risk Informed Design (RID) as an important feature of the systems engineering process. RID is based on the principle that risk is a design commodity such as mass, volume, cost or power. It also reviews Probabilistic Risk Assessment (PRA) as it is used in the product life cycle in the development of NASA's Constellation Program.

  6. Studies on the effect of flaw detection probability assumptions on risk reduction at inspection

    Energy Technology Data Exchange (ETDEWEB)

    Simola, K.; Cronvall, O.; Maennistoe, I. (VTT Technical Research Centre of Finland (Finland)); Gunnars, J.; Alverlind, L.; Dillstroem, P. (Inspecta Technology, Stockholm (Sweden)); Gandossi, L. (European Commission Joint Research Centre, Brussels (Belgium))

    2009-12-15

    The aim of the project was to study the effect of POD assumptions on failure probability using structural reliability models. The main interest was to investigate whether it is justifiable to use a simplified POD curve e.g. in risk-informed in-service inspection (RI-ISI) studies. The results of the study indicate that the use of a simplified POD curve could be justifiable in RI-ISI applications. Another aim was to compare various structural reliability calculation approaches for a set of cases. Through benchmarking one can identify differences and similarities between modelling approaches, and provide added confidence on models and identify development needs. Comparing the leakage probabilities calculated by different approaches at the end of plant lifetime (60 years) shows that the results are very similar when inspections are not accounted for. However, when inspections are taken into account the predicted order of magnitude differs. Further studies would be needed to investigate the reasons for the differences. Development needs and plans for the benchmarked structural reliability models are discussed. (author)

  7. Studies on the effect of flaw detection probability assumptions on risk reduction at inspection

    International Nuclear Information System (INIS)

    Simola, K.; Cronvall, O.; Maennistoe, I.; Gunnars, J.; Alverlind, L.; Dillstroem, P.; Gandossi, L.

    2009-12-01

    The aim of the project was to study the effect of POD assumptions on failure probability using structural reliability models. The main interest was to investigate whether it is justifiable to use a simplified POD curve e.g. in risk-informed in-service inspection (RI-ISI) studies. The results of the study indicate that the use of a simplified POD curve could be justifiable in RI-ISI applications. Another aim was to compare various structural reliability calculation approaches for a set of cases. Through benchmarking one can identify differences and similarities between modelling approaches, and provide added confidence on models and identify development needs. Comparing the leakage probabilities calculated by different approaches at the end of plant lifetime (60 years) shows that the results are very similar when inspections are not accounted for. However, when inspections are taken into account the predicted order of magnitude differs. Further studies would be needed to investigate the reasons for the differences. Development needs and plans for the benchmarked structural reliability models are discussed. (author)

  8. Efficient improvement of nuclear power plant safety by reorganization of risk-informed safety importance evaluation methods for piping welded portions

    Energy Technology Data Exchange (ETDEWEB)

    Irie, Takashi; Hanafusa, Hidemitsu; Suyama, Takeshi [Institute of Nuclear Safety System, Inc., Mihama, Fukui (Japan); Morota, Hidetsugu; Kojima, Sigeo; Mizuno, Yoshinobu [Computer Software Development Co., Ltd., Tokyo (Japan)

    2002-09-01

    In this work, risk information was used to evaluate the safety importance of piping welded portions which were important for plant operation and maintenance of nuclear power plants. There are two types of risk-informed safety importance evaluation methods, namely the ASME method and the EPRI method. Since both methods have advantages and disadvantages, elements of each method were combined and reorganized. Considerations included whether the degradation mechanisms would be objectively evaluated and whether plant safety would be efficiently improved. The most objective and efficient method was as follows. Piping failure potential is quantitatively and objectively evaluated for failure with probabilistic fracture mechanics (PFM) and for other degradation mechanisms with empirical failure rates, and conditional core damage probability (CCDP) is calculated with PSA. This method reduces the inspected segment numbers to 1/4 of the deterministic method and increases the ratio of risk, which is covered by the inspected segments, to total risk from 80% of the deterministic method to 95%. Piping inspection numbers decreased for safety injection systems that were required the inspections by the deterministic method. Piping inspections were required for part of main feed water and main steam systems that were not required the inspections by the deterministic method. (author)

  9. Ultrasonic inspection of inpile tubes

    International Nuclear Information System (INIS)

    Boyd, D.M.; Bossi, H.

    1985-01-01

    The in-service inspection (ISI) of inpile tubes can be performed accurately and safely with a semiautomatic ultrasonic inspection system. The ultrasonic technique uses a set of multiple transducers to detect and size cracks, voids, and laminations radially and circumferentially. Welds are also inspected for defects. The system is designed to inspect stainless steel and Inconel tubes ranging from 53.8 mm (2.12 in.) to 101.6 mm (4 in.) inner diameter with wall thickness on the order of 5 mm. The inspection head contains seven transducers mounted in a surface-following device. Six angle-beam transducers generate shear waves in the tubes. Two of the six are oriented to detect circumferential cracks, and two detect axial cracks. Although each of these four transducers is used in the pulse-echo mode, they are oriented in aligned sets so pitch-catch operation is possible if desired. The remaining angle-beam transducers are angulated to detect flaws that are off axial or circumferential orientation. The seventh transducer is used for longitudinal inspection and detects and sizes laminar-type defects

  10. Proceedings of the IAEA Specialists' Meeting on experience and further improvement of in-service inspection methods and programmes of NPPs with particular emphasis on on-line techniques

    International Nuclear Information System (INIS)

    1989-01-01

    The proceedings are presented of an IAEA specialists meeting devoted to the exchange of views and experience with respect to understanding and quantifying materials ageing and degradation processes, to assessing residual life of components, to in-service materials testing, all this with the objective of improving reliability and, wherever possible, extending the useful life of nuclear power plants. (L.O.)

  11. Proposed rulemaking to risk-inform special treatment requirements

    International Nuclear Information System (INIS)

    Reed, Timothy A.; McKenna, Eileen M.

    2003-01-01

    This paper presents the status of Nuclear Regulatory Commission (NRC) rulemaking efforts to risk-inform special treatment requirements that reside in Title 10 of the Code of Federal Regulations, 10 CFR Part 21, Part 50, and Part 100. The staff has prepared a proposed rulemaking to add a new section to 10 CFR Part 50 to provide an alternative set of requirements for treatment of structures, systems and components (SSCs), using a risk-informed categorization process to determine safety significance of the SSCs. These requirements can be voluntarily adopted by light-water reactor licensees and applicants. The proposed rule is based upon extensive interactions with stakeholders (including consideration of public comments on draft rule language made available on the NRC rulemaking web site), experience with pilot plants, and guidance development activities. The NRC staff expects that stakeholder input provided in response to the proposed rule issuance will be valuable and support the efforts to issue the final rule. (author)

  12. Needs for Risk Informing Environmental Cleanup Decision Making - 13613

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Ming; Moorer, Richard [U.S. Department of Energy, Washington, DC 20585 (United States)

    2013-07-01

    This paper discusses the needs for risk informing decision making by the U.S. Department of Energy (DOE) Office of Environmental Management (EM). The mission of the DOE EM is to complete the safe cleanup of the environmental legacy brought about from the nation's five decades of nuclear weapons development and production and nuclear energy research. This work represents some of the most technically challenging and complex cleanup efforts in the world and is projected to require the investment of billions of dollars and several decades to complete. Quantitative assessments of health and environmental risks play an important role in work prioritization and cleanup decisions of these challenging environmental cleanup and closure projects. The risk assessments often involve evaluation of performance of integrated engineered barriers and natural systems over a period of hundreds to thousands of years, when subject to complex geo-environmental transformation processes resulting from remediation and disposal actions. The requirement of resource investments for the cleanup efforts and the associated technical challenges have subjected the EM program to continuous scrutiny by oversight entities. Recent DOE reviews recommended application of a risk-informed approach throughout the EM complex for improved targeting of resources. The idea behind this recommendation is that by using risk-informed approaches to prioritize work scope, the available resources can be best utilized to reduce environmental and health risks across the EM complex, while maintaining the momentum of the overall EM cleanup program at a sustainable level. In response to these recommendations, EM is re-examining its work portfolio and key decision making with risk insights for the major sites. This paper summarizes the review findings and recommendations from the DOE internal reviews, discusses the needs for risk informing the EM portfolio and makes an attempt to identify topics for R and D in

  13. Needs for Risk Informing Environmental Cleanup Decision Making - 13613

    International Nuclear Information System (INIS)

    Zhu, Ming; Moorer, Richard

    2013-01-01

    This paper discusses the needs for risk informing decision making by the U.S. Department of Energy (DOE) Office of Environmental Management (EM). The mission of the DOE EM is to complete the safe cleanup of the environmental legacy brought about from the nation's five decades of nuclear weapons development and production and nuclear energy research. This work represents some of the most technically challenging and complex cleanup efforts in the world and is projected to require the investment of billions of dollars and several decades to complete. Quantitative assessments of health and environmental risks play an important role in work prioritization and cleanup decisions of these challenging environmental cleanup and closure projects. The risk assessments often involve evaluation of performance of integrated engineered barriers and natural systems over a period of hundreds to thousands of years, when subject to complex geo-environmental transformation processes resulting from remediation and disposal actions. The requirement of resource investments for the cleanup efforts and the associated technical challenges have subjected the EM program to continuous scrutiny by oversight entities. Recent DOE reviews recommended application of a risk-informed approach throughout the EM complex for improved targeting of resources. The idea behind this recommendation is that by using risk-informed approaches to prioritize work scope, the available resources can be best utilized to reduce environmental and health risks across the EM complex, while maintaining the momentum of the overall EM cleanup program at a sustainable level. In response to these recommendations, EM is re-examining its work portfolio and key decision making with risk insights for the major sites. This paper summarizes the review findings and recommendations from the DOE internal reviews, discusses the needs for risk informing the EM portfolio and makes an attempt to identify topics for R and D in integrated

  14. AECL experience in fuel channel inspection

    Energy Technology Data Exchange (ETDEWEB)

    Van Drunen, G. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Gunn, R. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada); Mayo, W.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Scott, D.A. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada)

    1999-06-01

    Inspection of CANDU fuel channels (FC) is performed to ensure safe and economic reactor operation. CANDU reactor FCs have features that make them a unique non-destructive testing (NDT) challenge. The thin, 4 mm pressure-tube wall means flaws down to about 0.1 mm deep must be reliably detected and characterized. This is one to two orders of magnitude smaller than is usually considered of significant concern for steel piping and pressure vessels. A second unique feature is that inspection sensors must operate in the reactor core--often within 20 cm of highly radioactive fuel. Work on inspection of CANDU reactor FCs at AECL dates back over three decades. In that time, AECL staff have provided equipment and conducted or supervised in-service inspections in about 250 FCs, in addition to over 8000 pre-service FCs. These inspections took place at every existing CANDU reactor except those in India and Romania. Early FC inspections focussed on measurement of changes in dimensions (gauging) resulting from exposure to a combination of neutrons, stress and elevated temperature. Expansion of inspection activities to include volumetric inspection (for flaws) started in the mid-1970s with the discovery of delayed hydride cracking in Pickering 3 and 4 rolled joints. Recognition of other types of flaw mechanisms in the 1980s led to further expansion in both pre-service and in-service inspections. These growing requirements, to meet regulatory as well as economic needs, led to the development of a wide spectrum of inspection technology that now includes tests for hydrogen concentration, structural integrity of core components, flaws, and dimensional change. This paper reviews current CANDU reactor FC inspection requirements. The equipment and techniques developed to satisfy these requirements are also described. The paper concludes with a discussion of work in progress in AECL aimed at providing state-of-the-art FC inspection services. (author)

  15. Risk-Informed Assessment Methodology Development and Application

    International Nuclear Information System (INIS)

    Sung Goo Chi; Seok Jeong Park; Chul Jin Choi; Ritterbusch, S.E.; Jacob, M.C.

    2002-01-01

    Westinghouse Electric Company (WEC) has been working with Korea Power Engineering Company (KOPEC) on a US Department of Energy (DOE) sponsored Nuclear Energy Research Initiative (NERI) project through a collaborative agreement established for the domestic NERI program. The project deals with Risk-Informed Assessment (RIA) of regulatory and design requirements of future nuclear power plants. An objective of the RIA project is to develop a risk-informed design process, which focuses on identifying and incorporating advanced features into future nuclear power plants (NPPs) that would meet risk goals in a cost-effective manner. The RIA design methodology is proposed to accomplish this objective. This paper discusses the development of this methodology and demonstrates its application in the design of plant systems for future NPPs. Advanced conceptual plant systems consisting of an advanced Emergency Core Cooling System (ECCS) and Emergency Feedwater System (EFWS) for a NPP were developed and the risk-informed design process was exercised to demonstrate the viability and feasibility of the RIA design methodology. Best estimate Loss-of-Coolant Accident (LOCA) analyses were performed to validate the PSA success criteria for the NPP. The results of the analyses show that the PSA success criteria can be met using the advanced conceptual systems and that the RIA design methodology is a viable and appropriate means of designing key features of risk-significant NPP systems. (authors)

  16. Development of a risk informed fire protection program

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, J.; McDevitt, B.; Sawyer, O.; Volk, M.A.; Drennan, J.; Sweely, C.

    2015-07-01

    Over the past decade, one of the largest challenges for the Nuclear Power Plant (NPP) Operator in the United States has been the implementation of risk-informed, performance-based (RI-PB) fire protection strategies into their fire protection program. Regardless of whether a utility decides to fully transition their licensing basis from deterministic to risk based, or if they simply complete a fire probabilistic risk assessment (FPRA) in order to augment their current program, it is clear that risk-informed, performance based fire protection strategies and the associated challenges are the growing trend in the United States and are here to stay. The experience of the nuclear industry in the United States with the implementation of RI-PB fire protection strategies can provide a great deal of insight for plants and utilities that follow, either by choice or necessity, a similar path. The similarities in the design of the United States and Spanish nuclear plants make these insights even more significant contributions to the strategy and planning for the Spanish fleet. The experience in United States will provide guidance to avoid similar missteps and better plan for the challenges of the transition process. As the Spanish fleet develops risk-informed and deterministic strategies to improve fire safety, an understanding of the challenges and lessons learned from the United States experience will save time and money. (Author)

  17. Risk-informed design of a pebble bed gas reactor

    International Nuclear Information System (INIS)

    Ritterbusch, Stanley; Dimitrijevic, Vesna; Simic Zdenko; Savkina Marina

    2003-01-01

    One of the major challenges to the successful deployment of new nuclear plants in the United States is the regulatory process, which is largely based on water-reactor design technology and operating experience. While ongoing and expected efforts to license new LWR designs are based primarily on current regulations, guidance, and past experience, the pre-application review of the gas-cooled Pebble Bed Modular Reactor (PBMR) has shown that efforts are being made to provide additional 'risk-informed' improvements to the licensing process. These improvements are aimed at resolving new design and regulatory issues using a plant-wide integrated evaluation method - state-of-the-art Probabilistic Risk Assessment - which addresses all significant design features and operating modes. The integrated PRA evaluation is supported by the usual deterministic design analyses, engineering judgments, and margins added to address uncertainties (i.e., defense-in-depth). The work performed for this paper was completed as part of the United States Department of Energy's Nuclear Energy Research Initiative. The purpose of this particular project was to develop the methods for a new 'highly risk-informed' design and regulatory process. In this work. PRA techniques were applied in order to provide an integrated and systematic analysis of the plant design, to quantify uncertainties and explicitly account for defense-in-depth features. This work concentrates on the application of the risk-informed principles to a new plant design such as the PBMR. The implementation example completed for this project included specification of the design configuration, use of the PRA to evaluate the design, and iterations to identify design changes that improve the overall level of safety and system reliability. This paper summarizes the new 'highly risk-informed' design process, the design of the PBMR, and the results obtained. These results, consistent with the known inherent safety features of a pebble

  18. A perspective on risk informed regulation and the maintenance rule

    International Nuclear Information System (INIS)

    In, Young H.

    2006-01-01

    Establishing a new regulatory framework for the future can be a complex and difficult task where the current regulatory framework and the past regulatory history must be reconciled. The nuclear regulatory framework will evolve over time, and it is in our best interest to make the right changes, whether the change is incremental or innovative. Basically, the risk-informed regulation (RIR) is an innovative change that must be made incrementally. Therefore, it is important that the changes to the framework are carefully evaluated and studied before the actual implementation. Otherwise, we may see unnecessary patches along the way that can be damaging to the regulatory integrity and the public confidence in the regulation. Even though, the United States has led the risk-informed regulation implementation during last decade, there were some instances where the well intended changes were not well planned and coordinated, resulting in loss of valuable time and resources that led to confusions among involved parties. The risk-informed regulation is an emerging trend worldwide, and Korea is one of the few that are ahead of the pack in embracing this innovative change in the regulation. To better understand and plan for RIR, we need to study both the well-established regulatory framework and the emerging regulatory framework. In addition, the recent trends in other regulatory framework similar to its own should be carefully studied. The reasons for any stagnations or barriers in other regulatory frameworks should be carefully noted and see if we share similar problems so that we can formulate better solutions. Blindly following others regulatory changes is not recommended, since our regulatory environment is unique in itself. We should take their inputs and lessons learned, but adopt them specifically to our industry needs and regulatory environment. This paper will attempt to provide a perspective on the risk-informing process of a nuclear plant by a brief look into two key

  19. Ultrasonic inspection development at HEDL

    International Nuclear Information System (INIS)

    Day, C.K.; Mech, S.J.; Michaels, T.E.; Dixon, N.E.

    1978-01-01

    Ultrasonic testing methods and equipment are being developed to support preservice and in-service inspection of selected FFTF welds. A digital computer system is employed in the analysis of both simulated FFTF pipe sections and plate specimens containing fatigue cracks. It is anticipated that test evaluation standards containing fatigue cracks will partially eliminate questions formerly associated with weld test calibration producers by providing natural cracks which follow grain boundaries and stress patterns resembling piping situ conditions. Studies have revealed that commercial transducers may satisfy LMFBR ultrasonic pipe inspection applications: The test system evaluation included transducers and wedge coupling and fluid coupling materials which exhibited acceptable performance at temperatures to 2300C. Results are presented that demonstrate the feasibility of ultrasonic inspection of components immersed in sodium at temperatures to 2600C. (UK)

  20. Risk informed regulation of nuclear facilities: Overview of the current status

    International Nuclear Information System (INIS)

    2005-02-01

    This report provides guidance on the use of risk information by regulatory bodies as part of an integrated decision making process. This addresses the way in which risk information is being used in decisions about safety issues at nuclear plants, sometimes referred to as risk informed decision making, and how risk information is being used by regulatory bodies as an input into the activities that they carry out, sometimes referred to as risk informed regulation

  1. A historical perspective of risk-informed regulation

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, P.L.

    1996-12-01

    In Federal studies, the process of using risk information is described as having two general components: (1) risk assessment - the application of credible scientific principles and statistical methods to develop estimates of the likely effects of natural phenomena and human factors and the characterization of these estimates in a form appropriate for the intended audience (e.g., agency decisionmakers, public); and (2) risk management - the process of weighing policy alternatives and selecting the most appropriate regulatory action, integrating the results of risk assessment with engineering data with social, economic, and political concerns to reach a decision. This paper discusses largely the second component.

  2. A historical perspective of risk-informed regulation

    International Nuclear Information System (INIS)

    Campbell, P.L.

    1996-01-01

    In Federal studies, the process of using risk information is described as having two general components: (1) risk assessment - the application of credible scientific principles and statistical methods to develop estimates of the likely effects of natural phenomena and human factors and the characterization of these estimates in a form appropriate for the intended audience (e.g., agency decisionmakers, public); and (2) risk management - the process of weighing policy alternatives and selecting the most appropriate regulatory action, integrating the results of risk assessment with engineering data with social, economic, and political concerns to reach a decision. This paper discusses largely the second component

  3. Risk-Informed SSCs Categorization: Elicitation Method of Expert's Opinion

    International Nuclear Information System (INIS)

    Hwang, Mee Jeong; Yang, Joon Eon; Kim, Kil Yoo

    2005-01-01

    The regulations have been performing by deterministic way since nuclear power plants have been operating. However, some SSCs identified as safety-significance by deterministic way, were turned out to be low or non safety-significant and some SSCs identified as non-safety significance were turned out to be high safety-significant according to the results of PSA. Considering these risk insights, Regulatory Guide 1.174 and 10CFR50.69 were drawn up, and we can re-categorize the SSCs according to their safety significance. Therefore, a study and an interest about the risk-informed SSCs re-categorization and treatment has been continued. The objective of this regulatory initiative is to adjust the scope of equipment subject to special regulatory treatment to better focus licensee and regulatory attention and resources on equipment that has safety significance. Current most regulations define the plant equipment necessary to meet deterministic regulatory basis as 'safety-related.' This equipment is subject to special treatment regulations. Other plant equipment is categorized as 'non-safety related,' and is not subject to a select number of special treatment requirement or a subset of those requirement. However, risk information is not a magic tool making a decision but a supporting tool to categorize SSCs. This is because only small parts of a plant are modeled in PSA model. Thus, engineering and deterministic judgments are also used for risk-informed SSCs categorization, and expert opinion elicitation is very important for risk-informed SSCs categorization. Therefore, we need a rational method to elicit the expert's opinions, and in this study, we developed a systematic method for expert elicitation to categorize the nuclear power plants' SSCs. Current states for SSCs categorization of the USA and the existing methods for expert elicitation were surveyed and more systematic way eliciting the expert opinions and combining was developed. To validate the developed method

  4. Feasibility of risk-informed technology for japanese nuclear power plants

    International Nuclear Information System (INIS)

    Yoshida, Tomoo; Fujioka, Terutaka; Kirimoto, Yorihiro; Ueda, Nobuyuki; Kinoshita, Izumi; Kashima, Koichi

    2000-01-01

    Risk-informed technology utilizes Probabilistic Safety Assessment for streamlining the maintenance of nuclear power plants. With this technology, plant components are categorized as either high or low-safety-significant components. The Maintenance requirements focuses on high safety-significant components and are relieved for low safety significant ones. This is expected to reduce plant cost while maintaining safety. We investigated especially risk-informed inservice inspection of piping in U.S. nuclear power plants in the interest of determining its feasibility for Japanese plants. Quantitative and qualitative RI-ISI methods were developed by the ASME/Westinghouse Owners Group and EPRI, respectively. These methods have been incorporated in the ASME Section 11 Code Cases and endorsed by the U.S. Nuclear Regulatory Commission. The quantitative method evaluates component segment risks in terms of pipe failure probability calculated with a probabilistic fracture mechanics(PFM) model and pipe failure impact categorization on core damage frequency(CDF) calculated with PSA. The qualitative method uses pipe failure potential categorization derived from the plant service experiences and pipe failure impact on CDF derived from the PSA insight. The PFM model is applicable only to failures from initial welding defects and stress corrosion cracking, therefore it does not cover such significant failure mechanisms found in nuclear power plants as corrosion or high-cycle fatigue, etc.. Thus, a qualitative failure potential categorization method was developed on the basis of the service experiences of the U.S. nuclear power plants, so that appropriate categorization rules must be developed on the service experiences in Japanese plants. Accordingly, we have devised a software framework with a computer-aided system for the selection of risk significant elements. This system consists of a piping failure database module, a piping failure analysis module, and a piping failure potential

  5. Risk-informed decision making during Bohunice NPP safety upgrading

    International Nuclear Information System (INIS)

    Lipar, M.; Muzikova, E.; Kubanyi, J.

    2001-01-01

    The paper summarizes some facts of risk-informed regulation developments within UJD regulatory environment. Based on national as well as international operating experience and indications resulted from PSA, Nuclear Regulatory Authority of the Slovak Republic (UJD) since its constituting in 1993 has devoted an effort to use PSA technology to support the regulatory policy in Slovakia. The PSA is considered a complement, not a substitute, to the deterministic approach. Suchlike integrated approach is used in decision making processes and the final decision on scope and priorities is based on it. The paper outlines risk insights used in the decision making process concerning Bohunice NPP safety upgrading and focuses on the role of PSA results in Gradual Reconstruction of Bohunice VI NPP. Besides, two other examples of the PSA results application to the decision making process are provided: the assessment of proposal of modifications to the main power supply diagram (incorporation of generator switches) and the assessment of licensee request for motor generator AOT (Allowable Outage Time) extension. As an example of improving support of Bohunice V-2 risk-informed operations, concept of AOT calculations and Bohunice V-2 Risk Monitor Project are briefly described. (author)

  6. Inspection of Candu Nuclear Reactor Fuel Channels

    International Nuclear Information System (INIS)

    Baron, J.; Jarvis, G.N.; Dolbey, M.P.; Hayter, D.M.

    1986-01-01

    The Channel Inspection and Gauging Apparatus of Reactors (CIGAR) is a fully atomated, remotely operated inspection system designed to perform multi-channel, multi-task inspection of CANDU reactor fuel channels. Ultrasonic techniques are used for flaw detection, (with a sensitivity capable of detecting a 0.075 mm deep notch with a signal to noise ratio of 10 dB) and pressure tube wall thickness and diameter measurements. Eddy currrent systems are used to detect the presence of spacers between the coaxial pressure tube and calandria tube, as well as to measure their relative spacing. A servo-accelerometer is used to estimate the sag of the fuel channels. This advanced inspection system was commissioned and declared in service in September 1985. The paper describes the inspection systems themselves and discussed the results achieved to-date. (author) [pt

  7. Risk informed decision making. Topical issues paper no. 1

    International Nuclear Information System (INIS)

    Niehaus, F.; Szikszai, T.

    2001-01-01

    To date, probabilistic safety assessments (PSAs) have been performed for more than 200 nuclear power plants (NPPs) worldwide and are under various stages of development for most of the remaining NPPs. The state-of-the-art is to have a full scope Level 2 PSA (including external events and low power and shutdown) which is maintained as a 'living PSA' with regular updating. Modern computer technology allows frequent recalculations of the PSA to evaluate the impact of changes in operation or design and allows use of the PSA in the form of safety or risk monitors. There is a general agreement, as documented in various IAEA Safety Standards, that the deterministic approach to nuclear safety should be complemented by a probabilistic approach. Though PSAs have been used extensively in the past, it was usually limited to a variety of applications on a case by case basis as deemed necessary or useful. There is now a recent development led by the USA, and followed by several other countries, to move to a much expanded use of PSA in what is termed 'risk informed decision making'. The main driving force behind this movement is the expectation that the use of risk insights can result in both improved safety and a reduction in unnecessary regulatory requirements, hence leading to a more efficient use of resources for NPP operators and the regulatory authority. One of the key challenges in truly risk informed decision making is the reconciliation of PSA results and insights with traditional deterministic analysis. This is particularly true when it comes to defence in depth and safety margins. PSA results often conflict with deterministic insights. If a method of reconciling these conflicts is not defined, then risk informed can become deterministic plus PSA. This results in PSA being an additional layer of requirements rather than a tool for optimized decision making. Alternatively, if PSA information is always used to override deterministic considerations, then that is a 'risk

  8. The contribution of inspection to the management of risk

    Energy Technology Data Exchange (ETDEWEB)

    Baron, J. [Folville Consulting Inc., Ontario (Canada)

    2016-01-15

    Over the recent several years, the nuclear power industry has moved to designing in-service inspection programs based on plant risk analyses. This has led to significant reduction in the amount of inspections required thereby reducing the cost of the inspection process itself but, more significantly, the cost due to plant downtime. Inspection has no impact on the consequence of failure but, rather, mitigates risk through reduction in the probability of failure. In so doing, it is important to consider the reliability of inspections, how reliability may be improved through deployment of automation but consideration must also be given to human factors with respect to achieving and reporting correct results. (author)

  9. Risk-informed assessment of degraded containment structures

    International Nuclear Information System (INIS)

    Spencer, B.W.; Kunsman, D.M.; Graves, H.L.

    2003-01-01

    As nuclear power plants age, a number of degradation mechanisms may begin to affect the ability of critical containment structures to prevent radiation release during a severe accident. A research program is underway to quantify the effects of various types of containment degradation in a risk-informed manner. In this paper, corrosion is assumed to occur in the liner of a reinforced concrete containment at a 'typical' U.S. pressurized water reactor nuclear power plant, and its effect is investigated. Latin hypercube sampling is used in conjunction with finite element models of a typical steel-lined reinforced concrete containment to generate overpressurization fragilities of the containment with and without corrosion. An existing probabilistic risk assessment model of the plant is then used with these fragilities to determine the increase in risk caused by the corrosion. (author)

  10. Development of risk-informed assessment (RIA) design methodology

    International Nuclear Information System (INIS)

    Ji, S. K.; Park, S. J.; Park, B. R.; Kim, M. R.; Choi, C. J.

    2001-01-01

    It has been assessed that the capital cost for future nuclear power plants needs to be reduced on the order of 35% to 40% for Advanced Light Water Reactors such as KNGR and System 80+. Such reduction in the capital cost will require a fundamental re-evaluation of the industry standards and regulatory basis under which nuclear plants are designed and licensed. The objective of this study is to develop the risk-informed assessment (RIA) design methodology for future nuclear power plants. In order to meet this objective, the design simplification method is developed and RIA design methodology exercised for conceptual system. For the methodology verification, simplified conceptual ECCS and feedwater system are developed, then LOCA sensitivity analyses and agressive secondary cooldown analyses for these systems are performed. In addition, the probability safety assessment (PSA) model for LOCA is developed and the validation of RIA design methodology is demonstrated

  11. Use of importance measures in risk-informed regulatory applications

    International Nuclear Information System (INIS)

    Cheok, Michael C.; Parry, Gareth W.; Sherry, Richard R.

    1998-01-01

    The use of importance measures to analyze PRA results is discussed. Commonly used importance measures are defined. Some issues that have been identified as potentially limiting their usefulness are addressed, namely: there is no simple relationship between importance measures evaluated at the single component level and those evaluated at the level of a group of components, and, as a result, some of the commonly used importance measures are not realistic measures of the sensitivity of the overall risk to parameter value changes; and, importance measures do not typically take into account parameter uncertainties which raises the question of the robustness of conclusions drawn from importance analyses. The issues are explored in the context of both ranking and categorization of structures, systems, and components (SSCs) with respect to risk-significance and safety-significance for use in risk-informed regulatory analyses

  12. Regulatory approach to risk informed decision making in India

    International Nuclear Information System (INIS)

    Chande, S.K.; Koley, J.

    2001-01-01

    Atomic Energy Regulatory Board (AERB), the authority for licensing and monitoring safety in Indian Nuclear Power Plants (NPPs), makes use of insights gained from PSA together with the results of the other deterministic analyses in taking decisions regarding the acceptability of the safety of the NPPs. PSA provides an estimation of risks; it also gives information on a balanced design by revealing interaction between engineered features and weak areas in a design. For regulatory use, PSA needs to be carried out using standardized methodology and state of the art technology. PSA helps regulators in taking faster and consistent decisions. Keeping in mind the limitations associated with PSA study, AERB has decided to adopt risk-informed decision making in regulatory licensing process. This paper describes the AERB policy regarding PSA and gives an overview of the experience in this area. (author)

  13. Risk-informing special treatment requirements for reactors

    International Nuclear Information System (INIS)

    McKenna, E.M.; Reed, T.A.

    2001-01-01

    The U.S. Nuclear Regulatory Commission (NRC) is proposing to make regulatory changes to the scope of structures, systems, and components (SSCs) requiring special treatment. ''Special treatment requirements'' refers to those specific examples of regulations that are applied in order to provide a high degree of assurance that SSC will be capable of performing their intended functions when needed. The current scope of SSCs covered by the special treatment requirements governing commercial nuclear reactors is deterministically based and stems primarily from the evaluation of selected design basis events, as described in updated final safety analysis reports (UFSARs). This regulatory framework provides reasonable assurance of no undue risk to the health and safety of the public. However, recent advances in technology, coupled with operating reactor experience, have suggested that an alternative approach that would use a risk-informed process for evaluating SSC safety significance, would, in turn, result in a more focused determination of which SSCs should receive special treatment requirements. (author)

  14. Risk-informed, performance-based safety-security interface

    International Nuclear Information System (INIS)

    Mrowca, B.; Eltawila, F.

    2012-01-01

    Safety-security interface is a term that is used as part of the commercial nuclear power security framework to promote coordination of the many potentially adverse interactions between plant security and plant safety. Its object is to prevent the compromise of either. It is also used to describe the concept of building security into a plant's design similar to the long standing practices used for safety therefore reducing the complexity of the operational security while maintaining or enhancing overall security. With this in mind, the concept of safety-security interface, when fully implemented, can influence a plant's design, operation and maintenance. It brings the approach use for plant security to one that is similar to that used for safety. Also, as with safety, the application of risk-informed techniques to fully implement and integrate safety and security is important. Just as designers and operators have applied these techniques to enhance and focus safety, these same techniques can be applied to security to not only enhance and focus the security but also to aid in the implementation of effective techniques to address the safety-security interfaces. Implementing this safety-security concept early within the design process can prevent or reduce security vulnerabilities through low cost solutions that often become difficult and expensive to retrofit later in the design and/or post construction period. These security considerations address many of the same issues as safety in ensuring that the response of equipment and plant personnel are adequate. That is, both safety and security are focused on reaching safe shutdown and preventing radiological release. However, the initiation of challenges and the progression of actions in response these challenges and even the definitions of safe shutdown can be considerably different. This paper explores the techniques and limitations that are employed to fully implement a risk-informed, safety-security interface

  15. Improvement of infrastructure for risk-informed regulation

    International Nuclear Information System (INIS)

    2012-01-01

    Improvement of the infrastructure of probabilistic safety assessment (PSA) is essential to the risk-informed regulation for nuclear power plants. JNES conducted update of initiating event frequencies and improvement of the method for uncertainty analysis to enhance the technology bases of PSA in 2011. Furthermore, JNES improved the human reliability analysis method and the reliability analysis method for digital reactor protection systems. JNES estimated initiating event frequencies both for power and shutdown operation based on the recent operating experiences in Nuclear Power Plants (NPPs) of Japan using the hierarchical Bayesian method. As for improvement of the uncertainty analysis method, JNES conducted trial analyses using SOKC (State-Of-Knowledge Correlation) for the representative PWR plant and BWR plant of Japan. The study on the advanced HRA method with operator cognitive action model was conducted to improve a quality of HRA. The study on analyses of 'defense in depth' and 'diversity' for introducing digital instrumentation and control (I and C) systems was conducted. In order to ensure the quality of PSA, JNES conducted a peer review of a representative Japanese BWR plant PSA by the professional PSA engineers from the U.S. in order to extract to improve quality of PSA, and made an effort to develop the procedures of internal fire PSA. JNES participated in OECD/NEA PRISME and FIRE project to obtain the latest information and data to validate and improve the fire propagation analysis codes and the parameters for fire PSA as well. Furthermore, JNES studied schemes for the endorsement and application in the risk-informed regulation of PSA standards established by Atomic Energy Society of Japan. (author)

  16. Improvement of infrastructure for risk-informed regulation

    International Nuclear Information System (INIS)

    Muta, Hitoshi; Tanji, Junichi; Kondo, Keisuke; Uchida, Tsuyoshi; Ito, Tomomichi

    2011-01-01

    Improvement of the infrastructure of probabilistic safety assessment (PSA) is essential to the risk-informed regulation for nuclear power plants. JNES conducted update of initiating event frequency and improvement of method for uncertainty analysis to enhance the technology bases of PSA in 2010. Furthermore, JNES improved human reliability assessment method and reliability assessment method for digital reactor protection systems. JNES estimated initiating event frequencies both for power and shutdown operation based on the recent operating experiences in NPPs of Japan using hierarchical Bayesian method. As for improvement of uncertainty analysis method, JNES conducted trial analysis using SOKC (State-Of-Knowledge Correlation) for representative PWR and BWR of Japan. The study on the advanced HRA method with operator cognitive action model was conducted. The study on reliability analysis method for digital reactor protection systems using Bayesian Network Method was conducted. In order to ensure the quality of PSA, JNES studied requirements and methods for PSA peer review via the preparation of peer review for PSA of a representative Japanese BWR plant conducted by JNES. As an effort to develop the procedures of internal fire PSA and internal flooding PSA, trial analyses were conducted to grasp the risk level cause by fire and flooding in nuclear power plants. JNES participated in OECD/NEA PRISME and FIRE project to obtain the latest information and data to validate and improve the fire propagation analysis codes and the parameters for fire PSA. Furthermore, JNES studies schemes for endorsement and application in risk-informed regulation of PSA standards established by Atomic Energy Society of Japan. (author)

  17. Planning for risk-informed/performance-based fire protection at nuclear power plants. Final report

    International Nuclear Information System (INIS)

    Najafi, B.; Parkinson, W.J.; Lee, J.A.

    1997-12-01

    This document presents a framework for discussing issues and building consensus towards use of fire modeling and risk technology in nuclear power plant fire protection program implementation. The plan describes a three-phase approach: development of core technologies, implementation of methods, and finally, case studies and pilot applications to verify viability of such methods. The core technologies are defined as fire modeling, fire and system tests, use of operational data, and system and risk techniques. The implementation phase addresses the programmatic issues involved in implementing a risk-informed/performance-based approach in an integrated approach with risk/performance measures. The programmatic elements include: (1) a relationship with fire codes and standards development as defined by the ongoing effort of NFPA for development of performance-based standards; (2) the ability for NRC to undertake inspection and enforcement; and (3) the benefit to utilities in terms of cost versus safety. The case studies are intended to demonstrate applicability of single issue resolution while pilot applications are intended to check the applicability of the integrated program as a whole

  18. Opinions of the well-informed persons about the nuclear reactor facility periodical inspection

    International Nuclear Information System (INIS)

    Aeba, Yoichi; Ishikawa, Michio; Enomoto, Toshiaki; Oomori, Katsuyoshi

    2005-01-01

    Falsifications of self-inspection records in the shrouds and of leakage rates for containment vessels at TEPCO nuclear power plants destroyed public trust in nuclear safety. The Nuclear Reactor Regulation Law and Electric Utility Law were amended to enhance the nuclear safety regulation system. The major improvements are that operators are legally required to conduct inspection (periodical operator inspection) and recording and keeping inspection results. The operator performs 'periodical operator inspection' regularly, and Nuclear and Industrial Safety Agency (NISA) performs periodical inspection' about particularly important facilities/function in safety. Sixteen opinions of well-informed persons about the nuclear reactor facility periodical inspection were presented in this special number. Interval of periodical inspection less than thirteen months was disputed. Maintenance activities should be more rationalized based on risk information. (T. Tanaka)

  19. Additive Manufacturing Infrared Inspection

    Science.gov (United States)

    Gaddy, Darrell; Nettles, Mindy

    2015-01-01

    The Additive Manufacturing Infrared Inspection Task started the development of a real-time dimensional inspection technique and digital quality record for the additive manufacturing process using infrared camera imaging and processing techniques. This project will benefit additive manufacturing by providing real-time inspection of internal geometry that is not currently possible and reduce the time and cost of additive manufactured parts with automated real-time dimensional inspections which deletes post-production inspections.

  20. Irradiation effects and the duplication of detected flaws in service

    International Nuclear Information System (INIS)

    Mager, T.R.

    1976-01-01

    ASME Code procedure for evaluating the acceptability of flaws detected during in-service inspection is revised. Critical crack size for instability is proposed as criteria for detected flaws in operating plants

  1. The Preliminary Review for the Cross-Cutting Issues in the US Nuclear Regulatory Inspection Framework

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Suk; Jung, Dae Wook [Future and Challenges Inc., Seoul (Korea, Republic of); Cho, Nam Chul [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2008-10-15

    The research for the development of risk-informed and performance-based regulatory inspection is ongoing in KINS. In the USNRC, the cross-cutting issue is one of the main components the risk-informed and performance-based regulatory inspection process as shown in figure 1, which is named as ROP (Reactor Oversight Process). The following three cross-cutting areas implicitly affect all of the safety cornerstones in ROP. In this study, the preliminary review for the inspection practices of cross-cutting issues in the US and Korean safety regulatory system were performed. The elements of the cross-cutting issues were recently modified to emphasize the importance of safety culture, and the graded approach was applied for the inspection of cross-cutting issues in USNRC. The graded approach for the inspection of cross-cutting issues will be also needed to Korean safety regulatory system in the future.

  2. The Preliminary Review for the Cross-Cutting Issues in the US Nuclear Regulatory Inspection Framework

    International Nuclear Information System (INIS)

    Lee, Yong Suk; Jung, Dae Wook; Cho, Nam Chul

    2008-01-01

    The research for the development of risk-informed and performance-based regulatory inspection is ongoing in KINS. In the USNRC, the cross-cutting issue is one of the main components the risk-informed and performance-based regulatory inspection process as shown in figure 1, which is named as ROP (Reactor Oversight Process). The following three cross-cutting areas implicitly affect all of the safety cornerstones in ROP. In this study, the preliminary review for the inspection practices of cross-cutting issues in the US and Korean safety regulatory system were performed. The elements of the cross-cutting issues were recently modified to emphasize the importance of safety culture, and the graded approach was applied for the inspection of cross-cutting issues in USNRC. The graded approach for the inspection of cross-cutting issues will be also needed to Korean safety regulatory system in the future

  3. Optimizing pre-service inspection data

    International Nuclear Information System (INIS)

    Mullins, L.E.; Harrison, J.M.

    1986-01-01

    The phenomenon of intergranular stress corrosion cracking (IGSCC) in nuclear power plant piping systems has been the single biggest factor in an evolution that has changed and continues to change in-service inspection practices and philosophy throughout the industry. In-service inspection has been found to deal with several distinct phases of the problem. At the onset, existing technology was demonstrated to be unable to detect IGSCC adequately. This inability to detect IGSCC was soon overcome. However, it immediately pointed out the difficulties associated with the discrimination between IGSCC and other harmless metallurgical conditions. On the heels of detection and discrimination came problems associated with determining crack size and the monitoring of overlayed flaws. A wealth of information has been written on all phases of IGSCC; however, one particular aspect has as of yet seen little attention. With an increasing number of plants choosing to replace flawed pipe, the pre-service inspection of the replaced piping demands increased attention. The lessons learned through inspection for IGSCC need again to be applied to the replacement piping. Through increased attention at installation, many of the difficulties associated with proper inservice inspection may be reduced or eliminated, thereby realizing an economy in outage scheduling, personnel exposure, and, overall, a more reliable in-service examination

  4. Risk Information Seeking among U.S. and Dutch Residents. An Application of the model of Risk Information Seeking and Processing

    NARCIS (Netherlands)

    ter Huurne, E.F.J.; Griffin, Robert J.; Gutteling, Jan M.

    2009-01-01

    The model of risk information seeking and processing (RISP) proposes characteristics of individuals that might predispose them to seek risk information. The intent of this study is to test the model’s robustness across two independent samples in different nations. Based on data from the United

  5. Change of risk information disclosure in annual report. Before and after earthquake disaster

    International Nuclear Information System (INIS)

    Ueno, Takefumi

    2011-01-01

    This research examines how risk information disclosure is changing in annual report before and after East Japan Great Earthquake Disaster. Company voluntary disclose risk information in annual report. Manager can decide a style and items of risk information. This paper explores risk information disclosures of Tokyo Electric Power Company, Chubu Power Electric Company, Kansai Electric Power Company and Toyota Motor Corporation. The managers except Tokyo Electric Company are likely to disclose own catastrophe risk before the disaster. However, they do not try to reduce their risk. Corporations' risk information do not link with own risk management. (author)

  6. Toward introduction of risk informed safety regulation. Nuclear Safety Commission taskforce's interim report

    International Nuclear Information System (INIS)

    2006-01-01

    Nuclear Safety Commission's taskforce on 'Introduction of Safety Regulation Utilizing Risk Information' completed the interim report on its future subjects and directions in December 2005. Although current safety regulatory activities have been based on deterministic approach, this report shows the risk informed approach is expected to be very useful for making nuclear safety regulation and assurance activities reasonable and also for appropriate allocation of regulatory resources. For introduction of risk informed regulation, it also recommends pileups of experiences with gradual introduction and trial of the risk informed approach, improvement of plant maintenance rules and regulatory requirements utilizing risk information, and establishment of framework to assure quality of risk evaluation. (T. Tanaka)

  7. Which Type of Risk Information to Use for Whom? Moderating Role of Outcome-Relevant Involvement in the Effects of Statistical and Exemplified Risk Information on Risk Perceptions.

    Science.gov (United States)

    So, Jiyeon; Jeong, Se-Hoon; Hwang, Yoori

    2017-04-01

    The extant empirical research examining the effectiveness of statistical and exemplar-based health information is largely inconsistent. Under the premise that the inconsistency may be due to an unacknowledged moderator (O'Keefe, 2002), this study examined a moderating role of outcome-relevant involvement (Johnson & Eagly, 1989) in the effects of statistical and exemplified risk information on risk perception. Consistent with predictions based on elaboration likelihood model (Petty & Cacioppo, 1984), findings from an experiment (N = 237) concerning alcohol consumption risks showed that statistical risk information predicted risk perceptions of individuals with high, rather than low, involvement, while exemplified risk information predicted risk perceptions of those with low, rather than high, involvement. Moreover, statistical risk information contributed to negative attitude toward drinking via increased risk perception only for highly involved individuals, while exemplified risk information influenced the attitude through the same mechanism only for individuals with low involvement. Theoretical and practical implications for health risk communication are discussed.

  8. Risk-informed design guidance for future reactor systems

    International Nuclear Information System (INIS)

    Delaney, Michael J.; Apostolakis, George E.; Driscoll, Michael J.

    2005-01-01

    Future reactor designs face an uncertain regulatory environment. It is anticipated that there will be some level of probabilistic insights in the regulations and supporting regulatory documents for Generation-IV nuclear reactors. Central to current regulations are design basis accidents (DBAs) and the general design criteria (GDC), which were established before probabilistic risk assessments (PRAs) were developed. These regulations implement a structuralist approach to safety through traditional defense in depth and large safety margins. In a rationalist approach to safety, accident frequencies are quantified and protective measures are introduced to make these frequencies acceptably low. Both approaches have advantages and disadvantages and future reactor design and licensing processes will have to implement a hybrid approach. This paper presents an iterative four-step risk-informed methodology to guide the design of future-reactor systems using a gas-cooled fast reactor emergency core cooling system as an example. This methodology helps designers to analyze alternative designs under potential risk-informed regulations and to anticipate design justifications the regulator may require during the licensing process. The analysis demonstrated the importance of common-cause failures and the need for guidance on how to change the quantitative impact of these potential failures on the frequency of accident sequences as the design changes. Deliberation is an important part of the four-step methodology because it supplements the quantitative results by allowing the inclusion in the design choice of elements such as best design practices and ease of online maintenance, which usually cannot be quantified. The case study showed that, in some instances, the structuralist and the rationalist approaches were inconsistent. In particular, GDC 35 treats the double-ended break of the largest pipe in the reactor coolant system with concurrent loss of offsite power and a single

  9. 14 CFR 91.409 - Inspections.

    Science.gov (United States)

    2010-01-01

    ... instructions for their use; (3) Enough housing and equipment for necessary disassembly and proper inspection of... rotorcraft unless the replacement times for life-limited parts specified in the aircraft specifications, type... time in service, calendar times, or cycles of operation accumulated under the previous program must be...

  10. Improvement of remote control system of automatic ultrasonic equipment for inspection of reactor pressure vessel

    International Nuclear Information System (INIS)

    Cheong, Yong Moo; Jung, H. K.; Joo, Y. S.; Koo, K. M.; Hyung, H.; Sim, C. M.; Gong, U. S.; Kim, S. H.; Lee, J. P.; Rhoo, H. C.; Kim, M. S.; Ryoo, S. K.; Choi, C. H.; Oh, K. I.

    1999-12-01

    One of the important issues related to the nuclear safety is in-service inspection of reactor pressure vessel (RPV). A remote controlled automatic ultrasonic method is applied to the inspection. At present the automatic ultrasonic inspection system owned by KAERI is interrupted due to degradation of parts. In order to resume field inspection new remote control system for the equipment was designed and installed to the existing equipment. New ultrasonic sensors and their modules for RPV inspection were designed and fabricated in accordance with the new requirements of the inspection codes. Ultrasonic sensors were verified for the use in the RPV inspection. (author)

  11. Improvement of remote control system of automatic ultrasonic equipment for inspection of reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Yong Moo; Jung, H. K.; Joo, Y. S.; Koo, K. M.; Hyung, H.; Sim, C. M.; Gong, U. S.; Kim, S. H.; Lee, J. P.; Rhoo, H. C.; Kim, M. S.; Ryoo, S. K.; Choi, C. H.; Oh, K. I

    1999-12-01

    One of the important issues related to the nuclear safety is in-service inspection of reactor pressure vessel (RPV). A remote controlled automatic ultrasonic method is applied to the inspection. At present the automatic ultrasonic inspection system owned by KAERI is interrupted due to degradation of parts. In order to resume field inspection new remote control system for the equipment was designed and installed to the existing equipment. New ultrasonic sensors and their modules for RPV inspection were designed and fabricated in accordance with the new requirements of the inspection codes. Ultrasonic sensors were verified for the use in the RPV inspection. (autho0008.

  12. A new importance measure for risk-informed decision making

    International Nuclear Information System (INIS)

    Borgonovo, E.; Apostolakis, G.E.

    2000-01-01

    Recently, several authors pointed out that the traditional importance measures had limitations. In this study, the problem through an analysis at the parameter level was investigated and a new measure was introduced. The measure was based on small parameter variations and is capable of accounting for the importance of a group of components/parameters. The definition, computational steps, and an application of a new importance measure for risk-informed decision making were presented here. Unlike traditional importance measures, differential importance measure (DIM) deals with changes in the various parameters that determine the unavailability/unreliability of a component, e.g., failure rates, common-cause failure rates, individual human errors. The importance of the component unavailability/unreliability can be calculated from the importance of the parameters. DIM can be calculated for the frequency of initiating events, while risk achievement worth (RAW) is limited to binary events, e.g., component unavailability. The changes in parameters are 'small'. This is more realistic than the drastic assumption in RAW that the component is always down. DIM is additive. This allows the evaluation of the impact of changes, such as the relaxation of quality assurance requirements, which affect groups of parameters, e.g., the failure rates of a group of pumps. (M.N.)

  13. Risk-informed inservice test activities at the NRC

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, D.; Cheok, M.; Hsia, A.

    1996-12-01

    The operational readiness of certain safety-related components is vital to the safe operation of nuclear power plants. Inservice testing (IST) is one of the mechanisms used by licensees to ensure this readiness. In the past, the type and frequency of IST have been based on the collective best judgment of the NRC and industry in an ASME Code consensus process and NRC rulemaking process. Furthermore, IST requirements have not explicitly considered unique component and system designs and contribution to overall plant risk. Because of the general nature of ASME Code test requirements and non-reliance on risk estimates, current IST requirements may not adequately emphasize testing those components that are most important to safety and may overly emphasize testing of less safety significant components. Nuclear power plant licensees are currently interested in optimizing testing by applying resources in more safety significant areas and, where appropriate, reducing measures in less safety-significant areas. They are interested in maintaining system availability and reducing overall maintenance costs in ways that do not adversely affect safety. The NRC has been interested in using probabilistic, as an adjunct to deterministic, techniques to help define the scope, type and frequency of IST. The development of risk-informed IST programs has the potential to optimize the use of NRC and industry resources without adverse affect on safety.

  14. Study on default setting for risk-informed regulation

    International Nuclear Information System (INIS)

    Jang, S.C.; Ha, J.J.; Jung, W.D.; Jeong, K.S.; Han, S.H.

    1998-12-01

    Both performing and validating a detailed risk analysis of a complex system are costly and time-consuming undertakings. With the increased use of probabilistic safety analysis (PSA) in regulatory decision making, both regulated parties and regulators have generally favored the use of defaults, because they can greatly facilitate the process of performing a PSA in the first place as well as the process of reviewing and verifying the PSA. The use of defaults may also ensure more uniform standards of PSA quality. However, regulatory agencies differ in their approaches to the use of default values, and the implications of these differences are not yet well understood. Moreover, large heterogeneity among licensees makes it difficult to set suitable defaults. This study focus on the development of model for setting defaults in order to achieve more applicability of risk-informed regulation. In particular, explored are the effects of different levels of conservatism in setting defaults, and their implications for the crafting of regularity incentives. (author). 17 refs., 1 tab

  15. Background risk information to assist in risk management decision making

    International Nuclear Information System (INIS)

    Hammonds, J.S.; Hoffman, F.O.; White, R.K.; Miller, D.B.

    1992-10-01

    The evaluation of the need for remedial activities at hazardous waste sites requires quantification of risks of adverse health effects to humans and the ecosystem resulting from the presence of chemical and radioactive substances at these sites. The health risks from exposure to these substances are in addition to risks encountered because of the virtually unavoidable exposure to naturally occurring chemicals and radioactive materials that are present in air, water, soil, building materials, and food products. To provide a frame of reference for interpreting risks quantified for hazardous waste sites, it is useful to identify the relative magnitude of risks of both a voluntary and involuntary nature that are ubiquitous throughout east Tennessee. In addition to discussing risks from the ubiquitous presence of background carcinogens in the east Tennessee environment, this report also presents risks resulting from common, everyday activities. Such information should, not be used to discount or trivialize risks from hazardous waste contamination, but rather, to create a sensitivity to general risk issues, thus providing a context for better interpretation of risk information

  16. Risk-informed inservice test activities at the NRC

    International Nuclear Information System (INIS)

    Fischer, D.; Cheok, M.; Hsia, A.

    1996-01-01

    The operational readiness of certain safety-related components is vital to the safe operation of nuclear power plants. Inservice testing (IST) is one of the mechanisms used by licensees to ensure this readiness. In the past, the type and frequency of IST have been based on the collective best judgment of the NRC and industry in an ASME Code consensus process and NRC rulemaking process. Furthermore, IST requirements have not explicitly considered unique component and system designs and contribution to overall plant risk. Because of the general nature of ASME Code test requirements and non-reliance on risk estimates, current IST requirements may not adequately emphasize testing those components that are most important to safety and may overly emphasize testing of less safety significant components. Nuclear power plant licensees are currently interested in optimizing testing by applying resources in more safety significant areas and, where appropriate, reducing measures in less safety-significant areas. They are interested in maintaining system availability and reducing overall maintenance costs in ways that do not adversely affect safety. The NRC has been interested in using probabilistic, as an adjunct to deterministic, techniques to help define the scope, type and frequency of IST. The development of risk-informed IST programs has the potential to optimize the use of NRC and industry resources without adverse affect on safety

  17. Risk Informed Optimization of Nuclear Instrumentation for Emergency Conditions

    International Nuclear Information System (INIS)

    Knoll, Alexander

    2013-06-01

    Emergency conditions after a nuclear accident are different in each case and cannot be predicted accurately. The accident at TMI did not contaminate the environment. The accident at Chernobyl had a large, early release of nuclear contamination, widely dispersed over many countries. Although there was no large, early release of contamination at Fukushima Daiichi, the timeline of the accident included days of later contamination of various degrees of severity. A large amount of the contamination has been released to the ocean and an exclusion zone still exists around the station. In all of these accidents there were no adequate radiation monitoring systems distant from the origin point that could provide accurate status to the authorities and the local population. In the recent years a number of new nuclear monitoring systems have been implemented or are under development to be installed in areas that might be exposed to nuclear contamination in emergencies. Based on the risk informed optimization methodology, this paper provides recommendations for selecting the quantity and type of instrumentation, the location and sampling of data, and the real-time processing of information. (authors)

  18. The development of a nuclear accident risk information system

    International Nuclear Information System (INIS)

    Jeong, J. T.; Jeong, W. D.

    2001-01-01

    The computerized system NARIS (Nuclear Accident Risk Information System) was developed in order to support the estimation of health effects and the establishment the effective risk reduction strategies. Using the system, we can analyze the distribution of health effects easily by displaying the results on the digital map of the site. Also, the thematic mapping allows the diverse analyses of the distribution of the health effects. The NARIS can be used in the emergency operation facilities in order to analyze the distribution of the health effects resulting from the severe accidents of a nuclear power plant. Also, the rapid analysis of the health effect is possible by storing the health effect results in the form of a database. Therefore, the staffs of the emergency operation facilities can establish the rapid and effective emergency response strategies. The module for the optimization of the costs and benefits and the decision making support will be added. The technical support for the establishment of the optimum and effective emergency response strategies will be possible using this system

  19. Generic Reliability-Based Inspection Planning for Fatigue Sensitive Details

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Straub, Daniel; Faber, Michael Havbro

    2005-01-01

    of fatigue sensitive details in fixed offshore steel jacket platforms and FPSO ship structures. Inspection and maintenance activities are planned such that code based requirements to the safety of personnel and environment for the considered structure are fulfilled and at the same time such that the overall......The generic approach for planning of in-service NDT inspections is extended to cover the case where the fatigue load is modified during the design lifetime of the structure. Generic reliability-based inspection planning has been developed as a practical approach to perform inspection planning...... expected costs for design, inspections, repairs and failures are minimized. The method is based on the assumption of “no-finds” of cracks during inspections. Each fatigue sensitive detail is categorized according to their type of details (SN curves), FDF values, RSR values, inspection, repair and failure...

  20. Pressure vessel integrity and weld inspection procedure

    International Nuclear Information System (INIS)

    Solomon, K.A.; Okrent, D.; Kastenberg, W.E.

    1975-01-01

    The primary objective of this paper is to develop a simple methodology which, when coupled with existing observations on pressure vessel behavior, provides an inter-relation between pressure vessel integrity, and the parameters of the in-service inspection program, including inspection sample size, frequency and efficiency. A modified Markov process is employed and a computer code was written to obtain numerical results. The Markov process mathematically describes the following physical events. In a nuclear reactor pressure vessel weld, some defects may exist prior to the zeroth inspection (i.e., prior to vessel operation). During the zeroth inspection and repair processes, some of these defects are removed. During the first cycle of vessel operation, the existing defects may grow and some new defects may be generated. Those defects that are found at the first (and succeeding) inspection interval and warrant repair, are repaired. The above process continues through several operating cycles to the end of vessel life. During any inspection, only a portion of the welds may be inspected, and with less than perfect efficiency

  1. Automated Inspection of Aircraft

    Science.gov (United States)

    1998-04-01

    This report summarizes the development of a robotic system designed to assist aircraft inspectors by remotely deploying non-destructive inspection (NDI) sensors and acquiring, processing, and storing inspection data. Carnegie Mellon University studie...

  2. Optimising import phytosanitary inspection

    NARCIS (Netherlands)

    Surkov, I.

    2007-01-01

    Keywords: quarantine pest, plant health policy, optimization, import phytosanitary inspection, ‘reduced checks’, optimal allocation of resources, multinomial logistic regression, the Netherlands World trade is a major vector of spread of quarantine plant pests. Border phytosanitary inspection

  3. Approaches to cancer assessment in EPA's Integrated Risk Information System.

    Science.gov (United States)

    Gehlhaus, Martin W; Gift, Jeffrey S; Hogan, Karen A; Kopylev, Leonid; Schlosser, Paul M; Kadry, Abdel-Razak

    2011-07-15

    The U.S. Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS) Program develops assessments of health effects that may result from chronic exposure to chemicals in the environment. The IRIS database contains more than 540 assessments. When supported by available data, IRIS assessments provide quantitative analyses of carcinogenic effects. Since publication of EPA's 2005 Guidelines for Carcinogen Risk Assessment, IRIS cancer assessments have implemented new approaches recommended in these guidelines and expanded the use of complex scientific methods to perform quantitative dose-response assessments. Two case studies of the application of the mode of action framework from the 2005 Cancer Guidelines are presented in this paper. The first is a case study of 1,2,3-trichloropropane, as an example of a chemical with a mutagenic mode of carcinogenic action thus warranting the application of age-dependent adjustment factors for early-life exposure; the second is a case study of ethylene glycol monobutyl ether, as an example of a chemical with a carcinogenic action consistent with a nonlinear extrapolation approach. The use of physiologically based pharmacokinetic (PBPK) modeling to quantify interindividual variability and account for human parameter uncertainty as part of a quantitative cancer assessment is illustrated using a case study involving probabilistic PBPK modeling for dichloromethane. We also discuss statistical issues in assessing trends and model fit for tumor dose-response data, analysis of the combined risk from multiple types of tumors, and application of life-table methods for using human data to derive cancer risk estimates. These issues reflect the complexity and challenges faced in assessing the carcinogenic risks from exposure to environmental chemicals, and provide a view of the current trends in IRIS carcinogenicity risk assessment. Copyright © 2011. Published by Elsevier Inc.

  4. A new risk-informed design and regulatory process

    International Nuclear Information System (INIS)

    Apostolakis, George E.; Golay, Michael W.; Camp, Allen L.; Duran, Felicia A.; Finnicum, David; Ritterbusch, Stanley E.

    2001-01-01

    The overall purpose of the new approach, termed Risk-Informed Regulation, is to formulate a method of regulation that is logically consistent and devised so that both the reactor designer and regulator can work together in obtaining systems able to produce economical electricity safely. In this new system the traditional tools (deterministic and probabilistic analyses, tests and expert judgement) and treatments (defense-in-depth, conservatism) of safety regulation would still be employed, but the logic governing their use would be reversed from the current treatment. In the new treatment, probabilistic risk analysis (PRA) would be used as the paramount decision support tool, taking advantage of its ability to integrate all of the elements of system performance and to represent the uncertainties in the results. The latter is the most important reason for this choice, as the most difficult part of safety regulation is the treatment of uncertainties, not the assurance of expected performance. The scope of the PRA would be made as large as that of the reactor system, including all of its performance phenomena. The models and data of the PRA would be supported by deterministic analytical results, and data to the extent feasible. However, as in the current regulatory system, the models and data of the PRA would require being complemented by subjective judgements where the former were inadequate. All of these elements play important roles in the current decision-making structure; the main departure from current practice would be making all of these treatments explicit within the PRA, therefore, decreasing the frequency of sometimes arbitrary judgments. In the intended sense the PRA would be used as a vehicle for stating the beliefs of the designer and regulatory decision-maker; the foundation of their decisions. Thus, the PRA should be viewed as a Bayesian decision tool, and be used in order to take advantage of its capabilities in integration and inclusion of

  5. Approaches to cancer assessment in EPA's Integrated Risk Information System

    International Nuclear Information System (INIS)

    Gehlhaus, Martin W.; Gift, Jeffrey S.; Hogan, Karen A.; Kopylev, Leonid; Schlosser, Paul M.; Kadry, Abdel-Razak

    2011-01-01

    The U.S. Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS) Program develops assessments of health effects that may result from chronic exposure to chemicals in the environment. The IRIS database contains more than 540 assessments. When supported by available data, IRIS assessments provide quantitative analyses of carcinogenic effects. Since publication of EPA's 2005 Guidelines for Carcinogen Risk Assessment, IRIS cancer assessments have implemented new approaches recommended in these guidelines and expanded the use of complex scientific methods to perform quantitative dose-response assessments. Two case studies of the application of the mode of action framework from the 2005 Cancer Guidelines are presented in this paper. The first is a case study of 1,2,3-trichloropropane, as an example of a chemical with a mutagenic mode of carcinogenic action thus warranting the application of age-dependent adjustment factors for early-life exposure; the second is a case study of ethylene glycol monobutyl ether, as an example of a chemical with a carcinogenic action consistent with a nonlinear extrapolation approach. The use of physiologically based pharmacokinetic (PBPK) modeling to quantify interindividual variability and account for human parameter uncertainty as part of a quantitative cancer assessment is illustrated using a case study involving probabilistic PBPK modeling for dichloromethane. We also discuss statistical issues in assessing trends and model fit for tumor dose-response data, analysis of the combined risk from multiple types of tumors, and application of life-table methods for using human data to derive cancer risk estimates. These issues reflect the complexity and challenges faced in assessing the carcinogenic risks from exposure to environmental chemicals, and provide a view of the current trends in IRIS carcinogenicity risk assessment.

  6. Technical objectives of inspection

    International Nuclear Information System (INIS)

    Sorenson, R.J.; Stewart, K.B.; Schneider, R.A.

    1976-01-01

    The various technical objectives of inspection are discussed in a very general manner. The discussion includes how the inspection function is related to the assumed threat, the various degrees of assurance and reliance on criteria, and the hierarchy of assurance which is obtained from the various types or levels of inspection

  7. Software Formal Inspections Guidebook

    Science.gov (United States)

    1993-01-01

    The Software Formal Inspections Guidebook is designed to support the inspection process of software developed by and for NASA. This document provides information on how to implement a recommended and proven method for conducting formal inspections of NASA software. This Guidebook is a companion document to NASA Standard 2202-93, Software Formal Inspections Standard, approved April 1993, which provides the rules, procedures, and specific requirements for conducting software formal inspections. Application of the Formal Inspections Standard is optional to NASA program or project management. In cases where program or project management decide to use the formal inspections method, this Guidebook provides additional information on how to establish and implement the process. The goal of the formal inspections process as documented in the above-mentioned Standard and this Guidebook is to provide a framework and model for an inspection process that will enable the detection and elimination of defects as early as possible in the software life cycle. An ancillary aspect of the formal inspection process incorporates the collection and analysis of inspection data to effect continual improvement in the inspection process and the quality of the software subjected to the process.

  8. Randomization of inspections

    International Nuclear Information System (INIS)

    Markin, J.T.

    1989-01-01

    As the numbers and complexity of nuclear facilities increase, limitations on resources for international safeguards may restrict attainment of safeguards goals. One option for improving the efficiency of limited resources is to expand the current inspection regime to include random allocation of the amount and frequency of inspection effort to material strata or to facilities. This paper identifies the changes in safeguards policy, administrative procedures, and operational procedures that would be necessary to accommodate randomized inspections and identifies those situations where randomization can improve inspection efficiency and those situations where the current nonrandom inspections should be maintained. 9 refs., 1 tab

  9. MINAC, A new radiographic inspection capability

    International Nuclear Information System (INIS)

    Lapides, M.E.; Schonberg, R.

    1983-01-01

    In service, radiographic inspection of thick section, metallic components has historically been limited to the capabilities of radioisotopic sources such as cobalt and iridium. Although practical in many applications, these sources tend to be restricted by output intensity, by resolution obtainable, and by the physical size and weight of necessary transport shielding. In nuclear plant applications, any radiography is also frequently inhibited by the presence of a radiation background from activated corrosion products on the inspection object which may fog the film before the desired exposure is achieved. In recognition of these limitations and the need for improved capability in the conduct of mandated ten-year inspection of U.S. nuclear plant components such as reactor coolant pumps, pressure vessel nozzles and valve bodies, the Electric Power Research Institute (EPRI) undertook the development of a high energy, X-ray device appropriate for in service inspection of thick section (up to approximately 30 cm of steel) components. The development was conducted by Schonberg Radiation (U.S.A). The product, MINAC, a miniaturized linear accelerator system, has been in use in many plant inspections since April 1981. This paper describes the development and typical applications of MINAC

  10. Study on institutionalization of risk-informed performance-based regulation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, M. G.; Hong, S. Y.; Seo, M. R. [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    2003-02-15

    In this study, for the institutionalization of risk informed and performance based regulation in Korea, the latest technical movements of overseas countries are examined and reviewed. And the issues that was found when license change petition using risk information was submitted in Korean regulatory body are reviewed. Based on these review, the applicable areas to domestic situation will be found and proposed. This study can contribute to setting up the proper direction for the institutionalization of risk informed and performance based regulation.

  11. Crack Characterisation for In-service Inspection Planning - An Update

    Energy Technology Data Exchange (ETDEWEB)

    Waale, Jan [lnspecta Technology AB, Stockholm (Sweden)

    2006-05-15

    One important factor to optimize the NDT equipment and NDT procedure is to know the characteristics of the specific defects being sought for in each case. Thus, access is necessary to reliable morphology data of defects from all possible degradation mechanisms in all existing materials of the components that are subject to the NDT. In 1994 the Swedish Nuclear Power Inspectorate (SKI) initiated a project for compiling crack morphology data based on systematic studies of cracks that have been observed in different plants (nuclear and non-nuclear) in order to determine typical as well as more extreme values of e.g. orientation, width and surface roughness. Although, a large number of identified cracking incidents was covered by the work it was recognised that further studies were needed to increase the data base, and thereby getting more confidence in the use of different crack characteristic data for NDT development and qualification purposes. That is the major reason why the present work was initiated. A thorough review of the SKI archives was performed aiming to find useful material from the time period between 1994 and today to compile complementary data and produce an update. Furthermore, older material was collected and evaluated. Thus, the data cover cracking found within the time period 1977-2003. In addition, useful material was supplied by the Swedish nuclear power plants. The evaluation and presentation of the results are similar to the 1994 study, with a few exceptions. The base for the evaluation is failure analysis reports, where the crack morphology parameters were measured from photos on cracked surfaces or cross sections through cracks. The resulting data were divided into seven groups depending on the cracking mechanism/material group combination. The data groups are: IGSCC in austenitic stainless steels; IGSCC in nickel base alloys; IDSCC in nickel base weld metal; TGSCC in austenitic stainless steels Thermal fatigue in austenitic stainless steels; Mechanical fatigue; and Solidification cracking in weld metal. The evaluated parameters were divided into visually detectable and metallurgical parameters, which need to be evaluated from a cross-section. The visually detectable parameters are; location, orientation and shape in surface direction and finally the number of cracks in the cracked region. The metallurgical parameters are; orientation and shape in the through thickness direction, macroscopic branching, crack tip radius, crack surface roughness, crack width and finally discontinuous appearance. The morphology parameters were statistically processed and the results are presented as minimum, maximum. mean, median and scatter values for each data group, both in tables and in various graphs. Finally each morphology parameter is compared between the seven data groups. A brief description of typical characteristics of each data group is given below. Most IGSCC develop next to welds with straight or winding cracks oriented almost parallel to the weld. Single cracking is most common but occasionally two cracks are formed on each side of the weld. In the through thickness direction IGSCC is typically winding or lightly bend and macroscopic branching is rare. The surface roughness is normally on a grain size magnitude and the cracks are particularly narrow providing secondary corrosion is small. Similar characteristics to IGSCC in austenitic stainless steels may be expected. However, cracking close to weld are less frequent and macroscopic branching is more common for IGSCC in nickel base alloys compared to austenitic stainless steels. Typically IDSCC is winding or straight, single cracking in the weld metal transverse to the weld. In the through thickness direction IDSCC cause typically winding, non branched cracks with large surface roughness due to course solidification microstructure. The crack width often shows large variation along the crack and a width close to zero at the surface intersection is common. Typically, TGSCC is branched both in surface and through thickness direction. The crack orientation shows a random distribution and the number of cracks is large. The crack surface roughness show low values and the crack width is typically medium range compared with the other groups. A large number of randomly oriented cracks are typical for thermal fatigue. However, single or few cracks with similar orientation occur. In the through thickness direction straight, non-branched cracking oriented in right angle to the surface is most common. The crack surface roughness is of medium range and larger than for mechanical fatigue. Typically straight, single cracking oriented parallel with stress raisers is common for mechanical fatigue. In the through thickness direction most cracks are straight, non branched and oriented in right angle to the surface. The crack surface roughness is the smallest and the correlation length the highest of all groups. Solidification cracks occur equally frequent parallel as well as transversal to the weld. A large number of cracks are common. In the through thickness direction the cracks seldom show branching and is most often oriented close to 90 deg to the surface. The crack surface roughness is in the medium range and far below the one for IDSCC, which was not expected.

  12. Crack Characterisation for In-service Inspection Planning - An Update

    International Nuclear Information System (INIS)

    Waale, Jan

    2006-05-01

    One important factor to optimize the NDT equipment and NDT procedure is to know the characteristics of the specific defects being sought for in each case. Thus, access is necessary to reliable morphology data of defects from all possible degradation mechanisms in all existing materials of the components that are subject to the NDT. In 1994 the Swedish Nuclear Power Inspectorate (SKI) initiated a project for compiling crack morphology data based on systematic studies of cracks that have been observed in different plants (nuclear and non-nuclear) in order to determine typical as well as more extreme values of e.g. orientation, width and surface roughness. Although, a large number of identified cracking incidents was covered by the work it was recognised that further studies were needed to increase the data base, and thereby getting more confidence in the use of different crack characteristic data for NDT development and qualification purposes. That is the major reason why the present work was initiated. A thorough review of the SKI archives was performed aiming to find useful material from the time period between 1994 and today to compile complementary data and produce an update. Furthermore, older material was collected and evaluated. Thus, the data cover cracking found within the time period 1977-2003. In addition, useful material was supplied by the Swedish nuclear power plants. The evaluation and presentation of the results are similar to the 1994 study, with a few exceptions. The base for the evaluation is failure analysis reports, where the crack morphology parameters were measured from photos on cracked surfaces or cross sections through cracks. The resulting data were divided into seven groups depending on the cracking mechanism/material group combination. The data groups are: IGSCC in austenitic stainless steels; IGSCC in nickel base alloys; IDSCC in nickel base weld metal; TGSCC in austenitic stainless steels Thermal fatigue in austenitic stainless steels; Mechanical fatigue; and Solidification cracking in weld metal. The evaluated parameters were divided into visually detectable and metallurgical parameters, which need to be evaluated from a cross-section. The visually detectable parameters are; location, orientation and shape in surface direction and finally the number of cracks in the cracked region. The metallurgical parameters are; orientation and shape in the through thickness direction, macroscopic branching, crack tip radius, crack surface roughness, crack width and finally discontinuous appearance. The morphology parameters were statistically processed and the results are presented as minimum, maximum. mean, median and scatter values for each data group, both in tables and in various graphs. Finally each morphology parameter is compared between the seven data groups. A brief description of typical characteristics of each data group is given below. Most IGSCC develop next to welds with straight or winding cracks oriented almost parallel to the weld. Single cracking is most common but occasionally two cracks are formed on each side of the weld. In the through thickness direction IGSCC is typically winding or lightly bend and macroscopic branching is rare. The surface roughness is normally on a grain size magnitude and the cracks are particularly narrow providing secondary corrosion is small. Similar characteristics to IGSCC in austenitic stainless steels may be expected. However, cracking close to weld are less frequent and macroscopic branching is more common for IGSCC in nickel base alloys compared to austenitic stainless steels. Typically IDSCC is winding or straight, single cracking in the weld metal transverse to the weld. In the through thickness direction IDSCC cause typically winding, non branched cracks with large surface roughness due to course solidification microstructure. The crack width often shows large variation along the crack and a width close to zero at the surface intersection is common. Typically, TGSCC is branched both in surface and through thickness direction. The crack orientation shows a random distribution and the number of cracks is large. The crack surface roughness show low values and the crack width is typically medium range compared with the other groups. A large number of randomly oriented cracks are typical for thermal fatigue. However, single or few cracks with similar orientation occur. In the through thickness direction straight, non-branched cracking oriented in right angle to the surface is most common. The crack surface roughness is of medium range and larger than for mechanical fatigue. Typically straight, single cracking oriented parallel with stress raisers is common for mechanical fatigue. In the through thickness direction most cracks are straight, non branched and oriented in right angle to the surface. The crack surface roughness is the smallest and the correlation length the highest of all groups. Solidification cracks occur equally frequent parallel as well as transversal to the weld. A large number of cracks are common. In the through thickness direction the cracks seldom show branching and is most often oriented close to 90 deg to the surface. The crack surface roughness is in the medium range and far below the one for IDSCC, which was not expected

  13. In-service inspection of pool type research reactors

    International Nuclear Information System (INIS)

    Rajamani, K.

    2002-01-01

    In the case of Apsara Reactor, it has been proposed to carry out major modifications in the near future. It is planned to modify the core suitably with a heavy water reflector tank to demonstrate the Multiple Purpose Research Reactor concept. The core structure will be a stationary one and will be located at the 'B' position of the pool. The modified reactor will be operated at 1 MW power level. Suitable methodologies are evolved for carrying out a planned ISI for this modified reactor

  14. In-service ultrasonic inspection of nuclear reactor pressure vessels

    International Nuclear Information System (INIS)

    Prepechal, J.; Sulc, J.

    1982-01-01

    Ultrasonic tests of pressure vessels for WWER 440 reactors, type 213 V, are carried out partly manually and partly by test equipment. The inner surface of the pressure vessel is tested using device REACTORTEST TRC which is fully mobile. The outer surface of the cylindrical parts and bottoms of the body is tested using handling equipment permanently in-built under the pressure vessel and dismountable testing heads. A set of these heads may be used for two reactor units. The testing equipment REACTORTEST TRC is equipped with a TRC 800 ultrasound device. The equipment for testing the outer surface of the vessel operates with the UDAR 16 ultrasound apparatus to which may be simultaneously connected 10 ultrasound probes and six probes for acoustic feedback. The whole system of ultrasonic tests makes possible a first-rate and reliable volume control of the whole pressure vessel and all points where cracks may originate and grow. (Z.M.)

  15. Boiler inspection manipulator for Torness Power Station

    International Nuclear Information System (INIS)

    Carrey, R.T.A.; Playle, M.J.

    1996-01-01

    In-service inspection at Torness Advanced Gas-cooled Reactor is achieved, via penetrations above and below the core area and boilers and through eight circulator penetrations for inspection of the sub-diagrid area. A manipulator is described which can access the area above the reactor core via any of these eight peripheral penetrations. The design and fabrication of the manipulator has led to innovation with a number of possible solutions being tendered. In reactor deployment of the successful design is expected in early 1997. (UK)

  16. A study on the effect of flaw detection probability assumptions on risk reduction achieved by non-destructive inspection

    International Nuclear Information System (INIS)

    Cronvall, O.; Simola, K.; Männistö, I.; Gunnars, J.; Alverlind, L.; Dillström, P.; Gandossi, L.

    2012-01-01

    Leakages and ruptures of piping components lead to reduction or loss of the pressure retaining capability of the system, and thus contribute to the overall risk associated with nuclear power plants. In-service inspection (ISI) aims at verifying that defects are not present in components of the pressure boundary or, if defects are present, ensuring that these are detected before they affect the safe operation of the plant. Reliability estimates of piping are needed e.g., in probabilistic safety assessment (PSA) studies, risk-informed ISI (RI-ISI) applications, and other structural reliability assessments. Probabilistic fracture mechanics models can account for ISI reliability, but a quantitative estimate for the latter is needed. This is normally expressed in terms of probability of detection (POD) curves, which correlate the probability of detecting a flaw with flaw size. A detailed POD curve is often difficult (or practically impossible) to obtain. If sufficient risk reduction can be shown by using simplified (but reasonably conservative) POD estimates, more complex PODs are not needed. This paper summarises the results of a study on the effect of piping inspection reliability assumptions on failure probability using structural reliability models. The main interest was to investigate whether it is justifiable to use a simplified POD curve. Further, the study compared various structural reliability calculation approaches for a set of analysis cases. The results indicate that the use of a simplified POD could be justifiable in RI-ISI applications.

  17. Insight into the Earthquake Risk Information Seeking Behavior of the Victims: Evidence from Songyuan, China

    Directory of Open Access Journals (Sweden)

    Shasha Li

    2017-03-01

    Full Text Available Efficient risk communication is a vital way to reduce the vulnerability of individuals when facing emergency risks, especially regarding earthquakes. Efficient risk communication aims at improving the supply of risk information and fulfilling the need for risk information by individuals. Therefore, an investigation into individual-level information seeking behavior within earthquake risk contexts is very important for improved earthquake risk communication. However, at present there are very few studies that have explored the behavior of individuals seeking earthquake risk information. Under the guidance of the Risk Information Seeking and Processing model as well as relevant practical findings using the structural equation model, this study attempts to explore the main determinants of an individual’s earthquake risk information seeking behavior, and to validate the mediator effect of information need during the seeking process. A questionnaire-based survey of 918 valid respondents in Songyuan, China, who had been hit by a small earthquake swarm, was used to provide practical evidence for this study. Results indicated that information need played a noteworthy role in the earthquake risk information seeking process, and was detected both as an immediate predictor and as a mediator. Informational subjective norms drive the seeking behavior on earthquake risk information through both direct and indirect approaches. Perceived information gathering capacity, negative affective responses and risk perception have an indirect effect on earthquake risk information seeking behavior via information need. The implications for theory and practice regarding risk communication are discussed and concluded.

  18. Risk-informed technology developments for nuclear power plants within the ASME in 2000-2001

    International Nuclear Information System (INIS)

    Wesley Rowley, C.; Balkey, K.R.

    2001-01-01

    The purpose of this paper is to provide information on developments within the ASME to support risk-informing NRC regulations for nuclear power plants. This paper builds on a publication at ICONE-8 that discussed ASME risk-informed nuclear power plant initiatives, both in Research and in Codes and Standards, particularly those related to risk-informing Part 50 of the 10 CFR (Code of federal regulations). During the past year, the ASME BNCS formed a Task Force to focus the Society's efforts to support risk-informing 10 CFR Part 50. Key efforts underway that are guided by the task force include finalizing the ASME PRA (probability risk assessment) Standard, developing a Code Case to risk-inform the repair, replacement, and modification activities for ASME components, and developing a Code Case to risk-inform the safety classification of pressure boundary components. Several other initiatives are also under investigation such as introducing risk insights into other ASME nuclear codes and standards supported by appropriate research and technical basis information. Supplementary information will also be provided to update an initial high level plan of ASME risk-informed initiatives for nuclear power plants that was presented at ICONE-8, including plans to communicate these risk-informed technology developments to the public. The authors included and acknowledged contributions from several other cognizant members of the ASME BNCS (board on nuclear codes standards) Task Group on RIP50 in the paper. (authors)

  19. Optical fiber inspection system

    Science.gov (United States)

    Moore, Francis W.

    1987-01-01

    A remote optical inspection system including an inspection head. The inspection head has a passageway through which pellets or other objects are passed. A window is provided along the passageway through which light is beamed against the objects being inspected. A plurality of lens assemblies are arranged about the window so that reflected light can be gathered and transferred to a plurality of coherent optical fiber light guides. The light guides transfer the light images to a television or other image transducer which converts the optical images into a representative electronic signal. The electronic signal can then be displayed on a signal viewer such as a television monitor for inspection by a person. A staging means can be used to support the objects for viewing through the window. Routing means can be used to direct inspected objects into appropriate exit passages for accepted or rejected objects. The inspected objects are advantageously fed in a singular manner to the staging means and routing means. The inspection system is advantageously used in an enclosure when toxic or hazardous materials are being inspected.

  20. 46 CFR 153.812 - Inspection for Certificate of Inspection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Inspection for Certificate of Inspection. 153.812... CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Testing and Inspection § 153.812 Inspection for Certificate of Inspection. The rules governing the...

  1. Technical regulation of nondestructive inspection

    International Nuclear Information System (INIS)

    1995-01-01

    It starts with the explanation of definition of nondestructive inspection and qualifications for a inspection. It lists the technical regulations of nondestructive inspections which are radiographic testing, ultrasonic flaw detecting test, liquid penetrant test, magnetic particle inspection, eddy current test visual inspection and leakage test.

  2. Study on communicating risk information obtained from PSA within nuclear power plants

    International Nuclear Information System (INIS)

    Nunogane, Nobuaki; Onoue, Akira; Kojima, Shigeo

    2000-01-01

    In this study, the communication of PSA information in nuclear power plants (NPPs), namely, how the risk information obtained from the probabilistic safety assessment (PSA) should be presented and communicated to plant personnel, was examined assuming that the safety management system based on the risk information was introduced to NPPs. This is called PSA communication. First, when risk-informed safety management is to be introduced into NPPs, plant personnel should have sufficient related knowledge. In order to provide such knowledge to the personnel through training, risk information is classified into three types: basic information, detailed information and task information. A hierarchical risk information summary for reporting, coordinating and communicating tasks is proposed. In this summary, the concerns of those who have received the information are placed at the top and the related risk information positioned below. At the same time, and by way of a trial, the risk information relating to on-line maintenance (OLM) is prepared. In order to enhance the safety-consciousness and the safety of the entire plant, specific plans such as 'risk tags' which indicate the safety significance of equipment is proposed. Finally, a guideline providing examination procedures for developing detailed PSA communication plans is introduced. (author)

  3. Health products inspection

    International Nuclear Information System (INIS)

    Stoltz, M.

    2009-01-01

    To protect public health, the Health Products Inspection is a public service mission where the application of regulations concerning activities on human health products and cosmetic products is verified. This mission permits a global approach to assess the health products risk-based benefit and, in monitoring by laboratory testing and by on site inspections, to verify their compliance with appropriate regulations. The seventy five inspectors perform about eight hundred inspections per year, in France and abroad. These inspections are related to data provided in the health products assessment and also to manufacturing and delivery practices. The French inspection body is also involved in the training of foreign inspectors and in the harmonization of national, European and international practices either for operators than for the competent authorities. (author)

  4. Discussion of a method for providing general risk information by linking with the nuclear information

    International Nuclear Information System (INIS)

    Shobu, Nobuhiro; Yokomizo, Shirou; Umezawa, Sayaka

    2004-06-01

    'Risk information navigator (http://www.ricotti.jp/risknavi/)', an internet tool for arousing public interest and fostering people's risk literacy, has been developed as the contents for the official website of Techno Community Square 'RICOTTI' (http://www.ricotti.jp) at TOKAI village. In this report we classified the risk information into the fields, Health/Daily Life', 'Society/Crime/Disaster' and Technology/Environment/Energy', for the internet tool contents. According to these categories we discussed a method for providing various risk information on general fields by linking with the information on nuclear field. The web contents are attached to this report with the CD-R media. (author)

  5. Working session 2: Tubing inspection

    International Nuclear Information System (INIS)

    Guerra, J.; Tapping, R.L.

    1997-01-01

    This session was attended by delegates from 10 countries, and four papers were presented. A wide range of issues was tabled for discussion. Realizing that there was limited time available for more detailed discussion, three topics were chosen for the more detailed discussion: circumferential cracking, performance demonstration (to focus on POD and sizing), and limits of methods. Two other subsessions were organized: one dealt with some challenges related to the robustness of current inspection methods, especially with respect to leaving cracked tubes in service, and the other with developing a chart of current NDE technology with recommendations for future development. These three areas are summarized in turn, along with conclusions and/or recommendations. During the discussions there were four presentations. There were two (Canada, Japan) on eddy current probe developments, both of which addressed multiarray probes that would detect a range of flaws, one (Spain) on circumferential crack detection, and one (JRC, Petten) on the recent PISC III results

  6. Preliminary conceptual design of inspection and maintenance for KALIMER reactor system

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Kim, Seok Hun; Yoo, Bong

    2000-08-01

    In-service inspection and maintenance are very important for improving the safety and availability of nuclear power plants. The conceptual requirements of in-service inspection and maintenance should be reflected in the earlier design process for the verification of the plant operability and reliability. In this report the fundamental approaches of the inspection and maintenance for KALIMER are established to ensure the structural integrity and operability for KALIMER. The general strategy and methodology of maintenance and inspection for the reactor system and components are proposed and described for satisfying the intents of the section XI, division 3, of ASME code and considering the design characteristics of KALIMER.

  7. Information needs and risk perception as predictors of risk information seeking

    NARCIS (Netherlands)

    ter Huurne, E.F.J.; Gutteling, Jan M.

    2008-01-01

    This paper introduces a theoretical framework that describes the importance of public's information sufficiency, risk perception, and self-efficacy as predictors of intended risk information seeking behaviour. Based on theoretical assumptions, measurement instruments for relevant concepts were

  8. A Tutorial on Probablilistic Risk Assessement and its Role in Risk-Informed Decision Making

    Science.gov (United States)

    Dezfuli, Homayoon

    2010-01-01

    This slide presentation reviews risk assessment and its role in risk-informed decision making. It includes information on probabilistic risk assessment, typical risk management process, origins of risk matrix, performance measures, performance objectives and Bayes theorem.

  9. Runway Inspection by RPAS

    Directory of Open Access Journals (Sweden)

    Stanislav Absolon

    2015-10-01

    Full Text Available This article discusses the use of the RPAS for the inspection of the airport operating areas. The paper compares the current process of the inspection of the airport operating areas by the airport staff with the possibilities which are offered by the use of the modern technology RPAS. The following text also describes how to inspect airport operating areas by the RPAS, specific technical possibilities and the applicable technical solutions. Furthermore there are variants of piloting the RPAS, comparing usable equipment, equipment for video recording and the possibility of using thermal imaging camera in the article.

  10. Magnetic rubber inspection (MRI)

    International Nuclear Information System (INIS)

    Carro, L.

    1997-01-01

    Magnetic Rubber Inspection (MRI) was developed to inspect for small cracks and flaws encountered in high performance aircraft. A formula of very fine magnetic particles immersed in a room temperature curing rubber is catalysed and poured into dams (retainers) on the surface of the part to be inspected. Inducing a magnetic field then causes the particles to be drawn to discontinuities in the component under test. These indicating particles are held to the discontinuity by magnetic attraction, as the rubber cures. The solid rubber cast (Replica) is then removed and examined under a microscope for indicating lines of particle concentrations. 3 refs., 6 figs

  11. Automated PCB Inspection System

    Directory of Open Access Journals (Sweden)

    Syed Usama BUKHARI

    2017-05-01

    Full Text Available Development of an automated PCB inspection system as per the need of industry is a challenging task. In this paper a case study is presented, to exhibit, a proposed system for an immigration process of a manual PCB inspection system to an automated PCB inspection system, with a minimal intervention on the existing production flow, for a leading automotive manufacturing company. A detailed design of the system, based on computer vision followed by testing and analysis was proposed, in order to aid the manufacturer in the process of automation.

  12. Review of current practices and requirements for the inspection of prestressed concrete pressure vessels

    International Nuclear Information System (INIS)

    Reimann, K.J.

    1980-12-01

    Code requirements for pre- and in-service inspection of prestressed concrete pressure vessels as utilized in gas-cooled reactors are reviewed and compared with practices and experiences during construction, commissioning, and operation of such reactors. The pre-service inspection relies heavily on embedded instrumentation for measurements of stresses, temperatures, and displacements. The same instrumentation is later used for in-service surveillance, which additionally includes visual examination of exposed surfaces, monitoring of tendon conditions, and measurement of tendon loads. Improvement of present monitoring instrumentation and/or techniques, rather than development of new in-service inspection methods, is recommended

  13. The effect of non-financial risk information on the evaluation of implied cost of capitals

    OpenAIRE

    Norio Kitagawa; Hyonok Kim; Masatoshi Goto

    2011-01-01

    The purpose of this paper is to examine the effect of voluntary disclosure of `business risk' information (hereafter referred to as `risk information' ), which is a significant determinant of the information environment, on estimating the cost of capital. Recently, some studies indicate that the reliability of the cost of capital estimation differs according to the accounting standards and the information environment of the firm (e.g. Chen et al., 2004; Easton and Monahan, 2005). On the basis...

  14. Reproducibility problems of in-service ultrasonic testing results

    International Nuclear Information System (INIS)

    Honcu, E.

    1974-01-01

    The reproducibility of the results of ultrasonic testing is the basic precondition for its successful application in in-service inspection of changes in the quality of components of nuclear power installations. The results of periodic ultrasonic inspections are not satisfactory from the point of view of reproducibility. Regardless, the ultrasonic pulse-type method is suitable for evaluating the quality of most components of nuclear installations and often the sole method which may be recommended for inspection with regard to its technical and economic aspects. (J.B.)

  15. Manipulator arm for a nuclear reactor vessel inspection device

    International Nuclear Information System (INIS)

    1980-01-01

    A manipulator arm for a reactor vessel in-service inspection apparatus is adapted to transport a transducer array for ultrasonic examination of welds at any point in the vessel. The removal of the inspection device from the reactor vessel in an emergency presents a problem where a relatively long manipulator arm is used. This invention provides an improved arm with means for changing the normal orientation of the arm to a shorter one to permit safe removal of the inspection device from the reactor vessel. (author)

  16. Potential for ultrasonic inspection of heat exchanger tubes

    International Nuclear Information System (INIS)

    Ward, M.J.

    1980-01-01

    Preliminary results of a program to develop an ultrasonic inspection method for heat-exchanger tubes, to be used as alternative or complementary to eddy-curent testing were sufficiently promising to warrant further study. Problems were encountered in adapting a standard commercial transducer and a custom-made transducer to provide full 360 degree coverage of an area for in-service inspection, but it might be possible to overcome these problems. The results showed it might prove impossible to design a transducer to handle the tight U-bends in some heat exchangers. The most promising area of application for ultrasonic inspection was found to be around the tubesheet. (DN)

  17. Inspection of Nuclear Power Plant Containment Structures

    Energy Technology Data Exchange (ETDEWEB)

    Graves, H.L.; Naus, D.J.; Norris, W.E.

    1998-12-01

    Safety-related nuclear power plant (NPP) structures are designed to withstand loadings from a number of low-probability external and interval events, such as earthquakes, tornadoes, and loss-of-coolant accidents. Loadings incurred during normal plant operation therefore generally are not significant enough to cause appreciable degradation. However, these structures are susceptible to aging by various processes depending on the operating environment and service conditions. The effects of these processes may accumulate within these structures over time to cause failure under design conditions, or lead to costly repair. In the late 1980s and early 1990s several occurrences of degradation of NPP structures were discovered at various facilities (e.g., corrosion of pressure boundary components, freeze- thaw damage of concrete, and larger than anticipated loss of prestressing force). Despite these degradation occurrences and a trend for an increasing rate of occurrence, in-service inspection of the safety-related structures continued to be performed in a somewhat cursory manner. Starting in 1991, the U.S. Nuclear Regulatory Commission (USNRC) published the first of several new requirements to help ensure that adequate in-service inspection of these structures is performed. Current regulatory in-service inspection requirements are reviewed and a summary of degradation experience presented. Nondestructive examination techniques commonly used to inspect the NPP steel and concrete structures to identify and quantify the amount of damage present are reviewed. Finally, areas where nondestructive evaluation techniques require development (i.e., inaccessible portions of the containment pressure boundary, and thick heavily reinforced concrete sections are discussed.

  18. Wheel inspection system environment.

    Science.gov (United States)

    2008-11-18

    International Electronic Machines Corporation (IEM) has developed and is now marketing a state-of-the-art Wheel Inspection System Environment (WISE). WISE provides wheel profile and dimensional measurements, i.e. rim thickness, flange height, flange ...

  19. Information-Driven Inspections

    International Nuclear Information System (INIS)

    Laughter, Mark D.; Whitaker, J. Michael; Lockwood, Dunbar

    2010-01-01

    New uranium enrichment capacity is being built worldwide in response to perceived shortfalls in future supply. To meet increasing safeguards responsibilities with limited resources, the nonproliferation community is exploring next-generation concepts to increase the effectiveness and efficiency of safeguards, such as advanced technologies to enable unattended monitoring of nuclear material. These include attribute measurement technologies, data authentication tools, and transmission and security methods. However, there are several conceptual issues with how such data would be used to improve the ability of a safeguards inspectorate such as the International Atomic Energy Agency (IAEA) to reach better safeguards conclusions regarding the activities of a State. The IAEA is pursuing the implementation of information-driven safeguards, whereby all available sources of information are used to make the application of safeguards more effective and efficient. Data from continuous, unattended monitoring systems can be used to optimize on-site inspection scheduling and activities at declared facilities, resulting in fewer, better inspections. Such information-driven inspections are the logical evolution of inspection planning - making use of all available information to enhance scheduled and randomized inspections. Data collection and analysis approaches for unattended monitoring systems can be designed to protect sensitive information while enabling information-driven inspections. A number of such inspections within a predetermined range could reduce inspection frequency while providing an equal or greater level of deterrence against illicit activity, all while meeting operator and technology holder requirements and reducing inspector and operator burden. Three options for using unattended monitoring data to determine an information-driven inspection schedule are to (1) send all unattended monitoring data off-site, which will require advances in data analysis techniques to

  20. Experience with the implementation of a risk-based ISI program and inspection qualification

    International Nuclear Information System (INIS)

    Chapman, O.J.V.

    1996-01-01

    Rolls Royce and Associates (RRA) are the Design Authority (DA) for Nuclear Steam Raising Plant (NSRP) used for the Royal Naval Nuclear Fleet. Over the past seven years RRA, with support from the Ministry of Defense, has developed and implemented a risk based in-service inspection (RBISI) strategy for the NSRP. Having used risk as a means of optimizing where to inspect, an inspection qualification (IQ) process has now been put in place to ensure that proposed inspections deliver the expected gains assumed. This qualification process follows very closely that currently being put forward by the European Network on Inspection Qualification (ENIQ)

  1. Estimation of inspection effort

    International Nuclear Information System (INIS)

    Mullen, M.F.; Wincek, M.A.

    1979-06-01

    An overview of IAEA inspection activities is presented, and the problem of evaluating the effectiveness of an inspection is discussed. Two models are described - an effort model and an effectiveness model. The effort model breaks the IAEA's inspection effort into components; the amount of effort required for each component is estimated; and the total effort is determined by summing the effort for each component. The effectiveness model quantifies the effectiveness of inspections in terms of probabilities of detection and quantities of material to be detected, if diverted over a specific period. The method is applied to a 200 metric ton per year low-enriched uranium fuel fabrication facility. A description of the model plant is presented, a safeguards approach is outlined, and sampling plans are calculated. The required inspection effort is estimated and the results are compared to IAEA estimates. Some other applications of the method are discussed briefly. Examples are presented which demonstrate how the method might be useful in formulating guidelines for inspection planning and in establishing technical criteria for safeguards implementation

  2. Packaging supplier inspection guide

    International Nuclear Information System (INIS)

    Stromberg, H.M.; Gregg, R.E.; Kido, C.; Boyle, C.D.

    1991-05-01

    This is document is a guide for conducting quality assurance inspections of transportations packaging suppliers, where suppliers are defined as designers, fabricators, distributors, users, or owners of transportation packaging. This document can be used during an inspection to determine regulatory compliance within the requirements of 10 Code of Federal Regulations, Part 71, Subpart H (10 CFR 71.101--71.135). The guidance described in this document provides a framework for an inspection. It provides the inspector with the flexibility to adapt the methods and concepts presented here to meet the needs of the particular facility being inspected. The guide was developed to ensure a structured and consistent approach for inspections. The method treats each activity at a supplier facility as a separate entity (or functional element), and combines the activities within the framework of an ''inspection tree.'' The method separates each functional element into several areas of performance and then identifies guidelines, based on regulatory requirements, to be used to qualitatively rate each area. This document was developed to serve as a field manual to facilitate the work of inspectors. 1 ref., 1 fig., 5 tabs

  3. Fuel inspection device

    International Nuclear Information System (INIS)

    Tsuji, Tadashi.

    1990-01-01

    The fuel inspection device of the present invention has a feature of obtaining an optimum illumination upon fuel rod interval inspection operation in a fuel pool. That is, an illumination main body used underwater is connected to a cable which is led out on a floor. A light control device is attached to the other end of the cable and an electric power cable is connected to the light control device. A light source (for example, incandescent lamp) is incorporated in the casing of the illumination main body, and a diffusion plate is disposed at the front to provide a plane light source. The light control device has a light control knob capable of remote-controlling the brightness of the light of the illumination main body. In the fuel inspection device thus constituted, halation is scarcely caused on the image screen upon inspection of fuels by a submerged type television camera to facilitate control upon inspection. Accordingly, efficiency of the fuel inspection can be improved to shorten the operation time. (I.S.)

  4. Issues, challenges, and approaches for risk-informed decommissioning in the United States

    International Nuclear Information System (INIS)

    Orlando, D.A.; Johnson, R.L.

    2005-01-01

    Full text: The U.S. Nuclear Regulatory Commission (US-NRC) is the principal Federal regulatory authority in the United States responsible for ensuring public health and safety from the civilian use of radioactive material. US-NRC staff has developed and implemented various risk-informed approaches for regulating and managing the remediation of contaminated sites. A risk-informed approach to regulating the decommissioning of nuclear facilities has been generally defined by the US-NRC staff as an approach to decision-making that uses risk insights as well as traditional considerations to focus regulator and licensee attention on decommissioning activities commensurate with their importance to health and safety. Ensuring that decommissioning is carried out using a risk-informed approach should improve the focus on safety in decommissioning, improve the effectiveness, efficiency, and realism in regulatory decisions, and reduce unnecessary regulatory burden, and cost, on licensees. This paper summarizes the efforts by the US-NRC to develop and implement risk-informed approaches to the remediation of nuclear facilities in the United States. It also discusses the issues and challenges encountered by the US-NRC in attempting to implement a risk-informed approach to decommissioning. The US-NRC has been incrementally implementing its existing risk-informed and performance-based approach as it has completed its decommissioning regulations, guidance and other tools over the past several years. The principal challenge for US-NRC is implementing the existing risk-informed approach at specific sites in a manner that maintains safety, reduces costs, and enhances public understanding of the US-NRC's approach. In addition, effectively communicating how the US-NRC approaches are risk-informed and performance-based; ensuring that licensees understand, and take advantage of, the flexibility in meeting the decommissioning goals; ensuring that licensees and staff are aware of the

  5. A quantitative approach for risk-informed safety significance categorization in option-2

    International Nuclear Information System (INIS)

    Ha, Jun Su; Seong, Poong Hyun

    2004-01-01

    OPTION-2 recommends that Structures, Systems, or Components (SSCs) of Nuclear Power Plants (NPPs) should be categorized into four groups according to their safety significance as well as whether they are safety-related or not. With changes to the scope of SSCs covered by 10 CFR 50, safety-related components which categorized into low safety significant SSC (RISC-3 SSC) can be exempted from the existing conservative burden (or requirements). As OPTION-2 paradigm is applied, a lot of SSCs may be categorized into RISC-3 SSCs. Changes in treatment of the RISC-3 SSCs will be recommended and then finally the recommended changes shall be evaluated. Consequently, before recommending the changes in treatment, probable candidate SSCs for the changes in treatment need to be identified for efficient risk-informed regulation and application (RIRA). Hence, in this work, a validation focused on the RISC-3 SSCs is proposed to identify probable candidate SSCs. Burden to Importance Ratio (BIR) is utilized as a quantitative measure for the validation. BIR is a measure representing the extent of resources or requirements imposed on a SSC with respect to the value of the importance measure of the SSC. Therefore SSCs having high BIR can be considered as probable candidate SSCs for the changes in treatment. In addition, the final decision whether RISC-3 SSCs can be considered as probable candidate SSCs or not should be made by an expert panel. For the effective decision making, a structured mathematical decision-making process is constructed based on Belief Networks (BBN) to overcome demerits of conventional group meeting based on unstructured discussion for decision-making. To demonstrate the usefulness of the proposed approach, the approach is applied to 22 components selected from 512 In-Service Test (IST) components of Ulchin unit 3. The results of the application show that the proposed approach can identify probable candidate SSCs for changes in treatment. The identification of the

  6. 10 CFR 50.69 - Risk-informed categorization and treatment of structures, systems and components for nuclear...

    Science.gov (United States)

    2010-01-01

    ..., systems and components for nuclear power reactors. (a) Definitions. Risk-Informed Safety Class (RISC)-1... functions. Risk-Informed Safety Class (RISC)-2 structures, systems and components (SSCs) means nonsafety-related SSCs that perform safety significant functions. Risk-Informed Safety Class (RISC)-3 structures...

  7. Incore inspection device

    International Nuclear Information System (INIS)

    Ogisu, Tatsuki; Taguchi, Kosei.

    1995-01-01

    The device of the present invention can inspect surfaces of equipments in reactor water in a nuclear reactor in a state of atmospheric air. Namely, an inspection device is movable forwardly and backwardly in a water-proof vessel. An annular sucker with pleats is disposed to the outer side of a lid of the water-proof vessel. A television camera for an under water monitoring is disposed to the inner side of the lid of the water-proof vessel by way of a partitioning wall with lid. Transferring screws are disposed at the back and on the side of the water-proof vessel. In the device having such a constitution, (1) the inside of the water-proof vessel is at first made water-tight by closing the partitioning wall with lid, (2) the back and the side screws are operated by the guide of the underwater monitoring television camera, to transfer the water-proof vessel to the surface of the reactor core to be inspected, (3) the annular sucker with pleats is urged on the surface to be inspected by the back screw, to fix the water-proof vessel, (4) reactor water in a space of the annular sucker with pleats is discharged and replaced with air, and (5) the lid of the partition wall with lid is opened and the inspection device is disposed at a position of the underwater monitoring television camera, to inspect the surface to be inspected in a state of atmospheric air. (I.S.)

  8. Evaluations of Structural Failure Probabilities and Candidate Inservice Inspection Programs

    Energy Technology Data Exchange (ETDEWEB)

    Khaleel, Mohammad A.; Simonen, Fredric A.

    2009-05-01

    The work described in this report applies probabilistic structural mechanics models to predict the reliability of nuclear pressure boundary components. These same models are then applied to evaluate the effectiveness of alternative programs for inservice inspection to reduce these failure probabilities. Results of the calculations support the development and implementation of risk-informed inservice inspection of piping and vessels. Studies have specifically addressed the potential benefits of ultrasonic inspections to reduce failure probabilities associated with fatigue crack growth and stress-corrosion cracking. Parametric calculations were performed with the computer code pc-PRAISE to generate an extensive set of plots to cover a wide range of pipe wall thicknesses, cyclic operating stresses, and inspection strategies. The studies have also addressed critical inputs to fracture mechanics calculations such as the parameters that characterize the number and sizes of fabrication flaws in piping welds. Other calculations quantify uncertainties associated with the inputs calculations, the uncertainties in the fracture mechanics models, and the uncertainties in the resulting calculated failure probabilities. A final set of calculations address the effects of flaw sizing errors on the effectiveness of inservice inspection programs.

  9. Inspection Strategies for Concrete Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    1989-01-01

    In this paper an optimal inspection strategy for concrete bridges based on periodic routine and detailed inspections is presented. The failure mode considered is corrosion of the reinforcement due to chlorides. A simple modelling of the corrosion and of the inspection strategy is presented....... The optimal inspection strategy is determined from an optimization problem, where the design variables are time intervals between detailed inspections and the concrete cover. The strategy is illustrated on a simple structure, namely a reinforced concrete beam....

  10. The nuclear industry's transition to risk-informed regulation and operation in the United States

    International Nuclear Information System (INIS)

    Kadak, Andrew C.; Matsuo, Toshihiro

    2007-01-01

    This paper summarizes a study of the transition of the United States nuclear industry from a prescriptive regulatory structure to a more risk informed approach to operations and regulations. The transition occurred over a 20 yr period in which gradual changes were made in the fundamental regulations and to the approach to nuclear safety and operations. While the number of actual regulatory changes were few, they are continuing. The utilities that embraced risk informed operations made dramatic changes in the way they approached operations and outage management. Those utilities that used risk in operations showed dramatic improvement in safety based on Institute of Nuclear Power Operations (INPO) performance indicators. It was also shown that the use of risk did not negatively affect safety performance of the plants compared to standard prescriptive approaches. This was despite having greater flexibility in compliance to regulatory standards and the use of the newly instituted risk-informed reactor oversight process. Key factors affecting the successful transition to a more risk-informed approach to regulations and operations are: strong top management support and leadership both at the regulator and the utility; education and training in risk principles and probabilistic risk Assessment tools for engineers, operators and maintenance staff; a slow and steady introduction of risk initiatives in areas that can show value to both the regulator and the industry; a transparent regulatory foundation built around a safety goal policy and the development of a strong safety culture at the utility to allow for more independence in safety compliance and risk management. The experience of the United States shows positive results in both safety and economics. The INPO and NRC metrics presented show that the use of risk information in operations and regulation is marginally better with no degradation in safety when plants that have embraced risk-informed approaches are compared

  11. Application of the risk-informed methodology for APR1400 P-T limits curve

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.; Namgung, I. [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2014-07-01

    A reactor pressure vessel (RPV) in a nuclear power plant has operational limits of pressure and temperature to prevent a potential drastic propagation of cracks due to brittle fracture. We call it a pressure-temperature limits curve (P-T limits curve). Appendix G of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section XI, provides deterministic procedures to develop the P-T limits curve for the reactor pressure vessel. Recently, an alternative risk-informed methodology has been added in the ASME Code. Risk-informed means that we can consider insights from a probabilistic risk assessment by using this methodology. This alternative methodology provides a simple procedure to develop risk-informed P-T limits for heat up, cool down, and hydrostatic test events. The risk-informed P-T limits curve is known to provide more operational flexibility, particularly for reactor pressure vessels with relatively high irradiation levels and radiation sensitive materials. In this paper, we developed both the deterministic and a risk-informed P-T limits curve for an APR1400 reactor using Appendix G of the ASME Code, Section XI and compare the results in terms of additional operational margin. (author)

  12. U.S. Nuclear Regulatory Commission Process for Risk-Informing the Nuclear Waste Arena

    International Nuclear Information System (INIS)

    Leslie, B. W.

    2003-01-01

    The U.S. Nuclear Regulatory Commission (NRC) is increasing the use of risk insights and information in its regulation of nuclear materials and waste. The objective of this risk-informed regulatory effort is to improve the effectiveness and efficiency of the agency, while maintaining or increasing its focus on safety. The agency's Office of Nuclear Material Safety and Safeguards (NMSS) proposed a five-step process to carry out a framework for increasing the use of risk information and insights in its regulation of nuclear materials and waste. The office is carrying out the five-step process to risk-inform the nuclear materials and waste arenas. NMSS's actions included forming a Risk Task Group and the use of case studies to test and complete screening criteria for identifying candidate regulatory applications amenable for risk-informing. Other actions included involving stakeholders through enhanced public participation, developing safety goals for materials and waste regulatory applications, and establishing a risk training program for staff. Through the case studies, NRC staff found the draft screening criteria to be effective in deciding regulatory areas that may be amenable to an increased use of risk insights. NRC staff also found that risk information may have the potential to reduce regulatory burden and improve staff's efficiency in making decisions, while maintaining safety. Finally, staff found that it would be possible to develop safety goals for the nuclear materials and waste arenas

  13. Proposed Regulatory Guideline on the PSA Quality for Risk-informed Applications

    International Nuclear Information System (INIS)

    Lee, Chang Ju; Choi, Jong Soo

    2005-01-01

    In the policy statement on nuclear safety issued by the Korean government in 1994, the introduction of risk-informed regulations in licensing and regulation of nuclear power plants was emphasized for the first time. It also describes the implementation of comprehensive safety assessment utilizing PSA (probabilistic safety assessment). Since then, because risk-informed environment and fundamentals had not been strong, several R and D on PSA and risk-informed regulation have been done even though their application has been delayed. However, today it is not the case. Since the follow-up policy statement (called Severe Accident Policy) was issued, which prescribes strong items such as PSA implementation and its periodic reassessment, reliability database, and risk monitoring program to the utility, we have a chance to easily get all kinds of risk information for improving current regulatory framework. In addition, with the overall availability of PSA results for all operating nuclear power plants, it is expected that many risk-informed applications (RIAs) will be submitted to the regulatory authority. In general, there are a lot of regulatory concerns associated with the quality assurance of licensee's submittals for RIA. It is also noted that making general requirements and touching specific check points are essential for the regulatory decision making process. This paper summarizes the structure and contents of our regulatory guideline for assuring PSA quality

  14. Mechanized inspection of steam generator components during manufacture

    International Nuclear Information System (INIS)

    Otte, H.-J.; Leupoldt, K.; Meister, W.

    2009-01-01

    Steam Generator (SG) parts are intensively inspected by UT in the course of the manufacturing process. These inspections - mostly performed manually using different codes - are time consuming and call for a sophisticated documentation, figuring part of the life time documentation package. In order to reduce time and costs mechanized inspection equipment is introduced, combining short inspection times, avoiding influence of the human factor and providing proper electronic storage of all inspection results prepared for comparison with data generated during in-service inspection. Since 2001 Cegelec delivered various UT systems for gas turbine disks and rotor ends called SIRO-MAN. Within only a few years the majority of important providers of such components successfully switched from manual inspection to mechanized inspection following the requirements of manufacturers like ALSTOM, GE and Siemens. The SIRO-MAN is now adapted to the needs of mechanized inspection of SG components. The inspection is performed on the products during rotation around the vertical axis. The multi - probe assemblies are manoeuvred on the products by a manipulator system backed by a NC control unit. Acoustic coupling of UT probes to the product surface is performed with oil or water in a closed circuit. UT and - if requested ET - data along with position information of the probe assembly provided by the control unit are acquired, processed and evaluated by an UT / ET electronic system delivered by either Olympus or ZETEC. As performed already on rotor ends a sequence of inspections using different parameter settings can be programmed with simple means (Teach In) so that such inspection sequence can be executed without operating personnel. Probe assemblies allow for individual operation of probes out of the probe assembly according to the individual needs. Conventional UT and phased array applications or combination of both techniques can be provided. The UT / ET electronic equipment offers

  15. Piping inspection round robin

    International Nuclear Information System (INIS)

    Heasler, P.G.; Doctor, S.R.

    1996-04-01

    The piping inspection round robin was conducted in 1981 at the Pacific Northwest National Laboratory (PNNL) to quantify the capability of ultrasonics for inservice inspection and to address some aspects of reliability for this type of nondestructive evaluation (NDE). The round robin measured the crack detection capabilities of seven field inspection teams who employed procedures that met or exceeded the 1977 edition through the 1978 addenda of the American Society of Mechanical Engineers (ASME) Section 11 Code requirements. Three different types of materials were employed in the study (cast stainless steel, clad ferritic, and wrought stainless steel), and two different types of flaws were implanted into the specimens (intergranular stress corrosion cracks (IGSCCs) and thermal fatigue cracks (TFCs)). When considering near-side inspection, far-side inspection, and false call rate, the overall performance was found to be best in clad ferritic, less effective in wrought stainless steel and the worst in cast stainless steel. Depth sizing performance showed little correlation with the true crack depths

  16. Inspection device in liquid

    International Nuclear Information System (INIS)

    Nagaoka, Etsuo.

    1996-01-01

    The present invention provides an inspection device in PWR reactor core in which inspection operations are made efficient by stabilizing a posture of the device in front-to-back, vertical and left-to-right directions by a simple structure. When the device conducts inspection while running in liquid, the front and the back directions of the device main body are inspected using a visual device while changing the posture by operating a front-to-back direction propulsion device and a right-to-left direction propulsion device, and a vertical direction propulsion device against to rolling, pitching and yawing of the device main body. In this case, a spherical magnet moves freely in the gravitational direction in a vibration-damping fluid in a non-magnetic spherical shell following the change of the posture of the device main body, in which the vibrations due to the movement of the spherical magnet is settled by the vibration-damping fluid thereby stabilizing the posture of the device main body. At a typical inspection posture, the settling effect is enhanced by the attraction force between the spherical magnets in the spherical shell and each of magnetic force-attracted magnetic members disposed to the outer circumference of the shell, and the posture of the device main body can be confirmed in front-to-back, right-to-left and vertical directions by each of the posture confirming magnetic sensors. (N.H.)

  17. Facilities for in-service control

    International Nuclear Information System (INIS)

    Werner, H.

    1980-01-01

    Up to now the efficiency of in-service control had been limited and dependent on special qualifications of the super-intending personnel and was thus neither exact nor transferable. In the meantime a great number of testing and measuring facilities for special application have been developed. Even novel types of testing methods do not grant absolutely precise statements. In most cases, however, there is a possibility of planning repairs by trend control and of avoiding failures of operation with aggravating consequences. Technical designers from all subject fields should be made familiar with the continually increasing spectrum of in-service inspection techniques so that a better application of modern and well-tried testing methods can be planned. Systematic in-service inspections complete the Rules of Technology which are safety-oriented with regard to the nonlinear wear between regular dates of control which has been ignored so far and its implied risks. Components which are not liable to control can be checked much better by novel type methods. (orig./RW) [de

  18. Plant abnormality inspection device

    International Nuclear Information System (INIS)

    Takenaka, Toshio.

    1990-01-01

    The present invention concerns a plant abnormality inspection device for conducting remote or automatic patrolling inspection in a plant and, more particularly, relates to such a device as capable of detecting abnormal odors. That is, the device comprises a moving device for moving to a predetermined position in the plant, a plurality of gas sensors for different kind of gases to be inspected mounted thereon, a comparator for comparing the concentration of a gas detected by the gas sensor with the normal gas concentration at the predetermined position and a judging means for judging the absence or presence of abnormality depending on the combination of the result of the comparison and deliverying a signal if the state is abnormal. As a result, a slight amount of gas responsible to odors released upon abnormality of the plant can be detected by a plurality of gas sensors for different kinds gases to rapidly and easily find abnormal portions in the plant. (I.S.)

  19. Magnetic particle inspection

    Science.gov (United States)

    Sastri, Sankar

    1990-01-01

    The purpose of this experiment is to familiarize the student with magnetic particle inspection and relate it to classification of various defects. Magnetic particle inspection is a method of detecting the presence of cracks, laps, tears, inclusions, and similar discontinuities in ferromagnetic materials such as iron and steel. This method will most clearly show defects that are perpendicular to the magnetic field. The Magnaglo method uses a liquid which is sprayed on the workpiece to be inspected, and the part is magnetized at the same time. The workpiece is then viewed under a black light, and the presence of discontinuity is shown by the formation of a bright indication formed by the magnetic particles over the discontinuity. The equipment and experimental procedures are described.

  20. A web environment for inspection service; Un entorno WEB para la inspeccion en servicio

    Energy Technology Data Exchange (ETDEWEB)

    Robles Guemes, N.; Garcia Heras, M.; Cueto-Felgueroso Garcia, C.; Pelaez Gutierrez, J. A.

    2013-07-01

    The in-service inspection fundamental objective is to maintain the structural integrity of structures, systems and components during the life in the installation service. Nuclear power plants are required to implement a Service inspection program in accordance with the established regulation by the Regulatory body.

  1. 33 CFR 150.518 - What are the inspection requirements for work vests and immersion suits?

    Science.gov (United States)

    2010-07-01

    ... requirements for work vests and immersion suits? 150.518 Section 150.518 Navigation and Navigable Waters COAST... vests and immersion suits? (a) All work vests and immersion suits must be inspected by the owner or... a work vest or immersion suit is inspected and is in serviceable condition, then it may remain in...

  2. Unique systems for inspection and repair of VVER steam generators

    International Nuclear Information System (INIS)

    Kovalyk, Adrian; Pilat, Peter; Jablonicky, Pavol

    2014-01-01

    During over 30 years, VUJE Trnava has developed a series of remote control manipulators for in-service inspection and maintenance of steam generator collectors. The manipulators have been widely used on WWER type reactors in Slovakia and abroad. Some of the manipulators for non-destructive testing are shown.

  3. Federal environmental inspections handbook

    International Nuclear Information System (INIS)

    1991-10-01

    This Federal Environmental Inspection Handbook has been prepared by the Department of Energy (DOE), Office of Environmental Guidance, RCRA/CERCLA Division (EH-231). It is designed to provide DOE personnel with an easily accessible compilation of the environmental inspection requirements under Federal environmental statutes which may impact DOE operations and activities. DOE personnel are reminded that this Handbook is intended to be used in concert with, and not as a substitute for, the Code of Federal Regulations (CFR). Federal Register (FR), and other applicable regulatory documents

  4. Subsea Infrastructure Inspection

    DEFF Research Database (Denmark)

    Mai, Christian; Pedersen, Simon; Hansen, Leif

    2016-01-01

    Due to the increasing energy demands, the offshore energy business has boomed in recent decades. Sub-sea pipeline and power transmission cable installations are commonly applied worldwide. Any potential breakages can cause equipment damage and also damage the environment. The majority...... (S-AUVs) can significantly change the inspections of infrastructure, as these vehicles could be much cheaper to deploy. S-AUVs can potentially conduct faster data collection and provide higher inspection data quality. However, there are still some technical challenges related to: underwater wireless...

  5. Inspection and test planning

    International Nuclear Information System (INIS)

    Miller, T.

    1980-01-01

    Purpose of Quality Plan - arrangement of all necessary tests or inspections as far as possible filted to certain components or systems. Subject of Quality Plan - precise determination of tests or inspections and - according to the actual safety significance - the certificates to be done. Disposition of Quality Plan - accommodation of tests to the actual state of fabrication. Application of Quality Plan - to any component or system that is regarded. Supervision of Employment - by authorized personnel of manufacturer, customer or authority providing exact employment of quality plan. Overservance of Instructions - certificates given by authorized personnel. (orig./RW)

  6. Study on effective provision of nuclear risk information over the internet

    International Nuclear Information System (INIS)

    Shobu, Nobuhiro

    2005-01-01

    'Risk information navigator (http://ricotti,jnc.go.jp/risknavi/)', an internet tool for arousing interest in risks and improving risk literacy, has been developed as the contents for the official website of Techno Community Square 'RICOTTI' (http://ricotti,jnc.go.jp/) at TOKAI village. This report discusses the effective provision of nuclear risk information toward foreigners who use English in Japan in order to improve their risk literacy. The contents are attached to this report with the CD-R media. (author)

  7. Treatment of Passive Component Reliability in Risk-Informed Safety Margin Characterization FY 2010 Report

    Energy Technology Data Exchange (ETDEWEB)

    Robert W Youngblood

    2010-09-01

    The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy (DOE) Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). A technical challenge at the core of this effort is to establish the conceptual and technical feasibility of analyzing safety margin in a risk-informed way, which, unlike conventionally defined deterministic margin analysis, is founded on probabilistic characterizations of SSC performance.

  8. Benefit and risk information in prescription drug advertising: review of empirical studies and marketing implications.

    Science.gov (United States)

    Kopp, S W; Bang, H K

    2000-01-01

    As pharmaceutical companies began to advertise prescription drugs directly to consumers as well as to physicians, understanding the impact of benefit and risk information in drug advertising on physicians and consumers has become more critical. This paper reviews previous empirical studies that examined the content of benefit and risk information in drug advertising and its potential effects on physicians' subsequent prescribing behaviors. It also reviews studies that investigated how consumers process information on a drug's efficacy and side effects. Based on the findings of these studies, implications are discussed for effective marketing information development as well as for government regulation.

  9. Research on the domestic application strategy of classification of SSCs with risk information

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seong Soo; Kim, Gi Yong; Seo, Jung Kwan [Atomic Creative Technology Co. Ltd., Daejeon (Korea, Republic of)

    2004-02-15

    In this study, US NRC's regulatory position for risk-informed SSC categorization was reviewed, and the methodology for risk-informed SSC categorization suggested by NEI was reviewed. The importance measure analysis for safety class pumps and valves in KSNP was performed and re-categorization of those pumps and valves was performed. The option 2 implementation experience of US utilities were collected and the cost-benefit analysis result was analyzed. Based on that, the cost-benefit analysis was tried for the case of option 2 implementation in Korea. Finally, the institutionalization method for Korea was suggested.

  10. Inspection of Emergency Arrangements

    International Nuclear Information System (INIS)

    2013-01-01

    The Working Group on Inspection Practices (WGIP) was tasked by the NEA CNRA to examine and evaluate the extent to which emergency arrangements are inspected and to identify areas of importance for the development of good inspection practices. WGIP members shared their approaches to the inspection of emergency arrangements by the use of questionnaires, which were developed from the requirements set out in IAEA Safety Standards. Detailed responses to the questionnaires from WGIP member countries have been compiled and are presented in the appendix to this report. The following commendable practices have been drawn from the completed questionnaires and views provided by WGIP members: - RBs and their Inspectors have sufficient knowledge and information regarding operator's arrangements for the preparedness and response to nuclear emergencies, to enable authoritative advice to be given to the national coordinating authority, where necessary. - Inspectors check that the operator's response to a nuclear emergency is adequately integrated with relevant response organisations. - Inspectors pay attention to consider the integration of the operator's response to safety and security threats. - The efficiency of international relations is checked in depth during some exercises (e.g. early warning, assistance and technical information), especially for near-border facilities that could lead to an emergency response abroad. - RB inspection programmes consider the adequacy of arrangements for emergency preparedness and response to multi-unit accidents. - RBs assess the adequacy of arrangements to respond to accidents in other countries. - The RB's role is adequately documented and communicated to all agencies taking part in the response to a nuclear or radiological emergency. - Inspectors check that threat assessments for NPPs have been undertaken in accordance with national requirements and that up-to-date assessments have been used as the basis for developing emergency plans for

  11. Optical surface contouring for non-destructive inspection of turbomachinery

    Science.gov (United States)

    Modarress, Dariush; Schaack, David F.

    1994-03-01

    Detection of stress cracks and other surface defects during maintenance and in-service inspection of propulsion system components, including turbine blades and combustion compartments, is presently performed visually. There is a need for a non-contact, miniaturized, and fully fieldable instrument that may be used as an automated inspection tool for inspection of aircraft engines. During this SBIR Phase 1 program, the feasibility of a ruggedized optical probe for automatic and nondestructive inspection of complex shaped objects will be established. Through a careful analysis of the measurement requirements, geometrical and optical constraints, and consideration of issues such as manufacturability, compactness, simplicity, and cost, one or more conceptual optical designs will be developed. The proposed concept will be further developed and a prototype will be fabricated during Phase 2.

  12. Pipework inspection apparatus

    International Nuclear Information System (INIS)

    Wrigglesworth, K.J.; Knowles, J.F.

    1987-01-01

    The patent concerns a pipework inspection apparatus, which is capable of negotiating bends in pipework. The apparatus comprises a TV camera system, which contains an optical section and an electronics section, which are connected by a flexible coupling. The system can be pulled or pushed along the bore of the pipework. (U.K.)

  13. Fuel assembly inspection device

    International Nuclear Information System (INIS)

    Yaginuma, Yoshitaka

    1998-01-01

    The present invention provides a device suitable to inspect appearance of fuel assemblies by photographing the appearance of fuel assemblies. Namely, the inspection device of the present invention measures bowing of fuel assembly or each of fuel rods or both of them based on the partially photographed images of fuel assembly. In this case, there is disposed a means which flashily projects images in the form of horizontal line from a direction intersecting obliquely relative to a horizontal cross section of the fuel assembly. A first image processing means separates the projected image pictures including projected images and calculates bowing. A second image processing means replaces the projected image pictures of the projected images based on projected images just before and after the photographing. Then, images for the measurement of bowing and images for inspection can be obtained simultaneously. As a result, the time required for the photographing can be shortened, the time for inspection can be shortened and an effect of preventing deterioration of photographing means by radiation rays can be provided. (I.S.)

  14. Overview and Demonstration of USEPA’s Risk-Informed Materials Management (RIMM) Tool System

    Science.gov (United States)

    The Risk-Informed Materials Management (RIMM) Tool System is a data gathering and analysis platform for conducting material disposal and beneficial use assessments. Users can evaluate risks to human and ecological receptors associated with exposures to organic and inorganic chemi...

  15. A framework of risk-informed seismic safety evaluation of nuclear power plants in Japan

    International Nuclear Information System (INIS)

    Kondo, S.; Sakagami, M.; Hirano, M.; Shiba, M.

    2001-01-01

    A framework of risk-informed seismic design and safety evaluation of nuclear power plants is under consideration in Japan so as to utilize the progress in the seismic probabilistic safety assessment methodology. Issues resolved to introduce this framework are discussed after the concept, evaluation process and characteristics of the framework are described. (author)

  16. Communicating Risk Information in Direct-to-Consumer Prescription Drug Television Ads: A Content Analysis.

    Science.gov (United States)

    Sullivan, Helen W; Aikin, Kathryn J; Poehlman, Jon

    2017-11-10

    Direct-to-consumer (DTC) television ads for prescription drugs are required to disclose the product's major risks in the audio or audio and visual parts of the presentation (sometimes referred to as the "major statement"). The objective of this content analysis was to determine how the major statement of risks is presented in DTC television ads, including what risk information is presented, how easy or difficult it is to understand the risk information, and the audio and visual characteristics of the major statement. We identified 68 DTC television ads for branded prescription drugs, which included a unique major statement and that aired between July 2012 and August 2014. We used subjective and objective measures to code 50 ads randomly selected from the main sample. Major statements often presented numerous risks, usually in order of severity, with no quantitative information about the risks' severity or prevalence. The major statements required a high school reading level, and many included long and complex sentences. The major statements were often accompanied by competing non-risk information in the visual images, presented with moderately fast-paced music, and read at a faster pace than benefit information. Overall, we discovered several ways in which the communication of risk information could be improved.

  17. Experiences gained in implementing a broad-based risk-informed application

    International Nuclear Information System (INIS)

    Schinzel, G.E.

    2004-01-01

    The South Texas Project was granted a first-of-kind exemption from special treatment requirements contained in 10-CFR Parts 21, 50, and 100 in August 2001. Since that time, South Texas has pursued a cautious, deliberate approach to implement these risk-informed exemption allowances. Over the past two years, South Texas has gained a unique insight into the challenges and benefits that exist in pursuing a broad-based risk-informed application. The American nuclear industry is currently pursuing similar capabilities through proposed rule 10-CFR 50.69 which is scheduled for NRC final review and approval in the July, 2004 time-frame. This proposed rule closely resembles the approach taken by South Texas in the exemption process and the allowances granted. For nuclear utilities that wish to pursue a similar broad-based risk-informed application, a well-conceived strategic approach is needed to prioritize the implementation activities as well as engage stake-holders in the implementation process. Cultural and communication challenges exist which must be addressed and effectively overcome. The goal of this paper is to communicate these challenges to the attendees, inform attendees of the safety and economic benefits to be recognized through this risk-informed approach, and to provide insight into continuing application opportunities that were not readily apparent when the broad-based exemption was originally conceived. This paper and presentation will be beneficial for both domestic and international attendees, as well as for personnel with utility or regulatory backgrounds. (author)

  18. Risk-informed approaches to assess ecological safety of facilities with radioactive waste

    International Nuclear Information System (INIS)

    Vashchenko, V.N.; Zlochevskij, V.V.; Skalozubov, V.I.

    2011-01-01

    Ingenious risk-informed methods to assess ecological safety of facilities with radioactive waste are proposed in the paper. Probabilistic norms on lethal outcomes and reliability of safety barriers are used as safety criteria. Based on the probability measures, it is established that ecological safety conditions are met for the standard criterion of lethal outcomes

  19. Analyses to support development of risk-informed separation distances for hydrogen codes and standards.

    Energy Technology Data Exchange (ETDEWEB)

    LaChance, Jeffrey L.; Houf, William G. (Sandia National Laboratories, Livermore, CA); Fluer, Inc., Paso Robels, CA; Fluer, Larry (Fluer, Inc., Paso Robels, CA); Middleton, Bobby

    2009-03-01

    The development of a set of safety codes and standards for hydrogen facilities is necessary to ensure they are designed and operated safely. To help ensure that a hydrogen facility meets an acceptable level of risk, code and standard development organizations are tilizing risk-informed concepts in developing hydrogen codes and standards.

  20. Proceedings of the NKS/SOS-2 seminar on risk informed principles

    International Nuclear Information System (INIS)

    Pulkkinen, U.; Simola, K.

    1999-09-01

    The aim of this NKS/SOS-2 seminar was to present the status and plans of applications of Risk Informed Principles both by nuclear authorities and industry in Finland and Sweden. Furthermore, views from the off-shore industry were presented. (EHS)

  1. Inspection of the Sizewll 'B' reactor coolant pump flywheels

    International Nuclear Information System (INIS)

    McNulty, A.L.; Cheshire, A.

    1992-01-01

    The Sizewell ''B'' safety case has categorised some primary circuit items as components for which failure is considered to be incredible. These Incredibility of Failure (IOF) components are particularly critical in their safety function, and specially stringent and all embracing provisions are made in their design, manufacture, inspection and operation. These provisions are such as to limit the probability of failure to levels which are so low that it does not have to be taken into account and no steps are necessary to control the consequences. The reactor coolant pump flywheel is considered to be an IOF component. Consequently there is a need for rigorous inspection during both manufacture and in service (ISI). The ISI requirement results in the need for an automated inspection. There is therefore a prerequisite to perform a Pre-Service Inspection (PSI) for baseline fingerprinting purposes. Furthermore there is a requirement that the inspection procedure, the inspection equipment and the operators are validated at the Inspection Validation Centre (IVC) of the AEA Technology laboratories at Risley. Development work is described. (author)

  2. Mobile X-ray inspection of light weight materials

    International Nuclear Information System (INIS)

    Ewert, Uwe; Redmer, Bernhard; Raedel, Christoph; Osterloh, Kurt; Schnars, Ulf; Henrich, Rudolf; Schimmelmann, Olaf; Bavendiek, Klaus; Jahn, Mirko

    2008-01-01

    Digital detectors such as phosphor imaging plates (IP) and digital detector arrays (DDA) allow radiographic inspection with higher efficiency and improved image quality in comparison to the classic film technique. Mobile X-ray flash tubes are used routinely for veterinarian and security applications. New high sensitive IPs and DDAs enable to apply them for inspection of light materials with low X-ray attenuation as in aluminium, plastics and composites. A versatile computed tomography (CT) system was developed for in situ inspection of large aircraft components under production conditions. A gate based planar computed tomograph was developed and tested for inspection of integrity of the stringer incorporation. Successful test trials were performed to prove the detection rate of cracks in embedded stringers. Honey comb structures of aircrafts have to be inspected for water inclusions during in-service inspections. Thermography is a powerful method for in house inspections when variations in temperature caused e.g. by sunshine can be excluded. A new X-ray diaphragm was developed for mobile back scatter measurements of large components. This method is insensitive to heat alterations in the field and thus can be applied also outdoors. (orig.)

  3. Adolescent perceptions of orthodontic treatment risks and risk information: A qualitative study.

    Science.gov (United States)

    Perry, John; Johnson, Ilona; Popat, Hashmat; Morgan, Maria Z; Gill, Paul

    2018-04-24

    For effective risk communication, clinicians must understand patients' values and beliefs in relation to the risks of treatment. This qualitative study aimed to explore adolescent perceptions of orthodontic treatment risks and risk information. Five focus groups were carried out with 32 school/college pupils aged 12-18 in Wales, UK. Participants were purposively selected and had all experienced orthodontic treatment. A thematic approach was used for analysis and data collection was completed at the point of data saturation. Four themes emerged from the data; (a) day-to-day risks of orthodontic treatment, (b) important orthodontic risk information, (c) engaging with orthodontic risk information and (d) managing the risks of orthodontic treatment. Day-to-day risks of orthodontic treatment that were affecting participants "here and now" were of most concern. Information about preventing the risks of treatment was deemed to be important. Participants did not actively seek risk information but engaged passively with information from convenient sources. Perceptions of risk susceptibility influenced participants' management of the risks of orthodontic treatment. This study demonstrates that adolescent patients can understand information about the nature and severity of orthodontic treatment risks. However, adolescent patients can have false perceptions if the risks are unfamiliar, perceived only to have a future impact or if seen as easy to control. Adolescent patients must be provided with timely and easily accessible risk information and with practical solutions to prevent the risks of treatment. The views and experiences gathered in this study can assist clinicians to better understand their young patients' beliefs about treatment risks, facilitate effective risk communication and contribute to improved patient-centred care. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Advanced inspection technology for non intrusive inspection (NII) program

    International Nuclear Information System (INIS)

    Zamir Mohamed Daud

    2003-01-01

    In the current economic environment, plants and facilities are under pressure to introduced cost saving as well as profit maximising measures. Among the many changes in the way things are run is a move towards Risk Based Inspection (RBI), with an emphasis on longer operating periods between shutdowns as well as to utilise components to their maximum capability. Underpinning and RBI program requires good data from an effective online inspections program, which would not require the shutdown of critical components. One methodology of online inspection is known as Non Intrusive Inspection (NII), an inspection philosophy with the objective of replacing internal inspection of a vessel by doing Non Destructive Testing (NDT) and inspections externally. To this end, a variety of advanced NDT techniques are needed to provide accurate online measurements. (Author)

  5. Overview of the software inspection process

    Energy Technology Data Exchange (ETDEWEB)

    Lane, G.L.; Dabbs, R. [Sandia National Labs., Albuquerque, NM (United States)

    1997-11-01

    This tutorial introduces attendees to the Inspection Process and teaches them how to organize and participate in a software inspection. The tutorial advocates the benefits of inspections and encourages attendees to socialize the inspection process in their organizations.

  6. Waste Inspection Tomography (WIT)

    International Nuclear Information System (INIS)

    Bernardi, R.T.

    1995-01-01

    Waste Inspection Tomography (WIT) provides mobile semi-trailer mounted nondestructive examination (NDE) and assay (NDA) for nuclear waste drum characterization. WIT uses various computed tomography (CT) methods for both NDE and NDA of nuclear waste drums. Low level waste (LLW), transuranic (TRU), and mixed radioactive waste can be inspected and characterized without opening the drums. With externally transmitted x-ray NDE techniques, WIT has the ability to identify high density waste materials like heavy metals, define drum contents in two- and three-dimensional space, quantify free liquid volumes through density and x-ray attenuation coefficient discrimination, and measure drum wall thickness. With waste emitting gamma-ray NDA techniques, WIT can locate gamma emitting radioactive sources in two- and three-dimensional space, identify gamma emitting isotopic species, identify the external activity levels of emitting gamma-ray sources, correct for waste matrix attenuation, provide internal activity approximations, and provide the data needed for waste classification as LLW or TRU. The mobile feature of WIT allows inspection technologies to be brought to the nuclear waste drum storage site without the need to relocate drums for safe, rapid, and cost-effective characterization of regulated nuclear waste. The combination of these WIT characterization modalities provides the inspector with an unprecedented ability to non-invasively characterize the regulated contents of waste drums as large as 110 gallons, weighing up to 1,600 pounds. Any objects that fit within these size and weight restrictions can also be inspected on WIT, such as smaller waste bags and drums that are five and thirty-five gallons

  7. Recurrent inspection of tubes

    International Nuclear Information System (INIS)

    Andersson, S.

    1984-01-01

    Recommendations concerning the selection of areas for the inspection of tubes have been outlined. The aim is to focus the control on the regions which are important for the safety and where damage is supposed to take place. The number of zones will depend on the risk factors as judged by experts. The localizing will be based upon probable damaging mechanisms. A certain number of areas should be chosen at random. (G.B.)

  8. Regulatory inspection in Spain

    International Nuclear Information System (INIS)

    Alvarez de Buergo, L.

    1977-01-01

    The 1964 Act on Nuclear Energy lays down that the Junta de Energia Nuclear is responsible for assessing the hazards of and inspecting nuclear power plants as well as for the transport of nuclear fuel for these plants. The Junta de Energia Nuclear has a specialised service, the Nuclear Safety Department in charge of performing these duties. Experience acquired from work in this field is analysed in this paper. (NEA) [fr

  9. Infrared microscope inspection apparatus

    Science.gov (United States)

    Forman, Steven E.; Caunt, James W.

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface.

  10. OSE inspections: A different perspective

    International Nuclear Information System (INIS)

    Ware, J.H.

    1987-01-01

    The Office of Security Evaluation (OSE) is a staff activity of the Assistant Secretary for Defense Programs (ASDP) and is responsible for the conduct of an inspection and evaluation program. The OSE Inspection Division conducts assessments of the effectiveness of Department of Energy (DOE) Safeguards and Security policies and protection programs. The inspections are conducted by OSE Inspectors and Support Specialists. Prior to the author's participation in the inspection of the San Francisco Operations Office, a DOE Field Office employee had never played an active role in an OSE Inspection of another field office. This paper discloses his experience as an OSE Inspector

  11. Terahertz Radome Inspection

    Directory of Open Access Journals (Sweden)

    Fabian Friederich

    2018-01-01

    Full Text Available Radomes protecting sensitive radar, navigational, and communications equipment of, e.g., aircraft, are strongly exposed to the environment and have to withstand harsh weather conditions and potential impacts. Besides their significance to the structural integrity of the radomes, it is often crucial to optimize the composite structures for best possible radio performance. Hence, there exists a significant interest in non-destructive testing techniques, which can be used for defect inspection of radomes in field use as well as for quality inspection during the manufacturing process. Contactless millimeter-wave and terahertz imaging techniques provide millimeter resolution and have the potential to address both application scenarios. We report on our development of a three-dimensional (3D terahertz imaging system for radome inspection during industrial manufacturing processes. The system was designed for operation within a machining center for radome manufacturing. It simultaneously gathers terahertz depth information in adjacent frequency ranges, from 70 to 110 GHz and from 110 to 170 GHz by combining two frequency modulated continuous-wave terahertz sensing units into a single measurement device. Results from spiraliform image acquisition of a radome test sample demonstrate the successful integration of the measurement system.

  12. Status on system inspection and preventive maintenance of HANARO

    International Nuclear Information System (INIS)

    Kim, Young-Ki; Cho, Yeong-Garp; Kwag, Byung-Ho

    1999-01-01

    The HANARO is a 30 MW open pool type multi-purpose research reactor with forced light water coolant/moderator flows and heavy water annular reflector. The relatively small reactor core uses a low enriched fuel and is designed to maximize the power density, thus providing the required neutron flux for various research activities. It is mainly used for radioisotope production, nuclear material testing and neutron physics experiments. The initial criticality was achieved February 1995. Considering the importance of their functionality from the safety point of view, some components and equipment are categorized into a nuclear safety grade. There are three different inspection activities for the various reactor systems and components - a Surveillance Inspection(SI) for the safety grades and a Periodic Inspection (PI) for the non-safety grades and In-Service Inspection (ISI) for the ASME Sec.III components. All of the SIs are specified and required by the safety analysis report. The SI also differs from the PI in such a point that all kinds of activities for the SIs should be accompanied by an appropriate quality assurance, while for the PIs it is not necessarily mandatory. In addition, the inspection results for the SIs should go through an examination from regulatory body every two years and specific functions of the critical components or systems are demonstrated under the witness by the governmental inspector. The ISI is required and carried out as per international codes and standards as well as Korean atomic energy regulations. There are 54 SIs, 25 PIs and 4 ISIs for the HANARO. This paper concentrates on the managing strategy and its practices for the SIs and ISIs of the safety-related components, currently being done at HANARO. Most parts of the inspections fall into a group for the periodic performance testing and/or equipment calibration. Some mechanical inspections like a torque measurement are grouped into a preventive maintenance. Lastly the ASME Sec

  13. Pressurized water reactor inspection procedures

    International Nuclear Information System (INIS)

    Heinrich, D.; Mueller, G.; Otte, H.J.; Roth, W.

    1998-01-01

    Inspections of the reactor pressure vessels of pressurized water reactors (PWR) so far used to be carried out with different central mast manipulators. For technical reasons, parallel inspections of two manipulators alongside work on the refueling cavity, so as to reduce the time spent on the critical path in a revision outage, are not possible. Efforts made to minimize the inspection time required with one manipulator have been successful, but their effects are limited. Major reductions in inspection time can be achieved only if inspections are run with two manipulators in parallel. The decentralized manipulator built by GEC Alsthom Energie and so far emmployed in boiling water reactors in the USA, Spain, Switzerland and Japan allows two systems to be used in parallel, thus reducing the time required for standard inspection of a pressure vessel from some six days to three days. These savings of approximately three days are made possible without any compromises in terms of positioning by rail-bound systems. During inspection, the reactor refueling cavity is available for other revision work without any restrictions. The manipulator can be used equally well for inspecting standard PWR, PWR with a thermal shield, for inspecting the land between in-core instrumentation nozzles, BWR with and without jet pumps (complementary inspection), and for inspecting core support shrouds. (orig.) [de

  14. Risk monitor riskangel for risk-informed applications in nuclear power plants

    International Nuclear Information System (INIS)

    Wang, Fang; Wang, Jiaqun; Wang, Jin; Li, Yazhou; Hu, Liqin; Wu, Yican

    2016-01-01

    Highlights: • A general risk monitor riskangel with high-speed cutsets generator engine. • Benchmarks of actual nuclear power plant (NPP) instantaneous risk models. • Applications in daily operation, maintenance plan and component out of service. - Abstract: This paper studied the requirements of risk monitor software and its applications as a plant specific risk monitor, which supports risk-informed configuration risk management for the two CANDU 6 units at the Third Qinshan nuclear power plant (TQNPP) in China. It also describes the regulatory prospective on risk-informed Probabilistic Safety Assessment (PSA) applications and the use of risk monitor at operating nuclear power plants, high level technical and functional requirements for the development of CANDU specific risk monitor software, and future development trends.

  15. Using risk-informed asset management for feedwater system preventative maintenance optimization

    International Nuclear Information System (INIS)

    Kee, Ernest; Sun, Alice; Richards, Andrew; Grantom, Rick; Liming, James; Salter, James

    2004-01-01

    The initial development of a South Texas Project Nuclear Operating Company process for supporting preventative maintenance optimization by applying the Balance-Of-Plant model and Risk-Informed Asset Management alpha-level software applications is presented. Preventative maintenance activities are evaluated in the South Texas Project Risk-Informed Asset Management software while the plant maintains or improves upon high levels of nuclear safety. In the Balance-Of-Plant availability application, the level of detail in the feedwater system is enhanced to support plant decision-making at the component failure mode and human error mode level of indenture by elaborating on the current model at the super-component level of indenture. The enhanced model and modeling techniques are presented. Results of case studies in feedwater system preventative maintenance optimization sing plant-specific data are also presented. (author)

  16. Communicating genetic risk information for common disorders in the era of genomic medicine.

    Science.gov (United States)

    Lautenbach, Denise M; Christensen, Kurt D; Sparks, Jeffrey A; Green, Robert C

    2013-01-01

    Communicating genetic risk information in ways that maximize understanding and promote health is increasingly important given the rapidly expanding availability and capabilities of genomic technologies. A well-developed literature on risk communication in general provides guidance for best practices, including presentation of information in multiple formats, attention to framing effects, use of graphics, sensitivity to the way numbers are presented, parsimony of information, attentiveness to emotions, and interactivity as part of the communication process. Challenges to communicating genetic risk information include deciding how best to tailor it, streamlining the process, deciding what information to disclose, accepting that communications may have limited influence, and understanding the impact of context. Meeting these challenges has great potential for empowering individuals to adopt healthier lifestyles and improve public health, but will require multidisciplinary approaches and collaboration.

  17. Impediments for the application of risk-informed decision making in nuclear safety

    International Nuclear Information System (INIS)

    Hahn, L.

    2001-01-01

    A broad application of risk-informed decision making in the regulation of safety of nuclear power plants is hindered by the lack of quantitative risk and safety standards as well as of precise instruments to demonstrate an appropriate safety. An additional severe problem is associated with the difficulty to harmonize deterministic design requirements and probabilistic safety assessment. The problem is strengthened by the vulnerability of PSA for subjective influences and the potential of misuse. Beside this scepticism the nuclear community is encouraged to intensify the efforts to improve the quality standards for probabilistic safety assessments and their quality assurance. A prerequisite for reliable risk-informed decision making processes is also a well-defined and transparent relationship between deterministic and probabilistic safety approaches. (author)

  18. Why consumers behave as they do with respect to food safety and risk information

    DEFF Research Database (Denmark)

    Verbeke, Wim; Frewer, Lynn J.; Scholderer, Joachim

    2007-01-01

    rankings. The aim of this contribution is to provide a better understanding to food risk analysts of why consumers behave as they do with respect to food safety and risk information. This paper presents some cases of seemingly irrational and inconsistent consumer behaviour with respect to food safety...... and risk information and provides explanations for these behaviours based on the nature of the risk and individual psychological processes. Potential solutions for rebuilding consumer confidence in food safety and bridging between lay and expert opinions towards food risks are reviewed. These include......In recent years, it seems that consumers are generally uncertain about the safety and quality of their food and their risk perception differs substantially from that of experts. Hormone and veterinary drug residues in meat persist to occupy a high position in European consumers' food concern...

  19. Importance measures and genetic algorithms for designing a risk-informed optimally balanced system

    International Nuclear Information System (INIS)

    Zio, Enrico; Podofillini, Luca

    2007-01-01

    This paper deals with the use of importance measures for the risk-informed optimization of system design and management. An optimization approach is presented in which the information provided by the importance measures is incorporated in the formulation of a multi-objective optimization problem to drive the design towards a solution which, besides being optimal from the points of view of economics and safety, is also 'balanced' in the sense that all components have similar importance values. The approach allows identifying design systems without bottlenecks or unnecessarily high-performing components and with test/maintenance activities calibrated according to the components' importance ranking. The approach is tested at first against a multi-state system design optimization problem in which off-the-shelf components have to be properly allocated. Then, the more realistic problem of risk-informed optimization of the technical specifications of a safety system of a nuclear power plant is addressed

  20. Disclosure and rationality: comparative risk information and decision-making about prevention.

    Science.gov (United States)

    Schwartz, Peter H

    2009-01-01

    With the growing focus on prevention in medicine, studies of how to describe risk have become increasing important. Recently, some researchers have argued against giving patients "comparative risk information," such as data about whether their baseline risk of developing a particular disease is above or below average. The concern is that giving patients this information will interfere with their consideration of more relevant data, such as the specific chance of getting the disease (the "personal risk"), the risk reduction the treatment provides, and any possible side effects. I explore this view and the theories of rationality that ground it, and I argue instead that comparative risk information can play a positive role in decision-making. The criticism of disclosing this sort of information to patients, I conclude, rests on a mistakenly narrow account of the goals of prevention and the nature of rational choice in medicine.

  1. Risk informed approach and its application in Daya Bay NPP operation safety management

    International Nuclear Information System (INIS)

    He Yu; Zhang Jinlong; Bao Yukun

    2004-01-01

    The paper presents a systematic risk assessment approach based on probabilistic theory, and discusses its significance and application process in safety management. Risk informed approach that uses deterministic engineering principles and probabilistic methods is the appropriate approach to decision making at nuclear power plants. The paper also studies an actual case taken place at Daya Bay Nuclear Power Station using PSA approach to equipment maintenance. (authors)

  2. Key attributes of the SAPHIRE risk and reliability analysis software for risk-informed probabilistic applications

    International Nuclear Information System (INIS)

    Smith, Curtis; Knudsen, James; Kvarfordt, Kellie; Wood, Ted

    2008-01-01

    The Idaho National Laboratory is a primary developer of probabilistic risk and reliability analysis (PRRA) tools, dating back over 35 years. Evolving from mainframe-based software, the current state-of-the-practice has led to the creation of the SAPHIRE software. Currently, agencies such as the Nuclear Regulatory Commission, the National Aeronautics and Aerospace Agency, the Department of Energy, and the Department of Defense use version 7 of the SAPHIRE software for many of their risk-informed activities. In order to better understand and appreciate the power of software as part of risk-informed applications, we need to recall that our current analysis methods and solution methods have built upon pioneering work done 30-40 years ago. We contrast this work with the current capabilities in the SAPHIRE analysis package. As part of this discussion, we provide information for both the typical features and special analysis capabilities, which are available. We also present the application and results typically found with state-of-the-practice PRRA models. By providing both a high-level and detailed look at the SAPHIRE software, we give a snapshot in time for the current use of software tools in a risk-informed decision arena

  3. Development of the severe accident risk information database management system SARD

    International Nuclear Information System (INIS)

    Ahn, Kwang Il; Kim, Dong Ha

    2003-01-01

    The main purpose of this report is to introduce essential features and functions of a severe accident risk information management system, SARD (Severe Accident Risk Database Management System) version 1.0, which has been developed in Korea Atomic Energy Research Institute, and database management and data retrieval procedures through the system. The present database management system has powerful capabilities that can store automatically and manage systematically the plant-specific severe accident analysis results for core damage sequences leading to severe accidents, and search intelligently the related severe accident risk information. For that purpose, the present database system mainly takes into account the plant-specific severe accident sequences obtained from the Level 2 Probabilistic Safety Assessments (PSAs), base case analysis results for various severe accident sequences (such as code responses and summary for key-event timings), and related sensitivity analysis results for key input parameters/models employed in the severe accident codes. Accordingly, the present database system can be effectively applied in supporting the Level 2 PSA of similar plants, for fast prediction and intelligent retrieval of the required severe accident risk information for the specific plant whose information was previously stored in the database system, and development of plant-specific severe accident management strategies

  4. A database system for the management of severe accident risk information, SARD

    International Nuclear Information System (INIS)

    Ahn, K. I.; Kim, D. H.

    2003-01-01

    The purpose of this paper is to introduce main features and functions of a PC Windows-based database management system, SARD, which has been developed at Korea Atomic Energy Research Institute for automatic management and search of the severe accident risk information. Main functions of the present database system are implemented by three closely related, but distinctive modules: (1) fixing of an initial environment for data storage and retrieval, (2) automatic loading and management of accident information, and (3) automatic search and retrieval of accident information. For this, the present database system manipulates various form of the plant-specific severe accident risk information, such as dominant severe accident sequences identified from the plant-specific Level 2 Probabilistic Safety Assessment (PSA) and accident sequence-specific information obtained from the representative severe accident codes (e.g., base case and sensitivity analysis results, and summary for key plant responses). The present database system makes it possible to implement fast prediction and intelligent retrieval of the required severe accident risk information for various accident sequences, and in turn it can be used for the support of the Level 2 PSA of similar plants and for the development of plant-specific severe accident management strategies

  5. Development of Risk Management Technology/Development of Risk-Informed Application Technology

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Joon Eon; Kim, K. Y.; Ahn, K. I.; Lee, Y. H.; Lim, H. G.; Jung, W. S.; Choi, S. Y.; Han, S. J.; Ha, J. J.; Hwang, M. J.; Park, S. Y.; Yoon, C

    2007-06-15

    This project aims at developing risk-informed application technologies to enhance the safety and economy of nuclear power plant altogether. For this, the Integrated Level 1 and 2 PSA model is developed. In addition, the fire and internal flooding PSA models are improved according to the PSA standard of U.S.A. To solve the issues of domestic PSA model, the best-estimate thermal hydraulic analyses are preformed for the ATWS and LSSB. In order to reduce the uncertainty of PSA, several new PSA technologies are developed: (1) more exact quantification of large fault tree, (2) importance measure including the effects of external PSA. As feasibility studies of Option 2 and 3, the class of 6 systems' SSC are re-classified based on the risk information and the sensitivity analyses is performed for the EDG starting time, respectively. It is also improved that the methodology to identify the vital area of NPP. The research results of this project can be used in the regulatory body and the industry projects for risk-informed applications.

  6. Risk-Informed Safety Assurance and Probabilistic Assessment of Mission-Critical Software-Intensive Systems

    Science.gov (United States)

    Guarro, Sergio B.

    2010-01-01

    This report validates and documents the detailed features and practical application of the framework for software intensive digital systems risk assessment and risk-informed safety assurance presented in the NASA PRA Procedures Guide for Managers and Practitioner. This framework, called herein the "Context-based Software Risk Model" (CSRM), enables the assessment of the contribution of software and software-intensive digital systems to overall system risk, in a manner which is entirely compatible and integrated with the format of a "standard" Probabilistic Risk Assessment (PRA), as currently documented and applied for NASA missions and applications. The CSRM also provides a risk-informed path and criteria for conducting organized and systematic digital system and software testing so that, within this risk-informed paradigm, the achievement of a quantitatively defined level of safety and mission success assurance may be targeted and demonstrated. The framework is based on the concept of context-dependent software risk scenarios and on the modeling of such scenarios via the use of traditional PRA techniques - i.e., event trees and fault trees - in combination with more advanced modeling devices such as the Dynamic Flowgraph Methodology (DFM) or other dynamic logic-modeling representations. The scenarios can be synthesized and quantified in a conditional logic and probabilistic formulation. The application of the CSRM method documented in this report refers to the MiniAERCam system designed and developed by the NASA Johnson Space Center.

  7. Proposal for an integrated risk informed decision making process for German regulators

    International Nuclear Information System (INIS)

    Einarsson, Svante; Wielenberg, Andreas

    2013-01-01

    Regulatory decisions for German nuclear power plants (NPP) have traditionally been based on deterministic safety analyses. However, the IRRS-Mission of IAEA in 2008 proposed, among others, in 'Suggestion 25' to develop a national policy 'on the use of risk insights in the regulatory framework and decision making'. Consequently, the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) launched a project with the goal of developing a proposal for a uniform federal approach on using risk information in decision making. To this end, the state of the application of probabilistic and risk informed methods has been investigated both on an international and a national level. On the international level, the concept of Integrated Risk Informed Decision Making (IRIDM) has been defined in INSAG-25. It is a structured process, in which all knowledge and requirements relevant to the issue in question are to be considered in a decision. Such knowledge and other requirements are e.g. deterministic and probabilistic safety analyses, regulatory requirements and other applicable findings (including cost-benefit analyses). The IRIDM concept according to INSAG-25 is the cornerstone of the proposal for a uniform federal German approach for IRIDM in the regulatory framework for nuclear installations in Germany. (orig.)

  8. Risk-informed regulation: handling uncertainty for a rational management of safety

    International Nuclear Information System (INIS)

    Zio, Enrico

    2008-01-01

    A risk-informed regulatory approach implies that risk insights be used as supplement of deterministic information for safety decision-making purposes. In this view, the use of risk assessment techniques is expected to lead to improved safety and a more rational allocation of the limited resources available. On the other hand, it is recognized that uncertainties affect both the deterministic safety analyses and the risk assessments. In order for the risk-informed decision making process to be effective, the adequate representation and treatment of such uncertainties is mandatory. In this paper, the risk-informed regulatory framework is considered under the focus of the uncertainty issue. Traditionally, probability theory has provided the language and mathematics for the representation and treatment of uncertainty. More recently, other mathematical structures have been introduced. In particular, the Dempster-Shafer theory of evidence is here illustrated as a generalized framework encompassing probability theory and possibility theory. The special case of probability theory is only addressed as term of comparison, given that it is a well known subject. On the other hand, the special case of possibility theory is amply illustrated. An example of the combination of probability and possibility for treating the uncertainty in the parameters of an event tree is illustrated

  9. Development of Risk Management Technology/Development of Risk-Informed Application Technology

    International Nuclear Information System (INIS)

    Yang, Joon Eon; Kim, K. Y.; Ahn, K. I.; Lee, Y. H.; Lim, H. G.; Jung, W. S.; Choi, S. Y.; Han, S. J.; Ha, J. J.; Hwang, M. J.; Park, S. Y.; Yoon, C.

    2007-06-01

    This project aims at developing risk-informed application technologies to enhance the safety and economy of nuclear power plant altogether. For this, the Integrated Level 1 and 2 PSA model is developed. In addition, the fire and internal flooding PSA models are improved according to the PSA standard of U.S.A. To solve the issues of domestic PSA model, the best-estimate thermal hydraulic analyses are preformed for the ATWS and LSSB. In order to reduce the uncertainty of PSA, several new PSA technologies are developed: (1) more exact quantification of large fault tree, (2) importance measure including the effects of external PSA. As feasibility studies of Option 2 and 3, the class of 6 systems' SSC are re-classified based on the risk information and the sensitivity analyses is performed for the EDG starting time, respectively. It is also improved that the methodology to identify the vital area of NPP. The research results of this project can be used in the regulatory body and the industry projects for risk-informed applications

  10. A database system for the management of severe accident risk information, SARD

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, K. I.; Kim, D. H. [KAERI, Taejon (Korea, Republic of)

    2003-10-01

    The purpose of this paper is to introduce main features and functions of a PC Windows-based database management system, SARD, which has been developed at Korea Atomic Energy Research Institute for automatic management and search of the severe accident risk information. Main functions of the present database system are implemented by three closely related, but distinctive modules: (1) fixing of an initial environment for data storage and retrieval, (2) automatic loading and management of accident information, and (3) automatic search and retrieval of accident information. For this, the present database system manipulates various form of the plant-specific severe accident risk information, such as dominant severe accident sequences identified from the plant-specific Level 2 Probabilistic Safety Assessment (PSA) and accident sequence-specific information obtained from the representative severe accident codes (e.g., base case and sensitivity analysis results, and summary for key plant responses). The present database system makes it possible to implement fast prediction and intelligent retrieval of the required severe accident risk information for various accident sequences, and in turn it can be used for the support of the Level 2 PSA of similar plants and for the development of plant-specific severe accident management strategies.

  11. Development of the severe accident risk information database management system SARD

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Kwang Il; Kim, Dong Ha

    2003-01-01

    The main purpose of this report is to introduce essential features and functions of a severe accident risk information management system, SARD (Severe Accident Risk Database Management System) version 1.0, which has been developed in Korea Atomic Energy Research Institute, and database management and data retrieval procedures through the system. The present database management system has powerful capabilities that can store automatically and manage systematically the plant-specific severe accident analysis results for core damage sequences leading to severe accidents, and search intelligently the related severe accident risk information. For that purpose, the present database system mainly takes into account the plant-specific severe accident sequences obtained from the Level 2 Probabilistic Safety Assessments (PSAs), base case analysis results for various severe accident sequences (such as code responses and summary for key-event timings), and related sensitivity analysis results for key input parameters/models employed in the severe accident codes. Accordingly, the present database system can be effectively applied in supporting the Level 2 PSA of similar plants, for fast prediction and intelligent retrieval of the required severe accident risk information for the specific plant whose information was previously stored in the database system, and development of plant-specific severe accident management strategies.

  12. Risk-Informed External Hazards Analysis for Seismic and Flooding Phenomena for a Generic PWR

    Energy Technology Data Exchange (ETDEWEB)

    Parisi, Carlo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Prescott, Steve [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ma, Zhegang [Idaho National Lab. (INL), Idaho Falls, ID (United States); Spears, Bob [Idaho National Lab. (INL), Idaho Falls, ID (United States); Szilard, Ronaldo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kosbab, Ben [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-07-26

    This report describes the activities performed during the FY2017 for the US-DOE Light Water Reactor Sustainability Risk-Informed Safety Margin Characterization (LWRS-RISMC), Industry Application #2. The scope of Industry Application #2 is to deliver a risk-informed external hazards safety analysis for a representative nuclear power plant. Following the advancements occurred during the previous FYs (toolkits identification, models development), FY2017 focused on: increasing the level of realism of the analysis; improving the tools and the coupling methodologies. In particular the following objectives were achieved: calculation of buildings pounding and their effects on components seismic fragility; development of a SAPHIRE code PRA models for 3-loops Westinghouse PWR; set-up of a methodology for performing static-dynamic PRA coupling between SAPHIRE and EMRALD codes; coupling RELAP5-3D/RAVEN for performing Best-Estimate Plus Uncertainty analysis and automatic limit surface search; and execute sample calculations for demonstrating the capabilities of the toolkit in performing a risk-informed external hazards safety analyses.

  13. SmartInspect: Smart Contract Inspection Technical Report

    OpenAIRE

    Bragagnolo , Santiago; Rocha , Henrique ,; Denker , Marcus; Ducasse , Stéphane

    2017-01-01

    Smart contracts are embedded procedures stored with the data they act upon. Debugging deployed Smart Contracts is a difficult task since once deployed, the code cannot be reexecuted and inspecting a simple attribute is not easily possible because data is encoded. In this technical report, we present SmartInspect to address the lack of inspectability of a deployed contract. Our solution analyses the contract state by using decompilation techniques and a mirror-based architecture to represent t...

  14. Shell Inspection History and Current CMM Inspection Efforts

    Energy Technology Data Exchange (ETDEWEB)

    Montano, Joshua Daniel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-26

    The following report provides a review of past and current CMM Shell Inspection efforts. Calibration of the Sheffield rotary contour gauge has expired and the primary inspector, Matthew Naranjo, has retired. Efforts within the Inspection team are transitioning from maintaining and training new inspectors on Sheffield to off-the-shelf CMM technology. Although inspection of a shell has many requirements, the scope of the data presented in this report focuses on the inner contour, outer contour, radial wall thickness and mass comparisons.

  15. Technical specifications review of nuclear power plants: a risk-informed evaluation

    International Nuclear Information System (INIS)

    Saldanha, Pedro Luiz da Cruz; Sousa, Anna Leticia; Frutuoso e Melo, Paulo Fernando Ferreira; Duarte, Juliana Pacheco

    2012-01-01

    The use of risk information by a regulatory body as part of an integrated decision making process addresses the way in which risk information is being used as part of an integrated process in making decisions about safety issues at nuclear plants – commonly referred to as risk-informed decision making. The risk-informed approach aims to integrate in a systematic manner quantitative and qualitative, deterministic and probabilistic safety considerations to obtain a balanced decision. Probabilistic Safety Assessment (PSA) is a methodology that can be applied to provide a structured analysis process to evaluate the frequency and consequences of accidents scenarios in nuclear power plants. Technical Specifications (TS) are specifications regarding the characteristics of nuclear power plants (variables, systems or components) of overriding importance to nuclear safety and radiation protection, which is an integral part of plant operation authorization. Limiting Conditions of Operation (LCO) are the minimum levels of performance or capacity or operating system components required for the safe operation of nuclear plants, as defined in technical specifications. The Maintenance Rule (MR) is a requirement established by the U. S. Nuclear Regulatory Commission (NRC) to check the effectiveness of maintenance carried out in nuclear plants, and plant configuration control. The control of plant configuration is necessary to verify the impact of the maintenance of a safety device out of service on plant safety. The Electric Power Research Institute (EPRI) has assessed the role of probabilistic safety analysis in the regulation of nuclear power plants with the following objectives: a) to provide utilities with an approach for developing and implementing nuclear power station risk-managed technical specification programs; and b) to complement and supplement existing successful configuration risk management applications such as MR. This paper focuses on the evaluation of EPRI

  16. Barriers in using cardiometabolic risk information among consumers with low health literacy.

    Science.gov (United States)

    Damman, Olga C; Bogaerts, Nina M M; van Dongen, Diana; Timmermans, Danielle R M

    2016-02-01

    To identify the barriers from the perspective of consumers with low health literacy in using risk information as provided in cardiometabolic risk assessments. A qualitative thematic approach using cognitive interviews was employed. We performed interviews with 23 people with low health literacy/health numeracy, who were recruited through (1) several organisations and snowball sampling and (2) an online access panel. Participants completed the risk test of the Dutch national cardiometabolic risk assessment and viewed the personalized information about their risk. They were asked to answer probing questions about different parts of the information. The qualitative data were analysed by identifying main themes related to barriers in using the information, using a descriptive thematic approach. The four main themes identified were as follows: (1) People did not fully accept the risk message, partly because numerical information had ambiguous meaning; (2) people lacked an adequate framework for understanding their risk; (3) the purpose and setting of the risk assessment was unclear; and (4) current information tells nothing new: A need for more specific risk information. The main barriers were that the current presentation seemed to provoke undervaluation of the risk number and that texts throughout the test, for example about cardiometabolic diseases, did not match people's existing knowledge, failing to provide an adequate framework for understanding cardiometabolic risk. Our findings have implications for the design of disease risk information, for example that alternative forms of communication should be explored that provide more intuitive meaning of the risk in terms of good versus bad. What is already known on this subject? Online disease risk assessments have become widely available internationally. People with low SES and health literacy tend to participate less in health screening. Risk information is difficult to understand, yet little research has been

  17. Safeguards management inspection procedures

    International Nuclear Information System (INIS)

    Barth, M.J.; Dunn, D.R.

    1984-08-01

    The objective of this inspection module is to independently assess the contributions of licensee management to overall safeguards systems performance. The inspector accomplishes this objective by comparing the licensee's safeguards management to both the 10 CFR, parts 70 and 73, requirements and to generally accepted management practices. The vehicle by which this comparison is to be made consists of assessment questions and key issues which point the inspector to areas of primary concern to the NRC and which raise additional issues for the purpose of exposing management ineffectiveness. Further insight into management effectiveness is obtained through those assessment questions specifically directed toward the licensee's safeguards system performance. If the quality of the safeguards is poor, then the inspector should strongly suspect that management's role is ineffective and should attempt to determine management's influence (or lack thereof) on the underlying safeguards deficiencies. (The converse is not necessarily true, however.) The assessment questions in essence provide an opportunity for the inspector to identify, to single out, and to probe further, questionable management practices. Specific issues, circumstances, and concerns which point to questionable or inappropriate practices should be explicitly identified and referenced against the CFR and the assessment questions. The inspection report should also explain why the inspector feels certain management practices are poor, counter to the CFR, and/or point to ineffecive management. Concurrent with documenting the inspection results, the inspector should provide recommendations for alleviating observed management practices that are detrimental to effective safeguards. The recommendations could include: specific changes in the practices of the licensee, followup procedures on the part of NRC, and proposed license changes

  18. Laser Safety Inspection Criteria

    International Nuclear Information System (INIS)

    Barat, K.

    2005-01-01

    A responsibility of the Laser Safety Officer (LSO) is to perform laser audits. The American National Standard Z136.1 Safe Use of Lasers references this requirement through several sections. One such reference is Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''. The composition, frequency and rigor of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms It is common for audit findings from one inspector or inspection to the next to vary even when reviewing the same material. How often has one heard a comment, ''well this area has been inspected several times over the years and no one ever said this or that was a problem before''. A great number of audit items, and therefore findings, are subjective because they are based on the experience and interest of the auditor to particular items on the checklist. Beam block usage, to one set of eyes might be completely adequate, while to another, inadequate. In order to provide consistency, the Laser Safety Office of the National Ignition Facility Directorate has established criteria for a number of items found on the typical laser safety audit form. The criteria are distributed to laser users. It serves two broad purposes; first, it gives the user an expectation of what will be reviewed by an auditor. Second, it is an opportunity to explain audit items to the laser user and thus the reasons for some of these items, such as labelling of beam blocks

  19. Verification of Remote Inspection Techniques for Reactor Internal Structures of Liquid Metal Reactor

    International Nuclear Information System (INIS)

    Joo, Young Sang; Lee, Jae Han

    2007-02-01

    The reactor internal structures and components of a liquid metal reactor (LMR) are submerged in hot sodium of reactor vessel. The division 3 of ASME code section XI specifies the visual inspection as major in-service inspection (ISI) methods of reactor internal structures and components. Reactor internals of LMR can not be visually examined due to opaque liquid sodium. The under-sodium viewing techniques using an ultrasonic wave should be applied for the visual inspection of reactor internals. Recently, an ultrasonic waveguide sensor with a strip plate has been developed for an application to the under-sodium inspection. In this study, visualization technique, ranging technique and monitoring technique have been suggested for the remote inspection of reactor internals by using the waveguide sensor. The feasibility of these remote inspection techniques using ultrasonic waveguide sensor has been evaluated by an experimental verification

  20. Results of calendar year 1995 Well Inspection and Maintenance Program Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    McMaster, B.W.

    1996-07-01

    This document is a compendium of results of the 1995 Monitor Well Inspection and Maintenance Program at the US Department of Energy's Oak Ridge Y-12 Plant. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the effective longevity of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant from August through December 1995

  1. Verification of Remote Inspection Techniques for Reactor Internal Structures of Liquid Metal Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Lee, Jae Han

    2007-02-15

    The reactor internal structures and components of a liquid metal reactor (LMR) are submerged in hot sodium of reactor vessel. The division 3 of ASME code section XI specifies the visual inspection as major in-service inspection (ISI) methods of reactor internal structures and components. Reactor internals of LMR can not be visually examined due to opaque liquid sodium. The under-sodium viewing techniques using an ultrasonic wave should be applied for the visual inspection of reactor internals. Recently, an ultrasonic waveguide sensor with a strip plate has been developed for an application to the under-sodium inspection. In this study, visualization technique, ranging technique and monitoring technique have been suggested for the remote inspection of reactor internals by using the waveguide sensor. The feasibility of these remote inspection techniques using ultrasonic waveguide sensor has been evaluated by an experimental verification.

  2. Acoustic inspection device

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Aaron A.; Burghard, Brion J.; Skorpik, James R.; Pappas, Richard A.; Mullen, O. Dennis; Samuel, Todd J.; Reid, Larry D.; Harris, Joe C.; Valencia, Juan D.; Smalley, Jonathan T.; Shepard, Chester L.; Taylor, Theodore T.

    2005-09-06

    An ultrasound inspection apparatus particularly adapted to examine containers (sealed or unsealed) containing a liquid or solid bulk material. The apparatus has an overall configuration of a hand held pistol with a front transducer contact surface that is positioned against a front wall of the container. An ultrasound pulse is transmitted from the apparatus to be reflected from a back wall of a container being investigated. The received echo pulse is converted to a digital waveform. The waveform is analyzed relative to temperature, travel distance of the pulse(s), and time of travel to ascertain characteristics of the liquid or other materials and to provide identification of the same.

  3. Inspection of internal tank welds using the ACFM inspection method

    International Nuclear Information System (INIS)

    Topp, D.A.; Lugg, M.C.

    2009-01-01

    The paper describes recent developments of the ACFM technique and describes several case studies where ACFM has been used to inspect the internal plate welds on large steel storage tanks in refineries. For weld inspection, conventional methods such as magnetic particle inspection or vacuum box testing are generally used. This paper presents comparisons of the results from ACFM with those from the conventional methods, from which conclusions are drawn as to the benefits this technique offers in terms of cost, time savings and inspection reliability. (author)

  4. INSPECT: a package of computer programs for planning safeguards inspections

    International Nuclear Information System (INIS)

    Wincek, M.A.; Mullen, M.F.

    1979-04-01

    As part of the U.S. program to provide technical assistance to the International Atomic Energy Agency, a package of computer programs was developed for use in planning safeguards inspections of various types of nuclear facilities. The INSPECT software package is a set of five interactive FORTRAN programs which can be used to calculate the variance components of the MUF (Material Unaccounted For) statistic, the variance components of the D (difference) statistic, attribute and variables sampling plans, a measure of the effectiveness of the inspection, and a measurement of the cost of implementing the inspection plan. This report describes the programs and explains how to use them

  5. Westinghouse Owners Group Risk-Informed Regulation Efforts: Options 2 and 3

    International Nuclear Information System (INIS)

    Brown, Jason A.; Osterrieder, Robert A.; Lutz, Robert J.; Dingler, Maurice; Ward, Lewis A.

    2002-01-01

    The U.S. Nuclear Regulatory Commission (NRC) has initiated efforts to incorporate risk-informed methods to redefine the scope of the existing 10 CFR 50 regulations (Option 2) and to change the technical requirements of the regulations (Option 3). The overall objectives of these efforts are to enhance plant safety, provide a framework for risk-informed regulations, add flexibility to plant operations, and reduce regulatory burden. The Westinghouse Owners Group (WOG) has a variety of active programs in the risk-informed area, including a program in the Option 2 and Option 3 areas. These two programs will be summarized including the benefits and the technical approach. The purpose of Option 2 is to make changes to the overall scope of structures, systems and components (SSCs) covered by 10 CFR 50 requiring special treatment by formulating new risk-informed safety classification categories that are linked to current definitions of safety-related and important-to-safety. This initiative would permit possible changes to the current special treatment requirements based on risk insights. The Nuclear Energy Institute (NEI) has developed an Option 2 implementation guideline (NEI 00-04 Draft Revision B). The WOG has initiated a program to validate the NEI guideline and to provide an initial cost-benefit assessment of the revised categorization and treatment under Option 2 via trial application to two systems at both Surry Unit 1 and Wolf Creek. The WOG Option 2 program includes consideration of all of the components in the selected systems, regardless of whether or not they are modeled in the respective plant probabilistic risk assessment (PRA) studies. As a result, quantitative risk measures are not available for many of the components being considered. In this case, the WOG program will provide valuable input to the NEI guideline. Additionally, the WOG program extends the use of both of the dominant methodologies for risk-informed ISI (RI-ISI) to address repair and

  6. Development of a Multi-Channel Ultrasonic Testing System for Automated Ultrasonic Pipe Inspection of Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Hee Jong; Cho, Chan Hee; Cho, Hyun Joon

    2009-01-01

    Currently almost all in-service-inspection techniques, applied in domestic nuclear power plants, are partial to field inspection technique. These kinds of techniques are related to managing nuclear power plants by the operation of foreign-produced inspection devices. There have been so many needs for development of native in-service-inspection device because there is no native diagnosis device for nuclear power plant inspection yet in Korea. In this research, we developed several core techniques to make an automated ultrasonic pipe inspection system for nuclear power plants. A high performance multi-channel ultrasonic pulser/receiver module, an A/D converter module and a digital main CPU module were developed and the performance of the developed modules was verified. The S/N ratio, noise level and signal acquisition performance of the developed modules showed proper level as we designed in the beginning.

  7. Endoscopic inspection of steam turbines

    International Nuclear Information System (INIS)

    Maliniemi, H.; Muukka, E.

    1990-01-01

    For over ten years, Imatran Voima Oy (IVO) has developed, complementary inspection methods for steam turbine condition monitoring, which can be applied both during operation and shutdown. One important method used periodically during outages is endoscopic inspection. The inspection is based on the method where the internal parts of the turbine is inspected through access borings with endoscope and where the magnified figures of the internal parts is seen on video screen. To improve inspection assurance, an image-processing based pattern recognition method for cracks has been developed for the endoscopic inspection of turbine blades. It is based on the deduction conditions derived from the crack shape. The computer gives an alarm of a crack detection and prints a simulated image of the crack, which is then checked manually

  8. Waste inspection tomography (WIT)

    Energy Technology Data Exchange (ETDEWEB)

    Bernardi, R.T. [Bio-Imaging Research, Inc., Lincolnshire, IL (United States)

    1995-10-01

    Waste Inspection Tomography (WIT) provides mobile semi-trailer mounted nondestructive examination (NDE) and assay (NDA) for nuclear waste drum characterization. WIT uses various computed tomography (CT) methods for both NDE and NDA of nuclear waste drums. Low level waste (LLW), transuranic (TRU), and mixed radioactive waste can be inspected and characterized without opening the drums. With externally transmitted x-ray NDE techniques, WIT has the ability to identify high density waste materials like heavy metals, define drum contents in two- and three-dimensional space, quantify free liquid volumes through density and x-ray attenuation coefficient discrimination, and measure drum wall thickness. With waste emitting gamma-ray NDA techniques, WIT can locate gamma emitting radioactive sources in two- and three-dimensional space, identify gamma emitting, isotopic species, identify the external activity levels of emitting gamma-ray sources, correct for waste matrix attenuation, provide internal activity approximations, and provide the data needed for waste classification as LLW or TRU.

  9. Waste inspection tomography (WIT)

    International Nuclear Information System (INIS)

    Bernardi, R.T.

    1995-01-01

    Waste Inspection Tomography (WIT) provides mobile semi-trailer mounted nondestructive examination (NDE) and assay (NDA) for nuclear waste drum characterization. WIT uses various computed tomography (CT) methods for both NDE and NDA of nuclear waste drums. Low level waste (LLW), transuranic (TRU), and mixed radioactive waste can be inspected and characterized without opening the drums. With externally transmitted x-ray NDE techniques, WIT has the ability to identify high density waste materials like heavy metals, define drum contents in two- and three-dimensional space, quantify free liquid volumes through density and x-ray attenuation coefficient discrimination, and measure drum wall thickness. With waste emitting gamma-ray NDA techniques, WIT can locate gamma emitting radioactive sources in two- and three-dimensional space, identify gamma emitting, isotopic species, identify the external activity levels of emitting gamma-ray sources, correct for waste matrix attenuation, provide internal activity approximations, and provide the data needed for waste classification as LLW or TRU

  10. Inspections - a cost effective approach

    International Nuclear Information System (INIS)

    Joseph, C.

    1981-01-01

    This paper describes a cost effective approach for inspections of Computerized Nuclear Materials Control and Accounting Systems (CNMCAS). Highlighted is the capability to conduct an inspection program via portable telephone terminals from off-site locations. The program can be applied to various materials management functions including materials control, quality assurance, and materials accounting. The system is designed to facilitate inspections by both external and internal groups

  11. Inspection system performance test procedure

    International Nuclear Information System (INIS)

    Jensen, C.E.

    1995-01-01

    This procedure establishes requirements to administer a performance demonstration test. The test is to demonstrate that the double-shell tank inspection system (DSTIS) supplied by the contractor performs in accordance with the WHC-S-4108, Double-Shell Tank Ultrasonic Inspection Performance Specification, Rev. 2-A, January, 1995. The inspection system is intended to provide ultrasonic (UT) and visual data to determine integrity of the Westinghouse Hanford Company (WHC) site underground waste tanks. The robotic inspection system consists of the following major sub-systems (modules) and components: Mobile control center; Deployment module; Cable management assembly; Robot mechanism; Ultrasonic testing system; Visual testing system; Pneumatic system; Electrical system; and Control system

  12. Experience on inspection at PFPF

    International Nuclear Information System (INIS)

    Aoki, I.; Yamamoto, Y.; Takahashi, Saburo; Ooshima, Hirofumi; Kuniyasu, Kazufusa.

    1993-01-01

    In order to reduce a personal radiation exposure, Plutonium Fuel Production Facility (PFPF) introduced an automated MOX fabrication technology. Safeguards system for the PFPF was designed and installed so as to be compatible with automated process operation as much as possible. Introduction of these system in PFPF made possible to do the inspection measurements with unattended mode and Near Real Time Material Accountancy (NRTA), consequently inspection has been carrying out effectively and efficiently. This paper describes the new Inspection activities as a comparison with old Inspection activities based on our experience. (author)

  13. PWR vessel inspection performance improvements

    International Nuclear Information System (INIS)

    Blair Fairbrother, D.; Bodson, Francis

    1998-01-01

    A compact robot for ultrasonic inspection of reactor vessels has been developed that reduces setup logistics and schedule time for mandatory code inspections. Rather than installing a large structure to access the entire weld inspection area from its flange attachment, the compact robot examines welds in overlapping patches from a suction cup anchor to the shell wall. The compact robot size allows two robots to be operated in the vessel simultaneously. This significantly reduces the time required to complete the inspection. Experience to date indicates that time for vessel examinations can be reduced to fewer than four days. (author)

  14. Exploring Modularity in Services

    DEFF Research Database (Denmark)

    Avlonitis, Viktor; Hsuan, Juliana

    2017-01-01

    the effects of modularity and integrality on a range of different analytical levels in service architectures. Taking a holistic approach, the authors synthesize and empirically deploy a framework comprised of the three most prevalent themes in modularity and service design literature: Offering (service...... insights on the mirroring hypothesis of modularity theory to services. Originality/value The paper provides a conceptualization of service architectures drawing on service design, modularity, and market relationships. The study enriches service design literature with elements from modularity theory...

  15. Assessing the value of risk: Perspectives on the role of risk information in decision making

    Energy Technology Data Exchange (ETDEWEB)

    Egan, M.; Smith, Graham; Maul, P. [QuantiSci Limited, Henley-on-Thames (United Kingdom)

    1999-12-01

    The authors of this paper profess no formal ethical or philosophical training from which to develop their position on Values in Decisions on Risk. However, as scientists with practical experience in carrying out a range of quantitative studies, we consider that we have some understanding of the strengths and weaknesses inherent in environmental risk assessment. Moreover, in attempting to use the results of such assessments, we have observed some of the ways in which quantitative risk information is used and abused. In this paper, therefore, we offer a practitioner's perspective that underlines the essential role of risk as a tool to inform and guide decisions, while at the same time emphasising the need for its proportionate use in a complex arena. We draw on experience that includes assessments for radioactive waste management and disposal, but also incorporates a range of assignments where assessment of the scale of potential environmental liabilities was a critical factor in decision making. We do not pretend to offer a resolution to the challenges laid before this Symposium, but seek to explore common themes and lessons learned regarding the role of risk information in goal-setting, performance monitoring and the overall decision process. Policy makers and regulators must act responsibly to protect confidence, not just the health of people and the environment. In doing this, to ignore risk information as a key component of strategic thinking is equally as disproportionate as making it the sole basis for decision making. There is a clear need to explain better the basis of, and motives behind, decisions - not only in terms of transparency in risk assessment but also to distinguish between the scientific and the socio-political component of the argument.

  16. Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report

    International Nuclear Information System (INIS)

    2000-01-01

    OAK B188 Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report. The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-formed approach for the design and regulation of nuclear power plants. This approach will include the development and/or confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRS) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go further by focusing on the design of new plants

  17. Assessing the value of risk: Perspectives on the role of risk information in decision making

    International Nuclear Information System (INIS)

    Egan, M.; Smith, Graham; Maul, P.

    1999-01-01

    The authors of this paper profess no formal ethical or philosophical training from which to develop their position on Values in Decisions on Risk. However, as scientists with practical experience in carrying out a range of quantitative studies, we consider that we have some understanding of the strengths and weaknesses inherent in environmental risk assessment. Moreover, in attempting to use the results of such assessments, we have observed some of the ways in which quantitative risk information is used and abused. In this paper, therefore, we offer a practitioner's perspective that underlines the essential role of risk as a tool to inform and guide decisions, while at the same time emphasising the need for its proportionate use in a complex arena. We draw on experience that includes assessments for radioactive waste management and disposal, but also incorporates a range of assignments where assessment of the scale of potential environmental liabilities was a critical factor in decision making. We do not pretend to offer a resolution to the challenges laid before this Symposium, but seek to explore common themes and lessons learned regarding the role of risk information in goal-setting, performance monitoring and the overall decision process. Policy makers and regulators must act responsibly to protect confidence, not just the health of people and the environment. In doing this, to ignore risk information as a key component of strategic thinking is equally as disproportionate as making it the sole basis for decision making. There is a clear need to explain better the basis of, and motives behind, decisions - not only in terms of transparency in risk assessment but also to distinguish between the scientific and the socio-political component of the argument

  18. Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-08-01

    OAK B188 Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report. The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-formed approach for the design and regulation of nuclear power plants. This approach will include the development and/or confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRS) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go further by focusing on the design of new plants.

  19. A risk-informed perspective on deterministic safety analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Wan, P.T.

    2009-01-01

    In this work, the deterministic safety analysis (DSA) approach to nuclear safety is examined from a risk-informed perspective. One objective of safety analysis of a nuclear power plant is to demonstrate via analysis that the risks to the public from events or accidents that are within the design basis of the power plant are within acceptable levels with a high degree of assurance. This nuclear safety analysis objective can be translated into two requirements on the risk estimates of design basis events or accidents: the nominal risk estimate to the public must be shown to be within acceptable levels, and the uncertainty in the risk estimates must be shown to be small on an absolute or relative basis. The DSA approach combined with the defense-in-depth (DID) principle is a simplified safety analysis approach that attempts to achieve the above safety analysis objective in the face of potentially large uncertainties in the risk estimates of a nuclear power plant by treating the various uncertainty contributors using a stylized conservative binary (yes-no) approach, and applying multiple overlapping physical barriers and defense levels to protect against the release of radioactivity from the reactor. It is shown that by focusing on the consequence aspect of risk, the previous two nuclear safety analysis requirements on risk can be satisfied with the DSA-DID approach to nuclear safety. It is also shown the use of multiple overlapping physical barriers and defense levels in the traditional DSA-DID approach to nuclear safety is risk-informed in the sense that it provides a consistently high level of confidence in the validity of the safety analysis results for various design basis events or accidents with a wide range of frequency of occurrence. It is hoped that by providing a linkage between the consequence analysis approach in DSA with a risk-informed perspective, greater understanding of the limitation and capability of the DSA approach is obtained. (author)

  20. Laser Safety Inspection Criteria

    International Nuclear Information System (INIS)

    Barat, K

    2005-01-01

    A responsibility of the Laser Safety Officer (LSO) is to perform laser safety audits. The American National Standard Z136.1 Safe use of Lasers references this requirement in several sections: (1) Section 1.3.2 LSO Specific Responsibilities states under Hazard Evaluation, ''The LSO shall be responsible for hazards evaluation of laser work areas''; (2) Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''; and (3) Appendix D, under Survey and Inspections, it states, ''the LSO will survey by inspection, as considered necessary, all areas where laser equipment is used''. Therefore, for facilities using Class 3B and or Class 4 lasers, audits for laser safety compliance are expected to be conducted. The composition, frequency and rigueur of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms. In many institutions, a sole Laser Safety Officer (LSO) or a number of Deputy LSO's perform these audits. For that matter, there are institutions that request users to perform a self-assessment audit. Many items on the common audit list and the associated findings are subjective because they are based on the experience and interest of the LSO or auditor in particular items on the checklist. Beam block usage is an example; to one set of eyes a particular arrangement might be completely adequate, while to another the installation may be inadequate. In order to provide more consistency, the National Ignition Facility Directorate at Lawrence Livermore National Laboratory (NIF-LLNL) has established criteria for a number of items found on the typical laser safety audit form. These criteria are distributed to laser users, and they serve two broad purposes: first, it gives the user an expectation of what will be reviewed by an auditor, and second, it is an

  1. Applicability of risk-informed criticality methodology to spent fuel repositories

    International Nuclear Information System (INIS)

    Mays, C.; Thomas, D.A.; Favet, D.

    2000-01-01

    An important objective of geologic disposal is keeping the fissionable material in a condition so that a self-sustaining nuclear chain reaction (criticality) is highly unlikely. This objective supports the overall performance objective of any repository, which is to protect the health and safety of the public by limiting radiological exposure. This paper describes a risk-informed, performance-based methodology, which combines deterministic and probabilistic approaches for evaluating the criticality potential of high-level waste and spent nuclear fuel after the repository is sealed and permanently closed (postclosure). (authors)

  2. An approach for risk informed safety culture assessment for Canadian nuclear power stations

    International Nuclear Information System (INIS)

    Nelson, W.R.

    2010-01-01

    One of the most important components of effective safety and risk management for nuclear power stations is a healthy safety culture. DNV has developed an approach for risk informed safety culture assessment that combines two complementary paradigms for safety and risk management: loss prevention - for preventing and intervening in accidents; and critical function management - for achieving safety and performance goals. Combining these two paradigms makes it possible to provide more robust systems for safety management and to support a healthy safety culture. This approach is being applied to safety culture assessment in partnership with a Canadian nuclear utility. (author)

  3. On the use of risk-informed regulation including organizational factors

    International Nuclear Information System (INIS)

    Gibelli, S.M.O.; Alvarenga, M.A.B.

    1998-01-01

    Risk-Informed Regulation (RIR) can be applied by using Probabilistic Safety Assessment (PSA) as a basic tool. Traditionally, PSA methodology encompasses the calculation of failure probabilities of Structures, Systems and Components (SSCs) and direct associated human errors. However, there are indirect causes related to human failures, associated with Organizational Factors, which are normally not included in fault trees, that may influence plant risk evaluation. This paper discusses on possible applications of RIR and on Organizational Factors. It also presents a classification of Angra-1 NPP unresolved issues, aiming a future inclusion of these factors into a PSA calculation. (author)

  4. Integrating risk management and safety culture in a framework for risk informed decision making

    International Nuclear Information System (INIS)

    Nelson, W.R.

    2009-01-01

    Operators and regulators of nuclear power plants agree on the importance of maintaining safety and controlling accident risks. Effective safety and risk management requires treatment of both technical and organizational components. Probabilistic Risk Assessment (PRA) provides tools for technical risk management. However, organizational factors are not treated in PRA, but are addressed using different approaches. To bring both components together, a framework of Risk Informed Decision Making (RIDM) is needed. The objective tree structure of the International Atomic Energy Agency (IAEA) is a promising approach to combine both elements. Effective collaboration involving regulatory and industry groups is needed to accomplish the integration. (author)

  5. A risk-informed framework for establishing a beyond design basis safety basis for external hazards

    Energy Technology Data Exchange (ETDEWEB)

    Amico, P. [Hughes Associates, Inc, Baltimore, MD (United States); Anoba, R. [Hughes Associates, Inc, Raleigh, NC (United States); Najafi, B. [Hughes Associates, Inc., Los Gatos, CA (United States)

    2014-07-01

    The events at Fukushima Daiichi taught us that meeting a deterministic design basis requirement for external hazards does not assure that the risk is low. As observed at the plant, the two primary reasons for this are failure cliffs above the design basis event and that combined hazard effects are not considered in design. Because the possible combinations of design basis exceedences and external hazard combinations are very large and complex, an approach focusing only on the most important ones is needed. For this reason, a risk informed approach is the most effective approach, which is discussed in this paper. (author)

  6. Risk-Informed SSCs Categorization: Elicitation Method of Expert's Opinion

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Mee Jeong; Yang, Joon Eon; Kim, Kil Yoo

    2005-01-15

    The regulations have been performing by deterministic way since nuclear power plants have been operating. However, some SSCs identified as safety-significance by deterministic way, were turned out to be low or non safety-significant and some SSCs identified as non-safety significance were turned out to be high safety-significant according to the results of PSA. Considering these risk insights, Regulatory Guide 1.174 and 10CFR50.69 were drawn up, and we can re-categorize the SSCs according to their safety significance. Therefore, a study and an interest about the risk-informed SSCs re-categorization and treatment has been continued. The objective of this regulatory initiative is to adjust the scope of equipment subject to special regulatory treatment to better focus licensee and regulatory attention and resources on equipment that has safety significance. Current most regulations define the plant equipment necessary to meet deterministic regulatory basis as 'safety-related.' This equipment is subject to special treatment regulations. Other plant equipment is categorized as 'non-safety related,' and is not subject to a select number of special treatment requirement or a subset of those requirement. However, risk information is not a magic tool making a decision but a supporting tool to categorize SSCs. This is because only small parts of a plant are modeled in PSA model. Thus, engineering and deterministic judgments are also used for risk-informed SSCs categorization, and expert opinion elicitation is very important for risk-informed SSCs categorization. Therefore, we need a rational method to elicit the expert's opinions, and in this study, we developed a systematic method for expert elicitation to categorize the nuclear power plants' SSCs. Current states for SSCs categorization of the USA and the existing methods for expert elicitation were surveyed and more systematic way eliciting the expert opinions and combining was developed. To

  7. Development of portal web site for fostering of risk literacy 'risk information navigator'

    International Nuclear Information System (INIS)

    Shobu, Nobuhiro; Mitsui, Seiichiro; Nakamura, Hirofumi

    2004-01-01

    Risk communication activities are important for promoting mutual understanding between local communities and Japan Nuclear Cycle Development Institutes (JNC). In addition to conventional public relation activities, the risk communication study team of JNC Tokai Works has started practical studies to promote further mutual understanding with its local communities. This paper reports the design and concept of a web site for the fostering of risk literacy, the 'Risk Information Navigator', that was developed as one of the risk communication methods, and surveys the web site from the user's perspective. (author)

  8. A Case Study of Risk Informed Asset Management (RIAM) for Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Gyoung Cheol; Jeong, Yong Hoon; Chang, Soon Heung; Chung, Dae Wook

    2006-01-01

    Recently, the concern for Nuclear Asset Management (NAM) is increasing in nuclear industry. Asset Management is management of the financial assets of a company in order to maximize return. However, asset management in the nuclear industry is needed for coincidental consideration of nuclear safety and risk. Over fast several years, efforts for development of safety concerned and financial asset maximizing method, process and tools have been continued internationally. Risk Informed Asset Management (RIAM) is a methodology, process, and (eventually) software tool by which analyst review historical performance and develop predictive logic models and data analyses to provide plant manager and company decision-makers critical quantitative performance indicators

  9. Short notice inspections

    International Nuclear Information System (INIS)

    Pouchkarev, V.

    1998-01-01

    For 30 years the IAEA safeguards system have evolved and have been strengthened by the regular introduction of new methods and techniques, improving both its effectiveness and efficiency. The member States of the IAEA have indicated their willingness to accept new obligations and associated technical measure that greatly strengthen the nuclear safeguards system. One element of this is the extent to which the IAEA inspectors have physical access to relevant locations for the purpose of providing independent verification of the exclusively peaceful intent of a State nuclear program. The Protocol to Safeguards granted new legal authority with respect to information on, and short notice inspector access to, all buildings on a nuclear site and administrative agreements that improve the process of designating inspectors and IAEA access to modern means of communication. This report is a short description of unannounced or short notice inspections as measures on which the new strengthened and cost efficient system will be based

  10. Inspection of disposal canisters components

    International Nuclear Information System (INIS)

    Pitkaenen, J.

    2013-12-01

    This report presents the inspection techniques of disposal canister components. Manufacturing methods and a description of the defects related to different manufacturing methods are described briefly. The defect types form a basis for the design of non-destructive testing because the defect types, which occur in the inspected components, affect to choice of inspection methods. The canister components are to nodular cast iron insert, steel lid, lid screw, metal gasket, copper tube with integrated or separate bottom, and copper lid. The inspection of copper material is challenging due to the anisotropic properties of the material and local changes in the grain size of the copper material. The cast iron insert has some acoustical material property variation (attenuation, velocity changes, scattering properties), which make the ultrasonic inspection demanding from calibration point of view. Mainly three different methods are used for inspection. Ultrasonic testing technique is used for inspection of volume, eddy current technique, for copper components only, and visual testing technique are used for inspection of the surface and near surface area

  11. MTR fuel inspection at CERCA

    International Nuclear Information System (INIS)

    Fanjas, Y.

    1992-01-01

    The stringent specifications for MTR fuel plates and fuel elements require various sophisticated inspection techniques. In particular, the development of low enriched silicide fuels made it necessary to adapt these techniques to high density plates. This paper presents the status of inspection technology at CERCA. (author)

  12. 1990 waste tank inspection program

    International Nuclear Information System (INIS)

    McNatt, F.G.

    1990-01-01

    Aqueous radioactive wastes from Savannah River Site separations processes are contained in large underground carbon steel tanks. Tank conditions are evaluated by inspection using periscopes, still photography, and video systems for visual imagery. Inspections made in 1990 are the subject of this report

  13. Computerized automated remote inspection system

    International Nuclear Information System (INIS)

    The automated inspection system utilizes a computer to control the location of the ultrasonic transducer, the actual inspection process, the display of the data, and the storage of the data on IBM magnetic tape. This automated inspection equipment provides two major advantages. First, it provides a cost savings, because of the reduced inspection time, made possible by the automation of the data acquisition, processing, and storage equipment. This reduced inspection time is also made possible by a computerized data evaluation aid which speeds data interpretation. In addition, the computer control of the transducer location drive allows the exact duplication of a previously located position or flaw. The second major advantage is that the use of automated inspection equipment also allows a higher-quality inspection, because of the automated data acquisition, processing, and storage. This storage of data, in accurate digital form on IBM magnetic tape, for example, facilitates retrieval for comparison with previous inspection data. The equipment provides a multiplicity of scan data which will provide statistical information on any questionable volume or flaw. An automatic alarm for location of all reportable flaws reduces the probability of operator error. This system has the ability to present data on a cathode ray tube as numerical information, a three-dimensional picture, or ''hard-copy'' sheet. One important advantage of this system is the ability to store large amounts of data in compact magnetic tape reels

  14. Technology Assessment of the Inspection Readiness Plan in Chemical Weapons Convention Challenge Inspections

    National Research Council Canada - National Science Library

    Woodley, Anthony

    1998-01-01

    ...) Challenge Inspections. The CWC is an intrusive inspection. The Challenge Inspection allows for a team of international inspectors to inspect on very short notice a naval facility suspected of violating the CWC...

  15. Process Improvement to the Inspection Readiness Plan in Chemical Weapons Convention Challenge Inspections

    National Research Council Canada - National Science Library

    Triplett, William

    1997-01-01

    ...) Challenge Inspection. The CWC is an intensive inspection. The Challenge Inspection allows for a team of international inspectors to inspect a naval facility suspected of violating the CWC on very short notice...

  16. Ultrasonic phased arrays for nondestructive inspection of forgings

    International Nuclear Information System (INIS)

    Wuestenberg, H.; Rotter, B.; Klanke, H.P.; Harbecke, D.

    1993-01-01

    Ultrasonic examinations on large forgings like rotor shafts for turbines or components for nuclear reactors are carried out at various manufacturing stages and during in-service inspections. During the manufacture, most of the inspections are carried out manually. Special in-service conditions, such as those at nuclear pressure vessels, have resulted in the development of mechanized scanning equipment. Ultrasonic probes have improved, and well-adapted sound fields and pulse shapes and based on special imaging procedures for the representation of the reportable reflectors have been applied. Since the geometry of many forgings requires the use of a multitude of angles for the inspections in-service and during manufacture, phased-array probes can be used successfully. The main advantages of the phased-array concept, e.g. the generation of a multitude of angles with the typical increase of redundancy in detection and quantitative evaluation and the possibility to produce pictures of defect situations, will be described in this contribution

  17. Results of calendar year 1994 monitor well inspection and maintenance program, Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    McMaster, B.W.; Jones, S.B.; Sitzler, J.L.

    1995-06-01

    This document is a compendium of results of the calendar year 1994 Monitor Well Inspection and Maintenance Program at the Department of Energy Y-12 Plant in Oak Ridge, Tennessee. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the life expectancy of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant during 1994. All inspections were conducted between April and December

  18. Results of calendar year 1994 monitor well inspection and maintenance program, Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    McMaster, B.W. [Univ. of Tennessee, Knoxville, TN (United States); Jones, S.B.; Sitzler, J.L. [Oak Ridge National Lab., TN (United States)

    1995-06-01

    This document is a compendium of results of the calendar year 1994 Monitor Well Inspection and Maintenance Program at the Department of Energy Y-12 Plant in Oak Ridge, Tennessee. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the life expectancy of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant during 1994. All inspections were conducted between April and December.

  19. International cooperation in production inspections

    International Nuclear Information System (INIS)

    Limousin, S.

    2009-01-01

    Nuclear pressure equipment, like the reactor pressure vessel or steam generators, are manufactured in many countries all around the world. As only few reactors were built in the 90's, most of the nuclear safety authorities have lost part of their know how in component manufacturing oversight. For these two reasons, vendor inspection is a key area for international cooperation. On the one hand, ASN has bilateral relationships with several countries (USA, Finland, China...) to fulfill specific purposes. On the other hand, ASN participates in international groups like the MDEP ( Multinational Design Evaluation Program). A MDEP working group dedicated to vendor inspection cooperation enables exchanges of informations (inspection program plan, inspection findings...) among the regulators. Join inspections are organized. International cooperation could lead in the long term to an harmonization of regulatory practices. (author)

  20. Development of infrastructure for the regulatory authority to implement risk-informed regulation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    It is important to assure the technical adequacy of probabilistic risk assessment (PRA) to implement risk-informed regulation of nuclear power plants (NPPs). JNES has been conducting various activities, such as development of PRA model, method, and data base, in order to assure the technical adequacy of PRA as development of the infrastructure for the regulatory authority to implement risk-informed regulation. In 2012, JNES updated the reliability data base used in PRA and improved PRA models to enhance the technical bases of PRA. In addition, JNES has been establishing the PRA model for fuel damage in the spent fuel storage pool in NPPs. As for improvement of PRA model for core damage in reactor, JNES conducted the study including feasibility of a simplified reliability model for digital I and C system developed by the digital I and C task group of OECD/NEA CSNI WGRISK by reproducing the sample calculation, and improvement of PRA models of individual NPPs in Japan. JNES is making effort to develop the procedures of internal fire PRA and internal flooding PRA. To improve the internal fire PRA, JNES is participating in OECD/NEA FIRE project to obtain the latest information and to validate and improve the fire propagation analysis codes and the parameters. JNES is establishing a method for analyzing internal influence due to flooding in NPPs, and this method is the base to develop the procedure of internal flooding PRA. (author)