Critical safety issues in the design of fusion machines

International Nuclear Information System (INIS)

Kramer, W.

1991-01-01

In the course of developing fusion machines both general safety considerations and safety assessments for the various components and systems of actual machines increase in number and become more and more coherent. This is particularly true for the NET/ITER projects where safety analysis plays an increasing role for the design of the machine. Since in a D/T tokamak the radiological hazards will be dominant basic radiological safety objectives are discussed. Critical safety issues as identified in particular by the NET/ITER community are reviewed. Subsequently, issues of major concern are considered both for normal operation and for conceivable accidents. The following accidents are considered to be crucial: Loss of cooling in plasma facing components, loss of vacuum, tritium system failure, and magnet system failure. To mitigate accident consequences a confinement concept based on passive features and multiple barriers including detritiation and filtering has to be applied. The reactor building as final barrier needs special attention to cope with both internal and external hazards. (orig.)

Assessment of basic safety issues

International Nuclear Information System (INIS)

Queniart, D.

1996-01-01

Work on the French-German common safety approach for future nuclear power plants continued in 1994 to allow for more detailed discussion of some major issues, taking into account the options provided by the industry for the EPR (European Pressurized water Reactor) project, as described in the document entitled 'Conceptual Safety Features Review File'. Seven meetings of a GPR/RSK advisory experts subgroup, six GPR/RSK plenary sessions and six meetings of the safety authorities (DFD) dealt with the following topics: design of the systems and use of probabilistic approaches, application of a 'break preclusion' approach to the main primary pipings, protection against external hazards (aircraft crashes, explosions, earthquakes), provisions with respect to accidents involving core melt and to containment design, radiological consequences of reference accidents and accidents involving core melt at low pressure. The important aspects of the joint policy are recalled in the presentation. The whole set of GPR/RSK recommendations were agreed by the French and German safety authorities during the DFD meetings of 1994 and early 1995. The utilities decided to begin the basic design phase in February, 1995. Work is now continuing to develop the common French-German approach for future nuclear power plants, in the same way as before. In 1995, this mainly covers the design of the containment and of the systems, but also new issues such as the protection against secondary side overpressurization, radiological protection of workers and radioactive wastes. (J.S.). 3 figs., 1 tab

Key issues on safety design basis selection and safety assessment

International Nuclear Information System (INIS)

An, S.; Togo, Y.

1976-01-01

In current fast reactor design in Japan, four design accident conditions and four design seismic conditions are adopted as the design base classifications. These are classified by the considerations on both likelihood of occurrence and the severeness of the consequences. There are several major problem areas in safety design consideration such as core accident problems which include fuel sodium interaction, fuel failure propagation and residual decay heat removal, and decay heat removal systems problems which is more or less the problem of selection of appropriate system and of assurance of high reliability of the system. In view of licensing, two kinds of accidents are postulated in evaluating the adequacy of a reactor site. The one is the ''major accident'' which is the accident to give most severe radiation hazard to the public from technical point of view. The other is the ''hypothetical accident'', induced public accident of which is severer than that of major accident. While the concept of the former is rather unique to Japanese licensing, the latter is almost equivalent to design base hypothetical accident of the US practice. In this paper, design bases selections, key safety issues and some of the licensing considerations in Japan are described

Evaluation on safety issues of SMART

International Nuclear Information System (INIS)

Kim, W. S.; Seol, K. W.; Yoon, Y. K.; Lee, J. H.

2001-01-01

Safety issues on the SMART were evaluated in the light of the compliance with the Ministerial Ordinance of Technical Requirements applying to Nuclear Installations, which was recently revised. Evaluation concludes that regulatory requirements associated with following items have to be developed as the licensing criteria for the SMART: (1) proving the safety of design or materials different form existing reactors; (2) coping with beyond design basis accidents; (3) rulemaking on the safety of reactor safeguard vessel ; (4) ensuring integrity of steam generator tubes; and (5) classifying equipment based on their safety significance. Appropriate actions including implementation of new requirements under development should be taken for safety issues such as diversity of reactivity control and in-service inspection of steam generator tubes that are not complied with the current Technical Requirements. Safety level of the SMART design will be evaluated further by the more detailed assessment according to the Technical Requirements, and additional safety issues will be identified and resolved, if it necessary

Safety climate and accidents at work

DEFF Research Database (Denmark)

Ajslev, Jeppe; Dastjerdi, Efat Lali; Dyreborg, Johnny

2017-01-01

Aim: Occupational safety climate is utilized as a way to measure the risk of accidents and injuries at work. This study investigates which factors are associated with safety climate and accidents at work. Methods: In the 2012 round of the Danish Work Environment and Health Study, 15,144 workers...... from the general working population of Denmark replied to questions about safety climate and accidents at work. Mutually adjusted logistic regression analyses determined the association between variables. Results: Within the last year, 5.7% had experienced an accident resulting in sickness absence....... The number of safety climate problems was progressively associated with the odds ratio (OR) for accidents. For one safety climate problem the OR for accidents was 2.01 (95% CI 1.67–2.42), for four or more safety climate problems the OR was 4.57 (95% CI 3.64–5.74). Young workers (18–24 years) had higher odds...

Draft pilot report - Approaches to the resolution of safety issues

International Nuclear Information System (INIS)

2006-01-01

The purpose of this report is to present in a concise form how some safety matters associated with currently operating light water reactors have been addressed. The issues discussed in this report are common to member countries with currently operating LWRs (PWR, BWR, VVER) and, as such, have wide interest in the nuclear safety community. Accordingly, this report can serve as a reference for researchers, regulations and others (e.g., industry) interested in understanding the approach and status of issues. This report should also be useful for knowledge transfer by documenting what has been done or is planned regarding selected safety matters and as a source for identifying reference material containing additional detail. The issues addressed in this report should not be viewed as questioning the safety of operating reactors, which have reached very high operational safety record, but rather as areas where uncertainty in knowledge exists, where safety assessment has been based on conservative assumptions, and where regulatory decisions need, or will need to be confirmed. Thus, the development of sound technical bases through continuing research will improve the current knowledge and allow for more realistic safety assessment. The safety issues discussed in this initial version of the report are: - design basis accident spectrum; - severe accident issues; - reactor pressure vessel integrity; - hydrogen control; - containment integrity; - accident management; - station blackout; - high burnup fuel; - power up-rates; - ECCS strainer clogging; - boron dilution. For each issue, the scope of the issue is defined, its status discussed and planned work or research described, including schedule. This pilot version of the report is limited to input from nine countries (Belgium, Czech Republic, Finland, France, Germany, Japan, Korea, Sweden and the U.S.). An overview of this information for each issue by country is provided in the table. This document does not contain a

ALWR severe accident issue resolution in support of updated emergency planning

International Nuclear Information System (INIS)

Additon, Stephen L.; Leaver, David E.; Sorrell, Steven W.; Theofanous, Theo G.

2004-01-01

. The severe accident risk characteristics of the ALWRs reflect an emphasis on accident prevention, which is quantified in the URD as a maximum permissible core damage frequency of less than one occurrence in 100,000 reactor years. For severe accident sequences of a frequency lower than this criterion, the URD safety policy requires provisions to arrest, mitigate, and contain the accident and, accordingly, opportunities to terminate a core melt sequence are provided whenever practical at every stage of core degradation. This includes design provisions to maximize the chances of success for reflooding the reactor by depressurizing the primary system, provisions to ensure retention of core debris in the reactor vessel by cooling the outside of the reactor vessel, and provisions for a more favorable geometry for core debris cooling in the reactor cavity in order to slow and then terminate a core-concrete interaction. For all risk-significant branches of the containment event tree, it must be demonstrated that early containment failure is avoided. This paper addresses the severe accident issue resolution tasks which were undertaken by the U.S. ALWR Program and ARSAP to ensure that the capability of passive ALWRs to arrest, mitigate and contain severe accidents would be sufficient to justify a significant change in the appropriate emergency planning requirements. The next section summarizes all of the issue resolution activities that will culminate in the issuance by the U.S. Nuclear Regulatory Commission (NRC) of a Final Safety Evaluation Report for the passive ALWR URD, scheduled for January 1994. The following section addresses more recent activities undertaken by ARSAP to enhance the issue resolution basis and to provide additional confirmatory evidence supporting the URD criteria. Included are the ongoing activities to establish a technical case, if possible, for in-vessel retention for the passive PWR and for the accommodation of ex-vessel steam explosions in the

Casebook on electric safety accidents

International Nuclear Information System (INIS)

1987-09-01

This book gives concentration on electric safety accidents in domestic and abroad, which introduces general electrical safety with property of electricity, safe equipment and maintenance and protection of electric shock. It lists the cases of accident caused of electricity in domestic like accident in power substation, utilization equipment, load system and another accident by electricity like death in electric shock another by electricity like death in electric shock in new building construction, the cases caused of electricity in abroad like damage in electric shock by high voltage electric transformer, electric shock in summer and earth fault accident by fault cooling tower.

Progress in Addressing DNFSB Recommendation 2002-1 Issues: Improving Accident Analysis Software Applications

International Nuclear Information System (INIS)

VINCENT, ANDREW

2005-01-01

Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 2002-1 (''Quality Assurance for Safety-Related Software'') identified a number of quality assurance issues on the use of software in Department of Energy (DOE) facilities for analyzing hazards, and designing and operating controls to prevent or mitigate potential accidents. Over the last year, DOE has begun several processes and programs as part of the Implementation Plan commitments, and in particular, has made significant progress in addressing several sets of issues particularly important in the application of software for performing hazard and accident analysis. The work discussed here demonstrates that through these actions, Software Quality Assurance (SQA) guidance and software tools are available that can be used to improve resulting safety analysis. Specifically, five of the primary actions corresponding to the commitments made in the Implementation Plan to Recommendation 2002-1 are identified and discussed in this paper. Included are the web-based DOE SQA Knowledge Portal and the Central Registry, guidance and gap analysis reports, electronic bulletin board and discussion forum, and a DOE safety software guide. These SQA products can benefit DOE safety contractors in the development of hazard and accident analysis by precluding inappropriate software applications and utilizing best practices when incorporating software results to safety basis documentation. The improvement actions discussed here mark a beginning to establishing stronger, standard-compliant programs, practices, and processes in SQA among safety software users, managers, and reviewers throughout the DOE Complex. Additional effort is needed, however, particularly in: (1) processes to add new software applications to the DOE Safety Software Toolbox; (2) improving the effectiveness of software issue communication; and (3) promoting a safety software quality assurance culture

Proposal strategy and policy on nuclear safety for no-more severe accidents

International Nuclear Information System (INIS)

2013-01-01

Following the outspoken advice saying 'scientists and engineers concerning with nuclear power promotion and safety should be responsible for clarifying how preventable or what measures should be needed to prevent severe accidents occurring at Fukushima Daiichi nuclear power plants (NPPs)', committee on prevention of severe accidents at NPPs was established by relevant nuclear scientists and engineers involved so as to discuss basic issues to be solved from scientific and technical viewpoints. Based on the review of 'defense in depth' concept and accident analysis at Fukushima nuclear accident, four major proposals and six supplements to be established were identified such as: (1) finding mechanism of beyond imagination events for natural disaster, terrorism, and internal events, (2) reform of comprehensive safety standards and guidelines with performance basis easy to reflect latest knowledge and technology as 'back-fitting', (3) severe accidents measures, their validation, and drilling on accident management to advance procedures and develop human resources, and (4) risk communications and public disclosure of information. This article described backgrounds of committee's proposals on nuclear safety for no-more severe accidents. (T. Tanaka)

Safety Culture and Issue in the Malaysian Manufacturing Sector

Directory of Open Access Journals (Sweden)

Ali Danish

2017-01-01

Full Text Available . This paper highlights the Safety culture and issue in the Malaysian Manufacturing Sector and emphasis the high occupational accidents due to lack of safety culture and non-compliance of the requirements of Occupational Safety and Health Act 1994. The aim of this study is to review the occupational accidents occurrence in the Malaysia workplace since 2012-2016. Malaysia aimed to reduce the occupational accidents, the results show by DOSH increase that Occupational Noise Induced Hearing Loss 83.7%, occupational musculoskeletal diseases, 4.4% and occupational lung diseases 2.3%. But the as per the record from DOSH that in last 5-Years, the increment in the fatal accidents by Average 26%, Permanent Disability by Average 71% and Non-Permanent Disability by 64 % are investigated only in Manufacturing Industries. The government must show their high interest on such a vulnerable employees to accomplish the above aim. This step will be helpful for planning to reduce the accidents in workplaces and it will also detect the prevention for the future accidents.

Commercial truck parking and other safety issues.

Science.gov (United States)

2015-10-01

Commercial truck parking is a safety issue, since trucks are involved in approximately 10% of all fatal accidents on interstates and : parkways in Kentucky. Drivers experience schedule demands and long hours on the road, yet they cannot easily determ...

[Implementation of safety devices: biological accident prevention].

Science.gov (United States)

Catalán Gómez, M Teresa; Sol Vidiella, Josep; Castellà Castellà, Manel; Castells Bo, Carolina; Losada Pla, Nuria; Espuny, Javier Lluís

2010-04-01

Accidental exposures to blood and biological material were the most frequent and potentially serious accidents in healthcare workers, reported in the Prevention of Occupational Risks Unit within 2002. Evaluate the biological percutaneous accidents decrease after a progressive introduction of safety devices. Biological accidents produced between 2.002 and 2.006 were analyzed and reported by the injured healthcare workers to the Level 2b Hospital Prevention of Occupational Risk Unit with 238 beds and 750 employees. The key of the study was the safety devices (peripheral i.v. catheter, needleless i.v. access device and capillary blood collection lancet). Within 2002, 54 percutaneous biological accidents were registered and 19 in 2006, that represents a 64.8% decreased. There has been no safety devices accident reported involving these material. Accidents registered during the implantation period occurred because safety devices were not used at that time. Safety devices have proven to be effective in reducing needle stick percutaneous accidents, so that they are a good choice in the primary prevention of biological accidents contact.

The role of quantitative uncertainty in the safety analysis of flammable gas accidents in Hanford waste tanks

International Nuclear Information System (INIS)

Bratzel, D.R.

1998-01-01

Following a 1990 investigation into flammable gas generation, retention, and release mechanisms within the Hanford Site high-level waste tanks, personnel concluded that the existing Authorization Basis documentation did not adequately evaluate flammable gas hazards. The US Department of Energy Headquarters subsequently declared the flammable gas hazard as an unresolved safety issue. Although work scope has been focused on resolution of the issue, it has yet to be resolved due to considerable uncertainty regarding essential technical parameters and associated risk. Resolution of the Flammable Gas Safety Issue will include the identification of a set of controls for the Authorization Basis for the tanks which will require a safety analysis of flammable gas accidents. A traditional nuclear facility safety analysis is based primarily on the analysis of a set of bounding accidents to represent the risks of the possible accidents and hazardous conditions at a facility. While this approach may provide some indication of the bounding consequences of accidents for facilities, it does not provide a satisfactory basis for identification of facility risk or safety controls when there is considerable uncertainty associated with accident phenomena and/or data as is the case with potential flammable gas accidents at the Hanford Site. This is due to the difficulties in identifying the bounding case and reaching consensus among safety analysts, facility operations and engineering, and the regulator on the implications of the safety analysis results. In addition, the bounding cases are frequently based on simplifying assumptions that make the analysis results insensitive to variations among facilities or the impact of alternative safety control strategies. The existing safety analysis of flammable gas accidents for the Tank Waste Remediation system (TWRS) at the Hanford Site has these difficulties. However, Hanford Site personnel are developing a refined safety analysis approach

Safety issues for superconducting fusion magnets

International Nuclear Information System (INIS)

Hsieh, S.Y.; Reich, M.; Powell, J.R.

1978-01-01

Safety issues for future superconducting fusion magnet systems are examined. It is found that safety and failure experience with existing superconducting magnets is not very applicable to predictions as to the safety and reliability of fusion magnets. Such predictions will have to depend on analysis and judgement for many years to come, rather than on accumulated experience. A number of generic potential structural, thermal-hydraulic, and electrical safety problems are identified and analyzed. Prevention of quenches and non-uniform temperature distributions, if quenches should occur, is of great importance, since such events can trigger processes which lead to magnet damage or failure. Engineered safety features will be necessary for fusion magnets. Two of these, an energy dispersion system and external coil containment, appear capable of reducing the probability of coil disruption to very low levels. However, they do not prevent loss of function accidents which are of economic concern. Elaborate detector, temperature equalization, and energy removal systems will be required to minimize the chances of loss of function accidents

On applying safety archetypes to the Fukushima accident to identify nonlinear influencing factors

Energy Technology Data Exchange (ETDEWEB)

Sousa, A.L., E-mail: alsousa@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Ribeiro, A.C.O., E-mail: antonio.ribeiro@bayer.com [Bayer Crop Science Brasil S.A., Belford Roxo, RJ (Brazil); Duarte, J.P., E-mail: julianapduarte@poli.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola Politecnica. Departamento de Engenharia Nuclear; Frutuoso e Melo, P.F., E-mail: frutuoso@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COOPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear

2013-07-01

Nuclear power plants are typically characterized as high reliable organizations. In other words, they are organizations defined as relatively error free over a long period of time. Another relevant characteristic of the nuclear industry is that safety efforts are credited to design. However, major accidents, like the Fukushima accident, have shown that new tools are needed to identify latent deficiencies and help improve their safety level. Safety archetypes proposed elsewhere (e. g., safety issues stalled in the face of technological advances and eroding safety) consonant with International Atomic Energy Agency (IAEA) efforts are used to examine different aspects of accidents in a systemic perspective of the interaction between individuals, technology and organizational factors. Safety archetypes can help consider nonlinear interactions. Effects are rarely proportional to causes and what happens locally in a system (near the current operating point) often does not apply to distant regions (other system states), so that one has to consider the so-called nonlinear interactions. This is the case, for instance, with human probability failure estimates and safety level identification. In this paper, we discuss the Fukushima accident in order to show how archetypes can highlight nonlinear interactions of factors that influenced it and how to maintain safety levels in order to prevent other accidents. The initial evaluation of the set of archetypes suggested in the literature showed that at least four of them are applicable to the Fukushima accident, as is inferred from official reports on the accident. These are: complacency (that is, the effects of complacency on safety), decreased safety awareness, fixing on symptoms and not the real causes and eroding safety. (author)

On applying safety archetypes to the Fukushima accident to identify nonlinear influencing factors

International Nuclear Information System (INIS)

Sousa, A.L.; Ribeiro, A.C.O.; Duarte, J.P.; Frutuoso e Melo, P.F.

2013-01-01

Nuclear power plants are typically characterized as high reliable organizations. In other words, they are organizations defined as relatively error free over a long period of time. Another relevant characteristic of the nuclear industry is that safety efforts are credited to design. However, major accidents, like the Fukushima accident, have shown that new tools are needed to identify latent deficiencies and help improve their safety level. Safety archetypes proposed elsewhere (e. g., safety issues stalled in the face of technological advances and eroding safety) consonant with International Atomic Energy Agency (IAEA) efforts are used to examine different aspects of accidents in a systemic perspective of the interaction between individuals, technology and organizational factors. Safety archetypes can help consider nonlinear interactions. Effects are rarely proportional to causes and what happens locally in a system (near the current operating point) often does not apply to distant regions (other system states), so that one has to consider the so-called nonlinear interactions. This is the case, for instance, with human probability failure estimates and safety level identification. In this paper, we discuss the Fukushima accident in order to show how archetypes can highlight nonlinear interactions of factors that influenced it and how to maintain safety levels in order to prevent other accidents. The initial evaluation of the set of archetypes suggested in the literature showed that at least four of them are applicable to the Fukushima accident, as is inferred from official reports on the accident. These are: complacency (that is, the effects of complacency on safety), decreased safety awareness, fixing on symptoms and not the real causes and eroding safety. (author)

Development of Draft Regulatory Guide on Accident Analysis for Nuclear Power Plants with New Safety Design Features

Energy Technology Data Exchange (ETDEWEB)

Bang, Young Seok; Woo, Sweng Woong; Hwang, Tae Suk [KINS, Daejeon (Korea, Republic of); Sim, Suk K; Hwang, Min Jeong [Environment and Energy Technology, Daejeon (Korea, Republic of)

2016-05-15

The present paper discusses the development process of the draft version of regulatory guide (DRG) on accident analysis of the NPP having the NSFD and its result. Based on the consideration on the lesson learned from the previous licensing review, a draft regulatory guide (DRG) on accident analysis for NPP with new safety design features (NSDF) was developed. New safety design features (NSDF) have been introduced to the new constructing nuclear power plants (NPP) since the early 2000 and the issuance of construction permit of SKN Units 3 and 4. Typical examples of the new safety features includes Fluidic Device (FD) within Safety Injection Tanks (SIT), Passive Auxiliary Feedwater System (PAFS), ECCS Core Barrel Duct (ECBD) which were adopted in APR1400 design and/or APR+ design to improve the safety margin of the plants for the postulated accidents of interest. Also several studies of new concept of the safety system such as Hybrid ECCS design have been reported. General and/or specific guideline of accident analysis considering the NSDF has been requested. Realistic evaluation of the impact of NSDF on accident with uncertainty and separated accident analysis accounting the NSDF impact were specified in the DRG. Per the developmental process, identification of key issues, demonstration of the DRG with specific accident with specific NSDF, and improvement of DGR for the key issues and their resolution will be conducted.

Road accident rates: strategies and programmes for improving road traffic safety.

Science.gov (United States)

Goniewicz, K; Goniewicz, M; Pawłowski, W; Fiedor, P

2016-08-01

Nowadays, the problem of road accident rates is one of the most important health and social policy issues concerning the countries in all continents. Each year, nearly 1.3 million people worldwide lose their life on roads, and 20-50 million sustain severe injuries, the majority of which require long-term treatment. The objective of the study was to identify the most frequent, constantly occurring causes of road accidents, as well as outline actions constituting a basis for the strategies and programmes aiming at improving traffic safety on local and global levels. Comparative analysis of literature concerning road safety was performed, confirming that although road accidents had a varied and frequently complex background, their causes have changed only to a small degree over the years. The causes include: lack of control and enforcement concerning implementation of traffic regulation (primarily driving at excessive speed, driving under the influence of alcohol, and not respecting the rights of other road users (mainly pedestrians and cyclists), lack of appropriate infrastructure and unroadworthy vehicles. The number of fatal accidents and severe injuries, resulting from road accidents, may be reduced through applying an integrated approach to safety on roads. The strategies and programmes for improving road traffic should include the following measures: reducing the risk of exposure to an accident, prevention of accidents, reduction in bodily injuries sustained in accidents, and reduction of the effects of injuries by improvement of post-accident medical care.

Severe accident issue resolution -- definition and perspective

International Nuclear Information System (INIS)

Harper, F.T.

1995-01-01

The purpose of this discussion is to introduce the session on the Progress on the Resolution of Severe Accident Issues. There has been much work in the area of resolution of severe accident issues over the past few years. This work has been focused on those issues most important to risk as assessed by comprehensive studies such as NUREG-1150. In particular, issues associated with early containment failure have been analyzed. These efforts to resolve issues have been hampered by the fact that open-quotes issue resolutionclose quotes has not always been well defined. The term open-quotes issue resolutionclose quotes conjures tip different images for the regulator, the accident analyst, the physicist, and the probabalist. In fact it is common to have as many different images of issue resolution as there are people in the room. This issue is complicated by the fact that the uncertainty in severe accident issues is enormous. (When convolved, the quantitative uncertainty in an integrated analysis due to severe accident issues can span several orders of magnitude.) In this summary, hierarchy is presented in an attempt to add some perspective to the resolution of issues in the face of large uncertainties. Recommendations are also made for analysts communicating in the area of issue resolution

Analysis on relation between safety input and accidents

Institute of Scientific and Technical Information of China (English)

YAO Qing-guo; ZHANG Xue-mu; LI Chun-hui

2007-01-01

The number of safety input directly determines the level of safety, and there exists dialectical and unified relations between safety input and accidents. Based on the field investigation and reliable data, this paper deeply studied the dialectical relationship between safety input and accidents, and acquired the conclusions. The security situation of the coal enterprises was related to the security input rate, being effected little by the security input scale, and build the relationship model between safety input and accidents on this basis, that is the accident model.

Unresolved safety issues: where do we go from here

International Nuclear Information System (INIS)

Aycock, M.B.

1980-01-01

Section 210 of the Energy reorganization Act of 1974, as amended requires the NRC to develop a program for resolving Unresolved Safety Issues related to nuclear power plants. Seventeen Unresolved Safety Issues were identified by the NRC in 1978 and by early 1979 the NRC Unresolved Safety Issues Program was quickly becoming a well defined and manageable effort. Although, the Three Mile Island accident caused the momentum developed in early 1979 to be lost, efforts on ongoing generic tasks were continued by a special NRC Task Force established in June 1979. The momentum that was lost must be regained, however, if the Congressional mandate in Section 210 is to be met. With increased industry involvement and the marriage of the Unresolved Safety Issues Program with the improved and broader safety program development, audit and evaluation activities of the new NRR Division of Safety Technology, this should be possible

Advances in operational safety and severe accident research

Energy Technology Data Exchange (ETDEWEB)

Simola, K. [VTT Automation (Finland)

2002-02-01

A project on reactor safety was carried out as a part of the NKS programme during 1999-2001. The objective of the project was to obtain a shared Nordic view of certain key safety issues related to the operating nuclear power plants in Finland and Sweden. The focus of the project was on selected central aspects of nuclear reactor safety that are of common interest for the Nordic nuclear authorities, utilities and research bodies. The project consisted of three sub-projects. One of them concentrated on the problems related to risk-informed deci- sion making, especially on the uncertainties and incompleteness of probabilistic safety assessments and their impact on the possibilities to use the PSA results in decision making. Another sub-project dealt with questions related to maintenance, such as human and organisational factors in maintenance and maintenance management. The focus of the third sub-project was on severe accidents. This sub-project concentrated on phenomenological studies of hydrogen combustion, formation of organic iodine, and core re-criticality due to molten core coolant interaction in the lower head of reactor vessel. Moreover, the current status of severe accident research and management was reviewed. (au)

Highlights from the literature on accident causation and system safety: Review of major ideas, recent contributions, and challenges

Energy Technology Data Exchange (ETDEWEB)

Saleh, J.H., E-mail: jsaleh@gatech.ed [School of Aerospace Engineering, Georgia Institute of Technology (United States); Marais, K.B. [School of Aeronautics and Astronautics, Purdue University (United States); Bakolas, E.; Cowlagi, R.V. [School of Aerospace Engineering, Georgia Institute of Technology (United States)

2010-11-15

: (1) that more fundamental research and cross-talk across several academic disciplines must be supported and incentivized for tackling the multi-disciplinary issues of accident causation and system safety (e.g., through the creation 'academic hubs' or 'centers of excellence' dedicated to system safety); and (2) that more interactions and partnerships between academia, industry, and government (especially accident investigation agencies) on accident causation and system safety issues would be particularly useful for all involved in advancing the safety agenda, from both research and education perspectives, and for disseminating research results, safety recommendations, and lessons learned from accident investigations.

Highlights from the literature on accident causation and system safety: Review of major ideas, recent contributions, and challenges

International Nuclear Information System (INIS)

Saleh, J.H.; Marais, K.B.; Bakolas, E.; Cowlagi, R.V.

2010-01-01

research and cross-talk across several academic disciplines must be supported and incentivized for tackling the multi-disciplinary issues of accident causation and system safety (e.g., through the creation 'academic hubs' or 'centers of excellence' dedicated to system safety); and (2) that more interactions and partnerships between academia, industry, and government (especially accident investigation agencies) on accident causation and system safety issues would be particularly useful for all involved in advancing the safety agenda, from both research and education perspectives, and for disseminating research results, safety recommendations, and lessons learned from accident investigations.

Safety issues on advanced fuel

International Nuclear Information System (INIS)

Gross, H.; Krebs, W.D.

1998-01-01

In the recent years a general discussion has started whether unsolved safety issues are related to advanced fuel. Advanced fuel is in this context a summary of features like high burnup, improved clad materials, low leakage loading pattern with high peaking factors etc. The design basis accidents RIA and Loca are of special interest for this discussion. From the Siemens point of view RIA is not a safety issue. There are sufficient margins between the enthalpy rise calculated by modern 3D methods and the fuel failures which occurred in RIA simulation tests when the effect of pulse width is taken into account. The evaluation of possible uncertainties for the established Loca criteria (17% equivalent corrosion, 1200 C clad temperature) for high burnup makes sense. But fuel with high burnup has significantly lower peaking factors than fuel with lower burnup. This gives sufficient margin counterbalancing possible uncertainties. In contrast to the above incomplete control rod insertion at higher burnup is potentially a real safety issue. Although Siemens fuel was not affected by the reported incidents they addressed the problem and checked that they have sufficient design margin for their fuel. (orig.) [de

Nuclear safety in light water reactors severe accident phenomenology

CERN Document Server

Sehgal, Bal Raj

2011-01-01

This vital reference is the only one-stop resource on how to assess, prevent, and manage severe nuclear accidents in the light water reactors (LWRs) that pose the most risk to the public. LWRs are the predominant nuclear reactor in use around the world today, and they will continue to be the most frequently utilized in the near future. Therefore, accurate determination of the safety issues associated with such reactors is central to a consideration of the risks and benefits of nuclear power. This book emphasizes the prevention and management of severe accidents to teach nuclear professionals

SEVERE ACCIDENT ISSUES RAISED BY THE FUKUSHIMA ACCIDENT AND IMPROVEMENTS SUGGESTED

OpenAIRE

SONG, JIN HO; KIM, TAE WOON

2014-01-01

This paper revisits the Fukushima accident to draw lessons in the aspect of nuclear safety considering the fact that the Fukushima accident resulted in core damage for three nuclear power plants simultaneously and that there is a high possibility of a failure of the integrity of reactor vessel and primary containment vessel. A brief review on the accident progression at Fukushima nuclear power plants is discussed to highlight the nature and characteristic of the event. As the severe accide...

Generic Safety Issue (GSI) 171 -- Engineered Safety Feature (ESF) failure from a loop subsequent to LOCA: Assessment of plant vulnerability and CDF contributions

International Nuclear Information System (INIS)

Martinez-Guridi, G.; Samanta, P.; Chu, L.; Yang, J.

1998-01-01

Generic Safety Issue 171 (GSI-171), Engineered Safety Feature (ESF) from a Loss Of Offsite Power (LOOP) subsequent to a Loss Of Coolant Accident (LOCA), deals with an accident sequence in which a LOCA is followed by a LOOP. This issue was later broadened to include a LOOP followed by a LOCA. Plants are designed to handle a simultaneous LOCA and LOOP. In this paper, the authors address the unique issues that are involved i LOCA with delayed LOOP (LOCA/LOOP) and LOOP with delayed LOCA (LOOP/LOCA) accident sequences. LOCA/LOOP accidents are analyzed further by developing event-tree/fault-tree models to quantify their contributions to core-damage frequency (CDF) in a pressurized water reactor and a boiling water reactor (PWR and a BWR). Engineering evaluation and judgments are used during quantification to estimate the unique conditions that arise in a LOCA/LOOP accident. The results show that the CDF contribution of such an accident can be a dominant contributor to plant risk, although BWRs are less vulnerable than PWRs

Safety against releases in severe accidents. Final report

International Nuclear Information System (INIS)

Lindholm, I.; Berg, Oe.; Nonboel, E.

1997-12-01

The work scope of the RAK-2 project has involved research on quantification of the effects of selected severe accident phenomena for Nordic nuclear power plants, development and testing of a computerised accident management support system and data collection and description of various mobile reactors and of different reactor types existing in the UK. The investigations of severe accident phenomena focused mainly on in-vessel melt progression, covering a numerical assessment of coolability of a degraded BWR core, the possibility and consequences of a BWR reactor to become critical during reflooding and the core melt behavior in the reactor vessel lower plenum. Simulant experiments were carried out to investigate lower head hole ablation induced by debris discharge. In addition to the in-vessel phenomena, a limited study on containment response to high pressure melt ejection in a BWR and a comparative study on fission product source term behaviour in a Swedish PWR were performed. An existing computerised accident management support system (CAMS) was further developed in the area of tracking and predictive simulation, signal validation, state identification and user interface. The first version of a probabilistic safety analysis module was developed and implemented in the system. CAMS was tested in practice with Barsebaeck data in a safety exercise with the Swedish nuclear authority. The descriptions of the key features of British reactor types, AGR, Magnox, FBR and PWR were published as data reports. Separate reports were issued also on accidents in nuclear ships and on description of key features of satellite reactors. The collected data were implemented in a common Nordic database. (au)

Reactor Safety Gap Evaluation of Accident Tolerant Components and Severe Accident Analysis

International Nuclear Information System (INIS)

Farmer, Mitchell T.; Bunt, R.; Corradini, M.; Ellison, Paul B.; Francis, M.; Gabor, John D.; Gauntt, R.; Henry, C.; Linthicum, R.; Luangdilok, W.; Lutz, R.; Paik, C.; Plys, M.; Rabiti, Cristian; Rempe, J.; Robb, K.; Wachowiak, R.

2015-01-01

The overall objective of this study was to conduct a technology gap evaluation on accident tolerant components and severe accident analysis methodologies with the goal of identifying any data and/or knowledge gaps that may exist, given the current state of light water reactor (LWR) severe accident research, and additionally augmented by insights obtained from the Fukushima accident. The ultimate benefit of this activity is that the results can be used to refine the Department of Energy's (DOE) Reactor Safety Technology (RST) research and development (R&D) program plan to address key knowledge gaps in severe accident phenomena and analyses that affect reactor safety and that are not currently being addressed by the industry or the Nuclear Regulatory Commission (NRC).

Reactor Safety Gap Evaluation of Accident Tolerant Components and Severe Accident Analysis

Energy Technology Data Exchange (ETDEWEB)

Farmer, Mitchell T. [Argonne National Lab. (ANL), Argonne, IL (United States); Bunt, R. [Southern Nuclear, Atlanta, GA (United States); Corradini, M. [Univ. of Wisconsin, Madison, WI (United States); Ellison, Paul B. [GE Power and Water, Duluth, GA (United States); Francis, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Gabor, John D. [Erin Engineering, Walnut Creek, CA (United States); Gauntt, R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Henry, C. [Fauske and Associates, Burr Ridge, IL (United States); Linthicum, R. [Exelon Corp., Chicago, IL (United States); Luangdilok, W. [Fauske and Associates, Burr Ridge, IL (United States); Lutz, R. [PWR Owners Group (PWROG); Paik, C. [Fauske and Associates, Burr Ridge, IL (United States); Plys, M. [Fauske and Associates, Burr Ridge, IL (United States); Rabiti, Cristian [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rempe, J. [Rempe and Associates LLC, Idaho Falls, ID (United States); Robb, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Wachowiak, R. [Electric Power Research Inst. (EPRI), Knovville, TN (United States)

2015-01-31

The overall objective of this study was to conduct a technology gap evaluation on accident tolerant components and severe accident analysis methodologies with the goal of identifying any data and/or knowledge gaps that may exist, given the current state of light water reactor (LWR) severe accident research, and additionally augmented by insights obtained from the Fukushima accident. The ultimate benefit of this activity is that the results can be used to refine the Department of Energy’s (DOE) Reactor Safety Technology (RST) research and development (R&D) program plan to address key knowledge gaps in severe accident phenomena and analyses that affect reactor safety and that are not currently being addressed by the industry or the Nuclear Regulatory Commission (NRC).

Severe accidents at nuclear power plants. Their risk assessment and accident management

International Nuclear Information System (INIS)

Abe, Kiyoharu.

1995-05-01

This document is to explain the severe accident issues. Severe Accidents are defined as accidents which are far beyond the design basis and result in severe damage of the core. Accidents at Three Mild Island in USA and at Chernobyl in former Soviet Union are examples of severe accidents. The causes and progressions of the accidents as well as the actions taken are described. Probabilistic Safety Assessment (PSA) is a method to estimate the risk of severe accidents at nuclear reactors. The methodology for PSA is briefly described and current status on its application to safety related issues is introduced. The acceptability of the risks which inherently accompany every technology is then discussed. Finally, provision of accident management in Japan is introduced, including the description of accident management measures proposed for BWRs and PWRs. (author)

Six Decades of Nuclear Accidents, Nuclear Compensation, and Issues of Radioactive Waste Management

International Nuclear Information System (INIS)

Boonsuwan, P.; Songjakkeaw, A.

2011-11-01

Thailand has made a serious aim to employ nuclear power by adopting five 1,000 MWt in the 2010 national Power Development Plan (PDP 2010) with the first NPP coming online in 2020. However, after the Fukushima nuclear disaster in March 2011, the National Energy Policy Committee had made the resolution to postpone the plan by 3 years. The post-Fukushima atmosphere does not bode well for the public sentiment towards the proposed programme, especially with regards to safety of an NPP. Nonetheless, during the six decades that NPPs have been in operation in 32 countries worldwide, there are only 19 serious accidents involving fatalities and/or damage to properties in excess of 100 million USD. Out of the three significant accidents - Fukushima nuclear accident (2011), Chernobyl nuclear accident (1986), and Three Miles Island nuclear accident (1979) - only the accident at Three Miles Island occurs during normal operation. Such can be implied that the operation of NPPs does maintain a high level of safety. The current technology on nuclear safety has been advancing greatly to the point that the new NPP design claims to render the possibility of a severe accident resulting in core melting insignificant. Along with the technical improvements, laws and regulations have also be progressing in parallel to adequately compensate and limit the liability of operators in case of a nuclear accident. The international agreements such as the Vienna Convention on Civil Liability for Nuclear Damage and the Convention of the Third Party Liability in the Field of Nuclear Energy had also been established and also the national laws of countries such as the United States and Japan have been implemented to address such issues to the point that victims of a nuclear accidents are adequately and justly compensated. In addition to the issues of nuclear accident, the dilemma in nuclear waste management, especially with regards to the High Level Waste which is highly radioactive while having very

Nuclear power systems: Their safety. Current issue review

International Nuclear Information System (INIS)

Myers, L.C.

1994-04-01

Human beings utilize energy in many forms and from a variety of sources. A number of countries have chosen nuclear-electric generation as a component of their energy system. At the end of 1992, there were 419 power reactors operating in 29 countries, accounting for more than 15% of the world's production of electricity. In 1992, 13 countries derived at least 25% of their electricity from nuclear units, with Lithuania leading at just over 78%, followed closely by France at 72%. In the same year, Canada produced about 16% of its electricity from nuclear units. Some 53 power reactors are under construction in 14 countries outside the former USSR. Within the ex-USSR countries, six new reactors are currently under construction. No human endeavour carries the guarantee of perfect safety and the question of whether of not nuclear-electric generation represents an 'acceptable' risk to society has long been vigorously debated. Until the events of late April 1986 in the then Soviet Union, nuclear safety had indeed been an issue for discussion, for some concern, but not for alarm. The accident at the Chernobyl reactor irrevocably changed all that. This disaster brought the matter of nuclear safety into the public mind in a dramatic fashion. Subsequent opening of the ex-Soviet nuclear power program to outside scrutiny has done little to calm people's concerns about the safety of nuclear power in that part of the world. This paper discusses the issue of safety in complex energy systems and provides brief accounts of some of the most serious reactor accidents that have occurred to date, as well as more recent, less dramatic events touching on the safety issue. (author). 7 refs

Analysis of National Major Work Safety Accidents in China, 2003-2012.

Science.gov (United States)

Ye, Yunfeng; Zhang, Siheng; Rao, Jiaming; Wang, Haiqing; Li, Yang; Wang, Shengyong; Dong, Xiaomei

2016-01-01

This study provides a national profile of major work safety accidents in China, which cause more than 10 fatalities per accident, intended to provide scientific basis for prevention measures and strategies to reduce major work safety accidents and deaths. Data from 2003-2012 Census of major work safety accidents were collected from State Administration of Work Safety System (SAWS). Published literature and statistical yearbook were also included to implement information. We analyzed the frequency of accidents and deaths, trend, geographic distribution and injury types. Additionally, we discussed the severity and urgency of emergency rescue by types of accidents. A total of 877 major work safety accidents were reported, resulting in 16,795 deaths and 9,183 injuries. The numbers of accidents and deaths, mortality rate and incidence of major accidents have declined in recent years. The mortality rate and incidence was 0.71 and 1.20 per 10(6) populations in 2012, respectively. Transportation and mining contributed to the highest number of major accidents and deaths. Major aviation and railway accidents caused more casualties per incident, while collapse, machinery, electrical shock accidents and tailing dam accidents were the most severe situation that resulted in bigger proportion of death. Ten years' major work safety accident data indicate that the frequency of accidents and number of eaths was declined and several safety concerns persist in some segments.

Development Of Dynamic Probabilistic Safety Assessment: The Accident Dynamic Simulator (ADS) Tool

International Nuclear Information System (INIS)

Chang, Y.H.; Mosleh, A.; Dang, V.N.

2003-01-01

The development of a dynamic methodology for Probabilistic Safety Assessment (PSA) addresses the complex interactions between the behaviour of technical systems and personnel response in the evolution of accident scenarios. This paper introduces the discrete dynamic event tree, a framework for dynamic PSA, and its implementation in the Accident Dynamic Simulator (ADS) tool. Dynamic event tree tools generate and quantify accident scenarios through coupled simulation models of the plant physical processes, its automatic systems, the equipment reliability, and the human response. The current research on the framework, the ADS tool, and on Human Reliability Analysis issues within dynamic PSA, is discussed. (author)

Development Of Dynamic Probabilistic Safety Assessment: The Accident Dynamic Simulator (ADS) Tool

Energy Technology Data Exchange (ETDEWEB)

Chang, Y.H.; Mosleh, A.; Dang, V.N

2003-03-01

The development of a dynamic methodology for Probabilistic Safety Assessment (PSA) addresses the complex interactions between the behaviour of technical systems and personnel response in the evolution of accident scenarios. This paper introduces the discrete dynamic event tree, a framework for dynamic PSA, and its implementation in the Accident Dynamic Simulator (ADS) tool. Dynamic event tree tools generate and quantify accident scenarios through coupled simulation models of the plant physical processes, its automatic systems, the equipment reliability, and the human response. The current research on the framework, the ADS tool, and on Human Reliability Analysis issues within dynamic PSA, is discussed. (author)

Gas-cooled reactor safety and accident analysis

International Nuclear Information System (INIS)

1985-12-01

The Specialists' Meeting on Gas-Cooled Reactor Safety and Accident Analysis was convened by the International Atomic Energy Agency in Oak Ridge on the invitation of the Department of Energy in Washington, USA. The meeting was hosted by the Oak Ridge National Laboratory. The purpose of the meeting was to provide an opportunity to compare and discuss results of safety and accident analysis of gas-cooled reactors under development, construction or in operation, to review their lay-out, design, and their operational performance, and to identify areas in which additional research and development are needed. The meeting emphasized the high safety margins of gas-cooled reactors and gave particular attention to the inherent safety features of small reactor units. The meeting was subdivided into four technical sessions: Safety and Related Experience with Operating Gas-Cooled Reactors (4 papers); Risk and Safety Analysis (11 papers); Accident Analysis (9 papers); Miscellaneous Related Topics (5 papers). A separate abstract was prepared for each of these papers

Safety issues of nuclear production of hydrogen

International Nuclear Information System (INIS)

Piera, Mireia; Martinez-Val, Jose M.; Jose Montes, Ma

2006-01-01

Hydrogen is not an uncommon issue in Nuclear Safety analysis, particularly in relation to severe accidents. On the other hand, hydrogen is a household name in the chemical industry, particularly in oil refineries, and is also a well known chemical element currently produced by steam reforming of natural gas, and other methods (such as coal gasification). In the not-too-distant future, hydrogen will have to be produced (by chemical reduction of water) using renewable and nuclear energy sources. In particular, nuclear fission seems to offer the cheapest way to provide the primary energy in the medium-term. Safety principles are fundamental guidelines in the design, construction and operation both of hydrogen facilities and nuclear power plants. When these two technologies are integrated, a complete safety analysis must consider not only the safety practices of each industry, but any interaction that could be established between them. In particular, any accident involving a sudden energy release from one of the facilities can affect the other. Release of dangerous substances (chemicals, radiotoxic effluents) can also pose safety problems. Although nuclear-produced hydrogen facilities will need specific approaches and detailed analysis on their safety features, a preliminary approach is presented in this paper. No significant roadblocks are identified that could hamper the deployment of this new industry, but some of the hydrogen production methods will involve very demanding safety standards

Safety against releases in severe accidents. Final report

Energy Technology Data Exchange (ETDEWEB)

Lindholm, I.; Berg, Oe.; Nonboel, E. [eds.

1997-12-01

The work scope of the RAK-2 project has involved research on quantification of the effects of selected severe accident phenomena for Nordic nuclear power plants, development and testing of a computerised accident management support system and data collection and description of various mobile reactors and of different reactor types existing in the UK. The investigations of severe accident phenomena focused mainly on in-vessel melt progression, covering a numerical assessment of coolability of a degraded BWR core, the possibility and consequences of a BWR reactor to become critical during reflooding and the core melt behavior in the reactor vessel lower plenum. Simulant experiments were carried out to investigate lower head hole ablation induced by debris discharge. In addition to the in-vessel phenomena, a limited study on containment response to high pressure melt ejection in a BWR and a comparative study on fission product source term behaviour in a Swedish PWR were performed. An existing computerised accident management support system (CAMS) was further developed in the area of tracking and predictive simulation, signal validation, state identification and user interface. The first version of a probabilistic safety analysis module was developed and implemented in the system. CAMS was tested in practice with Barsebaeck data in a safety exercise with the Swedish nuclear authority. The descriptions of the key features of British reactor types, AGR, Magnox, FBR and PWR were published as data reports. Separate reports were issued also on accidents in nuclear ships and on description of key features of satellite reactors. The collected data were implemented in a common Nordic database. (au) 39 refs.

Resolution of thermal-hydraulic safety and licensing issues for the system 80+trademark design

International Nuclear Information System (INIS)

Carpentino, S.E.; Ritterbusch, S.E.; Schneider, R.E.

1995-01-01

The System 80+ trademark Standard Design is an evolutionary Advanced Light Water Reactor (ALWR) with a generating capacity of 3931 MWt (1350 MWe). The Final Design Approval (FDA) for this design was issued by the Nuclear Regulatory Commission (NRC) in July 1994. The design certification by the NRC is anticipated by the end of 1995 or early 1996. NRC review of the System 80+ design has involved several new safety issues never before addressed in a regulatory atmosphere. In addition, conformance with the Electric Power Research Institute (EPRI) ALWR Utility Requirements Document (URD) required that the System 80+ plant address nuclear industry concerns with regard to design, construction, operation and maintenance of nuclear power plants. A large number of these issues/concerns deals with previously unresolved generic thermal-hydraulic safety issues and severe accident prevention and mitigation. This paper discusses the thermal-hydraulic analyses and evaluations performed for the System 80+ design to resolve safety and licensing issues relevant to both the Nuclear Stream Supply System (NSSS) and containment designs. For the NSSS design, the Safety Depressurization System mitigation capability and resolution of the boron dilution concern are described. Examples of containment design issues dealing with containment shell strength, robustness of the reactor cavity walls and hydrogen mixing under severe accident conditions are also provided. Finally, the overall approach used in the application of NRC's new (NUREG-1465) radiological source term for System 80+ evaluation is described. The robustness of the System 80+ containment design to withstand severe accident consequences was demonstrated through detailed thermal-hydraulic analyses and evaluations. This advanced design to shown to meet NRC severe accident policy goals and ALWR URD requirements without any special design features and unnecessary costs

Current status and issues of external event PSA for extreme natural hazards after Fukushima accident

International Nuclear Information System (INIS)

Choi, In-Kil; Hahm, Daegi; Kim, Min Kyu

2014-01-01

Extreme external events is emerged as significant risk contributor to the nuclear power plants after Fukushima Daiichi accident due to the catastrophic earthquake followed by great tsunami greater than a design basis. This accident shows that the extreme external events have the potential to simultaneously affect redundant and diverse safety systems and thereby induce common cause failure or common cause initiators. The probabilistic risk assessment methodology has been used for the risk assessment and safety improvement against the extreme natural hazards. The earthquake and tsunami hazard is an important issue for the nuclear industry in Korea. In this paper, the role and application of probabilistic safety assessment for the post Fukushima action will be introduced. For the evaluation of the extreme natural hazard, probabilistic seismic and tsunami hazard analysis is being performed for the safety enhancement. The research activity on the external event PSA and its interim results will be introduced with the issues to be solved in the future for the reliability enhancement of the risk analysis results. (authors)

Report of the Fukushima nuclear accident by the National Academy of Science. Lessons learned from the Fukushima nuclear accident for improving safety of U.S. nuclear plants

International Nuclear Information System (INIS)

Nariai, Hideki

2014-01-01

U.S. National Academy of Science investigated the accident at the Fukushima Daiichi nuclear plant initiated by the Great East Japan Earthquake for two years and published a draft report in July 24, 2014. Investigation results were summarized in nine new findings and made ten recommendations in a wide horizon; (1) hardware countermeasures against severe accidents and training of operators, (2) upgrade of risk assessment capability for beyond design basis accident, (3) incorporation of new information about hazards in safety regulations, (4) needed improvement of off-site emergency preparedness, and (5) improvements of nuclear safety culture. New information about hazards related with tsunami assessment, new risk assessment for beyond design basis accident, advice of foreigner resident evacuations, regulatory capture, and safety culture and regulator's specialty were discussed as Japanese issues. (T. Tanaka)

Safety regulations regarding to accident monitoring and accident sampling at Russian NPPs with VVER type reactors

International Nuclear Information System (INIS)

Sharafutdinov, Rachet; Lankin, Michail; Kharitonova, Nataliya

2014-01-01

The paper describes a tendency by development of regulatory document requirements related to accident monitoring and accident sampling at Russia's NPPs. Lessons learned from the Fukushima Daiichi accident pointed at the importance and necessary to carry out an additional safety check at Russia's nuclear power plants in the preparedness for management of severe accidents at NPPs. Planned measures for improvement of severe accidents management include development and implementation of the accident instrumentation systems, providing, monitoring, management and storage of information in a severe accident conditions. The draft of Safety Guidelines <accident monitoring system of nuclear power plants with VVER reactors' prepared by Scientific and Engineering Centre for Nuclear and Radiation Safety (SEC NRS) established the main criteria for accident monitoring instrumentation that can monitor relevant plant parameters in the reactor and inside containment during and after a severe accident in nuclear power plants. Development of these safety guidelines is in line with the recommendations of IAEA Action Plan on Nuclear Safety in response to the Fukushima Daiichi event and recommendations of the IAEA Nuclear Energy series Report <<Accident Monitoring Systems for Nuclear Power Plants' (Draft V 2.7). The paper presents the principles, which are used as the basis for selection of plant parameters for accident monitoring and for establishing of accident monitoring instrumentation. The recommendations to the accident sampling system capable to obtain the representative reactor coolant and containment air and fluid samples that support accurate analytical results for the parameters of interest are considered. The radiological and chemistry parameters to be monitored for primary coolant and sump and for containment air are specified. (author)

An approach to maintenance optimization where safety issues are important

International Nuclear Information System (INIS)

Vatn, Jorn; Aven, Terje

2010-01-01

The starting point for this paper is a traditional approach to maintenance optimization where an object function is used for optimizing maintenance intervals. The object function reflects maintenance cost, cost of loss of production/services, as well as safety costs, and is based on a classical cost-benefit analysis approach where a value of prevented fatality (VPF) is used to weight the importance of safety. However, the rationale for such an approach could be questioned. What is the meaning of such a VPF figure, and is it sufficient to reflect the importance of safety by calculating the expected fatality loss VPF and potential loss of lives (PLL) as being done in the cost-benefit analyses? Should the VPF be the same number for all type of accidents, or should it be increased in case of multiple fatality accidents to reflect gross accident aversion? In this paper, these issues are discussed. We conclude that we have to see beyond the expected values in situations with high safety impacts. A framework is presented which opens up for a broader decision basis, covering considerations on the potential for gross accidents, the type of uncertainties and lack of knowledge of important risk influencing factors. Decisions with a high safety impact are moved from the maintenance department to the 'Safety Board' for a broader discussion. In this way, we avoid that the object function is used in a mechanical way to optimize the maintenance and important safety-related decisions are made implicit and outside the normal arena for safety decisions, e.g. outside the traditional 'Safety Board'. A case study from the Norwegian railways is used to illustrate the discussions.

An approach to maintenance optimization where safety issues are important

Energy Technology Data Exchange (ETDEWEB)

Vatn, Jorn, E-mail: jorn.vatn@ntnu.n [NTNU, Production and Quality Engineering, 7491 Trondheim (Norway); Aven, Terje [University of Stavanger (Norway)

2010-01-15

The starting point for this paper is a traditional approach to maintenance optimization where an object function is used for optimizing maintenance intervals. The object function reflects maintenance cost, cost of loss of production/services, as well as safety costs, and is based on a classical cost-benefit analysis approach where a value of prevented fatality (VPF) is used to weight the importance of safety. However, the rationale for such an approach could be questioned. What is the meaning of such a VPF figure, and is it sufficient to reflect the importance of safety by calculating the expected fatality loss VPF and potential loss of lives (PLL) as being done in the cost-benefit analyses? Should the VPF be the same number for all type of accidents, or should it be increased in case of multiple fatality accidents to reflect gross accident aversion? In this paper, these issues are discussed. We conclude that we have to see beyond the expected values in situations with high safety impacts. A framework is presented which opens up for a broader decision basis, covering considerations on the potential for gross accidents, the type of uncertainties and lack of knowledge of important risk influencing factors. Decisions with a high safety impact are moved from the maintenance department to the 'Safety Board' for a broader discussion. In this way, we avoid that the object function is used in a mechanical way to optimize the maintenance and important safety-related decisions are made implicit and outside the normal arena for safety decisions, e.g. outside the traditional 'Safety Board'. A case study from the Norwegian railways is used to illustrate the discussions.

Nuclear reactors safety issues

International Nuclear Information System (INIS)

Barre, Francois; Seiler, Nathalie

2008-01-01

Full text of publication follows: Since the seventies, economic incentives have led the utilities to drive a permanent evolution of the light water reactor (LWR). The evolution deals with the reactor designs as well as the way to operate them in a more flexible manner. It is for instance related to the fuel technologies and management. On the one hand, the technologies are in continuous evolution, such as the fuel pellets (MOX, Gd fuel, or Cr doped fuels..) as well as advanced cladding materials (M5 TM , MDA or ZIRLO). On the other hand, the fuel management is also subject to continuous evolution in particular in terms of increasing the level of burn-up, the reactor (core) power, the enrichment, as well as the duration of reactor cycles. For instance, in a few years in France, the burn-up has raised beyond the value of 39 GWj/t, initially authorized up to 52 GWj/t for the UO 2 fuel. In the near future, utilities foreseen to reach fuel burn-up of 60 GWj/t for MOX fuel and 70 GWj/t for UO 2 fuel. Furthermore, the future reactor of fourth generation will use new fuels of advanced conception. Furthermore with the objective of improving the safety margins, methods and calculation tools used by the utilities in the elaboration of their safety demonstrations submitted to the Safety Authority, are in movement. The margin evaluation methodologies often consist of a calculation chain of best-estimate multi-field simulations (e.g. various codes being coupled to simulate in a realistic way the evolution of the thermohydraulic, neutronic and mechanic state of the reactor). The statistical methods are more and more sophisticated and the computer codes are integrating ever-complex physical models (e.g. three-dimensional at fine scale). Following this evolution, the Institute of Radioprotection and Nuclear Safety (IRSN), whose one of the roles is to examine the safety records and to rend a technical expertise, considers the necessity of reevaluating the safety issues for advanced

Pending issues for severe accident management in Wolsong plants

International Nuclear Information System (INIS)

Song, Y.M.; Kim, D.H.; Park, S.Y.

2015-01-01

While the fraction of electric power supplied from a PHWR is more than 10% in Korea, the establishment of PHWR safety enhancement based on the SAM (Severe Accident Management) technology is still weak. The final approval on the extended operation and a stress test of Wolsong-1 were made under the condition that SAM is to be enhanced. Under this situation, the current research at KAERI of Korea has a vision to strengthen the unique value of a PHWR by resolving the pending SAM issues devaluating the PHWRs’ original value. Research activities in this area will be presented. This presentation will include: The operating strategy of CFVS (Containment Filtered Vent System) for Wolsong in which vent size and closure pressure are treated because some peak spikes (at failure times of calandria and calandria vault) are difficult to be controlled; Reactor Building failure pressure at which failure probability is treated for different modes such as global and leak failures; the adequacy of DCRV (Degasser Condenser tank Relief Valve) steam relief capacity with severe SGTR source term, and Hydrogen generation and control issue which is specific to CANDU. Furthermore, current SAM guidance has a lack of information on accident diagnostic and prognostic analyses, which is difficult for the TSC (Technical Service Center) emergency staff members to deal with under real accident conditions. Thus, prototypic technologies (such as an accident inferring engine and simulator) together with SAM updates are being developed as key elements to SAM supporting tools called SAMEX-CANDU

Complementary safety assessment in the light of the Fukushima accident - Laue Langevin Institute

International Nuclear Information System (INIS)

Desbriere; Caillot; Bidet

2012-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Grenoble High Flux reactor to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the facility to withstand events beyond the level for which the facility was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence (cliff edge effect). Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like crisis organization and work organization via subcontracting are also taken into consideration. This report is divided into 9 main chapters: 1) main features of the high flux reactor, 2) macroscopic study of safety, identification of structures and equipment essential to safety, 3) earthquake risk, 4) flood risk, 5) risks due to other extreme natural disasters, 6) the loss of electrical power supplies and of cooling systems, 7) management of severe accidents, 8) subcontracting policy, 9) synthesis and improvements. This study confirms the robustness of the facility and a series of improvements and modifications is proposed to face very unlikely situations (especially plurality of failures) that were not taken into account in baseline safety studies. (A.C.)

Implications of the Fukushima accident of nuclear safety in Finland

International Nuclear Information System (INIS)

Valtonen, Keijo

2012-01-01

A severe accident took place in Japan at Fukushima Dai-ichi nuclear power plant in March 2011. The immediate cause of the accident was a tsunami caused by the earthquake and the fact that the consequences of large tsunamis were not adequately considered in the design of the plant. Although tsunamis are not considered a real threat in Europe, the European Council requested on 25 March 2011 the European Nuclear Safety Regulators' Group (ENSREG) and the European Commission to undertake a comprehensive and transparent risk and safety assessment (''stress test'') of European nuclear power plants [ENSREG 2011A]. This report is prepared to evaluate the safety provisions of Finnish Nuclear Power Plants as specified in the European ''stress tests''. The technical description is based on the Licensees' reports on the issues within these specifications [Fortum 2011; TVO 2011]. Furthermore, evaluation on the current situation carried out by Radiation and Nuclear Safety Authority (STUK) is provided, and the possibilities to further enhance safety in the Finnish NPPs are presented. According to the ENSREG specifications, earthquakes, flooding and extreme weather conditions were studied in the stress tests. In addition, consequences of losses of some safety functions and finally management of severe accidents were studied, irrespective of their probabilities. The European stress tests cover in Finland all the operating nuclear power plants (Loviisa 1 and 2, Olkiluoto 1 and 2) and the unit under construction (Olkiluoto 3). The intermediate storages of spent fuel in Loviisa and in Olkiluoto are included in the stress tests. The new NPP units to be constructed which do not yet have a construction license, (Fennovoima 1, Olkiluoto 4) are not considered in the European stress tests. (orig.)

Safety culture and accident analysis-A socio-management approach based on organizational safety social capital

International Nuclear Information System (INIS)

Rao, Suman

2007-01-01

One of the biggest challenges for organizations in today's competitive business environment is to create and preserve a self-sustaining safety culture. Typically, Key drivers of safety culture in many organizations are regulation, audits, safety training, various types of employee exhortations to comply with safety norms, etc. However, less evident factors like networking relationships and social trust amongst employees, as also extended networking relationships and social trust of organizations with external stakeholders like government, suppliers, regulators, etc., which constitute the safety social capital in the Organization-seem to also influence the sustenance of organizational safety culture. Can erosion in safety social capital cause deterioration in safety culture and contribute to accidents? If so, how does it contribute? As existing accident analysis models do not provide answers to these questions, CAMSoC (Curtailing Accidents by Managing Social Capital), an accident analysis model, is proposed. As an illustration, five accidents: Bhopal (India), Hyatt Regency (USA), Tenerife (Canary Islands), Westray (Canada) and Exxon Valdez (USA) have been analyzed using CAMSoC. This limited cross-industry analysis provides two key socio-management insights: the biggest source of motivation that causes deviant behavior leading to accidents is 'Faulty Value Systems'. The second biggest source is 'Enforceable Trust'. From a management control perspective, deterioration in safety culture and resultant accidents is more due to the 'action controls' rather than explicit 'cultural controls'. Future research directions to enhance the model's utility through layering are addressed briefly

Resolution of thermal-hydraulic safety and licensing issues for the system 80+{sup {trademark}} design

Energy Technology Data Exchange (ETDEWEB)

Carpentino, S.E.; Ritterbusch, S.E.; Schneider, R.E. [ABB-Combustion Engineering, Windsor, CT (United States)] [and others

1995-09-01

The System 80+{sup {trademark}} Standard Design is an evolutionary Advanced Light Water Reactor (ALWR) with a generating capacity of 3931 MWt (1350 MWe). The Final Design Approval (FDA) for this design was issued by the Nuclear Regulatory Commission (NRC) in July 1994. The design certification by the NRC is anticipated by the end of 1995 or early 1996. NRC review of the System 80+ design has involved several new safety issues never before addressed in a regulatory atmosphere. In addition, conformance with the Electric Power Research Institute (EPRI) ALWR Utility Requirements Document (URD) required that the System 80+ plant address nuclear industry concerns with regard to design, construction, operation and maintenance of nuclear power plants. A large number of these issues/concerns deals with previously unresolved generic thermal-hydraulic safety issues and severe accident prevention and mitigation. This paper discusses the thermal-hydraulic analyses and evaluations performed for the System 80+ design to resolve safety and licensing issues relevant to both the Nuclear Stream Supply System (NSSS) and containment designs. For the NSSS design, the Safety Depressurization System mitigation capability and resolution of the boron dilution concern are described. Examples of containment design issues dealing with containment shell strength, robustness of the reactor cavity walls and hydrogen mixing under severe accident conditions are also provided. Finally, the overall approach used in the application of NRC`s new (NUREG-1465) radiological source term for System 80+ evaluation is described. The robustness of the System 80+ containment design to withstand severe accident consequences was demonstrated through detailed thermal-hydraulic analyses and evaluations. This advanced design to shown to meet NRC severe accident policy goals and ALWR URD requirements without any special design features and unnecessary costs.

Analysis of National Major Work Safety Accidents in China, 2003–2012

Science.gov (United States)

YE, Yunfeng; ZHANG, Siheng; RAO, Jiaming; WANG, Haiqing; LI, Yang; WANG, Shengyong; DONG, Xiaomei

2016-01-01

Background: This study provides a national profile of major work safety accidents in China, which cause more than 10 fatalities per accident, intended to provide scientific basis for prevention measures and strategies to reduce major work safety accidents and deaths. Methods: Data from 2003–2012 Census of major work safety accidents were collected from State Administration of Work Safety System (SAWS). Published literature and statistical yearbook were also included to implement information. We analyzed the frequency of accidents and deaths, trend, geographic distribution and injury types. Additionally, we discussed the severity and urgency of emergency rescue by types of accidents. Results: A total of 877 major work safety accidents were reported, resulting in 16,795 deaths and 9,183 injuries. The numbers of accidents and deaths, mortality rate and incidence of major accidents have declined in recent years. The mortality rate and incidence was 0.71 and 1.20 per 106 populations in 2012, respectively. Transportation and mining contributed to the highest number of major accidents and deaths. Major aviation and railway accidents caused more casualties per incident, while collapse, machinery, electrical shock accidents and tailing dam accidents were the most severe situation that resulted in bigger proportion of death. Conclusion: Ten years’ major work safety accident data indicate that the frequency of accidents and number of eaths was declined and several safety concerns persist in some segments. PMID:27057515

Safety culture and accident analysis-A socio-management approach based on organizational safety social capital

Energy Technology Data Exchange (ETDEWEB)

Rao, Suman [Risk Analyst (India)]. E-mail: sumanashokrao@yahoo.co.in

2007-04-11

One of the biggest challenges for organizations in today's competitive business environment is to create and preserve a self-sustaining safety culture. Typically, Key drivers of safety culture in many organizations are regulation, audits, safety training, various types of employee exhortations to comply with safety norms, etc. However, less evident factors like networking relationships and social trust amongst employees, as also extended networking relationships and social trust of organizations with external stakeholders like government, suppliers, regulators, etc., which constitute the safety social capital in the Organization-seem to also influence the sustenance of organizational safety culture. Can erosion in safety social capital cause deterioration in safety culture and contribute to accidents? If so, how does it contribute? As existing accident analysis models do not provide answers to these questions, CAMSoC (Curtailing Accidents by Managing Social Capital), an accident analysis model, is proposed. As an illustration, five accidents: Bhopal (India), Hyatt Regency (USA), Tenerife (Canary Islands), Westray (Canada) and Exxon Valdez (USA) have been analyzed using CAMSoC. This limited cross-industry analysis provides two key socio-management insights: the biggest source of motivation that causes deviant behavior leading to accidents is 'Faulty Value Systems'. The second biggest source is 'Enforceable Trust'. From a management control perspective, deterioration in safety culture and resultant accidents is more due to the 'action controls' rather than explicit 'cultural controls'. Future research directions to enhance the model's utility through layering are addressed briefly.

Status of the French R/D program on the severe accident issue to develop Gen IV SFRs - 15373

International Nuclear Information System (INIS)

Serre, F.; Bertrand, F.; Journeau, C.; Suteau, C.; Verwaede, D.; Schmitt, D.; Farges, B.

2015-01-01

The ASTRID reactor (Advanced Sodium Technological Reactor for Industrial Demonstration) is a technological demonstrator designed by the CEA with its industrial partners, with very high levels of requirements. In the ASTRID project, the safety objectives are to prevent core melting, in particular by the development of an innovative core with complementary safety prevention devices, and to enhance the reactor resistance to severe accident by design. To mitigate the consequences of hypothetical core melting situations, specific dispositions or mitigation devices will be added to the core and to the reactor. It is also required to provide a robust safety demonstration (with high level of confidence). Therefore a new approach for severe accident issue has been defined: to the well-known 'lines of defense' method, a 'lines of mitigation' method is added. To meet these ASTRID, or future SFR, requirements, a large R/D program was launched in the Severe Accident domain, with a large number of partners. This paper will present the status of the CEA R/D related to the SFR Severe Accident issue, the collaboration framework (with industrial partners and R/D foreign organizations), and the future R/D plans to support the ASTRID project and possible developments for future Gen IV commercial SFR. (authors)

Inroads into Equestrian Safety: Rider-Reported Factors Contributing to Horse-Related Accidents and Near Misses on Australian Roads

Science.gov (United States)

Thompson, Kirrilly; Matthews, Chelsea

2015-01-01

Simple Summary Riding horses on roads can be dangerous, but little is known about accidents and near misses. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey, mostly attributed to speed. Whilst our findings confirmed factors identified overseas, we also identified issues around road rules, hand signals and road rage. This paper suggests strategies for improving the safety of horses, riders and other road users. Abstract Horse riding and horse-related interactions are inherently dangerous. When they occur on public roads, the risk profile of equestrian activities is complicated by interactions with other road users. Research has identified speed, proximity, visibility, conspicuity and mutual misunderstanding as factors contributing to accidents and near misses. However, little is known about their significance or incidence in Australia. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey. Whilst our findings confirm the factors identified overseas, we also identified issues around rider misunderstanding of road rules and driver misunderstanding of rider hand signals. Of particular concern, we also found reports of potentially dangerous rider-directed road rage. We identify several areas for potential safety intervention including (1) identifying equestrians as vulnerable road users and horses as sentient decision-making vehicles; (2) harmonising laws regarding passing horses; (3) mandating personal protective equipment; (4) improving road signage; (5) comprehensive data collection; (6) developing mutual understanding amongst road-users; (7) safer road design and alternative riding spaces; and (8) increasing investment

Preliminary safety analysis of the PWR with accident-tolerant fuels during severe accident conditions

International Nuclear Information System (INIS)

Wu, Xiaoli; Li, Wei; Wang, Yang; Zhang, Yapei; Tian, Wenxi; Su, Guanghui; Qiu, Suizheng; Liu, Tong; Deng, Yongjun; Huang, Heng

2015-01-01

Highlights: • Analysis of severe accident scenarios for a PWR fueled with ATF system is performed. • A large-break LOCA without ECCS is analyzed for the PWR fueled with ATF system. • Extended SBO cases are discussed for the PWR fueled with ATF system. • The accident-tolerance of ATF system for application in PWR is illustrated. - Abstract: Experience gained in decades of nuclear safety research and previous nuclear accidents direct to the investigation of passive safety system design and accident-tolerant fuel (ATF) system which is now becoming a hot research point in the nuclear energy field. The ATF system is aimed at upgrading safety characteristics of the nuclear fuel and cladding in a reactor core where active cooling has been lost, and is preferable or comparable to the current UO 2 –Zr system when the reactor is in normal operation. By virtue of advanced materials with improved properties, the ATF system will obviously slow down the progression of accidents, allowing wider margin of time for the mitigation measures to work. Specifically, the simulation and analysis of a large break loss of coolant accident (LBLOCA) without ECCS and extended station blackout (SBO) severe accident are performed for a pressurized water reactor (PWR) loaded with ATF candidates, to reflect the accident-tolerance of ATF

Safety criteria for the future LMFBR's in France and main safety issues for the rapide 1500 project

International Nuclear Information System (INIS)

Justin, F.; Natta, M.; Orzoni, G.

1985-04-01

The main safety criteria for future LMFBR in France and the related issues for the RAPIDE 1500 project are presented and discussed. The evolutions with respect to SUPERPHENIX options and requirements are emphasized, in particular for the concerns of the prevention of core melt accidents, fuel damage limits and related required performances of the protection system, since one main option is not to consider whole core melt accidents in the containment design. One shall also point out the advantages of some mitigating features which were nevertheless added in the containment design, although without any explicit consideration for core melt accidents

Safety issues at the defense production reactors

International Nuclear Information System (INIS)

1987-01-01

The United States produces plutonium and tritium for use in nuclear weapons at the defense production reactors - the N Reactor in Washington and the Savannah River reactors in South Carolina. This report reaches general conclusions about the management of those reactors and highlights a number of safety and technical issues that should be resolved. The report provides an assessment of the safety management, safety review, and safety methodology employed by the Department of Energy and the private contractors who operate the reactors for the federal government. This report examines the safety objective established by the Department of Energy for the production reactors and the process the Department of its contractors use to implement the objective; focuses on a variety of uncertainties concerning the production reactors, particularly those related to potential vulnerabilities to severe accidents; and identifies ways in which the DOE approach to management of the safety of the production reactors can be improved

The Fukushima Daiichi Accident. Technical Volume 2/5. Safety Assessment

International Nuclear Information System (INIS)

2015-08-01

Technical Volume 1 of this report has described what happened during the accident at the Fukushima Daiichi nuclear power plant (NPP). This volume begins (Section 2.1) with a review of how the design basis of the site for external events was assessed initially and then reassessed over the life of the NPP. The section also describes the physical changes that were made to the units as a result. The remainder of the volume describes the treatment of beyond design basis events in the safety assessment of the site, the accident management provisions, the effectiveness of regulatory programmes, human and organizational factors and the safety culture, and the role of operating experience. Further background information is contained in three annexes included on the CD-ROM of this Technical Volume which describe analytical investigations of the accident along with information on topics such as system performance, defence in depth and severe accident phenomena. Section 2.2 provides an assessment of the systems that failed, resulting in a failure to maintain the fundamental safety functions in Units 1–3, which were in operation at the time of the tsunami and in which the reactor pressure vessels (RPV) and containment vessels failed. The section also describes Units 4-6, which were shut down at the time of the tsunami, and the site’s central spent fuel storage facility. Section 2.3 discusses the probabilistic and deterministic safety assessments of beyond design basis accidents (BDBAs) that had been performed for the plant and the insights from these assessments that had led to changes in the plant’s design. The section pays particular attention to the assessment of extreme natural hazards, such as the one which led to the total loss of AC power supply on the site. The additional loss of DC power supply in Units 1 and 2 played a key role in the progression of the accident because it impeded the diagnosis of plant conditions and made the operators unaware of the status of

Safety analysis of accident localization system

International Nuclear Information System (INIS)

1999-01-01

A complex safety analysis of accident localization system of Ignalina NPP was performed. Calculation results obtained, results of non-destruct ing testing and experimental data of reinforced concrete testing of buildings does not revealed deficiencies of buildings of accident localization system at unit 1 of Ignalina NPP. Calculations were performed using codes NEPTUNE, ALGOR, CONTAIN

Effect of Occupational Health and Safety Management System on Work-Related Accident Rate and Differences of Occupational Health and Safety Management System Awareness between Managers in South Korea's Construction Industry

OpenAIRE

Yoon, Seok J.; Lin, Hsing K.; Chen, Gang; Yi, Shinjea; Choi, Jeawook; Rui, Zhenhua

2013-01-01

Background: The study was conducted to investigate the current status of the occupational health and safety management system (OHSMS) in the construction industry and the effect of OHSMS on accident rates. Differences of awareness levels on safety issues among site general managers and occupational health and safety (OHS) managers are identified through surveys. Methods: The accident rates for the OHSMS-certified construction companies from 2006 to 2011, when the construction OHSMS became ...

Addressing the fundamental issues in reliability evaluation of passive safety of AP1000 for a comparison with active safety of PWR

International Nuclear Information System (INIS)

Hashim Muhammad; Yoshikawa, Hidekazu; Yang Ming

2013-01-01

Passive safety systems adopted in advanced Pressurized Water Reactor (PWR), such as AP1000 and EPR, should attain higher reliability than the existing active safety systems of the conventional PWR. The objective of this study is to discuss the fundamental issues relating to the reliability evaluation of AP1000 passive safety systems for a comparison with the active safety systems of conventional PWR, based on several aspects. First, comparisons between conventional PWR and AP1000 are made from the both aspects of safety design and cost reduction. The main differences between these PWR plants exist in the configurations of safety systems: AP1000 employs the passive safety system while reducing the number of active systems. Second, the safety of AP1000 is discussed from the aspect of severe accident prevention in the event of large break loss of coolant accidents (LOCA). Third, detailed fundamental issues on reliability evaluation of AP1000 passive safety systems are discussed qualitatively by using single loop models of safety systems of both PWRs plants. Lastly, methodology to conduct quantitative estimation of dynamic reliability for AP1000 passive safety systems in LOCA condition is discussed, in order to evaluate the reliability of AP1000 in future by a success-path-based reliability analysis method (i.e., GO-FLOW). (author)

The post-accident nuclear issue: the new crisis expertise challenges for the IRSN

International Nuclear Information System (INIS)

Champion, D.

2010-01-01

The author reports the work performed by two work groups conducted by the IRSN (the French Radioprotection and Nuclear Safety Institute), the first one on the issue of assessment of radiological and dosimetric consequences in a post-accident situation, and the second one on hypotheses to be used to perform predictive assessments of these consequences. First dealing with the end of the emergency phase, he describes how to anticipate actions of protection against immediate post-accident consequences: orientation of the expertise strategy based on the CODIRPA's doctrine, post-accident zoning based on predictive indicators, use of reasonably prudent hypotheses for the first predictive assessments, importance of initial radioactive deposits to perform predictive assessments. Then, the author presents an iterative method of assessment of post-accident consequences: organization of environment radioactivity measurement programmes, periodic update of mapping of initial deposit and of actual deposits at a given time

Safety assurance logic techniques for evaluation of accident prevention and mitigation

International Nuclear Information System (INIS)

McWethy, L.M.; Hagan, J.W.

1976-01-01

Safety assurance methods have been developed and applied in reactor safety assessments of FFTF. These methods promote visibility of the total safety provided by the plant, both in prevention of off-normal or accident conditions as well as provision of various features which terminate conditions within acceptable bounds if such conditions should occur. One of the primary techniques applied in safety assurance is the development of safety assurance diagrams. These diagrams explicitly identify the multiple lines of defense which prevent accident progression. The diagrams graphically demonstrate the defense-in-depth provided by the plant for each postulated occurrence. Lines of defense are shown against ever having an occurrence in the first place; thus giving appropriate emphasis on accident prevention, and visibility to the designer's role in promoting this level of safety. These diagrams, or accident process trees, also show graphically the various paths of postulated accident progression to their logical termination. Evaluation of the importance and strength of each line-of-defense assures fulfillment of the safety objectives of the overall plant system

Status of safety issues at licensed power plants: TMI Action Plan requirements, unresolved safety issues, generic safety issues, other multiplant action issues

International Nuclear Information System (INIS)

1992-12-01

This report is to provide a comprehensive description of the implementation and verification status of Three Mile Island (TMI) Action Plan requirements, safety issues designated as Unresolved Safety Issues (USIs), Generic Safety Issues(GSIs), and other Multiplant Actions (MPAs) that have been resolved and involve implementation of an action or actions by licensees. This report makes the information available to other interested parties, including the public. An additional purpose of this NUREG report is to serve as a follow-on to NUREG-0933, ''A Prioritization of Generic Safety Issues,'' which tracks safety issues up until requirements are approved for imposition at licensed plants or until the NRC issues a request for action by licensees

Review of EU-APR Design for Selected Safety Issues of WERNA RHWG 2013

Energy Technology Data Exchange (ETDEWEB)

Kim, Yong Soo; Kim, Ji Hwan [KHNP CRI, Daejeon (Korea, Republic of)

2016-10-15

Western European Nuclear Regulators' Association (WENRA) was established in 1999 to develop a harmonized approach to nuclear safety and radiation protection and their regulation. In 2013, the Reactor Harmonization Working Group (RHWG) of WENRA sets out the common positions on the seven selected key safety issues. This paper is to introduce the regulatory positions of WENRA RHWG 2013 and to review the compliance of the EU-APR with them. In this paper, we reviewed the compliance of the EUAPR regarding seven safety issues for new NPPs presented by WERNA RHWG in 2013. The EU-APR design fully complies with all WERNA RHWG safety issues since the following measures have been incorporated in it: - Successive five levels of DiD maintaining independence between different levels of DiD - Diverse design against multiple failure events such as ATWS, SBO, Loss of Ultimate Heat Sink, and Loss of Spent Fuel Pool Cooling - SAs dedicated mitigation systems to ensure the containment integrity during the SAs. - Practically eliminates accident sequences with a large or early release of radiological materials by diverse designs for multiple failure events, SAs dedicated mitigation system, and double containment design - Standard site parameters not lead to core melt accidents due to natural or man-made external hazards.

Issues and challenges for pedestrian active safety systems based on real world accidents.

Science.gov (United States)

Hamdane, Hédi; Serre, Thierry; Masson, Catherine; Anderson, Robert

2015-09-01

The purpose of this study was to analyze real crashes involving pedestrians in order to evaluate the potential effectiveness of autonomous emergency braking systems (AEB) in pedestrian protection. A sample of 100 real accident cases were reconstructed providing a comprehensive set of data describing the interaction between the vehicle, the environment and the pedestrian all along the scenario of the accident. A generic AEB system based on a camera sensor for pedestrian detection was modeled in order to identify the functionality of its different attributes in the timeline of each crash scenario. These attributes were assessed to determine their impact on pedestrian safety. The influence of the detection and the activation of the AEB system were explored by varying the field of view (FOV) of the sensor and the level of deceleration. A FOV of 35° was estimated to be required to detect and react to the majority of crash scenarios. For the reaction of a system (from hazard detection to triggering the brakes), between 0.5 and 1s appears necessary. Copyright © 2015 Elsevier Ltd. All rights reserved.

Safety culture and the accident at Three Mile Island

International Nuclear Information System (INIS)

Erp, Jan B. van

2002-01-01

Prior to the accident at Three Mile Island, little attention was being paid to the human role in the safe operation of civilian nuclear power plants. The investigation of the TMI accident showed that its root causes were primarily human-related. The Kemeny Report on the TMI accident does not use the term 'safety culture'; however, it fully identifies all relevant aspects of safety culture. It was only after the accident at Chernobyl that the term 'safety culture' came into widespread use. However, it should be noted that, during the years after TMI and before Chernobyl, already major changes had been instituted concerning human factors and human reliability in the civilian nuclear energy programs of many countries. Greater credit should be given to the remarkable insights developed by the Kemeny Commission as contained in the Kemeny Report. (author)

The Fukushima Daiichi Nuclear Power Plant Accident: OECD/NEA Nuclear Safety Response and Lessons Learnt

International Nuclear Information System (INIS)

2013-01-01

Following the March 2011 accident at the Fukushima Daiichi nuclear power plant, all NEA member countries took early action to ensure and confirm the continued safety of their nuclear power plants and the protection of the public. After these preliminary safety reviews, all countries with nuclear facilities carried out comprehensive safety reviews, often referred to as 'stress tests', which reassessed safety margins of nuclear facilities with a primary focus on challenges related to conditions experienced at the Fukushima Daiichi nuclear power plant, for example extreme external events and the loss of safety functions, or capabilities to cope with severe accidents. As appropriate, improvements are being made to safety and emergency response systems to ensure that nuclear power plants are capable of withstanding events that lead to loss of electrical power and/or cooling capability. In the weeks following the accident, the NEA immediately began establishing expert groups in the nuclear safety and radiological protection areas, as well as contributing to information exchange with the Japanese authorities and other international organisations. It promptly provided a forum for high-level decision makers and regulators within the G8-G20 frameworks. The NEA actions taken at the international level in response to the accident have been carried out primarily by the three NEA standing technical committees concerned with nuclear and radiation safety issues - the Committee on Nuclear Regulatory Activities (CNRA), the Committee on the Safety of Nuclear Installations (CSNI) and the Committee on Radiation Protection and Public Health (CRPPH) - under the leadership of the CNRA. More than two years following the accident, the NEA continues to assist the Japanese authorities in dealing with their nuclear safety and recovery efforts as well as to facilitate international co-operation on nuclear safety and radiological protection matters. It is strongly supporting the establishment of

Confined Site Construction: A qualitative investigation of critical issues affecting management of Health and Safety

OpenAIRE

Spillane, John P.; Oyedele, Lukumon O.; Von Meding, Jason; Konanahalli, Ashwini; Jaiyeoba, Babatunde E.; Tijani, Iyabo K.

2011-01-01

The construction industry is inherently risky, with a significant number of accidents and disasters occurring, particularly on confined construction sites. This research investigates and identifies the various issues affecting successful management of health and safety in confined construction sites. The rationale is that identifying the issues would assist the management of health and safety particularly in inner city centres which are mostly confined sites. Using empiricism epistemology, th...

Safety issues for LMFBR: important features drawn from the assessments of Superphenix

International Nuclear Information System (INIS)

Natta, M.

2002-01-01

Superphenix, which is built on the site of Creys-Malville, is still the biggest LMFBR plant that has been in operation. It is a pool type reactor, as Phenix and the RNR 1 500 and EFR projects. After the analysis of the preliminary safety (1974-1975), the construction was authorised by decree of the Prime Minister in 1977, the authorization for fuel loading and star-up to 3% was given by the minister of industry in July 1985 and full power was achieved in December 1986. The plant was operated until the end of December 1996, producing the equivalent of 320 EFPD, corresponding to half of the maximum barn-up of the first core. The plant was definitively stopped on the 20. of April 1998 by a decision of the French government. During this period of 25 years of licensing, construction and operation of Superphenix, others discussions and preliminary licensing procedures were started for new projects, mainly the RNR 1500 French project and the EFR European project. The operation of Superphenix was also marked by several incidents, which led to additional licensing procedures and important modifications. This period was also marked by an important work of research and development in the safety field, mostly related to the issues concerning hypothetical core disruptive accidents (HCDA) and sodium fires; further, this period was marked by the Three Mile Island accident in 1979 and the Chernobyl accident in 1986. The purpose of this paper is to present some items which were discussed during this period of 25 years and which should be of interest for future LMFBRs. In this presentation, we shall discuss the key issues concerning the safety criteria and options taken with respect to severe accidents, i.e. core melt accidents, giving details on some specific which are less known since they were assessed only lately for Superphenix, sometimes in connection with the on-going safety researches. (author)

ROAD ACCIDENT AND SAFETY STUDY IN SYLHET REGION OF BANGLADESH

Directory of Open Access Journals (Sweden)

B. K. BANIK

2011-08-01

Full Text Available Roads, highways and streets are fundamental infrastructure facilities to provide the transportation for passenger travel and goods movement from one place to another in Sylhet, north–eastern division of Bangladesh with rapid growth of road vehicle, being comparatively developed economic tourist prone area faces severe road traffic accident. Such severe road accidents cause harsh safety hazards on the roads of Sylhet area. This research work presents an overview of the road traffic accident and degraded road safety situation in Sylhet zone which in particular, discusses the key road accident problem characteristics identifying the hazardous roads and spots, most responsible vehicles and related components, conditions of drivers and pedestrians, most victims of accident, effects of accident on society, safety priorities and options available in Sylhet. In this regard, a comprehensive questionnaire survey was conducted on the concerned groups of transportation and detailed accident data was collected from a popular local newspaper. Analysis of the study reveals that Dhaka- Sylhet highway is the most hazardous in road basis and Sylhet Sador thana is the most vulnerable in thana basis in Sylhet region.

Mitigation of Severe Accident Consequences Using Inherent Safety Principles

International Nuclear Information System (INIS)

Wigeland, R.A.; Cahalan, J.E.

2009-01-01

Sodium-cooled fast reactors are designed to have a high level of safety. Events of high probability of occurrence are typically handled without consequence through reliable engineering systems and good design practices. For accidents of lower probability, the initiating events are characterized by larger and more numerous challenges to the reactor system, such as failure of one or more major engineered systems and can also include a failure to scram the reactor in response. As the initiating conditions become more severe, they have the potential for creating serious consequences of potential safety significance, including fuel melting, fuel pin disruption and recriticality. If the progression of such accidents is not mitigated by design features of the reactor, energetic events and dispersal of radioactive materials may result. For severe accidents, there are several approaches that can be used to mitigate the consequences of such severe accident initiators, which typically include fuel pin failures and core disruption. One approach is to increase the reliability of the reactor protection system so that the probability of an ATWS event is reduced to less than 1 x 10-6 per reactor year, where larger accident consequences are allowed, meeting the U.S. NRC goal of relegating such accident consequences as core disruption to these extremely low probabilities. The main difficulty with this approach is to convincingly test and guarantee such increased reliability. Another approach is to increase the redundancy of the reactor scram system, which can also reduce the probability of an ATWS event to a frequency of less than 1 x 10-6 per reactor year or lower. The issues with this approach are more related to reactor core design, with the need for a greater number of control rod positions in the reactor core and the associated increase in complexity of the reactor protection system. A third approach is to use the inherent reactivity feedback that occurs in a fast reactor to

Safety analysis results for cryostat ingress accidents in ITER

International Nuclear Information System (INIS)

Merrill, B.J.; Cadwallader, L.C.; Petti, D.A.

1996-01-01

Accidents involving the ingress of air or water into the cryostat of the International Thermonuclear Experimental Reactor (ITER) tokamak design have been analyzed with a modified version of the MELCOR code for the ITER Non-site Specific Safety Report (NSSR-1). The air ingress accident is the result of a postulated breach of the cryostat boundary into an adjoining room. MELCOR results for this accident demonstrate that the condensed air mass and increased heat loads are not a magnet safety concern, but that the partial vacuum in the adjoining room must be accommodated in the building design. The water ingress accident is the result of a postulated magnet arc that results in melting of a Primary Heat Transport System (PHTS) coolant pipe, discharging PHTS water and PHTS water activated corrosion products and HTO into the cryostat. MELCOR results for this accident demonstrate that the condensed water mass and increased heat loads are not a magnet safety concern, that the cryostat pressure remains below design limits, and that the corrosion product and HTO releases are well within the ITER release limits

Circuit board accident--organizational dimension hidden by prescribed safety.

Science.gov (United States)

de Almeida, Ildeberto Muniz; Buoso, Eduardo; do Amaral Dias, Maria Dionísia; Vilela, Rodolfo Andrade Gouveia

2012-01-01

This study analyzes an accident in which two maintenance workers suffered severe burns while replacing a circuit breaker panel in a steel mill, following model of analysis and prevention of accidents (MAPA) developed with the objective of enlarging the perimeter of interventions and contributing to deconstruction of blame attribution practices. The study was based on materials produced by a health service team in an in-depth analysis of the accident. The analysis shows that decisions related to system modernization were taken without considering their implications in maintenance scheduling and creating conflicts of priorities and of interests between production and safety; and also reveals that the lack of a systemic perspective in safety management was its principal failure. To explain the accident as merely non-fulfillment of idealized formal safety rules feeds practices of blame attribution supported by alibi norms and inhibits possible prevention. In contrast, accident analyses undertaken in worker health surveillance services show potential to reveal origins of these events incubated in the history of the system ignored in practices guided by the traditional paradigm.

Editorial: emerging issues in sociotechnical systems thinking and workplace safety.

Science.gov (United States)

Noy, Y Ian; Hettinger, Lawrence J; Dainoff, Marvin J; Carayon, Pascale; Leveson, Nancy G; Robertson, Michelle M; Courtney, Theodore K

2015-01-01

The burden of on-the-job accidents and fatalities and the harm of associated human suffering continue to present an important challenge for safety researchers and practitioners. While significant improvements have been achieved in recent decades, the workplace accident rate remains unacceptably high. This has spurred interest in the development of novel research approaches, with particular interest in the systemic influences of social/organisational and technological factors. In response, the Hopkinton Conference on Sociotechnical Systems and Safety was organised to assess the current state of knowledge in the area and to identify research priorities. Over the course of several months prior to the conference, leading international experts drafted collaborative, state-of-the-art reviews covering various aspects of sociotechnical systems and safety. These papers, presented in this special issue, cover topics ranging from the identification of key concepts and definitions to sociotechnical characteristics of safe and unsafe organisations. This paper provides an overview of the conference and introduces key themes and topics. Sociotechnical approaches to workplace safety are intended to draw practitioners' attention to the critical influence that systemic social/organisational and technological factors exert on safety-relevant outcomes. This paper introduces major themes addressed in the Hopkinton Conference within the context of current workplace safety research and practice challenges.

Chemical Hazards and Safety Issues in Fusion Safety Design

International Nuclear Information System (INIS)

Cadwallader, L.C.

2003-01-01

Radiological inventory releases have dominated accident consequences for fusion; these consequences are important to analyze and are generally the most severe result of a fusion facility accident event. However, the advent of, or plan for, large-scale usage of some toxic materials poses the additional hazard of chemical exposure from an accident event. Examples of toxic chemicals are beryllium for magnetic fusion and fluorine for laser fusion. Therefore, chemical exposure consequences must also be addressed in fusion safety assessment. This paper provides guidance for fusion safety analysis. US Department of Energy (DOE) chemical safety assessment practices for workers and the public are reviewed. The US Environmental Protection Agency (EPA) has published some guidance on public exposure to releases of mixtures of chemicals, this guidance has been used to create an initial guideline for treating mixed radiological and toxicological releases in fusion; for example, tritiated hazardous dust from a tokamak vacuum vessel. There is no convenient means to judge the hazard severity of exposure to mixed materials. The chemical fate of mixed material constituents must be reviewed to determine if there is a separate or combined radiological and toxicological carcinogenesis, or if other health threats exist with radiological carcinogenesis. Recommendations are made for fusion facility chemical safety evaluation and safety guidance for protecting the public from chemical releases, since such levels are not specifically identified in the DOE fusion safety standard

Safety issues to be taken into account in designing future nuclear fusion facilities

Energy Technology Data Exchange (ETDEWEB)

Perrault, Didier, E-mail: didier.perrault@irsn.fr

2016-11-01

Highlights: • Assess if decay heat removal is a safety function. • Re-study accidents considered for ITER and identify those specific to DEMO. • Limit tritium inventory and optimize main gaseous tritium release routes. • Take into account constraints related to requirements of waste disposal routes. - Abstract: For several years now, the French “Institut de Radioprotection et de Sûreté Nucléaire” has been carrying out expertise of ITER fusion facility safety files at the request of the French “Autorité de Sûreté Nucléaire”. As part of the lengthy process which should lead to mastering nuclear fusion, different fusion facility projects are currently under study throughout the world to be ready to continue building on the work which will take place in the ITER facility. On the basis of the experience acquired during the ITER safety expertise, the IRSN has carried out a preliminary study of the safety issues which seem necessary to take into account right from the earliest design phase of these DEMO facilities. The issues studied have included the decay heat removal, exposure to ionizing radiation, potential accidents, and effluent releases and waste. The study shows that it will be important to give priority to the following actions, given that their results would have a major influence on the design: assess if decay heat removal is a safety function, re-study the accidents considered in the context of the ITER project and identify those specific to DEMO, and optimize each of the main routes for gaseous tritium releases.

Nuclear Reactor RA Safety Report, Vol. 13, Causes of possible accidents

International Nuclear Information System (INIS)

1986-11-01

This volume includes the analysis of possible accidents on the RA research reaktor. Any unwanted action causing decrease of integrity of any of the reactor safety barriers is considered to be a reactor accident. Safety barriers are: fuel element cladding, reactor vessel, biogical shield, and reactor building. Reactor accidents can be classified in four categories: (1) accidents caused by reactivity changes; (2) accidents caused by mis function of the cooling system; (3) accidents caused by errors in fuel management and auxiliary systems; (4) accidents caused by natural or other external disasters. The analysis of possible causes of reactor accidents includes the analysis of possible impacts on the reactor itself and the environment [sr

Breakout Session A: Safety Issues. Report from breakout session and discussion on safety issues

International Nuclear Information System (INIS)

Petit, Marc

2013-01-01

The first issue discussed during the breakout session on safety aspects of accident-tolerant fuels was the objective that must be assigned to the development of such concepts. The first goal should be to avoid, or at least limit, the release of radioactive materials into the environment in case of an accident. This implies that severe accidents (core melt) situations must be avoided. To reach this goal, the core geometry must remain coolable, even for accident scenarios worse than what current fuel designs are able to sustain. There was a consensus that the station blackout (SBO) is a good reference transient to evaluate the potential benefits from new, more robust, fuel designs. With respect to the present situation, the merits of new designs can be analysed with respect to three figures: - the 'grace period', i.e. the additional amount of time before the onset of core melt, during which more recovery actions can be made; - the amount of combustible gases produced; - the amount of radioactive materials released. It is important to note that those three values are not independent from one another. They may be understood as three different ways to measure the improvements arising from accident tolerant fuels. The notion of 'grace period' was discussed and it was suggested that it should be compared to the amount of time needed to switch from normal operation to accident management type of procedures. The participants agreed that the 'grace period' should be counted in hours (or even days but the realism of this last goal was questioned). In other words, there was a consensus that a 'grace period' of some minutes is pointless and definitely not worth the effort of developing and characterising the behaviour of new concepts. Although the purpose of accident-tolerant fuel development is to improve the core robustness in design basis accidents (DBA) and situations somewhat beyond like SBO, it was recognised that new concepts must

Status of safety issues at licensed power plants: TMI action plan requirements, unresolved safety issues, generic safety issues

International Nuclear Information System (INIS)

1991-12-01

As part of ongoing US Nuclear Regulatory Commission (NRC) efforts to ensure the quality and accountability of safety issue information, a program was established whereby an annual NUREG report would be published on the status of licensee implementation and NRC verification of safety issues in major NRC requirements areas. This information was compiled and reported in three NUREG volumes. Volume 1, published in March 1991, addressed the status of of Three Mile Island (TMI) Action Plan Requirements. Volume 2, published in May 1991, addressed the status of unresolved safety issues (USIs). Volume 3, published in June 1991, addressed the implementation and verification status of generic safety issues (GSIs). This annual NUREG report combines these volumes into a single report and provides updated information as of September 30, 1991. The data contained in these NUREG reports are a product of the NRC's Safety Issues Management System (SIMS) database, which is maintained by the Project Management Staff in the Office of Nuclear Reactor Regulation and by NRC regional personnel. This report is to provide a comprehensive description of the implementation and verification status of TMI Action Plan Requirements, safety issues designated as USIs, and GSIs that have been resolved and involve implementation of an action or actions by licensees. This report makes the information available to other interested parties, including the public. An additional purpose of this NUREG report is to serve as a follow-on to NUREG-0933, ''A Prioritization of Generic Safety Issues,'' which tracks safety issues up until requirements are approved for imposition at licensed plants or until the NRC issues a request for action by licensees

The Fukushima nuclear accident: insights on the safety aspects

Energy Technology Data Exchange (ETDEWEB)

Thome, Zieli D.; Vellozo, Sergio O., E-mail: zielithome@gmail.com, E-mail: vellozo@cbpf.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Nuclear; Gomes, Rogerio S., E-mail: rogeriog@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Silva, Fernando C., E-mail: fernando@con.ufrj.br [Coordenacao do Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

2013-07-01

The Fukushima nuclear accident has generated doubts and questions which need to be properly understood and addressed. This scientific attitude became necessary to allow the use of the nuclear technology for electricity generation around the world. The nuclear stakeholders are working to obtain these technical answers for the Fukushima questions. We believe that, such challenges will be, certainly, implemented in the next reactor generation, following the technological evolution. The purpose of this work is to perform a critical analysis of the Fukushima nuclear accident, focusing at the common cause failures produced by tsunami, as well as an analysis of the main redundant systems. This work also assesses the mitigative procedures and the subsequent consequences of such actions, which gave results below expectations to avoid the progression of the accident, discussing the concept of sharing of structures, systems and components at multi-unit nuclear power plants, and its eventual inappropriate use in safety-related devices which can compromise the nuclear safety, as well as its consequent impact on the Fukushima accident scenario. The lessons from Fukushima must be better learned, aiming the development of new procedures and new safety systems. Thus, the nuclear technology could reach a higher evolution level in its safety requirements. This knowledge will establish a conceptual milestone in the safety system design, becoming necessary the review of the current acceptance criteria of safety-related systems. (author)

The Fukushima nuclear accident: insights on the safety aspects

International Nuclear Information System (INIS)

Thome, Zieli D.; Vellozo, Sergio O.; Silva, Fernando C.

2013-01-01

The Fukushima nuclear accident has generated doubts and questions which need to be properly understood and addressed. This scientific attitude became necessary to allow the use of the nuclear technology for electricity generation around the world. The nuclear stakeholders are working to obtain these technical answers for the Fukushima questions. We believe that, such challenges will be, certainly, implemented in the next reactor generation, following the technological evolution. The purpose of this work is to perform a critical analysis of the Fukushima nuclear accident, focusing at the common cause failures produced by tsunami, as well as an analysis of the main redundant systems. This work also assesses the mitigative procedures and the subsequent consequences of such actions, which gave results below expectations to avoid the progression of the accident, discussing the concept of sharing of structures, systems and components at multi-unit nuclear power plants, and its eventual inappropriate use in safety-related devices which can compromise the nuclear safety, as well as its consequent impact on the Fukushima accident scenario. The lessons from Fukushima must be better learned, aiming the development of new procedures and new safety systems. Thus, the nuclear technology could reach a higher evolution level in its safety requirements. This knowledge will establish a conceptual milestone in the safety system design, becoming necessary the review of the current acceptance criteria of safety-related systems. (author)

Organizational safety climate and supervisor safety enforcement: Multilevel explorations of the causes of accident underreporting.

Science.gov (United States)

Probst, Tahira M

2015-11-01

According to national surveillance statistics, over 3 million employees are injured each year; yet, research indicates that these may be substantial underestimates of the true prevalence. The purpose of the current project was to empirically test the hypothesis that organizational safety climate and transactional supervisor safety leadership would predict the extent to which accidents go unreported by employees. Using hierarchical linear modeling and survey data collected from 1,238 employees in 33 organizations, employee-level supervisor safety enforcement behaviors (and to a less consistent extent, organizational-level safety climate) predicted employee accident underreporting. There was also a significant cross-level interaction, such that the effect of supervisor enforcement on underreporting was attenuated in organizations with a positive safety climate. These results may benefit human resources and safety professionals by pinpointing methods of increasing the accuracy of accident reporting, reducing actual safety incidents, and reducing the costs to individuals and organizations that result from underreporting. (c) 2015 APA, all rights reserved).

IAEA activities on communication of nuclear safety issues

International Nuclear Information System (INIS)

Wieland, P.

2001-01-01

The regulatory authorities in several countries have taken the initiative to overcome the renowned difficulties of communicating nuclear safety issues. They communicate with segments of the public specially in case of nuclear/radiological accidents, waste disposal, transport of radioactive material or food irradiation. This reflects the full recognition of the importance of the topic. However it is also recognized that there is hitherto a need of international assistance in order to develop a regulatory communication strategy that could be harmonized and at the same time customized to the different needs. Communications on nuclear, radiation, transport and radioactive waste safety are needed to: disseminate information on safety to the public in both routine and emergency situations ; be attentive to public concerns, and address them; maintain social trust and confidence by keeping society informed on the established safety standards and how they are enforced; facilitate the decision-making process on nuclear matters by promptly presenting factual information in a clear manner; integrate and maintain an information network at both the national and international levels; improve co-operation with other countries and international organizations; encourage the dissemination of factual information on nuclear issues in schools. A major factor in addressing all of these questions is understanding the audience(s). A two way communication process is needed to establish what particular audiences want to know and in what form they prefer to receive information. This will differ depending on the audience and circumstances. For example, the information on a routine day-to-day basis will be different from what might be needed at the time of an accident. Communication with the news media is a matter of particular importance, as they are both an audience in themselves and a channel for communicating with wider audiences. (author)

Resolution of Unresolved Safety Issue A-48, ''Hydrogen control measures and effects of hydrogen burns on safety equipment''

International Nuclear Information System (INIS)

Ferrell, C.M.; Soffer, L.

1989-09-01

Unresolved Safety Issue (USI) A-48 arose as a result of the large amount of hydrogen generated and burned within containment during the Three Mile Island accident. This issue covers hydrogen control measures for recoverable degraded-core accidents for all boiling-water reactors (BWRs) and those pressurized-water reactors (PWRs) with ice-condenser containments. The Commission and the nuclear industry have sponsored extensive research in this area, which has led to significant revision of the Commission's hydrogen control regulations, given in Title 10, Code of Federal Regulations, Part 50 (10 CFR 50), Section 50.44. BWRs having Mark I and II containments are presently required to operate with inerted containment atmospheres that effectively prevent hydrogen combustion. BWRs with Mark III containments and PWRs with ice-condenser containments are now required to be equipped with hydrogen control systems to protect containment integrity and safety systems inside containment. Industry has chosen to use hydrogen igniter systems to burn hydrogen produced in a controlled fashion to prevent damage. An independent review by a Committee of the National Research Council concluded that, for most accident scenarios, current regulatory requirements make it highly unlikely that hydrogen detonation would be the cause of containment failure. On the basis of the extensive research effort conducted and current regulatory requirements, including their implementation, the staff concludes that no new regulatory guidance on hydrogen control for recoverable degraded-core accidents for these types of plants is necessary and that USI A-48 is resolved

Analysis on Dangerous Source of Large Safety Accident in Storage Tank Area

Science.gov (United States)

Wang, Tong; Li, Ying; Xie, Tiansheng; Liu, Yu; Zhu, Xueyuan

2018-01-01

The difference between a large safety accident and a general accident is that the consequences of a large safety accident are particularly serious. To study the tank area which factors directly or indirectly lead to the occurrence of large-sized safety accidents. According to the three kinds of hazard source theory and the consequence cause analysis of the super safety accident, this paper analyzes the dangerous source of the super safety accident in the tank area from four aspects, such as energy source, large-sized safety accident reason, management missing, environmental impact Based on the analysis of three kinds of hazard sources and environmental analysis to derive the main risk factors and the AHP evaluation model is established, and after rigorous and scientific calculation, the weights of the related factors in four kinds of risk factors and each type of risk factors are obtained. The result of analytic hierarchy process shows that management reasons is the most important one, and then the environmental factors and the direct cause and Energy source. It should be noted that although the direct cause is relatively low overall importance, the direct cause of Failure of emergency measures and Failure of prevention and control facilities in greater weight.

Active and passive vehicle safety at Volkswagen accident research

Energy Technology Data Exchange (ETDEWEB)

Jungmichel, M.; Stanzel, M.; Zobel, R. [Volkswagen AG, Wolfsburg (Germany)

2001-07-01

Accident Analysis is an efficient means of improving vehicle passive safety and is used frequently and intensively. However, reliable data on accident causation is much more difficult to obtain. In most cases, one or more of the persons involved in an accident will face litigation and therefore are reluctant to provide the information that is essential to researchers. In addition, antilock brakes in almost every current vehicle have caused certain characteristic evidence, i.e. skid marks, to appear much less frequently than before. However, this evidence provides valuable information for assessing the reaction of the driver and his attempt to avoid the accident. In order to implement strategies of accident avoidance, accident causation must first be fully understood. Therefore, one of the assignments of the Volkswagen Accident Research Unit is to interpret global statistics, as well as to study single cases in order to come up with strategies for collision avoidance or mitigation. Currently, our primary concern is focused on active vehicle safety by researching vehicle behavior in the pre-crash phase. (orig.)

For improvements of issues behind food safety regulations implemented following the Fukushima nuclear accident

International Nuclear Information System (INIS)

Hamada, Nobuyuki; Ogino, Haruyuki

2011-01-01

The great quake and a subsequent tsunami seriously damaged the Fukushima nuclear power plants on 11 March 2011, followed by radionuclide releases outside the crippled reactors. Regulatory limits stipulated as 'provisional regulation values' were set to minimize internal exposure via ingestion of contaminated food and drink. Tap water, raw milk, vegetables, seafood and tea exceeded the limit, and distribution and/or consumption of these stuffs were temporality restricted. It took 7 and 11 days to set the provisional regulation values and to order the first restriction after the declaration of nuclear emergency situations, respectively. All restrictions began within 25 days after the first excess in each item, but the commencement of restrictions was concomitant with the social dislocations. All restrictions for tap water were withdrawn within 51 days, but restrictions for food have yet to be lifted. Among all items, maximum levels were detected in leafy vegetables (54,100 Bq/kg of 131 I, 82,000 Bq/kg of 134 Cs and 137 Cs). Most provisional regulation values were adopted from the preexisting 'index values'. Index values were logically designed and practically convenient. However, food and radionuclides were not comprehensively covered, and the same value was given to emergency and existing exposure situations. Also, different provisional regulation values were set for infants and others. In this respect, we here propose the concept of the 'graded triphasic reference level system' to optimize food safety regulations in early, intermediate and late phases following the accident, where each example phase-specific reference level value is provided. This paper focuses on the logic and issues behind such food safety regulations. The food monitoring data of 24,685 samples and the enforced restrictions shall also be outlined predicated on the information available as of 12 June 2011. (author)

Research investigation report on Fukushima Daiichi nuclear accident

International Nuclear Information System (INIS)

2012-03-01

This report was issued in February 2012 by Rebuild Japan Initiative Foundation's Independent Investigation Commission on the Fukushima Daiichi Nuclear Accident, which consisted of six members from the private sector in independent positions and with no direct interest in the business of promoting nuclear power. Commission aimed to determine the truth behind the accident by clarifying the various problems and reveal systematic problems behind these issues so as to create a new starting point by identifying clear lessons learned. Report composed of four chapters; (1) progression of Fukushima accident and resulting damage (accident management after Fukushima accident, and effects and countermeasure of radioactive materials discharged into the environment), (2) response against Fukushima accident (emergency response of cabinet office against nuclear disaster, risk communication and on-site response against nuclear disaster), (3) analysis of historical and structural factors (technical philosophy of nuclear safety, problems of nuclear safety regulation of Fukushima accident, safety regulatory governance and social background of 'Safety Myth'), (4) Global Context (implication in nuclear security, Japan in nuclear safety regime, U.S.-Japan relations for response against Fukushima accident, lessons learned from Fukushima accident - aiming at creation of resilience). Report could identify causes of Fukushima accident and factors related to resulting damages, show the realities behind failure to prevent the spread of damage, and analyze the overall structural and historical background behind the accidents. (T. Tanaka)

FUKUSHIMA DAI-ICHI ACCIDENT: LESSONS LEARNED AND FUTURE ACTIONS FROM THE RISK PERSPECTIVES

Directory of Open Access Journals (Sweden)

JOON-EON YANG

2014-02-01

Full Text Available The Fukushima Dai-Ichi accident in 2011 has affected various aspects of the nuclear society worldwide. The accident revealed some problems in the conventional approaches used to ensure the safety of nuclear installations. To prevent such disastrous accidents in the future, we have to learn from them and improve the conventional approaches in a more systematic manner. In this paper, we will cover three issues. The first is to identify the key issues that affected the progress of the Fukushima Dai-Ichi accident greatly. We examine the accident from a defense-in-depth point of view to identify such issues. The second is to develop a more systematic approach to enhance the safety of nuclear installations. We reexamine nuclear safety from a risk point of view. We use the concepts of residual and unknown risks in classifying the risk space. All possible accident scenarios types are reviewed to clarify the characteristics of the identified issues. An approach is proposed to improve our conventional approaches used to ensure nuclear safety including the design of safety features and the safety assessments from a risk point of view. Finally, we address some issues to be improved in the conventional risk assessment and management framework and/or practices to enhance nuclear safety.

Fukushima Dai-Ichi accident: Lessons Learned and Future Actions from the Risk Perspectives

Energy Technology Data Exchange (ETDEWEB)

Yang, Jooneon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-02-15

The Fukushima Dai-Ichi accident in 2011 has affected various aspects of the nuclear society worldwide. The accident revealed some problems in the conventional approaches used to ensure the safety of nuclear installations. To prevent such disastrous accidents in the future, we have to learn from them and improve the conventional approaches in a more systematic manner. In this paper, we will cover three issues. The first is to identify the key issues that affected the progress of the Fukushima Dai-Ichi accident greatly. We examine the accident from a defense-in-depth point of view to identify such issues. The second is to develop a more systematic approach to enhance the safety of nuclear installations. We reexamine nuclear safety from a risk point of view. We use the concepts of residual and unknown risks in classifying the risk space. All possible accident scenarios types are reviewed to clarify the characteristics of the identified issues. An approach is proposed to improve our conventional approaches used to ensure nuclear safety including the design of safety features and the safety assessments from a risk point of view. Finally, we address some issues to be improved in the conventional risk assessment and management framework and/or practices to enhance nuclear safety.

From learning from accidents to teaching about accident causation and prevention: Multidisciplinary education and safety literacy for all engineering students

International Nuclear Information System (INIS)

Saleh, Joseph H.; Pendley, Cynthia C.

2012-01-01

In this work, we argue that system accident literacy and safety competence should be an essential part of the intellectual toolkit of all engineering students. We discuss why such competence should be taught and nurtured in engineering students, and provide one example for how this can be done. We first define the class of adverse events of interest as system accidents, distinct from occupational accidents, through their (1) temporal depth of causality and (2) diversity of agency or groups and individuals who influence or contribute to the accident occurrence/prevention. We then address the question of why the interest in this class of events and their prevention, and we expand on the importance of system safety literacy and the contributions that engineering students can make in the long-term towards accident prevention. Finally, we offer one model for an introductory course on accident causation and system safety, discuss the course logistics, material and delivery, and our experience teaching this subject. The course starts with the anatomy of accidents and is grounded in various case studies; these help illustrate the multidisciplinary nature of the subject, and provide the students with the important concepts to describe the phenomenology of accidents (e.g., initiating events, accident precursor or lead indicator, and accident pathogen). More importantly, the case studies invite a deep reflection on the underlying failure mechanisms, their generalizability, and the various safety levers for accident prevention. The course then proceeds to an exposition of defense-in-depth, safety barriers and principles, essential elements for an education in accident prevention, and it concludes with a presentation of basic concepts and tools for uncertainty and risk analysis. Educators will recognize the difficulties in designing a new course on such a broad subject. It is hoped that this work will invite comments and contributions from the readers, and that the journal will

Jules Horowitz reactor - Complementary safety assessment in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Jules Horowitz reactor (RJH) to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. RJH is being built on the Cadarache CEA's site. Robustness is the ability for the facility to withstand events beyond the level for which the facility was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence (cliff edge effect). Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like RJH's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. This report is divided into 9 main chapters: 1) main features of the RJH facility, 2) identification of cliff edge risks and of equipment essential for safety, 3) earthquake risk, 4) flood risk, 5) risks due to other extreme natural disasters, 6) the loss of electrical power supplies and of cooling systems, 7) management of severe accidents, 8) subcontracting policy, 9) synthesis and list of improvements. This study shows a globally good robustness of the RJH for the considered risks. Nevertheless it can considered relevant to increase the robustness of the plant on a few points: -) to increase the seismic safety margins of some pieces of equipment, -) to increase the robustness of the internal electrical power supplies, -) to increase the fuel cooling capacity, and -) to improve the management of the post-accidental period. (A.C.)

Plant safety review from mass criticality accident

International Nuclear Information System (INIS)

Susanto, B.G.

2000-01-01

The review has been done to understand the resent status of the plant in facing postulated mass criticality accident. From the design concept of the plant all the components in the system including functional groups have been designed based on favorable mass/geometry safety principle. The criticality safety for each component is guaranteed because all the dimensions relevant to criticality of the components are smaller than dimensions of 'favorable mass/geometry'. The procedures covering all aspects affecting quality including the safety related are developed and adhered to at all times. Staff are indoctrinated periodically in short training session to warn the important of the safety in process of production. The plant is fully equipped with 6 (six) criticality detectors in strategic places to alert employees whenever the postulated mass criticality accident occur. In the event of Nuclear Emergency Preparedness, PT BATAN TEKNOLOGI has also proposed the organization structure how promptly to report the crisis to Nuclear Energy Control Board (BAPETEN) Indonesia. (author)

Outline of the Fukushima Daiichi Accident. Lessons Learned and Safety Enhancements

Science.gov (United States)

Hirano, Masashi

2017-09-01

Nuclear Regulation Authority (NRA) was established on September 19, 2012. The NRA very urgently developed and issued the new regulatory requirements on July 8, 2014, taking into the account the lessons learned from the accident. It is noted that the NRA issued the Statement of Nuclear Safety Culture on May 27, 2015 which clearly expressed the NRA's commitment to break with the safety myth. This paper briefly presents the outline of the Fukushima Daiichi accident and summarizes the major lessons learned having been drawn and safety enhancements having been done in Japan for the purpose of giving inputs to the discussions to be taken place in the Special Invited Session "Fukushima, 5 years after".

Regulation Plans on Severe Accidents developed by KINS Severe Accident Regulation Preparation TFT

International Nuclear Information System (INIS)

Kim, Kyun Tae; Chung, Ku Young; Na, Han Bee

2016-01-01

Some nuclear power plants in Fukushima Daiichi site had lost their emergency reactor cooling function for long-time so the fuels inside the reactors were molten, and the integrity of containment was damaged. Therefore, large amount of radioactive material was released to environment. Because the social and economic effects of severe accidents are enormous, Korean Government already issued 'Severe Accident Policy' in 2001 which requires nuclear power plant operators to set up 'Quantitative Safety Goal', to do 'Probabilistic Safety Analysis', to install 'Severe Accident Countermeasures' and to make 'Severe Accident Management Plan'. After the Fukushima disaster, a Special Safety Inspection was performed for all operating nuclear power plants of Korea. The inspection team from industry, academia, and research institutes assessed Korean NPPs capabilities to cope with or respond to severe accidents and emergency situation caused by natural disasters such as a large earthquake or tsunami. As a result of the special inspection, about 50 action items were identified to increase the capability to cope with natural disaster and severe accidents. Nuclear Safety Act has been amended to require NPP operators to submit Accident Management Plant as part of operating license application. The KINS Severe Accident Regulation Preparation TFT had first investigated oversea severe accident regulation trend before and after the Fukushima accident. Then, the TFT has developed regulation draft for severe accidents such as Severe accident Management Plans, the required design features for new NPPs to prevent severe accident against multiple failures and beyond-design external events, countermeasures to mitigate severe accident and to keep the integrity of containment, and assessment methodology on safety assessment plan and probabilistic safety assessment

The Fukushima Dai-ichi Accident and its implications for the safety of nuclear power

Science.gov (United States)

Barletta, William

2016-05-01

Five years ago the dramatic events in Fukushima that followed the massive earthquake and subsequent tsunami that struck Japan on March 11, 2011 sharpened the focus of scientists, engineers and general public on the broad range of technical, environmental and societal issues involved in assuring the safety of the world's nuclear power complex. They also called into question the potential of nuclear power to provide a growing, sustainable resource of CO2-free energy. The issues raised by Fukushima Dai-ichi have provoked urgent concern, not only because of the potential harm that could result from severe accidents or from intentional damage to nuclear reactors or to facilities involved in the nuclear fuel cycle, but also because of the extensive economic impact of those accidents and of the measures taken to avoid them.

Status of safety issues at licensed power plants: TMI Action Plan requirements; unresolved safety issues; generic safety issues; other multiplant action issues

International Nuclear Information System (INIS)

1993-12-01

As part of ongoing US Nuclear Regulatory Commission (NRC) efforts to ensure the quality and accountability of safety issue information, the NRC established a program for publishing an annual report on the status of licensee implementation and NRC verification of safety issues in major NRC requirements areas. This information was initially compiled and reported in three NUREG-series volumes. Volume 1, published in March 1991, addressed the status of Three Mile Island (TMI) Action Plan Requirements. Volume 2, published in May 1991, addressed the status of unresolved safety issues (USIs). Volume 3, published in June 1991, addressed the implementation and verification status of generic safety issues (GSIs). The first annual supplement, which combined these volumes into a single report and presented updated information as of September 30, 1991, was published in December 1991. The second annual supplement, which provided updated information as of September 30, 1992, was published in December 1992. Supplement 2 also provided the status of licensee implementation and NRC verification of other multiplant action (MPA) issues not related to TMI Action Plan requirements, USIs, or GSIs. This third annual NUREG report, Supplement 3, presents updated information as of September 30, 1993. This report gives a comprehensive description of the implementation and verification status of TMI Action Plan requirements, safety issues designated as USIs, GSIs, and other MPAs that have been resolved and involve implementation of an action or actions by licensees. This report makes the information available to other interested parties, including the public. Additionally, this report serves as a follow-on to NUREG-0933, ''A Prioritization of Generic Safety Issues,'' which tracks safety issues until requirements are approved for imposition at licensed plants or until the NRC issues a request for action by licensees

Unions, Health and Safety Committees, and Workplace Accidents in the Korean Manufacturing Sector

Directory of Open Access Journals (Sweden)

Woo-Yung Kim

2016-06-01

Conclusion: Health and safety committees were found to reduce the incidence of accidents whereas unionized establishments have higher incidence of accidents than nonunionized establishments. We also found that health and safety committees can more effectively reduce accidents in nonunionized establishments. By contrast, nonexclusive joint committees can more effectively reduce accidents in unionized establishments.

Accomplishments and challenges of the severe accident research

International Nuclear Information System (INIS)

Sehgal, B.R.

2001-01-01

This paper briefly describes the progress of the severe accident research since 1980, in terms of the accomplishments made so far and the challenges that remain. Much has been accomplished: many important safety issues have been resolved and consensus is near on some others. However, some of the previously identified safety issues remain as challenges, while some new ones have arisen due to the shift in focus from containment to vessel integrity. New reactor designs have also created some new challenges. In general, the regulatory demands for new reactor designs are stricter, thereby requiring much greater attention to the safety issues concerned with the containment design of the new large reactors, and to the accident management procedures for mitigating the consequences of a severe accident. We apologize for not providing references to many fine investigations that contributed to the great progress made so far in the severe accident research

The issue of safety in the transports of radioactive materials

International Nuclear Information System (INIS)

Pallier, Lucien

1961-01-01

This report addresses and discusses the various hazards associated with transports of radioactive materials, their prevention, intervention measures, and precautions to be taken by rescuers, notably how these issues are addressed in regulations. For each of these issues, this report proposes guidelines, good practices, or procedures to handle the situation. The author first addresses hazards related to a transport of radioactive products: multiplicity of hazards, different hazards due to radioactivity, hazards due to transport modes, scale of dangerous doses. The second part addresses precautionary measures: for road transports, for air transports, for maritime transports, control procedures. The third part addresses the intervention in case of accident: case of a road accident with an unhurt or not vehicle crew, role of the first official rescuers, other kinds of accidents. The fourth part briefly addresses the case of transport of fissile materials. The fifth part discusses the implications of safety measures. Appendices indicate standards, and give guidelines for the construction of a storage building for radioactive products, for the control and storage of parcels containing radioactive products, and for the establishment of instructions for the first aid personnel

Experimental investigations relevant for hydrogen and fission product issues raised by the Fukushima accident

Directory of Open Access Journals (Sweden)

Sanjeev Gupta

2015-02-01

Full Text Available The accident at Japan's Fukushima Daiichi nuclear power plant in March 2011, caused by an earthquake and a subsequent tsunami, resulted in a failure of the power systems that are needed to cool the reactors at the plant. The accident progression in the absence of heat removal systems caused Units 1-3 to undergo fuel melting. Containment pressurization and hydrogen explosions ultimately resulted in the escape of radioactivity from reactor containments into the atmosphere and ocean. Problems in containment venting operation, leakage from primary containment boundary to the reactor building, improper functioning of standby gas treatment system (SGTS, unmitigated hydrogen accumulation in the reactor building were identified as some of the reasons those added-up in the severity of the accident. The Fukushima accident not only initiated worldwide demand for installation of adequate control and mitigation measures to minimize the potential source term to the environment but also advocated assessment of the existing mitigation systems performance behavior under a wide range of postulated accident scenarios. The uncertainty in estimating the released fraction of the radionuclides due to the Fukushima accident also underlined the need for comprehensive understanding of fission product behavior as a function of the thermal hydraulic conditions and the type of gaseous, aqueous, and solid materials available for interaction, e.g., gas components, decontamination paint, aerosols, and water pools. In the light of the Fukushima accident, additional experimental needs identified for hydrogen and fission product issues need to be investigated in an integrated and optimized way. Additionally, as more and more passive safety systems, such as passive autocatalytic recombiners and filtered containment venting systems are being retrofitted in current reactors and also planned for future reactors, identified hydrogen and fission product issues will need to be coupled

Regulation Plans on Severe Accidents developed by KINS Severe Accident Regulation Preparation TFT

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyun Tae; Chung, Ku Young; Na, Han Bee [KINS, Daejeon (Korea, Republic of)

2016-05-15

Some nuclear power plants in Fukushima Daiichi site had lost their emergency reactor cooling function for long-time so the fuels inside the reactors were molten, and the integrity of containment was damaged. Therefore, large amount of radioactive material was released to environment. Because the social and economic effects of severe accidents are enormous, Korean Government already issued 'Severe Accident Policy' in 2001 which requires nuclear power plant operators to set up 'Quantitative Safety Goal', to do 'Probabilistic Safety Analysis', to install 'Severe Accident Countermeasures' and to make 'Severe Accident Management Plan'. After the Fukushima disaster, a Special Safety Inspection was performed for all operating nuclear power plants of Korea. The inspection team from industry, academia, and research institutes assessed Korean NPPs capabilities to cope with or respond to severe accidents and emergency situation caused by natural disasters such as a large earthquake or tsunami. As a result of the special inspection, about 50 action items were identified to increase the capability to cope with natural disaster and severe accidents. Nuclear Safety Act has been amended to require NPP operators to submit Accident Management Plant as part of operating license application. The KINS Severe Accident Regulation Preparation TFT had first investigated oversea severe accident regulation trend before and after the Fukushima accident. Then, the TFT has developed regulation draft for severe accidents such as Severe accident Management Plans, the required design features for new NPPs to prevent severe accident against multiple failures and beyond-design external events, countermeasures to mitigate severe accident and to keep the integrity of containment, and assessment methodology on safety assessment plan and probabilistic safety assessment.

Nuclear accidents

International Nuclear Information System (INIS)

1987-01-01

On 27 May 1986 the Norwegian government appointed an inter-ministerial committee of senior officials to prepare a report on experiences in connection with the Chernobyl accident. The present second part of the committee's report describes proposals for measures to prevent and deal with similar accidents in the future. The committee's evaluations and proposals are grouped into four main sections: Safety and risk at nuclear power plants; the Norwegian contingency organization for dealing with nuclear accidents; compensation issues; and international cooperation

Development of the methodology and approaches to validate safety and accident management

International Nuclear Information System (INIS)

Asmolov, V.G.

1997-01-01

The article compares the development of the methodology and approaches to validate the nuclear power plant safety and accident management in Russia and advanced industrial countries. It demonstrates that the development of methods of safety validation is dialectically related to the accumulation of the knowledge base on processes and events during NPP normal operation, transients and emergencies, including severe accidents. The article describes the Russian severe accident research program (1987-1996), the implementation of which allowed Russia to reach the world level of the safety validation efforts, presents future high-priority study areas. Problems related to possible approaches to the methodological accident management development are discussed. (orig.)

The relationships between OHS prevention costs, safety performance, employee satisfaction and accident costs.

Science.gov (United States)

Bayram, Metin; Ünğan, Mustafa C; Ardıç, Kadir

2017-06-01

Little is known about the costs of safety. A literature review conducted for this study indicates there is a lack of survey-based research dealing with the effects of occupational health and safety (OHS) prevention costs. To close this gap in the literature, this study investigates the interwoven relationships between OHS prevention costs, employee satisfaction, OHS performance and accident costs. Data were collected from 159 OHS management system 18001-certified firms operating in Turkey and analyzed through structural equation modeling. The findings indicate that OHS prevention costs have a significant positive effect on safety performance, employee satisfaction and accident costs savings; employee satisfaction has a significant positive effect on accident costs savings; and occupational safety performance has a significant positive effect on employee satisfaction and accident costs savings. Also, the results indicate that safety performance and employee satisfaction leverage the relationship between prevention costs and accident costs.

Nuclear accidents and safety measures of domestic nuclear power plants

International Nuclear Information System (INIS)

Song Zurong; Che Shuwei; Pan Xiang

2012-01-01

Based on the design standards for the safety of nuclear and radiation in nuclear power plants, the three accidents in the history of nuclear power are analyzed. And the main factors for these accidents are found out, that is, human factors and unpredicted natural calamity. By combining the design and operation parameters of domestic nuclear plants, the same accidents are studied and some necessary preventive schemes are put forward. In the security operation technology of domestic nuclear power plants nowadays, accidents caused by human factors can by prevented completely. But the safety standards have to be reconsidered for the unpredicted neutral disasters. How to reduce the hazard of nuclear radiation and leakage to the level that can be accepted by the government and public when accidents occur under extreme conditions during construction and operation of nuclear power plants must be considered adequately. (authors)

Incorporation of advanced accident analysis methodology into safety analysis reports

International Nuclear Information System (INIS)

2003-05-01

The IAEA Safety Guide on Safety Assessment and Verification defines that the aim of the safety analysis should be by means of appropriate analytical tools to establish and confirm the design basis for the items important to safety, and to ensure that the overall plant design is capable of meeting the prescribed and acceptable limits for radiation doses and releases for each plant condition category. Practical guidance on how to perform accident analyses of nuclear power plants (NPPs) is provided by the IAEA Safety Report on Accident Analysis for Nuclear Power Plants. The safety analyses are performed both in the form of deterministic and probabilistic analyses for NPPs. It is customary to refer to deterministic safety analyses as accident analyses. This report discusses the aspects of using the advanced accident analysis methods to carry out accident analyses in order to introduce them into the Safety Analysis Reports (SARs). In relation to the SAR, purposes of deterministic safety analysis can be further specified as (1) to demonstrate compliance with specific regulatory acceptance criteria; (2) to complement other analyses and evaluations in defining a complete set of design and operating requirements; (3) to identify and quantify limiting safety system set points and limiting conditions for operation to be used in the NPP limits and conditions; (4) to justify appropriateness of the technical solutions employed in the fulfillment of predetermined safety requirements. The essential parts of accident analyses are performed by applying sophisticated computer code packages, which have been specifically developed for this purpose. These code packages include mainly thermal-hydraulic system codes and reactor dynamics codes meant for the transient and accident analyses. There are also specific codes such as those for the containment thermal-hydraulics, for the radiological consequences and for severe accident analyses. In some cases, codes of a more general nature such

CANDU safety under severe accidents

International Nuclear Information System (INIS)

Snell, V.G.; Howieson, J.Q.; Frescura, G.M.; King, F.; Rogers, J.T.; Tamm, H.

1988-01-01

The characteristics of the CANDU reactor relevant to severe accidents are set first by the inherent properties of the design, and second by the Canadian safety/licensing approach. Probabilistic safety assessment studies have been performed on operating CANDU plants, and on the 4 x 880 MW(e) Darlington station now under construction; furthermore a scoping risk assessment has been done for a CANDU 600 plant. They indicate that the summed severe core damage frequency is of the order of 5 x 10 -6 /year. CANDU nuclear plant designers and owner/operators share information and operational experience nationally and internationally through the CANDU Owners' Group (COG). The research program generally emphasizes the unique aspects of the CANDU concept, such as heat removal through the moderator, but it has also contributed significantly to areas generic to most power reactors such as hydrogen combustion, containment failure modes, fission product chemistry, and high temperature fuel behaviour. Abnormal plant operating procedures are aimed at first using event-specific emergency operating procedures, in cases where the event can be diagnosed. If this is not possible, generic procedures are followed to control Critical Safety Parameters and manage the accident. Similarly, the on-site contingency plans include a generic plan covering overall plant response strategy, and a specific plan covering each category of contingency

Enhanced safety features of CHASHMA NPP UNIT-2 to encounter selected severe accidents, various challenges involved to prove the adequacy of severe accidents prevention/mitigation measures and to write management guidelines with one possible solution to these challenges

International Nuclear Information System (INIS)

Iqbal, Z.; Minhaj, A.

2007-01-01

This paper describes enhanced safety features of Chashma Nuclear Power Plant Unit-2 (C-2), a 325 MWe PWR to encounter selected severe accidents and discusses various challenges involved to prove the adequacy of severe accidents encountering measures and to write severe accident management guidelines (SAMGs) in compliance with the recently introduced national regulations based on the new IAEA nuclear safety standards. C-2 is being built by China National Nuclear Corporation (CNNC) for Pakistan Atomic Energy Commission (PAEC). Its twin, Unit-1 (C-1) also a 325 MWe PWR, was commissioned in 2000. Nuclear power safety with reference to severe accidents should be treated as a global issue and therefore the developed countries should include the people of developing countries in nuclear power industry's various severe accidents based research and development programs. The implementation of this idea may also deliver few other useful and mutually beneficial byproducts. (author)

Major accident prevention through applying safety knowledge management approach.

Science.gov (United States)

Kalatpour, Omid

2016-01-01

Many scattered resources of knowledge are available to use for chemical accident prevention purposes. The common approach to management process safety, including using databases and referring to the available knowledge has some drawbacks. The main goal of this article was to devise a new emerged knowledge base (KB) for the chemical accident prevention domain. The scattered sources of safety knowledge were identified and scanned. Then, the collected knowledge was formalized through a computerized program. The Protégé software was used to formalize and represent the stored safety knowledge. The domain knowledge retrieved as well as data and information. This optimized approach improved safety and health knowledge management (KM) process and resolved some typical problems in the KM process. Upgrading the traditional resources of safety databases into the KBs can improve the interaction between the users and knowledge repository.

Problems of probabilistic safety assessment after Fukushima Daiichi nuclear power plant accident

International Nuclear Information System (INIS)

Sugiyama, Naoki

2011-01-01

Probabilistic safety assessment (PSA) methodology to assure nuclear safety is had great expectations of lessons learned from Fukushima Daiichi nuclear power plant (NPP) accident and on the other hand this accident made actualized technical problems of PSA. Effectiveness of current PSA methodology for risk assessment was confirmed by comparing the accident development with accident scenario of PSA and equipment failure rate. From a viewpoint of nuclear safety objective and defense in depth approach of IAEA, technical problems of PSA were (1) extension of PSA for spent fuel pool and waste disposal system as well as level 3PSA for broader environmental contamination and (2) overlapping of accident scenario of plural unit site, balance of high quality plant management and preceding negation, treatment of uncertainty of external events, severe accident measure and human reliability analysis and reflection of disaster prevention capability to level 3PSA. In order to upgrade PSA technology, six proposals were described for nuclear safety and defense in depth, comprehensive evaluation scope and catch-up of latest technology, necessity of strategic preparation of PSA standard, human resources fostering and risk communication. (T. Tanaka)

Accident management insights after the Fukushima Daiichi NPP accident

International Nuclear Information System (INIS)

Degueldre, Didier; Viktorov, Alexandre; Tuomainen, Minna; Ducamp, Francois; Chevalier, Sophie; Guigueno, Yves; Tasset, Daniel; Heinrich, Marcus; Schneider, Matthias; Funahashi, Toshihiro; Hotta, Akitoshi; Kajimoto, Mitsuhiro; Chung, Dae-Wook; Kuriene, Laima; Kozlova, Nadezhda; Zivko, Tomi; Aleza, Santiago; Jones, John; McHale, Jack; Nieh, Ho; Pascal, Ghislain; ); Nakoski, John; Neretin, Victor; Nezuka, Takayoshi; )

2014-01-01

The Fukushima Daiichi nuclear power plant (NPP) accident, that took place on 11 March 2011, initiated a significant number of activities at the national and international levels to reassess the safety of existing NPPs, evaluate the sufficiency of technical means and administrative measures available for emergency response, and develop recommendations for increasing the robustness of NPPs to withstand extreme external events and beyond design basis accidents. The OECD Nuclear Energy Agency (NEA) is working closely with its member and partner countries to examine the causes of the accident and to identify lessons learnt with a view to the appropriate follow-up actions to be taken by the nuclear safety community. Accident management is a priority area of work for the NEA to address lessons being learnt from the accident at the Fukushima Daiichi NPP following the recommendations of Committee on Nuclear Regulatory Activities (CNRA), Committee on the Safety of Nuclear Installations (CSNI), and Committee on Radiation Protection and Public Health (CRPPH). Considering the importance of these issues, the CNRA authorised the formation of a task group on accident management (TGAM) in June 2012 to review the regulatory framework for accident management following the Fukushima Daiichi NPP accident. The task group was requested to assess the NEA member countries needs and challenges in light of the accident from a regulatory point of view. The general objectives of the TGAM review were to consider: - enhancements of on-site accident management procedures and guidelines based on lessons learnt from the Fukushima Daiichi NPP accident; - decision-making and guiding principles in emergency situations; - guidance for instrumentation, equipment and supplies for addressing long-term aspects of accident management; - guidance and implementation when taking extreme measures for accident management. The report is built on the existing bases for capabilities to respond to design basis

Status of safety issues at licensed power plants: TMI Action Plan requirements, unresolved safety issues, generic safety issues, other multiplant action issues. Supplement 4

International Nuclear Information System (INIS)

1994-12-01

As part of ongoing US Nuclear Regulatory Commission (NRC) efforts to ensure the quality and accountability of safety issue information, the NRC established a program for publishing an annual report on the status of licensee implementation and NRC verification of safety issues in major NRC requirements areas. This information was initially compiled and reported in three NUREG-series volumes. Volume 1, published in March 1991, addressed the status of Three Mile Island (TMI) Action Plan Requirements. Volume 2, published in May 1991, addressed the status of unresolved safety issues (USIs). Volume 3, published in June 1991, addressed the implementation and verification status of generic safety issues (GSIs). The first annual supplement, which combined these volumes into a single report and presented updated information as of September 30, 1991, was published in December 1991. The second annual supplement, which provided updated information as of September 30, 1992, was published in December 1992. Supplement 2 also provided the status of licensee implementation and NRC verification of other multiplant action (MPA) issues not related to TMI Action Plan requirements, USIs, or GSIs. Supplement 3 gives status as of September 30, 1993. This annual report, Supplement 4, presents updated information as of September 30, 1994. This report gives a comprehensive description of the implementation and verification status of TMI Action Plan requirements, safety issues designated as USIs, GSIs, and other MPAs that have been resolved and involve implementation of an action or actions by licensees. This report makes the information available to other interested parties, including the public. Additionally, this report serves as a follow-on to NUREG-0933, ''A Prioritization of Generic Safety Issues,'' which tracks safety issues until requirements are approved for imposition at licensed plants or until the NRC issues a request for action by licensees

Requirements to amend the main influence factors on the safety culture after fukushima accident

International Nuclear Information System (INIS)

Farcasiu, M.; Nitoi, M.

2015-01-01

The paper presents a general model that provides a framework for the safety culture assessment, creating the possibility to identify factors that can significantly influence the safety culture. The main safety culture influence factors (SCIF) used by model are the following: regulatory environment, organizational environment, worker characteristics, socio-political environment, national culture, organization history, business and technological characteristics. After the analysis of the deficiencies and weaknesses of SCIFc in evolution of the Fukushima accident, some issues that may become necessities and requirements to change and improve both the safety culture and safety of the nuclear installations were highlighted. For each influence factor were identified some requirements to amend. The results will emphasize the necesity of the human - technology - organization system assessment. Hence it was demonstrated that the safety culture results from the interaction of individuals with technology and with the organization. (authors)

Safety issues and updates under MR environments

Energy Technology Data Exchange (ETDEWEB)

Kim, Soo Jung; Kim, Kyung Ah, E-mail: bellenina@daum.net

2017-04-15

Highlights: • Unexpected biological effects can occur within stronger magnetic fields. • MR safety for MR conditional items is not guaranteed beyond the tested conditions. • Updated knowledge about MR-related safety is important for a safe MR environment. - Abstract: Magnetic resonance (MR) imaging is a useful imaging tool with superior soft tissue contrast for diagnostic evaluation. The MR environments poses unique risks to patients and employees differently from ionizing radiation exposure originated from computed tomography and plain x-ray films. The technology associated with MR system has evolved continuously since its introduction in the late 1970s. MR systems have advanced with static magnetic fields, faster and stronger gradient magnetic fields and more powerful radiofrequency transmission coils. Higher field strengths of MR offers greater signal to noise capability and better spatial resolution, resulting in better visualization of anatomic detail, with a reduction in scan time. With the rapid evolution of technology associated with MR, we encounter new MR-related circumstances and unexpected dangerous conditions. A comprehensive update of our knowledge about MR safety is necessary to prevent MR-related accidents and to ensure safety for patients and staff associated with MR. This review presents an overview about MR-related safety issues and updates.

Accident analysis for nuclear power plants

International Nuclear Information System (INIS)

2002-01-01

Deterministic safety analysis (frequently referred to as accident analysis) is an important tool for confirming the adequacy and efficiency of provisions within the defence in depth concept for the safety of nuclear power plants (NPPs). Owing to the close interrelation between accident analysis and safety, an analysis that lacks consistency, is incomplete or is of poor quality is considered a safety issue for a given NPP. Developing IAEA guidance documents for accident analysis is thus an important step towards resolving this issue. Requirements and guidelines pertaining to the scope and content of accident analysis have, in the past, been partially described in various IAEA documents. Several guidelines relevant to WWER and RBMK type reactors have been developed within the IAEA Extrabudgetary Programme on the Safety of WWER and RBMK NPPs. To a certain extent, accident analysis is also covered in several documents of the revised NUSS series, for example, in the Safety Requirements on Safety of Nuclear Power Plants: Design (NS-R-1) and in the Safety Guide on Safety Assessment and Verification for Nuclear Power Plants (NS-G-1.2). Consistent with these documents, the IAEA has developed the present Safety Report on Accident Analysis for Nuclear Power Plants. Many experts have contributed to the development of this Safety Report. Besides several consultants meetings, comments were collected from more than fifty selected organizations. The report was also reviewed at the IAEA Technical Committee Meeting on Accident Analysis held in Vienna from 30 August to 3 September 1999. The present IAEA Safety Report is aimed at providing practical guidance for performing accident analyses. The guidance is based on present good practice worldwide. The report covers all the steps required to perform accident analyses, i.e. selection of initiating events and acceptance criteria, selection of computer codes and modelling assumptions, preparation of input data and presentation of the

Nuclear safety - Topical issues

International Nuclear Information System (INIS)

1995-01-01

The following topical issues related to nuclear safety are discussed: steam generators; maintenance strategies; control rod drive nozzle cracks; core shrouds cracks; sump strainer blockage; fire protection; computer software important for safety; safety during shutdown; operational safety experience; external hazards and other site related issues. 5 figs, 5 tabs

Aviation Safety Issues Database

Science.gov (United States)

Morello, Samuel A.; Ricks, Wendell R.

2009-01-01

The aviation safety issues database was instrumental in the refinement and substantiation of the National Aviation Safety Strategic Plan (NASSP). The issues database is a comprehensive set of issues from an extremely broad base of aviation functions, personnel, and vehicle categories, both nationally and internationally. Several aviation safety stakeholders such as the Commercial Aviation Safety Team (CAST) have already used the database. This broader interest was the genesis to making the database publically accessible and writing this report.

Safety design criteria for the next generation Sodium-cooled fast reactors based on lessons learned from the Fukushima NPS accident

International Nuclear Information System (INIS)

Sakai, Takaaki

2012-01-01

In this presentation, architecture of the safety design criteria as requirements for SFR system and the activities on safety research works to establish safety evaluation methods for the next generation SFRs are summarized with the basis on lessons learned from the Fukushima NPS accident. Nuclear safety is a grovel issue which should be achieved by the international cooperation. In respect of the development for the next generation reactor, it is necessary to build the harmonized safety criteria and evaluation methods to establish the next level of safety

Prioritization of generic safety issues

International Nuclear Information System (INIS)

Emrit, R.; Minners, W.; VanderMolen, H.

1983-12-01

This report presents the priority rankings for generic safety issues related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The report focuses on the prioritization of generic safety issues. Issues primarily concerned with the licensing process or environmental protection and not directly related to safety have been excluded from prioritization. The prioritized issues include: TMI Action Plan items under development; previously proposed issues covered by Task Action Plans, except issues designated at Unresolved Safety Issues (USIs) which had already been assigned high priority; and newly-proposed issues. Future supplements to this report will include the prioritization of additional issues. The safety priority rankings are HIGH, MEDIUM, LOW, and DROP and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolutions of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative

Modeling issues associated with production reactor safety assessment

International Nuclear Information System (INIS)

Stack, D.W.; Thomas, W.R.

1990-01-01

This paper describes several Probabilistic Safety Assessment (PSA) modeling issues that are related to the unique design and operation of the production reactors. The identification of initiating events and determination of a set of success criteria for the production reactors is of concern because of their unique design. The modeling of accident recovery must take into account the unique operation of these reactors. Finally, a more thorough search and evaluation of common-cause events is required to account for combinations of unique design features and operation that might otherwise not be included in the PSA. It is expected that most of these modeling issues also would be encountered when modeling some of the other more unique reactor and nonreactor facilities that are part of the DOE nuclear materials production complex. 9 refs., 2 figs

Planning and Preparing for Emergency Response to Transport Accidents Involving Radioactive Material. Safety Guide

International Nuclear Information System (INIS)

2009-01-01

This Safety Guide provides guidance on various aspects of emergency planning and preparedness for dealing effectively and safely with transport accidents involving radioactive material, including the assignment of responsibilities. It reflects the requirements specified in Safety Standards Series No. TS-R-1, Regulations for the Safe Transport of Radioactive Material, and those of Safety Series No. 115, International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. Contents: 1. Introduction; 2. Framework for planning and preparing for response to accidents in the transport of radioactive material; 3. Responsibilities for planning and preparing for response to accidents in the transport of radioactive material; 4. Planning for response to accidents in the transport of radioactive material; 5. Preparing for response to accidents in the transport of radioactive material; Appendix I: Features of the transport regulations influencing emergency response to transport accidents; Appendix II: Preliminary emergency response reference matrix; Appendix III: Guide to suitable instrumentation; Appendix IV: Overview of emergency management for a transport accident involving radioactive material; Appendix V: Examples of response to transport accidents; Appendix VI: Example equipment kit for a radiation protection team; Annex I: Example of guidance on emergency response to carriers; Annex II: Emergency response guide.

Overview of IRSN R and D on NPP safety, with focus on severe accident

International Nuclear Information System (INIS)

Van Dorsselaere, Jean-Pierre

2015-01-01

IRSN contributes to the continuous improvement of safety level of Gen.II and III reactors, with the aim to approach for Gen.II the target safety level of Gen.III. This needs to build the necessary knowledge to appreciate margins for safety important systems, structures and components in the frame of plant operation life extension beyond 40 years. Research is a major IRSN mission that is tightly linked to expertise needs: it involves 40% of overall budget and, out of radiation protection and safety of waste disposal, around 280 scientists. IRSN has acquired a huge experience in the last 30 years on severe accidents, both on experimental and theoretical aspects, in particular through management of large international research programmes like the Phébus. FP integral experiments in the last 20 years and the coordination of the SARNET network of excellence that continues now in the frame of the NUGENIA European association. Besides, IRSN is developing, in collaboration with GRS (Germany), the integral system code ASTEC that is considered now as the European reference code due to the continuous capitalization of all the international knowledge. The presentation summarizes the ongoing IRSN research on the different phenomena involved in severe accidents, with more focus in the last years on mitigation devices or measures, i.e. for in-vessel and ex-vessel corium coolability, hydrogen explosion risk and source term. IRSN leads several international projects in Euratom frame (such as CESAM on ASTEC, PASSAM on source term mitigation, and IVMR on in-vessel corium retention) or OECD/NEA/CSNI (such as STEM). Moreover, several national projects on the above issues are ongoing with the French actors in this domain. Collaboration between IRSN and India is very active and efficient on ASTEC code with BARC and AERB, in particular through PHWR model development and assessment, and could be extended in the future to other issues either on severe accidents or on other Topics. (author)

Golfech plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Golfech plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Tricastin plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Tricastin plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Bugey plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Bugey plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Fessenheim plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Fessenheim plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Chinon plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Chinon B plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Blayais plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Blayais plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Civaux plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Civaux plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Cattenom plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Cattenom plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Gravelines plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Gravelines plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Current issues in developing safety culture while establishing wind energy power plants in India

Energy Technology Data Exchange (ETDEWEB)

Gowda, M.C.M.; Repaka, B.; Gowda, P. [MSRIT Research Centre, Bangalore (India); Chandrashekar, R. [SaIT, Bangalore (India)

2012-07-01

Safety is important to every one working in the various organizations. They want to be safe when coming to work, at the time of work and going back to home. The ultimate aim of every worker is to work for the needs/money and or satisfaction where these would get prioritized according to the individuals. People don't want accidents to happen. People don't want to get themselves injured nor their colleagues. People would like and love to work in a company which cares for them and keeps them safe. Having said this then what makes them meet with or see an accident in the wind farm? Yes it is the unsafe act and unsafe condition which causes an accident in the wind farm. The present study put forward the factors /issues that influence people behaviors as part of weakening the safety culture to perform an unsafe act or to ignore and work in an unsafe condition. (Author)

CANDU safety under severe accidents

International Nuclear Information System (INIS)

Snell, V.G.; Howieson, J.Q.; Alikhan, S.; Frescura, G.M.; King, F.; Rogers, J.T.; Tamm, H.

1996-01-01

The characteristics of the CANDU reactor relevant to severe accidents are set first by the inherent properties of the design, and second by the Canadian safety/licensing approach. The pressure-tube concept allows the separate, low-pressure, heavy-water moderator to act as a backup heat sink even if there is no water in the fuel channels. Should this also fail, the calandria shell itself can contain the debris, with heat being transferred to the water-filled shield tank around the core. Should the severe core damage sequence progress further, the shield tank and the concrete reactor vault significantly delay the challenge to containment. Furthermore, should core melt lead to containment overpressure, the containment behaviour is such that leaks through the concrete containment wall reduce the possibility of catastrophic structural failure. The Canadian licensing philosophy requires that each accident, together with failure of each safety system in turn, be assessed (and specified dose limits met) as part of the design and licensing basis. In response, designers have provided CANDUs with two independent dedicated shutdown systems, and the likelihood of Anticipated Transients Without Scram is negligible. Probabilistic safety assessment studies have been performed on operating CANDU plants, and on the 4 x 880 MW(e) Darlington station now under construction; furthermore a scoping risk assessment has been done for a CANDU 600 plant. They indicate that the summed severe core damage frequency is of the order of 5 x 10 -6 /year. 95 refs, 3 tabs

CANDU safety under severe accidents

Energy Technology Data Exchange (ETDEWEB)

Snell, V G; Howieson, J Q [Atomic Energy of Canada Ltd. (Canada); Alikhan, S [New Brunswick Electric Power Commission (Canada); Frescura, G M; King, F [Ontario Hydro (Canada); Rogers, J T [Carleton Univ., Ottawa, ON (Canada); Tamm, H [Atomic Energy of Canada Ltd. (Canada). Whiteshell Research Lab.

1996-12-01

The characteristics of the CANDU reactor relevant to severe accidents are set first by the inherent properties of the design, and second by the Canadian safety/licensing approach. The pressure-tube concept allows the separate, low-pressure, heavy-water moderator to act as a backup heat sink even if there is no water in the fuel channels. Should this also fail, the calandria shell itself can contain the debris, with heat being transferred to the water-filled shield tank around the core. Should the severe core damage sequence progress further, the shield tank and the concrete reactor vault significantly delay the challenge to containment. Furthermore, should core melt lead to containment overpressure, the containment behaviour is such that leaks through the concrete containment wall reduce the possibility of catastrophic structural failure. The Canadian licensing philosophy requires that each accident, together with failure of each safety system in turn, be assessed (and specified dose limits met) as part of the design and licensing basis. In response, designers have provided CANDUs with two independent dedicated shutdown systems, and the likelihood of Anticipated Transients Without Scram is negligible. Probabilistic safety assessment studies have been performed on operating CANDU plants, and on the 4 x 880 MW(e) Darlington station now under construction; furthermore a scoping risk assessment has been done for a CANDU 600 plant. They indicate that the summed severe core damage frequency is of the order of 5 x 10{sup -6}/year. 95 refs, 3 tabs.

Effect of Occupational Health and Safety Management System on Work-Related Accident Rate and Differences of Occupational Health and Safety Management System Awareness between Managers in South Korea's Construction Industry.

Science.gov (United States)

Yoon, Seok J; Lin, Hsing K; Chen, Gang; Yi, Shinjea; Choi, Jeawook; Rui, Zhenhua

2013-12-01

The study was conducted to investigate the current status of the occupational health and safety management system (OHSMS) in the construction industry and the effect of OHSMS on accident rates. Differences of awareness levels on safety issues among site general managers and occupational health and safety (OHS) managers are identified through surveys. The accident rates for the OHSMS-certified construction companies from 2006 to 2011, when the construction OHSMS became widely available, were analyzed to understand the effect of OHSMS on the work-related injury rates in the construction industry. The Korea Occupational Safety and Health Agency 18001 is the certification to these companies performing OHSMS in South Korea. The questionnaire was created to analyze the differences of OHSMS awareness between site general managers and OHS managers of construction companies. The implementation of OHSMS among the top 100 construction companies in South Korea shows that the accident rate decreased by 67% and the fatal accident rate decreased by 10.3% during the period from 2006 to 2011. The survey in this study shows different OHSMS awareness levels between site general managers and OHS managers. The differences were motivation for developing OHSMS, external support needed for implementing OHSMS, problems and effectiveness of implementing OHSMS. Both work-related accident and fatal accident rates were found to be significantly reduced by implementing OHSMS in this study. The differences of OHSMS awareness between site general managers and OHS managers were identified through a survey. The effect of these differences on safety and other benefits warrants further research with proper data collection.

The role of post accident chemistry data in nuclear safety

International Nuclear Information System (INIS)

Bradshaw, R.W.; Caruthers, G.F.

1982-01-01

The NRC instituted the NUREG-0737 requirements as implementation of the Post-TMI Action Plan in October, 1980. Among these requirements was the capability to obtain chemistry samples of the reactor coolant and containment building atmosphere under post accident conditions. The quantitative criteria were, in general, beyond the capabilities of existing plant systems. As a consequence the nuclear industry expended substantial efforts to design and install the post-accident sampling systems necessary to comply with these criteria. With such efforts essentially complete, the task remains to establish the role that data provided by these systems would play in mitigating the consequences of a nuclear plant accident. This role definition must include a characterization of the timing and priority for the post accident chemistry data. This paper defines that role using the Safety Level and Safety Function concepts as a matrix

Some outstanding issues in severe accidents containment performance

International Nuclear Information System (INIS)

Sehgal, B.R.

2004-01-01

This paper describes the current status of the outstanding issues in severe accident performance of Light Water Reactor containments that have been raised in the last several years. The results of the research that has been performed on the topics concerning these issues will be described. Some of these issues have been resolved, some are close to resolution, while others need further evaluation and research results. (author)

Use of probabilistic safety analyses in severe accident management

International Nuclear Information System (INIS)

Neogy, P.; Lehner, J.

1991-01-01

An important consideration in the development and assessment of severe accident management strategies is that while the strategies are often built on the knowledge base of Probabilistic Safety Analyses (PSA), they must be interpretable and meaningful in terms of the control room indicators. In the following, the relationships between PSA and severe accident management are explored using ex-vessel accident management at a PWR ice-condenser plant as an example. 2 refs., 1 fig., 3 tabs

A Tool for Safety Officers Investigating " simple" Accidents

DEFF Research Database (Denmark)

Jørgensen, Kirsten

2010-01-01

Most workplace accidents that happen in enterprises are simple and seldom result in serious injuries. Very often these kinds of workplace accidents are not investigated, and if they are, then the investigation is very brief, with comments such as that it was the victim’s own fault or just...... accidents normally caused by apparent banalities occur much more frequently and with a higher rate of fatalities, disablements and other serious injuries than the ostensibly most dangerous kinds of accidents. In 1999 a practical tool for use by safety officers was developed; this tool is based...... on the investigation methods applied in major accidents, but comprises a simpler and more user-friendly presentation. The tool involves three steps: Mapping the facts, analysing the events, and developing preventive solutions. Practical application of the tool has shown that it affords managers and workers...

Severe accident approach - final report. Evaluation of design measures for severe accident prevention and consequence mitigation

International Nuclear Information System (INIS)

Tentner, A.M.; Parma, E.; Wei, T.; Wigeland, R.

2010-01-01

An important goal of the US DOE reactor development program is to conceptualize advanced safety design features for a demonstration Sodium Fast Reactor (SFR). The treatment of severe accidents is one of the key safety issues in the design approach for advanced SFR systems. It is necessary to develop an in-depth understanding of the risk of severe accidents for the SFR so that appropriate risk management measures can be implemented early in the design process. This report presents the results of a review of the SFR features and phenomena that directly influence the sequence of events during a postulated severe accident. The report identifies the safety features used or proposed for various SFR designs in the US and worldwide for the prevention and/or mitigation of Core Disruptive Accidents (CDA). The report provides an overview of the current SFR safety approaches and the role of severe accidents. Mutual understanding of these design features and safety approaches is necessary for future collaborations between the US and its international partners as part of the GEN IV program. The report also reviews the basis for an integrated safety approach to severe accidents for the SFR that reflects the safety design knowledge gained in the US during the Advanced Liquid Metal Reactor (ALMR) and Integral Fast Reactor (IFR) programs. This approach relies on inherent reactor and plant safety performance characteristics to provide additional safety margins. The goal of this approach is to prevent development of severe accident conditions, even in the event of initiators with safety system failures previously recognized to lead directly to reactor damage.

Severe accident approach - final report. Evaluation of design measures for severe accident prevention and consequence mitigation.

Energy Technology Data Exchange (ETDEWEB)

Tentner, A. M.; Parma, E.; Wei, T.; Wigeland, R.; Nuclear Engineering Division; SNL; INL

2010-03-01

An important goal of the US DOE reactor development program is to conceptualize advanced safety design features for a demonstration Sodium Fast Reactor (SFR). The treatment of severe accidents is one of the key safety issues in the design approach for advanced SFR systems. It is necessary to develop an in-depth understanding of the risk of severe accidents for the SFR so that appropriate risk management measures can be implemented early in the design process. This report presents the results of a review of the SFR features and phenomena that directly influence the sequence of events during a postulated severe accident. The report identifies the safety features used or proposed for various SFR designs in the US and worldwide for the prevention and/or mitigation of Core Disruptive Accidents (CDA). The report provides an overview of the current SFR safety approaches and the role of severe accidents. Mutual understanding of these design features and safety approaches is necessary for future collaborations between the US and its international partners as part of the GEN IV program. The report also reviews the basis for an integrated safety approach to severe accidents for the SFR that reflects the safety design knowledge gained in the US during the Advanced Liquid Metal Reactor (ALMR) and Integral Fast Reactor (IFR) programs. This approach relies on inherent reactor and plant safety performance characteristics to provide additional safety margins. The goal of this approach is to prevent development of severe accident conditions, even in the event of initiators with safety system failures previously recognized to lead directly to reactor damage.

78 FR 14877 - Pipeline Safety: Incident and Accident Reports

Science.gov (United States)

2013-03-07

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket ID PHMSA-2013-0028] Pipeline Safety: Incident and Accident Reports AGENCY: Pipeline and Hazardous Materials... PHMSA F 7100.2--Incident Report--Natural and Other Gas Transmission and Gathering Pipeline Systems and...

Safety evaluation of accident-tolerant FCM fueled core with SiC-coated zircalloy cladding for design-basis-accidents and beyond DBAs

Energy Technology Data Exchange (ETDEWEB)

Chun, Ji-Han, E-mail: chunjh@kaeri.re.kr; Lim, Sung-Won; Chung, Bub-Dong; Lee, Won-Jae

2015-08-15

Highlights: • Thermal conductivity model of the FCM fuel was developed and adopted in the MARS. • Scoping analysis for candidate FCM FAs was performed to select feasible FA. • Preliminary safety criteria for FCM fuel and SiC/Zr cladding were set up. • Enhanced safety margin and accident tolerance for FCM-SiC/Zr core were demonstrated. - Abstract: The FCM fueled cores proposed as an accident tolerant concept is assessed against the design-basis-accident (DBA) and the beyond-DBA (BDBA) scenarios using MARS code. A thermal conductivity model of FCM fuel is incorporated in the MARS code to take into account the effects of irradiation and temperature that was recently measured by ORNL. Preliminary analyses regarding the initial stored energy and accident tolerant performance were carried out for the scoping of various cladding material candidates. A 16 × 16 FA with SiC-coated Zircalloy cladding was selected as the feasible conceptual design through a preliminary scoping analysis. For a selected design, safety analyses for DBA and BDBA scenarios were performed to demonstrate the accident tolerance of the FCM fueled core. A loss of flow accident (LOFA) scenario was selected for a departure-from-nucleate-boiling (DNB) evaluation, and large-break loss of coolant accident (LBLOCA) scenario for peak cladding temperature (PCT) margin evaluation. A control element assembly (CEA) ejection accident scenario was selected for peak fuel enthalpy and temperature. Moreover, a station blackout (SBO) and LBLOCA without a safety injection (SI) scenario were selected as a BDBA. It was demonstrated that the DBA safety margin of the FCM core is satisfied and the time for operator actions for BDBA s is evaluated.

Having a New Pair of Glassess : Applying Systemic Accident Models on Road Safety

OpenAIRE

Huang, Yu-Hsing

2007-01-01

The main purpose of the thesis is to discuss the accident models which underlie accident prevention in general and road safety in particular, and the consequences of relying on a particular model have for actual preventive work. The discussion centres on two main topics. The first topic is whether the underlying accident model, or paradigm, of traditional road safety should be exchanged for a more complex accident model, and if so, which model(s) are appropriate. From a discussion of current ...

Safety during sea transport of radioactive materials. Probabilistic safety analysis of package fro sea surface fire accident

International Nuclear Information System (INIS)

Matsuoka, Takeshi; Obara, Isonori; Akutsu, Yukio; Aritomi, Masanori

2000-01-01

The ships carrying irradiated nuclear fuel, plutonium and high level radioactive wastes(INF materials) are designed to keep integrity of packaging based on the various safety and fireproof measures, even if the ship encounters a maritime fire accident. However, granted that the frequency is very low, realistic severe accidents should be evaluated. In this paper, probabilistic safety assessment method is applied to evaluate safety margin for severe sea fire accidents using event tree analysis. Based on our separate studies, the severest scenario was estimated as follows; an INF transport ship collides with oil tanker and induces a sea surface fire. Probability data such as ship's collision, oil leakage, ignition, escape from fire region, operations of cask cooling system and water flooding systems were also introduced from above mentioned studies. The results indicate that the probability of which packages cannot keep their integrity during the sea surface fire accident is very low and sea transport of INF materials is carried out very safely. (author)

Nuclear Reactor RA Safety Report, Vol. 16, Maximum hypothetical accident

International Nuclear Information System (INIS)

1986-11-01

Fault tree analysis of the maximum hypothetical accident covers the basic elements: accident initiation, phase development phases - scheme of possible accident flow. Cause of the accident initiation is the break of primary cooling pipe, heavy water system. Loss of primary coolant causes loss of pressure in the primary circuit at the coolant input in the reactor vessel. This initiates safety protection system which should automatically shutdown the reactor. Separate chapters are devoted to: after-heat removal, coolant and moderator loss; accident effects on the reactor core, effects in the reactor building, and release of radioactive wastes [sr

Regulatory analyses for severe accident issues: an example

International Nuclear Information System (INIS)

Burke, R.P.; Strip, D.R.; Aldrich, D.C.

1984-09-01

This report presents the results of an effort to develop a regulatory analysis methodology and presentation format to provide information for regulatory decision-making related to severe accident issues. Insights and conclusions gained from an example analysis are presented. The example analysis draws upon information generated in several previous and current NRC research programs (the Severe Accident Risk Reduction Program (SARRP), Accident Sequence Evaluation Program (ASEP), Value-Impact Handbook, Economic Risk Analyses, and studies of Vented Containment Systems and Alternative Decay Heat Removal Systems) to perform preliminary value-impact analyses on the installation of either a vented containment system or an alternative decay heat removal system at the Peach Bottom No. 2 plant. The results presented in this report are first-cut estimates, and are presented only for illustrative purposes in the context of this document. This study should serve to focus discussion on issues relating to the type of information, the appropriate level of detail, and the presentation format which would make a regulatory analysis most useful in the decisionmaking process

Safety issues of dry fuel storage at RSWF

International Nuclear Information System (INIS)

Clarksean, R.L.; Zahn, T.P.

1995-01-01

Safety issues associated with the dry storage of EBR-II spent fuel are presented and discussed. The containers for the fuel have been designed to prevent a leak of fission gases to the environment. The storage system has four barriers for the fission gases. These barriers are the fuel cladding, an inner container, an outer container, and the liner at the RSWF. Analysis has shown that the probability of a leak to the environment is much less than 10 -6 per year, indicating that such an event is not considered credible. A drop accident, excessive thermal loads, criticality, and possible failure modes of the containers are also addressed

Review of light water reactor safety through the Three Mile Island accident

International Nuclear Information System (INIS)

Phung, D.L.

1984-05-01

This review of light water reactor safety through the Three Mile Island accident has the purpose of establishing the baseline over which safety achievement post-TMI is assessed, and the need for new reactor designs and business direction is judged. Five major areas of reactor safety pre-TMI are examined: (1) safety philosophy and institutions, (2) reactor design criteria, (3) operational problems, (4) the Rasmussen reactor safety study, and (5) the TMI accident and repercussions. Although nuclear power has made spectacular achievements over the period pre-TMI and although TMI is technically a minor accident, this review concludes that there were basic flaws in the technology and in the manner safety philosophy was conceived and carried out. These flaws included (1) a reactor design that has high core power density, low heat capacity, and low system tolerance to upsets, (2) reactor deployment that had been expedited without extensive operational experience, (3) rules and regulations that had to play catch-up with commercial reactor development, (4) an industry that was fragmented, short-sighted, and tended to rely on the Nuclear Regulatory Commission for safety guidance, (5) information that was not effectively shared, and (6) attention that was inadequate to the human aspects of reactor operation and to public reaction to the specter of a reactor accident, major or minor

Saint-Alban plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Saint-Alban plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Control of Industrial Safety Based on Dynamic Characteristics of a Safety Budget-Industrial Accident Rate Model in Republic of Korea.

Science.gov (United States)

Choi, Gi Heung; Loh, Byoung Gook

2017-06-01

Despite the recent efforts to prevent industrial accidents in the Republic of Korea, the industrial accident rate has not improved much. Industrial safety policies and safety management are also known to be inefficient. This study focused on dynamic characteristics of industrial safety systems and their effects on safety performance in the Republic of Korea. Such dynamic characteristics are particularly important for restructuring of the industrial safety system. The effects of damping and elastic characteristics of the industrial safety system model on safety performance were examined and feedback control performance was explained in view of cost and benefit. The implications on safety policies of restructuring the industrial safety system were also explored. A strong correlation between the safety budget and the industrial accident rate enabled modeling of an industrial safety system with these variables as the input and the output, respectively. A more effective and efficient industrial safety system could be realized by having weaker elastic characteristics and stronger damping characteristics in it. A substantial decrease in total social cost is expected as the industrial safety system is restructured accordingly. A simple feedback control with proportional-integral action is effective in prevention of industrial accidents. Securing a lower level of elastic industrial accident-driving energy appears to have dominant effects on the control performance compared with the damping effort to dissipate such energy. More attention needs to be directed towards physical and social feedbacks that have prolonged cumulative effects. Suggestions for further improvement of the safety system including physical and social feedbacks are also made.

LMFBR safety. 5. Review of current issues and bibliography of literature (1975--1976)

International Nuclear Information System (INIS)

Buchanan, J.R.; Keilholtz, G.W.

1977-01-01

The current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA), are discussed. Bibliographic information on worldwide LMFBRs relative to the development and safety of the breeder reactor is presented for the period 1975 through 1976. The bibliography consists of approximately 1618 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Keyword, author, and permuted-title indexes are included for completeness

LMFBR safety. 5. Review of current issues and bibliography of literature (1975--1976)

Energy Technology Data Exchange (ETDEWEB)

Buchanan, J.R.; Keilholtz, G.W.

1977-06-08

The current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA), are discussed. Bibliographic information on worldwide LMFBRs relative to the development and safety of the breeder reactor is presented for the period 1975 through 1976. The bibliography consists of approximately 1618 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Keyword, author, and permuted-title indexes are included for completeness.

Emergency response and nuclear risk governance. Nuclear safety at nuclear power plant accidents

International Nuclear Information System (INIS)

Kuhlen, Johannes

2014-01-01

The present study entitled ''Emergency Response and Nuclear Risk Governance: nuclear safety at nuclear power plant accidents'' deals with issues of the protection of the population and the environment against hazardous radiation (the hazards of nuclear energy) and the harmful effects of radioactivity during nuclear power plant accidents. The aim of this study is to contribute to both the identification and remediation of shortcomings and deficits in the management of severe nuclear accidents like those that occurred at Chernobyl in 1986 and at Fukushima in 2011 as well as to the improvement and harmonization of plans and measures taken on an international level in nuclear emergency management. This thesis is divided into a theoretical part and an empirical part. The theoretical part focuses on embedding the subject in a specifically global governance concept, which includes, as far as Nuclear Risk Governance is concerned, the global governance of nuclear risks. Due to their characteristic features the following governance concepts can be assigned to these risks: Nuclear Safety Governance is related to safety, Nuclear Security Governance to security and NonProliferation Governance to safeguards. The subject of investigation of the present study is as a special case of the Nuclear Safety Governance, the Nuclear Emergency governance, which refers to off-site emergency response. The global impact of nuclear accidents and the concepts of security, safety culture and residual risk are contemplated in this context. The findings (accident sequences, their consequences and implications) from the analyses of two reactor accidents prior to Fukushima (Three Mile Iceland in 1979, Chernobyl in 1986) are examined from a historical analytical perspective and the state of the Nuclear Emergency governance and international cooperation aimed at improving nuclear safety after Chernobyl is portrayed by discussing, among other topics, examples of &apos

Impact of the Three Mile Island accident on reactor safety and licensing in Canada

International Nuclear Information System (INIS)

Harvie, J.D.

1980-06-01

This paper discusses the implications of the accident at Three Mile Island on reactor safety and licensing in Canada. Reactor safety principles which can be learned from, or are reaffirmed by, the accident are reviewed. It is concluded that reactor safety demands a firm commitment to safety by all those involved in the nuclear industry. (auth)

Phenix plant - Complementary safety assessment of the Phenix plant (INB 71) in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Phenix reactor to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. The Phenix reactor stands on the Marcoule site of CEA and was stopped definitely in 2009 for electricity production. Robustness is the ability for the facility to withstand events beyond the level for which the facility was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence (cliff edge effect). Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like crisis organization and work organization via subcontracting are also taken into consideration. This report is divided into 9 main chapters: 1) main features of the Phenix facility, 2) identification of cliff edge risks as well as structures and equipment essential to safety, 3) earthquake risk, 4) flood risk, 5) risks due to other extreme natural disasters, 6) the loss of electrical power supplies and of cooling systems, 7) management of severe accidents, 8) subcontracting policy, 9) synthesis. This study shows that it is necessary to take some measures to reinforce the robustness of the plant concerning flood risks. (A.C.)

Eminent radiological safety issues confronting the State of Hawaii

International Nuclear Information System (INIS)

Hashimoto, H.H.

1984-01-01

The State of Hawaii currently has over one hundred radioactive material use licenses. Nuclear Regulatory Commission licenses are primarily held by hospitals, industrial radiographers, and academic institutions. Complementing this, the State Department of Health regulates x-ray machines, radium, and has an emergency response role for accidents involving radioactive materials. The existing radiation protection program was created by piecemeal legislation. As a result, regulatory surveillance and actual control vary widely among the agencies. The State Legislature, in 1980, decided that action must be taken to set a clear state policy towards the use and disposal of nuclear materials. It was therefore recommended that the State of Hawaii Radiation Safety Advisory Committee be convened to assist the state in the evaluation of the issues. This report contains issue papers on radiation related topics addressed by the Radiation Safety Advisory Committe. Topics discussed include transportation, environmental monitoring, emergency response, and waste disposal. A survey of various radioactive sources identified medical applications as a category requiring stricter control. Selected chapters of the Hawaii Revised Statutes are also examined

An analysis on human factor issues in criticality accident at a uranium processing plant

International Nuclear Information System (INIS)

Sasou, Kunihide; Goda, Hidenori; Hirotsu, Yuko

2000-01-01

This report analyses latent factors of a human behavior directly contributing to the criticality accident. It is pouring some 16 kg-U with an enrichment of 18.8% into the precipitation tank. It is the fact that the direct cause of this accident is the workers' unsafe act. However, the authors find lots of latent factors relating to the production-biased company's policy, the poor climate for safety in the work place, the inadequate safety management and the unsuitable equipment. This accident was caused by many organizational factors. This paper also discusses lessons learned from this accident. (author)

Passive Decay Heat Removal Strategy of Integrated Passive Safety System (IPSS) for SBO-combined Accidents

Energy Technology Data Exchange (ETDEWEB)

Kim, Sang Ho; Chang, Soon Heung; Jeong, Yong Hoon [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

2014-10-15

The weak points of nuclear safety would be in outmoded nuclear power plants like the Fukushima reactors. One of the systems for the safety enhancement is integrated passive safety system (IPSS) proposed after the Fukushima accidents. It has the five functions for the prevention and mitigation of a severe accident. Passive decay heat removal (PDHR) strategy using IPSS is proposed for coping with SBO-combined accidents in this paper. The two systems for removing decay heat before core-melt were applied in the strategy. The accidents were simulated by MARS code. The reference reactor was OPR1000, specifically Ulchin-3 and 4. The accidents included loss-of-coolant accidents (LOCA) because the coolant losses could be occurred in the SBO condition. The examples were the stuck open of PSV, the abnormal open of SDV and the leakage of RCP seal water. Also, as LOCAs with the failure of active safety injection systems were considered, various LOCAs were simulated in SBO. Based on the thermal hydraulic analysis, the probabilistic safety analysis was carried out for the PDHR strategy to estimate the safety enhancement in terms of the variation of core damage frequency. AIMS-PSA developed by KAERI was used for calculating CDF of the plant. The IPSS was applied in the PDHR strategy which was developed in order to cope with the SBO-combined accidents. The estimation for initiating SGGI or PSIS was based on the pressure in RCS. The simulations for accidents showed that the decay heat could be removed for the safety duration time in SBO. The increase of safety duration time from the strategy provides the increase of time for the restoration of AC power.

Accident consequence calculations for project W-058 safety analysis

International Nuclear Information System (INIS)

Van Keuren, J.C.

1997-01-01

This document describes the calculations performed to determine the accident consequences for the W-058 safety analysis. Project W-058 is the replacement cross site transfer system (RCSTS), which is designed to transort liquid waste between the 200 W and 200 E areas. Calculations for RCSTS safety analyses used the same methods as the calculations for the Tank Waste Remediation System (TWRS) Basis for Interim Operation (BIO) and its supporting calculation notes. Revised analyses were performed for the spray and pool leak accidents since the RCSTS flows and pressures differ from those assumed in the TWRS BIO. Revision 1 of the document incorporates review comments

A brief overview of Ignalina NPP safety issues

International Nuclear Information System (INIS)

Almenas, K.; Ushpuras, E.

1998-01-01

A description of the safety of Ignalina NPP in a very popular form is presented. Answers to the most frequently recurring questions concerning the Ignalina NPP are provided based on recently completed international studies. Questions are like these: can a similar accident to the one that occurred in Chernobyl take place at Ignalina NPP, does the Ignalina NPP have a containment, what are the probabilities and potential consequences of accidents, etc. The brochure contains a short description of Ignalina NPP safety improvement programs

Evaluation of severe accident safety system value based on averting financial risks

International Nuclear Information System (INIS)

Hatch, S.W.; Benjamin, A.S.; Bennett, P.R.

1983-01-01

The Severe Accident Risk Reduction Program is being performed to benchmark the risks from nuclear power plants and to assess the benefits and impacts of a set of severe accident safety features. This paper describes the program in general and presents some preliminary results. These results include estimates of the financial risks associated with the operation of six reference plants and the value of severe accident prevention and mitigation safety systems in averting these risks. The results represent initial calculations and will be iterated before being used to support NRC decisions

OVERVIEW OF MODULAR HTGR SAFETY CHARACTERIZATION AND POSTULATED ACCIDENT BEHAVIOR LICENSING STRATEGY

Energy Technology Data Exchange (ETDEWEB)

Ball, Sydney J [ORNL

2014-06-01

This report provides an update on modular high-temperature gas-cooled reactor (HTGR) accident analyses and risk assessments. One objective of this report is to improve the characterization of the safety case to better meet current regulatory practice, which is commonly geared to address features of today s light water reactors (LWRs). The approach makes use of surrogates for accident prevention and mitigation to make comparisons with LWRs. The safety related design features of modular HTGRs are described, along with the means for rigorously characterizing accident selection and progression methodologies. Approaches commonly used in the United States and elsewhere are described, along with detailed descriptions and comments on design basis (and beyond) postulated accident sequences.

ACCIDENT ANALYSES & CONTROL OPTIONS IN SUPPORT OF THE SLUDGE WATER SYSTEM SAFETY ANALYSIS

Energy Technology Data Exchange (ETDEWEB)

WILLIAMS, J.C.

2003-11-15

This report documents the accident analyses and nuclear safety control options for use in Revision 7 of HNF-SD-WM-SAR-062, ''K Basins Safety Analysis Report'' and Revision 4 of HNF-SD-SNF-TSR-001, ''Technical Safety Requirements - 100 KE and 100 KW Fuel Storage Basins''. These documents will define the authorization basis for Sludge Water System (SWS) operations. This report follows the guidance of DOE-STD-3009-94, ''Preparation Guide for US. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports'', for calculating onsite and offsite consequences. The accident analysis summary is shown in Table ES-1 below. While this document describes and discusses potential control options to either mitigate or prevent the accidents discussed herein, it should be made clear that the final control selection for any accident is determined and presented in HNF-SD-WM-SAR-062.

Emergency Response to Radioactive Material Transport Accidents

International Nuclear Information System (INIS)

EL-shinawy, R.M.K.

2009-01-01

Although transport regulations issued by IAEA is providing a high degree of safety during transport opertions,transport accidents involving packages containing radioactive material have occurred and will occur at any time. Whenever a transport accident involving radioactive material accurs, and many will pose no radiation safety problems, emergency respnose actioms are meeded to ensure that radiation safety is maintained. In case of transport accident that result in a significant relesae of radioactive material , loss of shielding or loss of criticality control , that consequences should be controlled or mitigated by proper emergency response actions safety guide, Emergency Response Plamming and Prepardness for transport accidents involving radioactive material, was published by IAEA. This guide reflected all requirememts of IAEA, regulations for safe transport of radioactive material this guide provide guidance to the publicauthorites and other interested organziation who are responsible for establishing such emergency arrangements

Safety issues on advanced fuel

Energy Technology Data Exchange (ETDEWEB)

Gross, H.; Krebs, W.D. [Siemens AG, Bereich Energieerzeugug (KWU), Erlangen (Germany). Geschaeftsgebiet Nukleare Energieerzeugung

1998-05-01

In the recent years a general discussion has started whether unsolved safety issues are related to advanced fuel. Advanced fuel is in this context a summary of features like high burnup, improved clad materials, low leakage loading pattern with high peaking factors etc. The design basis accidents RIA and Loca are of special interest for this discussion. From the Siemens point of view RIA is not a safety issue. There are sufficient margins between the enthalpy rise calculated by modern 3D methods and the fuel failures which occurred in RIA simulation tests when the effect of pulse width is taken into account. The evaluation of possible uncertainties for the established Loca criteria (17% equivalent corrosion, 1200 C clad temperature) for high burnup makes sense. But fuel with high burnup has significantly lower peaking factors than fuel with lower burnup. This gives sufficient margin counterbalancing possible uncertainties. In contrast to the above incomplete control rod insertion at higher burnup is potentially a real safety issue. Although Siemens fuel was not affected by the reported incidents they addressed the problem and checked that they have sufficient design margin for their fuel. (orig.) [Deutsch] In den letzten Jahren hat eine allgemeine Diskussion begonnen, ob mit fortgeschrittenen Brennelementen (BE) ungeklaerte Sicherheitsprobleme verbunden sind. Dabei ist `Fortgeschrittene Brennelemente` ein Sammelbegriff fuer hohe Abbraende, verbesserte Huellrohrmaterialien, Low-leakage-Einsatzplanungen mit hohen Heissstellenfaktoren usw. Die Auslegungsstoerfaelle RIA und Loca sind in dieser Diskussion von besonderer Bedeutung. Aus der Sicht von Siemens ist der RIA kein Sicherheitsproblem. Zwischen den mit modernen 3D-Methoden berechneten Enthalpieerhoehungen und den in RIA-Experimenten aufgetretenen Brennstabdefekten bestehen ausreichende Abstaende, wenn der Einfluss der Pulsbreite beruecksichtigt wird. Die Untersuchung eventueller Unsicherheiten bei hohen

The accident at Chernobyl and its implications for the safety of CANDU reactors

International Nuclear Information System (INIS)

1987-05-01

In August 1986, a delegation of Canadians, including two members of the staff of the AECB (Atomic Energy Control Board), attended a post-accident review meeting in Vienna, at which Soviet representatives described the accident and its causes and consequences. On the basis of the information presented at that meeting, AECB staff conducted a study of the accident to ascertain its implications for the safety of CANDU nuclear reactors and for the regulatory process in Canada. The conclusion of this review is that the accident at Chernobyl has not revealed any important new information which would have an effect on the safety requirements for CANDU reactors as presently applied by the AECB. All important aspects of the accident and its causes have been considered by the AECB in the licensing process for currently licensed reactors. However a number of recommendations are made with respect to aspects of reactor safety which should be re-examined in order to reinforce this conclusion

Dampierre-en-Burly plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Dampierre-en-Burly plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Belleville-sur-Loire plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Belleville-sur-Loire plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

Nogent-sur-Seine plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Nogent-sur-Seine plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

A prioritization of generic safety issues

International Nuclear Information System (INIS)

Emrit, R.; Riggs, R.; Milstead, W.; Pittman, J.

1991-07-01

This report presents the priority rankings for generic safety issues and related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The report focuses on the prioritization of generic safety issues. Issues primarily concerned with the licensing process or environmental protection and not directly related to safety have been excluded from prioritization. The prioritized issues include: TMI Action Plan items under development; previously proposed issues covered by Task Action Plans, except issues designated as Un-resolved Safety Issues (USIs) which had already been assigned high priority; and newly-proposed issues. Future supplements to this report will include the prioritization of additional issues. The safety priority rankings are High, Medium, Low, and Drop and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolutions of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative. 1310 refs

Lessons Learned and Regulatory Countermeasures of Nuclear Safety Issues Last Year

Energy Technology Data Exchange (ETDEWEB)

Lee, Y. E. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2013-05-15

Competitiveness of nuclear as the electric resource in terms of the least cost and the carbon abatement has been debated. Some institutions insist that the radioactive wastes management cost, nuclear accident cost and cheap shale gas would make the nuclear energy less competitive, while others still address the ability of nuclear energy as economical and low-carbon electric resource. This situation reminds that ensuring nuclear safety is the most important prerequisite to use of nuclear energy. Therefore, this paper will compare the different views on future nuclear competitiveness discussed right after the Fukushima accident and summarize the lessons learned and regulatory countermeasures from nuclear safety issues last year. Korea has improved the effectiveness of safety regulation up to now and still has been making efforts on further enhancing nuclear safety. The outcomes of these efforts have resulted in a high level of safety in Korean NPPs and contributing largely to the global nuclear safety through sharing and exchanging the information and knowledge of our nuclear experiences. However, now we are faced with the new challenges such as decreasing the public. Additionally, public criticism of the regulatory activities demands more clear regulatory guides and transparent process. Recently, new president announced the 'Priority to Safety and Public Trust' as the precondition to utilize the nuclear energy. We will continue to make much more efforts for the improvement of the quality of regulatory activities and effectiveness of regulatory decision making process than we have done so far. Competence through effective capacity building would be a helpful pathway to build up the public trust and ensure the acceptable level of nuclear safety. We are set to prepare the action items to be taken in the near future for improving the technical competency and transparency as the essential components of the national safety and will make efforts to implement them

Mitigation of Hydrogen Hazards in Severe Accidents in Nuclear Power Plants

International Nuclear Information System (INIS)

2011-07-01

Consideration of severe accidents in nuclear power plants is an essential component of the defence in depth approach in nuclear safety. Severe accidents have very low probabilities of occurring, but may have significant consequences resulting from the degradation of nuclear fuel. The generation of hydrogen and the risk of hydrogen combustion, as well as other phenomena leading to overpressurization of the reactor containment in case of severe accidents, represent complex safety issues in relation to accident management. The combustion of hydrogen, produced primarily as a result of heated zirconium metal reacting with steam, can create short term overpressure or detonation forces that may exceed the strength of the containment structure. An understanding of these phenomena is crucial for planning and implementing effective accident management measures. Analysis of all the issues relating to hydrogen risk is an important step for any measure that is aimed at the prevention or mitigation of hydrogen combustion in reactor containments. The main objective of this publication is to contribute to the implementation of IAEA Safety Standards, in particular, two IAEA Safety Requirements: Safety of Nuclear Power Plants: Design and Safety of Nuclear Power Plants: Operation. These Requirements publications discuss computational analysis of severe accidents and accident management programmes in nuclear power plants. Specifically with regard to the risk posed by hydrogen in nuclear power reactors, computational analysis of severe accidents considers hydrogen sources, hydrogen distribution, hydrogen combustion and control and mitigation measures for hydrogen, while accident management programmes are aimed at mitigating hydrogen hazards in reactor containments.

Upgrading the safety toolkit: Initiatives of the accident analysis subgroup

International Nuclear Information System (INIS)

O'Kula, K.R.; Chung, D.Y.

1999-01-01

Since its inception, the Accident Analysis Subgroup (AAS) of the Energy Facility Contractors Group (EFCOG) has been a leading organization promoting development and application of appropriate methodologies for safety analysis of US Department of Energy (DOE) installations. The AAS, one of seven chartered by the EFCOG Safety Analysis Working Group, has performed an oversight function and provided direction to several technical groups. These efforts have been instrumental toward formal evaluation of computer models, improving the pedigree on high-use computer models, and development of the user-friendly Accident Analysis Guidebook (AAG). All of these improvements have improved the analytical toolkit for best complying with DOE orders and standards shaping safety analysis reports (SARs) and related documentation. Major support for these objectives has been through DOE/DP-45

Study on the experimental VHTR safety with analysis for a hypothetical rapid depressurization accident

International Nuclear Information System (INIS)

Mitake, S.; Suzuki, K.; Ohno, T.; Okada, T.

1982-01-01

A hypothetical rapid depressurization accident of the experimental VHTR has been analyzed, including all phenomena in the accident, from its initiating depressurization of the coolant to consequential radiological hazard. Based on reliability analysis of the engineered safety features, all possible sequences, in which the safety systems are in success or in failure, have been investigated with event tree analysis. The result shows the inherent safety characteristics of the reactor and the effectiveness of the engineered safety features. And through the analysis, it has been indicated that further investigations on some phenomena in the accident, e.g., air ingress by natural circulation flow and fission product transport in the plant, will bring forth more reasonable and sufficient safety of the reactor

Inroads into Equestrian Safety: Rider-Reported Factors Contributing to Horse-Related Accidents and Near Misses on Australian Roads

Directory of Open Access Journals (Sweden)

Kirrilly Thompson

2015-07-01

Full Text Available Horse riding and horse-related interactions are inherently dangerous. When they occur on public roads, the risk profile of equestrian activities is complicated by interactions with other road users. Research has identified speed, proximity, visibility, conspicuity and mutual misunderstanding as factors contributing to accidents and near misses. However, little is known about their significance or incidence in Australia. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52% reported having experienced at least one accident or near miss in the 12 months prior to the survey. Whilst our findings confirm the factors identified overseas, we also identified issues around rider misunderstanding of road rules and driver misunderstanding of rider hand signals. Of particular concern, we also found reports of potentially dangerous rider-directed road rage. We identify several areas for potential safety intervention including (1 identifying equestrians as vulnerable road users and horses as sentient decision-making vehicles (2 harmonising laws regarding passing horses, (3 mandating personal protective equipment, (4 improving road signage, (5 comprehensive data collection, (6 developing mutual understanding amongst road-users, (7 safer road design and alternative riding spaces; and (8 increasing investment in horse-related safety initiatives.

Inroads into Equestrian Safety: Rider-Reported Factors Contributing to Horse-Related Accidents and Near Misses on Australian Roads.

Science.gov (United States)

Thompson, Kirrilly; Matthews, Chelsea

2015-07-22

Horse riding and horse-related interactions are inherently dangerous. When they occur on public roads, the risk profile of equestrian activities is complicated by interactions with other road users. Research has identified speed, proximity, visibility, conspicuity and mutual misunderstanding as factors contributing to accidents and near misses. However, little is known about their significance or incidence in Australia. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey. Whilst our findings confirm the factors identified overseas, we also identified issues around rider misunderstanding of road rules and driver misunderstanding of rider hand signals. Of particular concern, we also found reports of potentially dangerous rider-directed road rage. We identify several areas for potential safety intervention including (1) identifying equestrians as vulnerable road users and horses as sentient decision-making vehicles (2) harmonising laws regarding passing horses, (3) mandating personal protective equipment, (4) improving road signage, (5) comprehensive data collection, (6) developing mutual understanding amongst road-users, (7) safer road design and alternative riding spaces; and (8) increasing investment in horse-related safety initiatives.

Flamanville plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Flamanville plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 2 parts: one part dedicated to the first 2 reactors of the plant and the second part to the EPR that is being built. Each part is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

The risk of accident in nuclear power plants - Quotes and questions. National debate on energy transition. Taking the risk of nuclear accident into account. Note to the 'scenarios' subgroup of the group of experts

International Nuclear Information System (INIS)

Laponche, Bernard

2013-01-01

After an overview of the production of electricity from nuclear energy and of its risks, the author discusses the issue of nuclear safety by distinguishing the different points of view, by describing the different levels between a severe and a major accident, and by recalling the statements made by the ASN and the IRSN on this issue. He describes the various reasons and consequences of accidents: types of accidents which could result in a core fusion, the containment failure as the major accident. He discusses the questions and comments about major issues like: strength of reactor vessels, hydrogen explosion, water vapour explosion, corium crossing the concrete sill plate, corium recovery, MOX as an aggravating situation for safety. In the last part, the author discusses the global assessment of a risk of a nuclear accident: probabilities and occurrences, significant accidents on PWRs, premonitory analysis, demonstration of nuclear safety

Development of Safety Significance Evaluation Program for Accidents and Events in NPPs

International Nuclear Information System (INIS)

Yang, Hui Chang; Hong, Seok Jin; Cho, Nam Chul; Chung, Dae Wook; Lee, Chang Joo

2010-01-01

To evaluate the significance in terms of safety for the accidents and events occurred in nuclear power plants using probabilistic safety assessment techniques can provide useful insights to the regulator. Based on the quantified risk information of accident or event occurred, regulators can decide which regulatory areas should be focused than the others. To support these regulatory analysis activities, KINS-ASP program was developed. KINS-ASP program can supports the risk increase due to the occurred accidents or events by providing the graphic interfaces and linked quantification engines for the PSA experts and non- PSA acquainted regulators both

Contributing factors in construction accidents.

Science.gov (United States)

Haslam, R A; Hide, S A; Gibb, A G F; Gyi, D E; Pavitt, T; Atkinson, S; Duff, A R

2005-07-01

This overview paper draws together findings from previous focus group research and studies of 100 individual construction accidents. Pursuing issues raised by the focus groups, the accident studies collected qualitative information on the circumstances of each incident and the causal influences involved. Site based data collection entailed interviews with accident-involved personnel and their supervisor or manager, inspection of the accident location, and review of appropriate documentation. Relevant issues from the site investigations were then followed up with off-site stakeholders, including designers, manufacturers and suppliers. Levels of involvement of key factors in the accidents were: problems arising from workers or the work team (70% of accidents), workplace issues (49%), shortcomings with equipment (including PPE) (56%), problems with suitability and condition of materials (27%), and deficiencies with risk management (84%). Employing an ergonomics systems approach, a model is proposed, indicating the manner in which originating managerial, design and cultural factors shape the circumstances found in the work place, giving rise to the acts and conditions which, in turn, lead to accidents. It is argued that attention to the originating influences will be necessary for sustained improvement in construction safety to be achieved.

Nuclear power plant safety - the risk of accidents

International Nuclear Information System (INIS)

Higson, D.; Crancher, D.W.

1975-08-01

Although it is physically impossible for any nuclear plant to explode like an atom bomb, an accidental release of radioactive material into the environment is conceivable. Three factors reduce the probability of such releases, in dangerous quantities, to an extremely low level. Firstly, there are many safety features built into the plant including a leaktight containment building to prevent the escape of such material. Secondly, the quality of engineering and standards used are far more demanding than in conventional power engineering. Thirdly, strict government licensing and regulatory control is enforced at all phases from design through construction to operation. No member of the general public is known to have been injured or died as a result of any accident to a commercial nuclear power plant. Ten workers have died as a result of over-exposure to radiation from experimental reactors and laboratory work connected with the development of nuclear plant since 1945. Because of this excellent safety record the risk of serious accidents can only be estimated. On the basis of such estimates, the chance of an accident in a nuclear power reactor which could cause a detectable increase in the incidence of radiation-induced illnesses would be less than one chance in a million per year. In a typical highly industrialised society, such as the USA, the estimated risk of an individual being killed by such accidents, from one hundred operating reactors, is no greater than one chance in sixteen million per year. There are undoubtedly risks from reactor accidents but estimates of these risks show that they are considerably less than from other activities which are accepted by society. (author)

MDEP AP1000WG Design-Specific Common Position CP-AP1000WG-02. Common position addressing Fukushima Daiichi NPP accident-related issues

International Nuclear Information System (INIS)

2016-09-01

A severe accident involving several units took place in Japan at Fukushima Daiichi nuclear power plant (NPP) in March 2011. The immediate cause of the accident was an earthquake followed by a tsunami coupled with inadequate provisions against the consequences of such events in the design. Opportunities to improve protection against a realistic design basis tsunami had not been taken. As a consequence of the tsunami, safety equipment and the related safety functions were lost at the plant, leading to core damage in three units and subsequently to large radioactive release. Several studies have already been performed to better understand the accident progression and detailed technical studies are still in progress in Japan and elsewhere. In the meantime, on-going studies on the behaviour of nuclear power plants in very severe situations, similar to Fukushima Daiichi, seek to identify potential vulnerabilities in plant design and operation; to suggest reasonably practicable upgrades; or to recommend enhanced regulatory requirements and guidance to address such situations. Likewise, agencies around the world that are responsible for regulating the design, construction and operation of AP1000 R plants are engaged in similar activities. The MDEP AP1000 R Working Group (AP1000 WG) members consist of members from Canada, China, the United Kingdom and the United States. Since the regulatory review of their AP1000 R applications have not been completed by all of these Countries yet, this paper identifies common preliminary approaches to address potential safety improvements for AP1000 R plants as related to lessons learned from the Fukushima Daiichi accident or Fukushima Daiichi-related issues. In seeking common position, regulators will provide input to this paper to reflect their safety conclusions regarding the AP1000 R design and how the design could be enhanced to address Fukushima Daiichi issues. The common preliminary approaches are organized into five sections

Issues regarding Risk Effect Analysis of Digitalized Safety Systems and Main Risk Contributors

International Nuclear Information System (INIS)

Kang, Hyun Gook; Jang, Seung-Cheol

2008-01-01

Risk factors of safety-critical digital systems affect overall plant risk. In order to assess this risk effect, a risk model of a digitalized safety system is required. This article aims to provide an overview of the issues when developing a risk model and demonstrate their effect on plant risk quantitatively. Research activities in Korea for addressing these various issues, such as the software failure probability and the fault coverage of self monitoring mechanism are also described. The main risk contributors related to the digitalized safety system were determined in a quantitative manner. Reactor protection system and engineered safety feature component control system designed as part of the Korean Nuclear I and C System project are used as example systems. Fault-tree models were developed to assess the failure probability of a system function which is designed to generate an automated signal for actuating both of the reactor trip and the complicated accident-mitigation actions. The developed fault trees were combined with a plant risk model to evaluate the effect of a digitalized system's failure on the plant risk. (authors)

AESJ 5 years activities and issues to be solved for the TEPCO's Fukushima Daiichi accident

International Nuclear Information System (INIS)

Uetsuka, Hiroshi; Yamamoto, Akio; Saso, Michitaka

2016-01-01

This paper summarizes the measures taken by the Atomic Energy Society of Japan (AESJ) against the Fukushima Daiichi Accident, and its challenges to the task to be addressed in the future. As recommendations by AESJ, the following five items were pointed out in its final report on the survey on the accident: (1) basic matters on nuclear safety, (2) matters on direct causes of accident, (3) organizational matters among background factors, (4) collective matters, and (5) future matters related to environmental remediation. As the commitment to the Fukushima reconstruction, AESJ performed the introduction of decontamination technologies, hosting of interactive forum and symposium session in Fukushima Prefecture, decontamination test of paddy fields, and preparation of an air dose rate map in Fukushima Prefecture. As for the decommissioning of the Fukushima Daiichi Nuclear Power Station, AESJ prepared guidelines by applying probabilistic risk assessment (PRA) to tsunami, and revised seismic PRA standards. Since there was a lack in the implementation of multiple protections as one of the background causes of the Fukushima Accident, it summarized 'concept of the implementation of multiple protections.' In addition, it surveyed and examined the accident from the viewpoint of human factors, discussed the importance of accident investigation from the viewpoint of a party in charge, and issued a report. (A.O.)

Continued efforts to improve the robustness of the French Gen II PWRs with respect to the risk of severe accidents. Safety assessment and research activities

International Nuclear Information System (INIS)

Raimond, E.; Bonnet, J.M.; Generino, G.; Dubreuil, M.; Pichereau, F.; Van Dorsselaere, J.P.

2012-01-01

In the context of post Fukushima accident, the paper presents the continuous efforts performed in France to upgrade progressively the French Gen II pressurised water reactors safety features in order to face the risks of any severe accident. It reminds some decisions taken after the TMI2 and the Chernobyl accidents and describes the situation in France before the Fukushima accident: -) progress done on severe accident consequences analysis thanks to recent research activities, -) improvement of Gen II PWRs safety features, in relation with the periodic safety review process, -) definition of higher safety levels requirement directly linked to the protection of population in the framework of Gen II PWRs long term operation. The last part of the paper comments carefully how the Fukushima accident will interfere on all these previous efforts to increase the Gen II PWRs robustness. The Fukushima accident clearly highlights a need of additional efforts to identify possible cliff edge effect in case of beyond design events (especially external events). The definition of additional accident management procedures and means to secure a reactor (or a site) whatever the conditions will be a major consequence for the French NPPs. In a second step, some complements on the existing defense-in-depth approach are now expected: additional requirements to define line of defense against adverse consequences of beyond design situations. The need for specific additional research activities after the Fukushima accident seems to be limited to some specific issues (for example spent fuel pool behaviour in case of long term loss of cooling). This paper is followed by the slides of the presentation

Analysis of some accident conditions in confirmation of the HTGR safety

Energy Technology Data Exchange (ETDEWEB)

Grebennik, V. N.; Grishanin, E. I.; Kukharkin, N. E.; Mikhailov, P. V.; Pinchuk, V. V.; Ponomarev-Stepnoy, N. N.; Fedin, G. I.; Shilov, V. N.; Yanushevich, I. V. [Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Moscow. Inst. Atomnoj Ehnergii

1981-01-15

This report concerns some accident conditions for the HTGR-50 demonstrational reactor which along with the safety features common to the typical HTGR differs in design. The analyses carried out on the accident situations showed that due to the high heat capacity of the graphite core and negative temperature effect of the reactivity the HTGR-50 reactor is effectively selfcontrolled at different perturbations of the reactivity and has low sensitivity to the failure of the core cooling. The primary circuit depressurization accident should be thoroughly studied because of the dangerous consequences i.e. the core overheating and the reactivity release into the environment. As a whole, the studies now in progress show that the problem of the HTGR safety can be successfully solved.

Analysis of some accident conditions in confirmation of the HTGR safety

International Nuclear Information System (INIS)

Grebennik, V.N.; Grishanin, E.I.; Kukharkin, N.E.; Mikhailov, P.V.; Pinchuk, V.V.; Ponomarev-Stepnoy, N.N.; Fedin, G.I.; Shilov, V.N.; Yanushevich, I.V.

1981-01-01

This report concerns some accident conditions for the HTGR-50 demonstrational reactor which along with the safety features common to the typical HTGR differs in design. The analyses carried out on the accident situations showed that due to the high heat capacity of the graphite core and negative temperature effect of the reactivity the HTGR-50 reactor is effectively selfcontrolled at different perturbations of the reactivity and has low sensitivity to the failure of the core cooling. The primary circuit depressurization accident should be thoroughly studied because of the dangerous consequences i.e. the core overheating and the reactivity release into the environment. As a whole, the studies now in progress show that the problem of the HTGR safety can be successfully solved

Saint-Laurent-des-Eaux plant - Report on the complementary safety assessment of nuclear facilities in the light of the Fukushima accident

International Nuclear Information System (INIS)

2011-01-01

This CSA (Complementary Safety Assessment) analyses the robustness of the Saint-Laurent-des-Eaux plant to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. Robustness is the ability for the plant to withstand events beyond the level for which the plant was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence. Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like EDF's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. The creation of a nuclear rapid action force (FARN) is proposed: this will be a national emergency force made up of specialized teams equipped to intervene in less than 24 hours on a nuclear site hit by an accident. This report is divided into 8 main chapters: 1) features of the site, 2) earthquake risk, 3) flooding risk, 4) risks due to other extreme natural disasters, 5) the loss of electrical power supplies and of heat sink, 6) management of severe accidents (accidents with core melt), 7) task subcontracting policy, 8) synthesis and list of improvements. 4 following appendices review: EDF's crisis organization, the FARN, radiation protection organization and accidental event trees. (A.C.)

77 FR 10666 - Pipeline Safety: Post Accident Drug and Alcohol Testing

Science.gov (United States)

2012-02-23

... 199 [Docket No. PHMSA-2011-0335] Pipeline Safety: Post Accident Drug and Alcohol Testing AGENCY... operators of Liquefied Natural Gas (LNG) facilities to conduct post- accident drug and alcohol tests of..., operators must drug and alcohol test each covered employee whose performance either contributed to the...

Safety upgrading activities against tsunami, earthquake, and severe accident at Hamaoka NPPs

International Nuclear Information System (INIS)

Watanabe, Tetsuya; Wakunaga, Takao; Ishida, Takahisa

2013-01-01

As the lessons learned by the Fukushima Daiichi NPPs accident, Chubu Electric Power carried out the Emergency Safety Measures at Hamaoka NPPs immediately, and announced the plan for tsunami countermeasures including the construction of 18m-height tsunami protection wall in July 2011. Furthermore, the company announced the additional severe accident and tsunami countermeasures, and etc. in December 2012 and in April 2013, such as the installation of Filtered Containment Venting System and increasing the height of the tsunami protection wall from 18m to 22m. In this paper, we present major safety upgrading activities against tsunami, earthquake and severe accident at Hamaoka NPPs. (author)

A system of safety management practices and worker engagement for reducing and preventing accidents: an empirical and theoretical investigation.

Science.gov (United States)

Wachter, Jan K; Yorio, Patrick L

2014-07-01

The overall research objective was to theoretically and empirically develop the ideas around a system of safety management practices (ten practices were elaborated), to test their relationship with objective safety statistics (such as accident rates), and to explore how these practices work to achieve positive safety results (accident prevention) through worker engagement. Data were collected using safety manager, supervisor and employee surveys designed to assess and link safety management system practices, employee perceptions resulting from existing practices, and safety performance outcomes. Results indicate the following: there is a significant negative relationship between the presence of ten individual safety management practices, as well as the composite of these practices, with accident rates; there is a significant negative relationship between the level of safety-focused worker emotional and cognitive engagement with accident rates; safety management systems and worker engagement levels can be used individually to predict accident rates; safety management systems can be used to predict worker engagement levels; and worker engagement levels act as mediators between the safety management system and safety performance outcomes (such as accident rates). Even though the presence of safety management system practices is linked with incident reduction and may represent a necessary first-step in accident prevention, safety performance may also depend on mediation by safety-focused cognitive and emotional engagement by workers. Thus, when organizations invest in a safety management system approach to reducing/preventing accidents and improving safety performance, they should also be concerned about winning over the minds and hearts of their workers through human performance-based safety management systems designed to promote and enhance worker engagement. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Inherent safety features of the HTTR revealed in the accident condition

International Nuclear Information System (INIS)

Kunitomi, K.; Shinozaki, M.; Baba, O.; Saito, S.

1992-01-01

The High Temperature Engineering Test Reactor (HTTR) being constructed by JAERI (Japan Atomic Energy Research Institute) is a graphite-moderated and helium-cooled reactor with an outlet gas temperature of 950degC. The inherent safety characteristics in the HTTR prevent temperature increase of reactor fuels and fission product release from the reactor core in postulated accident conditions. The reactor core can be cooled by a Vessel Cooling System (VCS) indirectly, even in the case that no forced cooling is expected during the accident such as primary pipe break. The VCS consists of independent water cooling loop and cooling panel around the reactor pressure vessel. The cooling panel whose temperature of 60-90degC cools the reactor pressure vessel by radiation and removes the decay heat from the core indirectly. Furthermore, even if failure of VCS is assumed during this accident as a severe accident, the reactor core is remained safe despite the temperature increase of biological concrete shield around the reactor pressure vessel. This paper describes the inherent safety features of the HTTR specially focused on the accident condition without forced cooling. The detailed analytical results of such an accident are described together with clarifying the role of the VCS. (author)

An analysis on human factor issues in criticality accident at a uranium processing plant. Investigation on human behavior contributing to the criticality accident. Interim report

International Nuclear Information System (INIS)

Sasou, Kuonihide; Goda, Hideki; Hirotsu, Yuko

1999-01-01

At 10:30 am, September 30th, 1999, a criticality accident occurred in a conversion building of a uranium processing plant in Tokai, Ibaraki prefecture. 69 people including 3 workers who then worked at the building, 3 fire fighters who dispatched to rescue them were exposed to the radiation. People with a 350 m-radius of the site were recommended to evacuate themselves from the region to a temporarily prepared evacuation center. And about one hundred thousand people within a 10 km-radius were also advised to stay inside of their home. Nuclear Safety Commission's Accident Investigation Committee is investigating causes of this accident and have been revealing that deviation from government-authorized processing method and negligence of its illegal procedure had contributed to the accident. The influence of this accident is expanding not only to the plant operating company, local people but also to Japanese nuclear power policy, the whole nuclear industry in Japan. Especially pervasion of 'Safety Culture' is strongly being required. This report analyses latent factors of some human behavior directly contributing to the criticality accident. It also mentions that 4 critical points on the poor climate for safety in the work place, the inadequate safety management, the unsuitable equipment and the production-biased company's policy are the latent factors of this accident. It also finds that the poor climate and the production-biased policy are the most important factors. It can be said that some people directly or indirectly having caused the accident are the victims of them. (author)

Regulatory analysis for resolution of USI [Unresolved Safety Issue] A-47

International Nuclear Information System (INIS)

Szukiewicz, A.J.

1989-07-01

This report presents a summary of the regulatory analysis conducted by the US Nuclear Regulatory Commission staff to evaluate the value/impact of alternatives for the resolution of Unresolved Safety Issue A-47, ''Safety Implications of Control Systems.'' The NRC staff's resolution presented herein is based on these analyses and on the technical findings and conclusions presented in NUREG-1217, the companion document to this report. The staff has concluded that certain actions should be taken to improve safety in light-water reactor plants. The staff recommended that certain plants improve their control systems to preclude reactor vessel/steam generator overfill events and to prevent steam generator dryout, modify their technical specifications to verify operability of such systems, and modify selected emergency procedures to ensure safe shutdown of the plant following a small-break loss-of-coolant accident. This report was issued as a draft for public comment on May 27, 1988. As a result of the public comments received, this report was revised. The NRC staff's responses to and resolution of the public comments are included as Appendix C to the final report, NUREG-1217

IAEA Issues Report on Mission to Review Japan's Nuclear Power Plant Safety Assessment Process

International Nuclear Information System (INIS)

2012-01-01

Full text: A team of international nuclear safety experts has delivered its report on a mission it conducted from 21-31 January 2012 to review Japan's process for assessing nuclear safety at the nation's nuclear power plants. International Atomic Energy Agency (IAEA) officials delivered the IAEA Mission Report to Japanese officials yesterday and made it publicly available today. Following the 11 March 2011 accident at TEPCO's Fukushima Daiichi Nuclear Power Station, Japan's Nuclear and Industrial Safety Agency (NISA) announced the development of a revised safety assessment process for the nation's nuclear power reactors. At the request of the Government of Japan, the IAEA organized a team of five IAEA and three international nuclear safety experts and visited Japan to review NISA's approach to the Comprehensive Assessments for the Safety of Existing Power Reactor Facilities and how NISA examines the results submitted by nuclear operators. A Preliminary Summary Report was issued on 31 January. 'The mission report provides additional information regarding the team's recommendations and overall finding that NISA's instructions to power plants and its review process for the Comprehensive Safety Assessments are generally consistent with IAEA Safety Standards', said team leader James Lyons, Director of the IAEA's Nuclear Installation Safety Division. National safety assessments and their peer review by the IAEA are a key component of the IAEA Action Plan on Nuclear Safety, which was approved by the Agency's Member States following last year's nuclear accident at Fukushima Daiichi Nuclear Power Station. The IAEA safety review mission held meetings in Tokyo with officials from NISA, the Japanese Nuclear Energy Safety Organization (JNES), and the Kansai Electric Power Company (KEPCO), and the team visited the Ohi Nuclear Power Station to see an example of how Japan's Comprehensive Safety Assessment is being implemented by nuclear operators. In its report delivered today

Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Appendix I. Accident definition and use of event trees

International Nuclear Information System (INIS)

1975-10-01

Information is presented concerning accident definition and use of event trees, event tree methodology, potential accidents covered by the reactor safety study, analysis of potential accidents involving the reactor core, and analysis of potential accidents not involving the core

Aircraft accident analysis for emergency planning and safety analysis

International Nuclear Information System (INIS)

Nicolosi, S.L.; Jordan, H.; Foti, D.; Mancuso, J.

1996-01-01

Potential aircraft accidents involving facilities at the Rocky Flats Environmental Technology Site (Site) are evaluated to assess their safety significance. This study addresses the probability and facility penetrability of aircraft accidents at the Site. The types of aircraft (large, small, etc.) that may credibly impact the Site determine the types of facilities that may be breached. The methodology used in this analysis follows elements of the draft Department of Energy Standard ''Accident Analysis for Aircraft Crash into Hazardous Facilities'' (July 1995). Key elements used are: the four-factor frequency equation for aircraft accidents; the distance criteria for consideration of airports, airways, and jet routes; the consideration of different types of aircraft; and the Modified National Defense Research Committee (NDRC) formula for projectile penetration, perforation, and minimum resistant thickness. The potential aircraft accident frequency for each type of aircraft applicable to the Site is estimated using a four-factor formula described in the draft Standard. The accident frequency is the product of the annual number of operations, probability of an accident, probability density function, and area. The annual number of operations is developed from site-specific and state-wide data

Questions concerning safety and risk after the nuclear accidents in Japan. Deepened accident analysis for the Fukushima Daiichi power plant; Sicherheits- und Risikofragen im Nachgang zu den nuklearen Stoer- und Unfaellen in Japan. Vertiefte Ereignisanalyse zur Anlage Fukushima-Daini

Energy Technology Data Exchange (ETDEWEB)

Pistner, Christoph; Englert, Matthias [Oeko-Institut e.V. - Institut fuer Angewandte Oekologie, Darmstadt (Germany)

2015-02-25

The study questions concerning safety and risk in Japanese power plants following the disastrous nuclear accident covers the following issues: the nuclear facility Fukushima Daiichi, site characterization, important technical equipment, important electro-technical equipment, personal; description of the accident progression in the Fukushima nuclear power plant: impact of the earthquake, impact of the tsunami, short-term measures of the operating personnel, pressure and temperature situation in the containments, restoration of the after-heat cooling system in the units 1/2 and 4, fuel element storage pool, summarized parameters during the accident progress; comparative analysis of the accident progression at the Fukushima Daiichi site.

International Experts’ Meeting on Reactor and Spent Fuel Safety in the Light of the Accident at the Fukushima Daiichi Nuclear Power Plant. Presentations

International Nuclear Information System (INIS)

2012-01-01

The primary objectives of this International Experts’ Meeting (IEM) were: to analyse relevant technical aspects of reactor and spent nuclear fuel management safety and performance related to severe accidents; to review what is known to date about the accident at the Fukushima Daiichi nuclear power plant in order to understand more fully its root causes; and to share the lessons learned from the accident. The meeting identified the necessary priorities for further actions in these areas in different power reactor types, focusing in particular on boiling water reactors (BWRs) and pressurized water reactors (PWRs). The meeting provided a forum for discussions and exchange of information among technical experts from Member States on reactor and spent nuclear fuel safety and performance under severe conditions. The meeting was of particular interest to technical experts from utilities, research and design organizations, regulatory bodies, manufacturing and service companies and other stakeholders. In particular, the objectives of the meeting was to: • Identify and analyse reactor and spent nuclear fuel safety and performance issues; • Consider the design, engineering and analysis of current and new systems for accident prevention and mitigation; • Exchange information on national assessments of reactor and spent nuclear fuel safety and performance; and • Identify potential priority areas for research and development, technology development and management

Role of the man-machine interface in accident management strategies

International Nuclear Information System (INIS)

Oewre, Fridtjov

2001-01-01

First, this paper gives a short general review on important safety issues in the field of man-machine interaction as expressed by important nuclear safety organisations. Then follows a summary discussion on what constitutes a modern Man-Machine Interface (MMI) and what is normally meant with accident management and accident management strategies. Furthermore, the paper focuses on three major issues in the context of accident management. First, the need for reliable information in accidents and how this can be obtained by additional computer technology. Second, the use of procedures is discussed, and basic MMI aspects of computer support for procedure presentation are identified followed by a presentation of a new approach on how to computerise procedures. Third, typical information needs for characteristic end-users in accidents, such as the control room operators, technical support staff and plant emergency teams, is discussed. Some ideas on how to apply virtual reality technology in accident management is also presented

Safety analysis of RA reactor operation, I-III, Part II, Accident analysis

International Nuclear Information System (INIS)

Raisic, N.

1963-02-01

This volume covers the analyses of two types of accidents: accidents caused by uncontrolled reactivity increase, and accidents caused by decrease or loss of cooling. First type of accidents, uncontrolled reactivity insertion could occur due to removal of compensation, regulatory or safety rods, or by increase of heavy water level. Removal of irradiated samples from the core could also cause increase of reactivity. Second type of accidents could occur due to interruption of cooling, loss of water in the secondary cooling loop or loss of water in the primary coolant loop

Aviation Safety Program: Weather Accident Prevention (WxAP) Project Overview and Status

Science.gov (United States)

Nadell, Shari-Beth

2003-01-01

This paper presents a project overview and status for the Weather Accident Prevention (WxAP) aviation safety program. The topics include: 1) Weather Accident Prevention Project Background/History; 2) Project Modifications; 3) Project Accomplishments; and 4) Project's Next Steps.

Radiological protection, safety and security issues in the industrial and medical applications of radiation sources

International Nuclear Information System (INIS)

Vaz, Pedro

2015-01-01

The use of radiation sources, namely radioactive sealed or unsealed sources and particle accelerators and beams is ubiquitous in the industrial and medical applications of ionizing radiation. Besides radiological protection of the workers, members of the public and patients in routine situations, the use of radiation sources involves several aspects associated to the mitigation of radiological or nuclear accidents and associated emergency situations. On the other hand, during the last decade security issues became burning issues due to the potential malevolent uses of radioactive sources for the perpetration of terrorist acts using RDD (Radiological Dispersal Devices), RED (Radiation Exposure Devices) or IND (Improvised Nuclear Devices). A stringent set of international legally and non-legally binding instruments, regulations, conventions and treaties regulate nowadays the use of radioactive sources. In this paper, a review of the radiological protection issues associated to the use of radiation sources in the industrial and medical applications of ionizing radiation is performed. The associated radiation safety issues and the prevention and mitigation of incidents and accidents are discussed. A comprehensive discussion of the security issues associated to the global use of radiation sources for the aforementioned applications and the inherent radiation detection requirements will be presented. Scientific, technical, legal, ethical, socio-economic issues are put forward and discussed. - Highlights: • The hazards associated to the use of radioactive sources must be taken into account. • Security issues are of paramount importance in the use of radioactive sources. • Radiation sources can be used to perpetrate terrorist acts (RDDs, INDs, REDs). • DSRS and orphan sources trigger radiological protection, safety and security concerns. • Regulatory control, from cradle to grave, of radioactive sources is mandatory.

European community light water reactor safety research projects. Experimental issue

International Nuclear Information System (INIS)

1975-01-01

Research programs on light water reactor safety currently carried out in the European Community are presented. They cover: accident conditions (LOCA, ECCS, core meltdown, external influences, etc...), fault and accident prevention and means of mitigation, normal operation conditions, on and off site implications and equipment under severe accident conditions, and miscellaneous subjects

Hydrogen-control systems for severe LWR accident conditions - a state-of-technology report

International Nuclear Information System (INIS)

Hilliard, R.K.; Postma, A.K.; Jeppson, D.W.

1983-03-01

This report reviews the current state of technology regarding hydrogen safety issues in light water reactor plants. Topics considered in this report relate to control systems and include combustion prevention, controlled combustion, minimization of combustion effects, combination of control concepts, and post-accident disposal. A companion report addresses hydrogen generation, distribution, and combustion. The objectives of the study were to identify the key safety issues related to hydrogen produced under severe accident conditions, to describe the state of technology for each issue, and to point out ongoing programs aimed at resolving the open issues

Importance of LWR best-estimate safety calculations for analysis of Fukushima-like accidents

International Nuclear Information System (INIS)

Sanchez Espinoza, V.; Ivanov, K.

2011-01-01

The safety assessment of nuclear power plants relies heavily on numerical simulations, which must include the most important physical models that are representative for the reactor type of interest. The current trends in nuclear power generation and regulation are to perform safety studies by 'best-estimate' codes that allow a realistic modeling of nuclear and thermal-hydraulic processes of the reactor core and the entire plant behavior including control and protection functions. Realistic methods are referred to as 'best-estimate' calculations, implying that they use a set of data, correlations, and methods designed to represent the phenomena, using the best available techniques. The application of best-estimate methodologies in the licensing process requires the quantification of the embedded uncertainties of the used codes. In this field many international initiatives are underway under the umbrella of the OECD such as the Light Water Reactor Uncertainty Analysis in Modeling benchmark, Oskarshamn 2 Boiling Water Reactor (BWR) Stability benchmark, Kalinin-3 VVER-1000 benchmark, etc. that underlies the importance of these issues. The Fukushima accident has shown the importance of the knowledge of the initial phase of the accident regarding the state of the core, in-vessel structures, and containment as well as the amount of fissile material inventories that potentially can be released if the safety barriers fail. For the development of mitigation and prevention measures modeling of the sequence of the events along with understanding of the key physical phenomena driving the accident progression is important. The paper presents the best-estimate coupled methodologies implemented, validated and applied at the Karlsruhe Institute Technology (KIT) for both types of LWRs - Pressurized Water Reactors (PWRs) and BWRs. Example are given with a BWR steady state and transient simulations along with corresponding uncertainty quantification. The on-going development of high

Analysis of accidents in uranium mines and suggestions on safety in production

International Nuclear Information System (INIS)

Xue Shiqian.

1989-01-01

The serious and fatal accidents happening in the uranium mines in China are descibed and analysed based on the classification, cause, age of the dead and economic losses brought by the accidents. The suggestions on safety in production are also presented

Discussion on several issues of the accidents management of nuclear power plants in operation

International Nuclear Information System (INIS)

Cao Xuewu; Wang Zhe; Zhang Yingzhen

2009-01-01

This article discusses several issues of the accident management of nuclear power plants in operation, for example: the necessity, implementation principle of accident management and accident management program etc. For conducting accident management for beyond design basis accidents, this article thinks that the accident management program should be developed and implemented to ensure that the plant and its personnel with responsibilities for accident management are adequately prepared to take effective on-site actions to prevent or mitigate the consequences of severe accident. (authors)

Twenty-fifth water reactor safety information meeting: Proceedings. Volume 1: Plenary sessions; Pressure vessel research; BWR strainer blockage and other generic safety issues; Environmentally assisted degradation of LWR components; Update on severe accident code improvements and applications

Energy Technology Data Exchange (ETDEWEB)

Monteleone, S. [comp.] [Brookhaven National Lab., Upton, NY (United States)

1998-03-01

This three-volume report contains papers presented at the conference. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Japan, Norway, and Russia. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. This volume contains the following information: (1) plenary sessions; (2) pressure vessel research; (3) BWR strainer blockage and other generic safety issues; (4) environmentally assisted degradation of LWR components; and (5) update on severe accident code improvements and applications. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

Twenty-fifth water reactor safety information meeting: Proceedings. Volume 1: Plenary sessions; Pressure vessel research; BWR strainer blockage and other generic safety issues; Environmentally assisted degradation of LWR components; Update on severe accident code improvements and applications

International Nuclear Information System (INIS)

Monteleone, S.

1998-03-01

This three-volume report contains papers presented at the conference. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Japan, Norway, and Russia. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. This volume contains the following information: (1) plenary sessions; (2) pressure vessel research; (3) BWR strainer blockage and other generic safety issues; (4) environmentally assisted degradation of LWR components; and (5) update on severe accident code improvements and applications. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database

Preventing marine accidents caused by technology-induced human error

OpenAIRE

Bielić, Toni; Hasanspahić, Nermin; Čulin, Jelena

2017-01-01

The objective of embedding technology on board ships, to improve safety, is not fully accomplished. The paper studies marine accidents caused by human error resulting from improper human-technology interaction. The aim of the paper is to propose measures to prevent reoccurrence of such accidents. This study analyses the marine accident reports issued by Marine Accidents Investigation Branch covering the period from 2012 to 2014. The factors that caused these accidents are examined and categor...

Classification Of Road Accidents From The Perspective Of Vehicle Safety Systems

Directory of Open Access Journals (Sweden)

Jirovský Václav

2015-11-01

Full Text Available Modern road accident investigation and database structures are focused on accident analysis and classification from the point of view of the accident itself. The presented article offers a new approach, which will describe the accident from the point of view of integrated safety vehicle systems. Seven main categories have been defined to specify the level of importance of automated system intervention. One of the proposed categories is a new approach to defining the collision probability of an ego-vehicle with another object. This approach focuses on determining a 2-D reaction space, which describes all possible positions of the vehicle or other moving object in the specified amount of time in the future. This is to be used for defining the probability of the vehicles interacting - when the intersection of two reaction spaces exists, an action has to be taken on the side of ego-vehicle. The currently used 1-D quantity of TTC (time-to-collision can be superseded by the new reaction space variable. Such new quantity, whose basic idea is described in the article, enables the option of counting not only with necessary braking time, but mitigation by changing direction is then easily feasible. Finally, transparent classification measures of a probable accident are proposed. Their application is highly effective not only during basic accident comparison, but also for an on-board safety system.

Accidents in industrial radiography and lessons to be learned. A review of IAEA Safety Report

International Nuclear Information System (INIS)

Modupe, M.S.; Oresegun, O.

1998-01-01

This IAEA Safety Report Series publication is the result of a review of a large selection of accidents in industrial radiography which Regulatory Authorities, professional associations and scientific journals have reported. The review's objective was to draw lessons from the initiating events of the accidents, contributing factors and the consequences. A small, representative selection of accident descriptions is used to illustrate the primary causes of radiography accidents and a set of recommendations to prevent recurrence of such accidents or to mitigate the consequences of those that do occur is provided. By far the most common primary cause of over-exposure was 'Failure to follow operational procedures' and specifically failure to perform radiation monitoring to locate the position of the source. The information in the Safety Report is intended for use by Regulatory Authorities, operating organizations, workers manufacturers and client organizations having responsibilities for radiation protection and safety in industrial radiography. (author)

Technical Issues and Proposes on the Legislation of Probabilistic Safety Assessment in Periodic Safety Review

International Nuclear Information System (INIS)

Hwang, Seok-Won; Jeon, Ho-Jun; Na, Jang-Hwan

2015-01-01

Korean Nuclear Power Plants have performed a comprehensive safety assessment reflecting design and procedure changes and using the latest technology every 10 years. In Korea, safety factors of PSR are revised to 14 by revision of IAEA Safety Guidelines in 2003. In the revised safety guidelines, safety analysis field was subdivided into deterministic safety analysis, PSA (Probabilistic safety analysis), and hazard analysis. The purpose to examine PSA as a safety factor on PSR is to make sure that PSA results and assumptions reflect the latest state of NPPs, validate the level of computer codes and analytical models, and evaluate the adequacy of PSA instructions. In addition, its purpose is to derive the plant design change, operating experience of other plants and safety enhancement items as well. In Korea, PSA is introduced as a new factor. Thus, the overall guideline development and long-term implementation strategy are needed. Today in Korea, full-power PSA model revision and low-power and shutdown (LPSD) PSA model development is being performed as a part of the post Fukushima action items for operating plants. The scope of the full-power PSA is internal/external level 1, 2 PSA. But in case of fire PSA, the scope is level 1 PSA using new method, NUREG/CR-6850. In case of LPSD PSA, level 1 PSA for all operating plants, and level 2 PSA for 2 demonstration plants are under development. The result of the LPSD PSA will be used as major input data for plant specific SAMG (Severe Accident Management Guideline). The scope of PSA currently being developed in Korea cannot fulfill 'All Mode, All Scope' requirements recommended in the IAEA Safety Guidelines. Besides the legislation of PSA, step-by-step development strategy for non-performed scopes such as level 3 PSA and new fire PSA is one of the urgent issues in Korea. This paper suggests technical issues and development strategies for each PSA technical elements.

Proceedings of the international topical meeting on advanced reactors safety: Volume 2

International Nuclear Information System (INIS)

1997-01-01

In this volume, 89 papers are grouped under the following headings: advances in research/test reactor safety; advanced reactor accident management and emergency actions; advanced reactors instrumentation/controls/human factors; probabilistic risk/safety and reliability assessments; steam explosion research and issues; advanced reactor severe accident issues and research (analysis and assessments); advanced reactor thermal hydraulics; accelerator-driven source safety; liquid-metal reactor safety; structural assessments and issues; late papers

Considerations on monitoring needs of advanced, passive safety light water reactors for severe accident management

International Nuclear Information System (INIS)

Bava, G.; Zambardi, F.

1992-01-01

This paper deals with problems concerning information and related instrumentation needs for Accident Management (AM), with special emphasis on Severe Accidents (SA) in the new advanced, passive safety Light Water Reactors (PLWR), presently in a development stage. The passive safety conception adopted in the plants concerned goes parallel with a deeper consideration of SA, that reflects the need of increasing the plant resistance against conditions going beyond traditional ''design basis accidents''. Further, the role of Accident Management (AM) is still emphasized as last step of the defence in depth concept, in spite of the design efforts aimed to reduce human factor importance; as a consequence, the availability of pertinent information on actual plant conditions remains a necessary premise for performing preplanned actions. This information is essential to assess the evolution of the accident scenarios, to monitor the performances of the safety systems, to evaluate the ultimate challenge to the plant safety, and to implement the emergency operating procedures and the emergency plans. Based on these general purposes, the impact of the new conception on the monitoring structure is discussed, furthermore reference is made to the accident monitoring criteria applied in current plants to evaluate the requirements for possible solutions. (orig.)

Safety Climate and Occupational Stress According to Occupational Accidents Experience and Employment Type in Shipbuilding Industry of Korea.

Science.gov (United States)

Kim, Kyung Woo; Park, Sung Jin; Lim, Hae Sun; Cho, Hm Hak

2017-09-01

Safety climate and occupational stress are related with occupational accident. The present study tried to identify the differences in safety climate and occupational stress according to occupational accidents experience and employment type (e.g., direct workers and subcontract workers). In this study, we conducted a survey using safety climate scale and Korean Occupational Stress Scale and classified the participants into four groups: direct workers working for accident-free departments, direct workers working for accident departments, subcontract workers working for accident-free departments, and subcontract workers working for accident departments for 2 years within the same workplace in the shipbuilding industry. The direct workers and subcontract workers showed diverse results in subscales of safety climate and occupational stress. This result is supported by existing studies; however, further study is necessary for more supporting evidence and elaborative methodological approach. The necessity of management for safety climate and psychosocial factor such as occupational stress for both direct workers and subcontract workers as a whole is suggested by this study.

NIF: Impacts of chemical accidents and comparison of chemical/radiological accident approaches

International Nuclear Information System (INIS)

Lazaro, M.A.; Policastro, A.J.; Rhodes, M.

1996-01-01

The US Department of Energy (DOE) proposes to construct and operate the National Ignition Facility (NIF). The goals of the NIF are to (1) achieve fusion ignition in the laboratory for the first time by using inertial confinement fusion (ICF) technology based on an advanced-design neodymium glass solid-state laser, and (2) conduct high-energy-density experiments in support of national security and civilian applications. The primary focus of this paper is worker-public health and safety issues associated with postulated chemical accidents during the operation of NIF. The key findings from the accident analysis will be presented. Although NIF chemical accidents will be emphasized, the important differences between chemical and radiological accident analysis approaches and the metrics for reporting results will be highlighted. These differences are common EIS facility and transportation accident assessments

Global ship accidents and ocean swell-related sea states

Directory of Open Access Journals (Sweden)

Z. Zhang

2017-11-01

Full Text Available With the increased frequency of shipping activities, navigation safety has become a major concern, especially when economic losses, human casualties and environmental issues are considered. As a contributing factor, the sea state plays a significant role in shipping safety. However, the types of dangerous sea states that trigger serious shipping accidents are not well understood. To address this issue, we analyzed the sea state characteristics during ship accidents that occurred in poor weather or heavy seas based on a 10-year ship accident dataset. Sea state parameters of a numerical wave model, i.e., significant wave height, mean wave period and mean wave direction, were analyzed for the selected ship accident cases. The results indicated that complex sea states with the co-occurrence of wind sea and swell conditions represent threats to sailing vessels, especially when these conditions include similar wave periods and oblique wave directions.

Global ship accidents and ocean swell-related sea states

Science.gov (United States)

Zhang, Zhiwei; Li, Xiao-Ming

2017-11-01

With the increased frequency of shipping activities, navigation safety has become a major concern, especially when economic losses, human casualties and environmental issues are considered. As a contributing factor, the sea state plays a significant role in shipping safety. However, the types of dangerous sea states that trigger serious shipping accidents are not well understood. To address this issue, we analyzed the sea state characteristics during ship accidents that occurred in poor weather or heavy seas based on a 10-year ship accident dataset. Sea state parameters of a numerical wave model, i.e., significant wave height, mean wave period and mean wave direction, were analyzed for the selected ship accident cases. The results indicated that complex sea states with the co-occurrence of wind sea and swell conditions represent threats to sailing vessels, especially when these conditions include similar wave periods and oblique wave directions.

Safety issues related to the intermediate heat storage for the EU DEMO

Energy Technology Data Exchange (ETDEWEB)

Carpignano, Andrea [NEMO group, Dipartimento Energia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Pinna, Tonio [ENEA, 00044 Frascati (Italy); Savoldi, Laura; Sobrero, Giulia; Uggenti, Anna Chiara [NEMO group, Dipartimento Energia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Zanino, Roberto, E-mail: roberto.zanino@polito.it [NEMO group, Dipartimento Energia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy)

2016-11-01

Highlights: • IHS affects only the PHTS and the BoP (Balance of Plant). • PIEs list does not change but IHS influences PIEs evolution. • Additional issues to be addressed in PIEs study due to the implementation of HIS. • No safety/operational major obstacles were found for IHS concept. - Abstract: The functional deviations able to compromise system safety in the EU DEMO Primary Heat Transfer System (PHTS) with intermediate heat storage (IHS) based on molten salts are identified and compared to the deviations identified with PHTS without IHS. The resulting safety issues for the Balance of Plant (BoP) have been taken into account. Functional Failure Mode and Effects Analysis (FFMEA) is used to highlight the Postulated Initiating Events (PIE) of incident/accident sequences and to provide some safety insights during the preliminary design. The architecture of the system with IHS does not introduce new PIE with respect to the case without IHS, but it modifies some of them. In particular the two Postulated Initiating Events that are affected by the presence of IHS are the LOCA in the tubes of the HX between primary and intermediate circuit and the loss of heat sink for the first wall or the breeding zone. In fact the IHS introduces some advantages concerning the stability of the secondary circuit, but some weaknesses are associated to the physical-chemical nature of molten salts, especially oxidizing power, corrosive nature and risk of solidification. These issues can be managed in the design by the introduction of new safety functions.

Links between operating experience feedback of industrial accidents and nuclear safety

International Nuclear Information System (INIS)

Eury, S.P.

2012-01-01

Since 1992, the bureau for analysis of industrial risks and pollutions (BARPI) collects, analyzes and publishes information on industrial accidents. The ARIA database lists over 40.000 accidents or incidents, most of which occurred in French classified facilities (ICPE). Events occurring in nuclear facilities are rarely reported in ARIA because they are reported in other databases. This paper describes the process of selection, characterization and review of these accidents, as well as the following consultation with industry trade groups. It is essential to publicize widely the lessons learned from analyzing industrial accidents. To this end, a web site (www.aria.developpement-durable.gouv.fr) gives free access to the accidents summaries, detailed sheets, studies, etc. to professionals and the general public. In addition, the accidents descriptions and characteristics serve as inputs to new regulation projects or risk analyses. Finally, the question of the links between operating experience feedback of industrial accidents and nuclear safety is explored: if the rigorous and well-documented methods of experience feedback in the nuclear field certainly set an example for other activities, nuclear safety can also benefit from inputs coming from the vast diversity of accidents arisen into industrial facilities because of common grounds. Among these common grounds we can find: -) the fuel cycle facilities use many chemicals and chemical processes that are also used by chemical industries; -) the problems resulting from the ageing of equipment affect both heavy and nuclear industries; -) the risk of hydrogen explosion; -) the risk of ammonia, ammonia is a gas used by nuclear power plants as an ingredient in the onsite production of mono-chloramine and ammonia is involved in numerous accidents in the industry: at least 900 entries can be found in the ARIA database. The paper is followed by the slides of the presentation

ACCIDENT WITH NEEDLESTICK: KNOWLEDGE AND USE OF SAFETY DEVICE

Directory of Open Access Journals (Sweden)

Sandra Maria Souza da Silva

2016-07-01

Full Text Available Health workers engaged in labour activities in environments surrounded the occupational hazards. Identify knowledge and use of safety devide for preventing accidents with sharp objects between nurses and nurse technicians, workers of the Intensive Care Unit, Emergency and Surgical Block, during the month of may 2015. Exploratory study, quantitative, developed in a teaching hospital in in Recife-PE. The data collection was conducted using a questionnaire prepared by the research authors. The results were submitted to descriptive statistical analysis, being evidenced that, although data indicate high rate of respondents know and use products with referencing safety devices to prevent accidents, cite gloves and masks as representatives of those materials, which requires clarification in discussion of the study. It is necessary to guide and clarify as to such mechanisms, through the permanent education, and training among workers.

Radiological protection, safety and security issues in the industrial and medical applications of radiation sources

Science.gov (United States)

Vaz, Pedro

2015-11-01

The use of radiation sources, namely radioactive sealed or unsealed sources and particle accelerators and beams is ubiquitous in the industrial and medical applications of ionizing radiation. Besides radiological protection of the workers, members of the public and patients in routine situations, the use of radiation sources involves several aspects associated to the mitigation of radiological or nuclear accidents and associated emergency situations. On the other hand, during the last decade security issues became burning issues due to the potential malevolent uses of radioactive sources for the perpetration of terrorist acts using RDD (Radiological Dispersal Devices), RED (Radiation Exposure Devices) or IND (Improvised Nuclear Devices). A stringent set of international legally and non-legally binding instruments, regulations, conventions and treaties regulate nowadays the use of radioactive sources. In this paper, a review of the radiological protection issues associated to the use of radiation sources in the industrial and medical applications of ionizing radiation is performed. The associated radiation safety issues and the prevention and mitigation of incidents and accidents are discussed. A comprehensive discussion of the security issues associated to the global use of radiation sources for the aforementioned applications and the inherent radiation detection requirements will be presented. Scientific, technical, legal, ethical, socio-economic issues are put forward and discussed.

Considering lessons learned about safety culture and their reflection to activity. After Fukushima Daiichi Nuclear Power Plant accident experience

International Nuclear Information System (INIS)

Obu, Etsuji; Hamada, Jun; Fukano, Takuya

2011-01-01

Fukushima Daiichi Nuclear Power Plant accident forced neighboring residents to evacuate for a long time and gave Public anxieties greatly and significant effects to social activities in Japan. Public trust of nuclear power was lost by not preventing the accident and future of nuclear power became reconsidered, which nuclear industry people regretted deeply. Japan Nuclear Technology Institute (JANTI) had conducted activities enhancing safety culture in nuclear industry. It would be necessary to consider improvements of accident prevention and mitigation measures after evaluating the accident in a viewpoint of 'safety culture'. Based on published information and knowledge accumulated by activities of JANTI, the accident was examined taking account of greatness of nuclear accident and its effects from the side of safety culture. Lessons learned about safety culture were pointed out as; (1) reconfirmation of specialty of nuclear technology. (2) reinforcement of questioning and learning attitudes and (3) improvement of evaluation capability of nuclear safety and safety assurance against external event. These were reflected in activities such as; (1) reconsideration of safety culture assessment, (2) strengthening further support to improve safety culture consciousness and (3) improvement of peer review activity. (T. Tanaka)

Overview of safety and environmental issues for inertial fusion energy

International Nuclear Information System (INIS)

Piet, S.J.; Brereton, S.J.; Tanaka, S.

1996-01-01

This paper summarizes safety and environmental issues of Inertial Fusion Energy (IFE): inventories, effluents, maintenance, accident safety, waste management, and recycling. The fusion confinement approach among inertial and magnetic options affects how the fusion reaction is maintained and which materials surround the reaction chamber. The target fill technology has a major impact on the target factory tritium inventory. IFE fusion reaction chambers usually employ some means to protect the first structural wall from fusion pulses. This protective fluid or granular bed also moderates and absorbs most neutrons before they reach the first structural wall. Although the protective fluid activates, most candidate fluids have low activation hazard. Hands-on maintenance seems practical for the driver, target factory, and secondary coolant systems; remote maintenance is likely required for the reaction chamber, primary coolant, and vacuum exhaust cleanup systems. The driver and fuel target facility are well separated from the main reaction chamber

Introduction of the Amendment of IAEA Safety Requirements Reflected Lessons Learned from Fukushima Nuclear Accident

Energy Technology Data Exchange (ETDEWEB)

Ahn, Sang-Kyu; Ahn, Hyung-Joon; Kim, Sun-Hae; Cheong, Jae-Hak [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2015-10-15

The following five Safety Requirements publications were amended: Governmental, Legal and Regulatory Framework for Safety (GSR Part 1, 2010), Site Evaluation for Nuclear Installations (NS-R-3, 2003), Safety of Nuclear Power Plants: Design (SSR-2/1, 2012), Safety of Nuclear Power Plants: Commissioning and Operation (SSR-2/2, 2011), and Safety Assessment for Facilities and Activities (GSR Part 4, 2009). Figure 1 shows IAEA Safety Standards Categories Major amendments of five Safety Requirements publications were introduced and analyzed in this study. The five IAEA safety requirements publications which are GSR Part 1 and 4, NS-R-3 and SSR-2/1 and 2, were amended to reflect the lesson learned from the Fukushima accident and other operating experiences. Specially, 36 provisions were modified and the new 29 provision with 1 requirement (No. 67: Emergency response facilities on the site) of the SSR-2/1 were established. Since the Fukushima accident happened, a new word, design extension conditions (DECs) which cover substantially the beyond design basis accidents (BDBA), including severe accident conditions, was created and more elaborated by the world nuclear experts. Design extension conditions could include conditions in events without significant fuel degradation and conditions with core melting. Figure 2 shows the range of the DECs. The amendment of the five IAEA safety requirements publications are focused at the prevention of initiating events, which would lead to the DECs, and mitigation of the consequences of DECs by the enhanced defense in depth principle. The following examples of the IAEA requirements to prevent the initiating events are: margins for withstanding external events; margins for avoiding cliff edge effects; safety assessment for multiple facilities or activities at a single site; safety assessment in cases where resources at a facility are shared; consideration of the potential occurrence of events in combination; establishing levels of hazard

Identification of new unresolved safety issues relating to nuclear power plants - special report to Congress. Congressional report

International Nuclear Information System (INIS)

1981-03-01

As a result of NRC staff review and extended collegial consultations and investigations within the NRC, the Commission has designated four new Unresolved Safety Issues (USIs). This report describes the process used to evaluate the large number of concerns and recommendations which resulted from the major investigations of the Three Mile Island-2 accident as well as other events and investigations of the past year, and the report identifies the four new USIs selected as follows: (1) Shutdown decay heat removal requirements (Task A-45); (2) Seismic qualification of equipment in operating plants (Task A-46); (3) Safety implications of control systems (Task A-47); and (4) Hydrogen control measures and effects of hydrogen burns on safety equipment (Task A-48). Appendix A of the report presents an expanded discussion of each new USI including issue definition, a preliminary discussion of the action plan and a basis for continued plant operations and licensing. Appendix B of the report provides a brief discussion of each of the candidate safety issues not designated as an USI

Thermal reactor safety

International Nuclear Information System (INIS)

1980-06-01

Information is presented concerning new trends in licensing; seismic considerations and system structural behavior; TMI-2 risk assessment and thermal hydraulics; statistical assessment of potential accidents and verification of computational methods; issues with respect to improved safety; human factors in nuclear power plant operation; diagnostics and activities in support of recovery; LOCA transient analysis; unresolved safety issues and other safety considerations; and fission product transport

Thermal reactor safety

Energy Technology Data Exchange (ETDEWEB)

1980-06-01

Information is presented concerning new trends in licensing; seismic considerations and system structural behavior; TMI-2 risk assessment and thermal hydraulics; statistical assessment of potential accidents and verification of computational methods; issues with respect to improved safety; human factors in nuclear power plant operation; diagnostics and activities in support of recovery; LOCA transient analysis; unresolved safety issues and other safety considerations; and fission product transport.

Advanced fuels safety comparisons

International Nuclear Information System (INIS)

Grolmes, M.A.

1977-01-01

The safety considerations of advanced fuels are described relative to the present understanding of the safety of oxide fueled Liquid Metal Fast Breeder Reactors (LMFBR). Safety considerations important for the successful implementation of advanced fueled reactors must early on focus on the accident energetics issues of fuel coolant interactions and recriticality associated with core disruptive accidents. It is in these areas where the thermal physical property differences of the advanced fuel have the greatest significance

Criticality accident of nuclear fuel facility. Think back on JCO criticality accident

International Nuclear Information System (INIS)

Naito, Keiji

2003-09-01

This book is written in order to understand the fundamental knowledge of criticality safety or criticality accident of nuclear fuel facility by the citizens. It consists of four chapters such as critical conditions and criticality accident of nuclear facility, risk of criticality accident, prevention of criticality accident and a measure at an occurrence of criticality accident. A definition of criticality, control of critical conditions, an aspect of accident, a rate of incident, damage, three sufferers, safety control method of criticality, engineering and administrative control, safety design of criticality, investigation of failure of safety control of JCO criticality accident, safety culture are explained. JCO criticality accident was caused with intention of disregarding regulation. It is important that we recognize the correct risk of criticality accident of nuclear fuel facility and prevent disasters. On the basis of them, we should establish safety culture. (S.Y.)

Accident Journalism and Traffic Safety Education: A Three-Phase Investigation of Accident Reporting in the Canadian Daily Press.

Science.gov (United States)

Wilde, Gerald J. S.; Ackersviller, Melody J.

A study examined the potential for development of a traffic accident-reporting form in the Canadian daily press that strengthens concern for road safety in the general population and enhances knowledge, attitudes, and behavior leading to greater safety. The investigation was conducted on three levels: a content analysis, a readership analysis, and…

Industrial Safety and Accidents Prevention

International Nuclear Information System (INIS)

Sajjad Akbar

2006-01-01

Accident Hazards, dangers, losses and risk are what we would to like to eliminate, minimize or avoid in industry. Modern industries have created many opportunities for these against which man's primitive instincts offer no protection. In today's complex industrial environment safety has become major preoccupation, especially after the realization that there is a clear economic incentive to do so. Industrial hazards may cause by human error or by physical or mechanical malfunction, it is very often possible to eliminate the worst consequences of human error by engineering modification. But the modification also needs checking very thoroughly to ensue that it has not introduced some new and unsuspected hazard. (author)

Thermal hydraulic features of the TMI accident

International Nuclear Information System (INIS)

Tolman, B.

1985-01-01

The TMI-2 accident resulted in extensive core damage and recent data confirms that the reactor vessel was challenged from molten core materials. A hypothesized TMI accident sencario is presented that consistently explains the TMI data and is also consistent with research findings from independent severe fuel damage experiements. The TMI data will prove useful in confirming our understanding of severe core damage accidents under realistic reactor systems conditions. This understanding will aid in addressing safety and regulatory issues related to severe core damage accidents in light water reactors

Evaluation of special safety features of the SNR-300 in view of the Chernobyl accident

International Nuclear Information System (INIS)

Vossebrecker, H.

1987-03-01

A comparison of those characteristics, which decisively influenced the accident in the RMBK-1000 reactor, with the safety features of SNR-300 has been performed. The conclusions of this comparison are presented in the present report. The SNR-300 is characterized by a stable reactivity behaviour and good controllability, whereas RBMK-1000 has an instable behaviour and complex spatial dependencies in the core. Among other points, design deficiencies in the protection and emergency shutdown systems were responsible for the Chernobyl accident. The protection and scram systems of the SNR-300 are unquestionably superior to those of the RBMK-1000 with regard to redundancy, diversity, degree of automation, separation of operational and safety-relevant tasks, protection against inadmissible interventions, effectiveness and safety reserves. Therefore, excursion accidents can be classified as hypothetical for SNR-300. Due to elementary physical properties, possible energy releases during hypothetical excursions are substantially lower for SNR-300 and would be controlled by the design of the primary system and containment systems. No damage limiting measures are provided in the RBMK-100 for excursion accidents. Finally, exothermal processes augmented the consequences of the accident in the RBMK-1000 and the long-lasting graphite fire intensified the release of radioactivity. In the SNR-300, however, inertisation of the containment, the steel plate lining and the floor troughs ensure that activity enclosure inside the containment after leakage or hypothetical excursion accident is not endangered by exothermal reactions. Further safety aspects are presented in the report, which can be linked with the accident in Chernobyl. In summary, it is obvious that the disadvantageous physical and technical features of the RBMK-1000 do either not exist in the SNR-300 or are covered by the safety design

Accidents in Malaysian construction industry: statistical data and court cases.

Science.gov (United States)

Chong, Heap Yih; Low, Thuan Siang

2014-01-01

Safety and health issues remain critical to the construction industry due to its working environment and the complexity of working practises. This research attempts to adopt 2 research approaches using statistical data and court cases to address and identify the causes and behavior underlying construction safety and health issues in Malaysia. Factual data on the period of 2000-2009 were retrieved to identify the causes and agents that contributed to health issues. Moreover, court cases were tabulated and analyzed to identify legal patterns of parties involved in construction site accidents. Approaches of this research produced consistent results and highlighted a significant reduction in the rate of accidents per construction project in Malaysia.

Safety challenges after the Fukushima accident for operated installations others than EDF reactors

International Nuclear Information System (INIS)

Sene, Monique; Rollinger, Francois; Lheureux, Yves; Lizot, Marie-Therese; Kerdelhue, M.; Py, M.E.; Leroyer, Veronique; Pultier, Marc; Kassiotis, Christophe; Chambrette, Pierre; Devaux, Pascal; Baron, Yves; Collinet, Jacques

2013-12-01

This document contains Power Point presentations which, within the perspective created by the Fukushima accident, address various aspects of safety issues for installations other than currently operated EDF reactors. These contributions propose: an agenda of additional safety assessments (ECS) performed on these installations and an examination of responses made to prescriptions made on the 16 June 2012; a presentation by the IRSN of ECS performed in Areva plants; a presentation by Areva of arrangements related to these ECS; a presentation of the Manche local information commissions (CLI) and a presentation of their approach according to a white paper for the safety of civil nuclear installations located in the Manche department; a presentation by the IRSN on ECS concerning various basic nuclear installations such as laboratories, experimental reactors and stopped reactors; a presentation by the CEA of ECS of its installations (context, approach, execution and conclusions); a presentation by the ANCCLI about ASN decision and decision projects about the hard core according to ECS (example of the High flux reactor in the ILL in Grenoble)

An application of probabilistic safety assessment methods to model aircraft systems and accidents

Energy Technology Data Exchange (ETDEWEB)

Martinez-Guridi, G.; Hall, R.E.; Fullwood, R.R.

1998-08-01

A case study modeling the thrust reverser system (TRS) in the context of the fatal accident of a Boeing 767 is presented to illustrate the application of Probabilistic Safety Assessment methods. A simplified risk model consisting of an event tree with supporting fault trees was developed to represent the progression of the accident, taking into account the interaction between the TRS and the operating crew during the accident, and the findings of the accident investigation. A feasible sequence of events leading to the fatal accident was identified. Several insights about the TRS and the accident were obtained by applying PSA methods. Changes proposed for the TRS also are discussed.

Nuclear technology and reactor safety engineering. The situation ten years after the Chernobyl reactor accident

International Nuclear Information System (INIS)

Birkhofer, A.

1996-01-01

Ten years ago, on April 26, 1986 the most serious accident ever in the history of nuclear tgechnology worldwide happened in unit 4 of the nuclear power plant in Chernobyl in the Ukraine, this accident unveiling to the world at large that the Soviet reactor design lines are bearing unthought of safety engineering deficits. The dimensions of this reactor accident on site, and the radioactive fallout spreading far and wide to many countries in Europe, vividly nourished the concern of great parts of the population in the Western world about the safety of nuclear technology, and re-instigated debates about the risks involved and their justification. Now that ten years have elapsed since the accident, it is appropriate to strike a balance and analyse the situation today. The number of nuclear power plants operating worldwide has been growing in the last few years and this trend will continue, primarily due to developments in Asia. The Chernobyl reactor accident has pushed the international dimension of reactor safety to the foreground. Thus the Western world had reason enough to commit itself to enhancing the engineered safety of reactors in East Europe. The article analyses some of the major developments and activities to date and shows future perspectives. (orig.) [de

Analysis and discussion on reports of additional safety assessment of nuclear installations with respect to the Fukushima accident

International Nuclear Information System (INIS)

Sene, Monique; Sene, Raymond

2011-11-01

This document proposes an analysis of the reports made by the different operators of nuclear installations within the frame of a safety audit of the French nuclear installations with respect to the Fukushima accident. Operators (mainly AREVA, the CEA and EDF) were asked to perform additional safety assessments. In a first part, the conclusions of EDF reports are analysed regarding the seismic risk, the flooding risk, the situation of some specific sites (Fessenheim, Tricastin), other phenomena (rains, winds), loss of electricity supplies and of cooling systems, severe accidents, hydrogen issue, chemical hazards, subcontractors, crisis management. Conclusions of AREVA reports are analysed for the different sites (Tricastin, La Hague, MELOX factory, Romans factory). Conclusions of CEA reports are analysed for the different concerned installations (ATPu, Masurca, Osiris, Phenix, Jules Horowitz reactor). A second part proposes a global analysis of EDF's additional safety assessment reports regarding earthquake, flooding, other extreme natural phenomena, loss of electricity supplies and cooling system, subcontracting conditions, crisis management, and radiation protection organisation. AREVA's and CEA's reports are then analysed in terms of report structure and content, and for the different concerned sites

77 FR 45417 - Pipeline Safety: Inspection and Protection of Pipeline Facilities After Railway Accidents

Science.gov (United States)

2012-07-31

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket No... Accidents AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA); DOT. [[Page 45418

Safety in Academic Chemistry Laboratories: Volume 2. Accident Prevention for Faculty and Administrators, 7th Edition.

Science.gov (United States)

American Chemical Society, Washington, DC.

This book contains volume 2 of 2 and describes safety guidelines for academic chemistry laboratories to prevent accidents for college and university students. Contents include: (1) "Organizing for Accident Prevention"; (2) "Personal Protective Equipment"; (3) "Labeling"; (4) "Material Safety Data Sheets (MSDSs)"; (5) "Preparing for Medical…

Technique of research of severe accidents and substantiation of safety of nuclear systems

International Nuclear Information System (INIS)

Ivanov, E.A.; Tchenov, S.V.

2001-01-01

Work is devoted to development of possible ways of solution of the problems of nuclear safety substantiation. We believe that safety in severe accidents is one of significant factors, which restrict value of nuclear industry in future power production. In connection with it we can conclude followed items: -) Substantiation of safety in severe accidents in nuclear system should be built on a deterministic way of guaranteed exception of heavy consequences; -) It is easy that this aim can be achieved by modeling in functions of common type; -) Main purpose of this work is to show that it is possible to estimate physical allowed state of system in emergency and find of trajectory of heaviest scenarios by optimization procedure; and -) In this work we have developed new method and computer code purposed for study of accident conditions of water cooled un-managed nuclear systems such as cooling ponds of spent fuel, experimental facilities etc. (authors)

Road safety in a globalised and more sustainable world: current issues and future challenges.

Science.gov (United States)

Daniels, Stijn; Risser, Ralf

2014-01-01

Although many countries have had considerable success in reducing traffic injuries over recent decades, there are still some fundamental problems in this area. At the same time, there is increasing focus on road safety research and policy development in the context of globalisation, sustainability, liveability and health. This special section presents a selection of papers that were presented at the annual ICTCT workshop held on the 8th and 9th of November 2012 in Hasselt, Belgium, and accepted for publication in Accident Analysis and Prevention following the journal's reviewing procedure. The aim of the ICTCT workshop was to analyse road safety facts, data and visions for the future in the wider context of current issues and future challenges in road safety. Copyright © 2013 Elsevier Ltd. All rights reserved.

Generalization of Nuclear Safety and Course of Accident Events Research in the Ignalina NPP

International Nuclear Information System (INIS)

Kaliatka, A.; Uspuras, E.

2001-01-01

The safety analysis shown that after implementation of SAR recommendations Ignalina NPP is adequately protected against accidents which required fast initiation of automatic protections. In case of accidents with long-term loss of core cooling additional operator actions are required. Accident management in case long-term core cooling are analyzed in this paper. (author)

International Workshop on Post-Accident Food Safety Science, Hosted by the Cabinet Office, Government of Japan

International Nuclear Information System (INIS)

Tsukada, Hirofumi; Oikawa, Shinji; Aoki, Jin; Fujii, Masahiro; Okabe, Yoko; Koyama, Ryota; Iracane, Daniel; Lazo, Ted; ); Theelen, Rob; Sekiya, Naoya; Ito, Toshihiko; Kazumata, Seiichi; Hatta, Nobuyuki; Yuasa, Osamu; Nonaka, Shunkichi; Sato, Chie; Nisbet, Anne; Kai, Michiaki; Gusev, Igor; ); Nosske, Dietmar; Vandenhove, Hildegarde; Leonard, Kinson; Perks, Christopher; Liland, Astrid; Mostovenko, Andrei; Arai, Yoshimitsu; Sato, Mamoru; Kokubun, Youichi; Nemoto, Yoshiharu; Boyd, Mike; Homma, Toshimitsu; ); Lecomte, Jean Francois; Perks, Christopher

2016-11-01

monitoring/inspection has also been conducted for enormous samples every year. These measures have been combined to allow distribution of safe Japanese food. Many national governments and international organisations have focused on these issues since the accident. This workshop discusses the science supporting food safety standards, the science of managing contamination levels in food products to meet food safety standards, and the local, national and international organisational aspects to take into consideration to ensure food safety. This document is the compilation of the presentations (slides) given at the workshop in both English and Japanese languages

Severe accident assessment. Results of the reactor safety research project VAHTI

International Nuclear Information System (INIS)

Sairanen, R.

1997-10-01

The report provides a summary of the publicly funded nuclear reactor safety research project Severe Accident Management (VAHTI). The project has been conducted at the Technical Research Centre of Finland (VTT) during the years 1994-96. The main objective was to assist the severe accident management programmes of the Finnish nuclear power plants. The project was divided into five work packages: (1) thermal hydraulic validation of the APROS code, (2) core melt progression within a BWR pressure vessel, (3) failure mode of the BWR pressure vessel, (4) Aerosol behaviour experiments, and (5) development of a computerized severe accident training tool

Operational safety of nuclear power plants

International Nuclear Information System (INIS)

Tanguy, P.

1987-01-01

The operational safety of nuclear power plants has become an important safety issue since the Chernobyl accident. A description is given of the various aspects of operational safety, including the importance of human factors, responsibility, the role and training of the operator, the operator-machine interface, commissioning and operating procedures, experience feedback, and maintenance. The lessons to be learnt from Chernobyl are considered with respect to operator errors and the management of severe accidents. Training of personnel, operating experience feedback, actions to be taken in case of severe accidents, and international cooperation in the field of operational safety, are also discussed. (U.K.)

Design Safety Considerations for Water Cooled Small Modular Reactors Incorporating Lessons Learned from the Fukushima Daiichi Accident

International Nuclear Information System (INIS)

2016-03-01

The global future deployment of advanced nuclear reactors for electricity generation depends primarily on the ability of nuclear industries, utilities and regulatory authorities to further enhance their reliability and economic competitiveness while satisfying stringent safety requirements. The IAEA has a project to help coordinate Member States efforts in the development and deployment of small and medium sized or small modular reactor (SMR) technology. This project aims simultaneously to facilitate SMR technology developers and potential SMR uses, particularly States embarking on a nuclear power programme, in identifying key enabling technologies and enhancing capacity building by resolving issues relevant to deployment, including nuclear reactor safety. The objective of this publication is to explore common practices for Member States, which will be an essential resource for future development and deployment of SMR technology. The accident at the Fukushima Daiichi nuclear power plant was caused by an unprecedented combination of natural events: a strong earthquake, beyond the design basis, followed by a series of tsunamis of heights exceeding the design basis tsunami considered in the flood analysis for the site. Consequently, all the operating nuclear power plants and advanced reactors under development, including SMRs, have been incorporating lessons learned from the accident to assure and enhance the performance of the engineered safety features in coping with such external events

LMFBR safety. 3. Review of current issues and bibliography of literature (1972--1974)

International Nuclear Information System (INIS)

Buchanan, J.R.; Keilholtz, G.W.

1977-01-01

The report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1972 through 1974. The bibliography consists of approximately 1380 abstracts covering research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included

LMFBR safety. 3. Review of current issues and bibliography of literature (1972--1974)

Energy Technology Data Exchange (ETDEWEB)

Buchanan, J.R.; Keilholtz, G.W.

1977-02-24

The report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1972 through 1974. The bibliography consists of approximately 1380 abstracts covering research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included.

LMFBR safety. 1. Review of current issues and bibliography of literature, 1960--1969

Energy Technology Data Exchange (ETDEWEB)

Buchanan, J.R.; Keilholtz, G.W.

1976-08-16

This report discusses the current status of liquid-metal fast breeder (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1960 through 1969. The bibliography consists of 1560 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness.

LMFBR safety. 1. Review of current issues and bibliography of literature, 1960--1969

International Nuclear Information System (INIS)

Buchanan, J.R.; Keilholtz, G.W.

1976-01-01

This report discusses the current status of liquid-metal fast breeder (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1960 through 1969. The bibliography consists of 1560 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness

To improve nuclear plant safety by learning from accident's experience

International Nuclear Information System (INIS)

Matsumoto, Hidezo; Kida, Masanori; Kato, Hiroyuki; Hara, Shin-ichi

1994-01-01

The ultimate goal of this study is to produce an expert system that enables the experience (records and information) gained from accidents to be put to use towards improving nuclear plant safety. A number of examples have been investigated, both domestic and overseas, in which experience gained from accidents was utilized by utilities in managing and operating their nuclear power stations to improve safety. The result of investigation has been used to create a general 'basic flow' to make the best use of experience. The ultimate goal is achieved by carrying out this 'basic flow' with artificial intelligence (AI). To do this, it is necessary (1) to apply language analysis to process the source information (primary data base; domestic and overseas accident's reports) into the secondary data base, and (2) to establish an expert system for selecting (screening) significant events from the secondary data base. In the processing described in item (1), a multi-lingual thesaurus for nuclear-related terms become necessary because the source information (primary data bases) itself is multi-lingual. In the work described in item (2), the utilization of probabilistic safety assessment (PSA), for example, is a candidate method for judging the significance of events. Achieving the goal thus requires developing various new techniques. As the first step of the above long-term study project, this report proposes the 'basic flow' and presents the concept of how the nuclear-related AI can be used to carry out this 'basic flow'. (author)

Additional safety assessments. Report by the Nuclear Safety Authority - December 2011

International Nuclear Information System (INIS)

2011-12-01

The first part of this voluminous report proposes an assessment of targeted audits performed in French nuclear installations (water pressurized reactors on the one hand, laboratories, factories and waste and dismantling installations on the other hand) on issues related to the Fukushima accident. The examined issues were the protection against flooding and against earthquake, and the loss of electricity supplies and of cooling sources. The second part addresses the additional safety assessments of the reactors and the European resistance tests: presentation of the French electronuclear stock, earthquake, flooding and natural hazards (installation sizing, safety margin assessment), loss of electricity supplies and cooling systems, management of severe accidents, subcontracting conditions. The third part addresses the same issues for nuclear installations other than nuclear power reactors

Basic safety principles: Lessons learned

International Nuclear Information System (INIS)

Erp, J.B. van

1997-01-01

The presentation reviews the following issues: basic safety principles and lessons learned; some conclusions from the Kemeny report on the accident at TMI; some recommendations from the Kemeny report on the accident at TMI; conclusions and recommendations from the Rogovin report on the accident on TMI; instrumentation deficiencies (from Rogovin report)

Basic safety principles: Lessons learned

Energy Technology Data Exchange (ETDEWEB)

Erp, J.B. van [Argonne National Lab., IL (United States)

1997-09-01

The presentation reviews the following issues: basic safety principles and lessons learned; some conclusions from the Kemeny report on the accident at TMI; some recommendations from the Kemeny report on the accident at TMI; conclusions and recommendations from the Rogovin report on the accident on TMI; instrumentation deficiencies (from Rogovin report).

Analysis of occupational accidents: prevention through the use of additional technical safety measures for machinery.

Science.gov (United States)

Dźwiarek, Marek; Latała, Agata

2016-01-01

This article presents an analysis of results of 1035 serious and 341 minor accidents recorded by Poland's National Labour Inspectorate (PIP) in 2005-2011, in view of their prevention by means of additional safety measures applied by machinery users. Since the analysis aimed at formulating principles for the application of technical safety measures, the analysed accidents should bear additional attributes: the type of machine operation, technical safety measures and the type of events causing injuries. The analysis proved that the executed tasks and injury-causing events were closely connected and there was a relation between casualty events and technical safety measures. In the case of tasks consisting of manual feeding and collecting materials, the injuries usually occur because of the rotating motion of tools or crushing due to a closing motion. Numerous accidents also happened in the course of supporting actions, like removing pollutants, correcting material position, cleaning, etc.

The R and D issues necessary to achieve the safety design of commercialized liquid-metal cooled fast reactors

International Nuclear Information System (INIS)

Shoji, Kotake; Koji, Dozaki; Shigenobu, Kubo; Yoshio, Shimakawa; Hajime, Niwa; Masakazu, Ichimiya

2002-01-01

Within the framework of the feasibility study on commercialized fast reactor cycle systems (hereafter described as F/S), the safety design principle is investigated and several kinds of design studies are now in progress. Among the designs for liquid-metal cooled fast reactor (LMR), the advanced loop type sodium cooled fast reactor (FR) is one of the promising candidate as future commercialized LMR. In this paper, the safety related research and development (R and D) issues necessary to achieve the safety design are described along the defence-in-depth principle, taking account of not only the system characteristics of the advanced loop concepts but also design studies and R and D experiences so far. Safety issues related to the hypothetical core disruptive accidents (CDA) are emphasized both from the prevention and mitigation. A re-criticality free core concept with a special fuel assembly is pursued by performing both analytical and experimental efforts, in order to realize the rational design and to establish easy-to-understand safety logic. Sodium related issues are also given to ensure plant availability and to enhance the acceptability to the public. (authors)

Safety Enhancements for PHWRs Based on Macroscopic Losses of the Fukushima Accident

Directory of Open Access Journals (Sweden)

Sang Ho Kim

2015-01-01

Full Text Available The role of nuclear energy is to supply electric power on a stable basis to meet increasing demands, reduce carbon dioxide emissions, and maintain stable electric power costs while ensuring safety. The Fukushima accident taught us many lessons for creating safer nuclear power plants. Considering the design of systems, the areas of weakness at the Fukushima nuclear power plants can be divided into three categories: plant protection, electricity supply, and cooling of the nuclear fuel. In this paper, focusing on these three areas, the lessons learned are proposed and applied for pressurized heavy water reactors. Firstly, hard protection against external risks ensures the integrity of components and systems such that they can perform their original functions. Secondly, additional emergency power supply systems for electrical redundancy and diversity can improve the response capabilities for an accident by increasing the availability of active components. Thirdly, cooling for removing decay heat can be augmented by adopting diverse safety systems derived from other types of reactors. This study is expected to contribute to the safety enhancement of pressurized heavy water reactors by applying design changes based on the lessons learned from the Fukushima accident.

Determination of Optimal Flow Paths for Safety Injection According to Accident Conditions

Energy Technology Data Exchange (ETDEWEB)

Yoo, Kwae Hwan; Kim, Ju Hyun; Kim, Dong Yeong; Na, Man Gyun [Chosun Univ., Gwangju (Korea, Republic of); Hur, Seop; Kim, Changhwoi [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

In case severe accidents happen, major safety parameters of nuclear reactors are rapidly changed. Therefore, operators are unable to respond appropriately. This situation causes the human error of operators that led to serious accidents at Chernobyl. In this study, we aimed to develop an algorithm that can be used to select the optimal flow path for cold shutdown in serious accidents, and to recover an NPP quickly and efficiently from the severe accidents. In order to select the optimal flow path, we applied a Dijkstra algorithm. The Dijkstra algorithm is used to find the path of minimum total length between two given nodes and needs a weight (or length) matrix. In this study, the weight between nodes was calculated from frictional and minor losses inside pipes. That is, the optimal flow path is found so that the pressure drop between a starting node (water source) and a destination node (position that cooling water is injected) is minimized. In case a severe accident has happened, if we inject cooling water through the optimized flow path, then the nuclear reactor will be safely and effectively returned into the cold shutdown state. In this study, we have analyzed the optimal flow paths for safety injection as a preliminary study for developing an accident recovery system. After analyzing the optimal flow path using the Dijkstra algorithm, and the optimal flow paths were selected by calculating the head loss according to path conditions.

Industrial Accidents Triggered by Natural Hazards: an Emerging Risk Issue

Science.gov (United States)

Renni, Elisabetta; Krausmann, Elisabeth; Basco, Anna; Salzano, Ernesto; Cozzani, Valerio

2010-05-01

Natural disasters such as earthquakes, tsunamis, flooding or hurricanes have recently and dramatically hit several countries worldwide. Both direct and indirect consequences involved the population, causing on the one hand a high number of fatalities and on the other hand so relevant economical losses that the national gross product may be affected for many years. Loss of critical industrial infrastructures (electricity generation and distribution, gas pipelines, oil refineries, etc.) also occurred, causing further indirect damage to the population. In several cases, accident scenarios with large releases of hazardous materials were triggered by these natural events, causing so-called "Natech events", in which the overall damage resulted from the simultaneous consequences of the natural event and of the release of hazardous substances. Toxic releases, large fires and explosions, as well as possible long-term environmental pollution, economical losses, and overloading of emergency systems were recognised by post-event studies as the main issues of these Natech scenarios. In recent years the increasing frequency and severity of some natural hazards due to climate change has slowly increased the awareness of Natech risk as an emerging risk among the stakeholders. Indeed, the iNTeg-Risk project, co-funded by the European Commission within the 7th Framework Program specifically addresses these scenarios among new technological issues on public safety. The present study, in part carried out within the iNTeg-Risk project, was aimed at the analysis and further development of methods and tools for the assessment and mitigation of Natech accidents. Available tools and knowledge gaps in the assessment of Natech scenarios were highlighted. The analysis mainly addressed the potential impact of flood, lightning and earthquake events on industrial installations where hazardous substances are present. Preliminary screening methodologies and more detailed methods based on

Chernobyl accident consequences in Germany: Nuclear safety and radiation protection

International Nuclear Information System (INIS)

Edelhauser, H.; Wendling, R.D.; Weiss, W.; Klonk, H.; Weil, L.

1997-01-01

A working Programme of the Federal Government was initiated on 26 May 1986 to cover all aspects of nuclear safety and public health, including research and public affairs in the light of the European and international activities resulting from the accident

Proceedings of the Second NASA Aviation Safety Program Weather Accident Prevention Review

Science.gov (United States)

Martzaklis, K. Gus (Compiler)

2003-01-01

The Second NASA Aviation Safety Program (AvSP) Weather Accident Prevention (WxAP) Annual Project Review held June 5-7, 2001, in Cleveland, Ohio, presented the NASA technical plans and accomplishments to the aviation community. NASA-developed technologies presented included an Aviation Weather Information System with associated digital communications links, electronic atmospheric reporting technologies, forward-looking turbulence warning systems, and turbulence mitigation procedures. The meeting provided feedback and insight from the aviation community of diverse backgrounds and assisted NASA in steering its plans in the direction needed to meet the national safety goal of 80-percent reduction of aircraft accidents by 2007. The proceedings of the review are enclosed.

Revised Severe Accident Research Program plan, FY 1990--1992

International Nuclear Information System (INIS)

1989-08-01

For the past 10 years, since the Three Mile Island accident, the NRC has sponsored an active research program on light-water-reactor severe accidents as part of a multi-faceted approach to reactor safety. This report describes the revised Severe Accident Research Program (SARP) and how the revisions are designed to provide confirmatory information and technical support to the NRC staff in implementing the staff's Integration Plan for Closure of Severe Accident Issues as described in SECY-88-147. The revised SARP addresses both the near-term research directed at providing a technical basis upon which decisions on important containment performance issues can be made and the long-term research needed to confirm and refine our understanding of severe accidents. In developing this plan, the staff recognized that the overall goal is to reduce the uncertainties in the source term sufficiently to enable the staff to make regulatory decisions on severe accident issues. However, the staff also recognized that for some issues it may not be practical to attempt to further reduce uncertainties, and some regulatory decisions or conclusions will have to be made with full awareness of existing uncertainties. 2 figs., 1 tab

AN ANALYSIS OF ACCIDENT TRENDS AND MODELING OF SAFETY INDICES IN AN INDIAN CONSTRUCTION ORGANIZATION

Directory of Open Access Journals (Sweden)

Sunku Venkata Siva Rajaprasad

2016-09-01

Full Text Available Construction industry has been recognized as a hazardous industry in many countries due to distinct nature of execution of works.The accident rate in construction sector is high all over the world due to dynamic nature of work activities. Occurrence of accidents and its severity in construction industry is several times higher than the manufacturing industries. The study was limited to a major construction organization in India to examine the trends in construction accidents for the period 2008-2014. In India, safety performance is gauged basing on safety indices; frequency, severity and incidence rates. It is not practicable to take decisions or to implement safety strategies on the basis of indices. The data used for this study was collected from a leading construction organization involved in execution of major construction activities all over India and abroad. The multiple regression method was adopted to model the pattern of safety indices wise .The pattern showed that significant relationships exist between the three safety indices and the related independent variables.

Safety improvements at Canadian nuclear power plants in the aftermath of Fukushima accident

International Nuclear Information System (INIS)

Rzentkowski, G.; Khouaja, H.

2014-01-01

This paper describes the safety review of operating nuclear power plants undertaken by the Canadian Nuclear Safety Commission in light of the March 11, 2011 accident at the Fukushima Daiichi Nuclear Power Plants (NPPs). The review confirmed that the Canadian NPPs are robust and have a strong design relying on multiple layers of defence to protect the public from credible external events. Nevertheless, in the spirit of continuous safety improvements, the review identified a number of recommendations to further strengthen reactor defence-in-depth in preventing and mitigating the consequences of beyond design basis accidents, enhance onsite and offsite emergency response, and improve the CNSC regulatory framework. Progress achieved to date, in implementing these measures, is described in this paper along with a summary of safety benefits for each level of the reactor defence-in-depth. (author)

Safety improvements at Canadian nuclear power plants in the aftermath of Fukushima accident

Energy Technology Data Exchange (ETDEWEB)

Rzentkowski, G.; Khouaja, H. [Canadian Nuclear Safety Commission, Ottawa, ON (Canada)

2014-07-01

This paper describes the safety review of operating nuclear power plants undertaken by the Canadian Nuclear Safety Commission in light of the March 11, 2011 accident at the Fukushima Daiichi Nuclear Power Plants (NPPs). The review confirmed that the Canadian NPPs are robust and have a strong design relying on multiple layers of defence to protect the public from credible external events. Nevertheless, in the spirit of continuous safety improvements, the review identified a number of recommendations to further strengthen reactor defence-in-depth in preventing and mitigating the consequences of beyond design basis accidents, enhance onsite and offsite emergency response, and improve the CNSC regulatory framework. Progress achieved to date, in implementing these measures, is described in this paper along with a summary of safety benefits for each level of the reactor defence-in-depth. (author)

Analysis of occupational accidents: prevention through the use of additional technical safety measures for machinery

Science.gov (United States)

Dźwiarek, Marek; Latała, Agata

2016-01-01

This article presents an analysis of results of 1035 serious and 341 minor accidents recorded by Poland's National Labour Inspectorate (PIP) in 2005–2011, in view of their prevention by means of additional safety measures applied by machinery users. Since the analysis aimed at formulating principles for the application of technical safety measures, the analysed accidents should bear additional attributes: the type of machine operation, technical safety measures and the type of events causing injuries. The analysis proved that the executed tasks and injury-causing events were closely connected and there was a relation between casualty events and technical safety measures. In the case of tasks consisting of manual feeding and collecting materials, the injuries usually occur because of the rotating motion of tools or crushing due to a closing motion. Numerous accidents also happened in the course of supporting actions, like removing pollutants, correcting material position, cleaning, etc. PMID:26652689

Safety in Academic Chemistry Laboratories: Volume 1. Accident Prevention for College and University Students, 7th Edition.

Science.gov (United States)

American Chemical Society, Washington, DC.

This book contains volume 1 of 2 and describes safety guidelines for academic chemistry laboratories to prevent accidents for college and university students. Contents include: (1) "Your Responsibility for Accident Prevention"; (2) "Guide to Chemical Hazards"; (3) "Recommended Laboratory Techniques"; and (4) "Safety Equipment and Emergency…

Safety demonstration analyses at JAERI for severe accident during overland transport of fresh nuclear fuel

International Nuclear Information System (INIS)

Nomura, Yasushi; Kitao, Kohichi; Karasawa, Kiyonori; Yamada, Kenji; Takahashi, Satoshi; Watanabe, Kohji; Okuno, Hiroshi; Miyoshi, Yoshinori

2005-01-01

It is expected in the near future that more and more fresh nuclear fuel will be transported in a variety of transport packages to cope with increasing demand from nuclear fuel cycle facilities. Accordingly, safety demonstration analyses are planned and conducted at JAERI under contract with the Ministry of Economy, Trade and Industry of Japan. These analyses are conducted in a four year plan from 2001 to 2004 to verify integrity of packaging against leakage of radioactive material in the case of a severe accident postulated to occur during transportation, for the purpose of gaining acceptance of such nuclear fuel activities. In order to create the accident scenarios, actual transportation routes were surveyed, accident or incident records were tracked, international radioactive material transport regulations such as IAEA rules were investigated and thus, accident conditions leading to mechanical damages and thermal failure were determined to characterize the scenarios. As a result, the worst-case conditions of run-off-the-road accidents were set up to define the impact against a concrete or asphalt surface. For fire accident scenarios to be set up, collisions were assumed to occur with an oil tanker carrying lots of inflammable material in open air, or with a commonly used two-ton-truck inside a tunnel without ventilation. Then the cask models were determined for these safety demonstration analyses to represent those commonly used for fresh nuclear fuel transported throughout Japan. Following the postulated accident scenarios, the mechanical damages were analyzed by using the general-purpose finite element code LS-DYNA with three-dimensional elements. It was found that leak tightness of the package be maintained even in the severe impact scenario. Then the thermal safety was analyzed by using the general-purpose finite element code ABAOUS with three-dimensional elements to describe cask geometry. As a result of the thermal analyses, the integrity of the containment

Maintenance as a safety issue.

Science.gov (United States)

White, Jim

2008-11-01

Because safety is related to electrical power systems maintenance, it seems reasonable to assume there could be legal issues if maintenance is not performed. OSHA has not yet taken the stand that not performing maintenance as required by the manufacturer, NFPA 70B, or ANSI/NETA MTS-07 constitutes a willful violation. OSHA defines a willful citation as one where: "the employer knowingly commits with plain indifference to the law. The employer either knows that what he or she is doing constitutes a violation, or is aware that a hazardous condition existed and made no reasonable effort to eliminate it". However, NFPA 70E 2009 requires this maintenance, and OSHA has stated on its Web site that NFPA 70E is "a guide for meeting the requirements of the OSHA electrical regulations". In addition, federal courts have found that NFPA 70E is "standard industry practice." Once a company receives and accepts a willful citation, especially if received as the result of an accident investigation, its worker's compensation protection no longer shields it. One definition given by a trial attorney for a willful citation was that it is equal to negligent behavior. Be smart: Maintain that equipment and save yourself major problems, including unscheduled shutdowns and possible litigation.

Radiation protection issues on preparedness and response for a severe nuclear accident: experiences of the Fukushima accident.

Science.gov (United States)

Homma, T; Takahara, S; Kimura, M; Kinase, S

2015-06-01

Radiation protection issues on preparedness and response for a severe nuclear accident are discussed in this paper based on the experiences following the accident at Fukushima Daiichi nuclear power plant. The criteria for use in nuclear emergencies in the Japanese emergency preparedness guide were based on the recommendations of International Commission of Radiological Protection (ICRP) Publications 60 and 63. Although the decision-making process for implementing protective actions relied heavily on computer-based predictive models prior to the accident, urgent protective actions, such as evacuation and sheltering, were implemented effectively based on the plant conditions. As there were no recommendations and criteria for long-term protective actions in the emergency preparedness guide, the recommendations of ICRP Publications 103, 109, and 111 were taken into consideration in determining the temporary relocation of inhabitants of heavily contaminated areas. These recommendations were very useful in deciding the emergency protective actions to take in the early stages of the Fukushima accident. However, some suggestions have been made for improving emergency preparedness and response in the early stages of a severe nuclear accident. © The Chartered Institution of Building Services Engineers 2014.

Safety and man in light of the analysis of major technical accidents

International Nuclear Information System (INIS)

Carnino, A.

1990-01-01

Up to the seventies, it was not easy to admit human failure as a cause of industrial accidents. Man was considered as reliable. With the perfection of materials, technical systems and industrial processes though, man has become the weakest link in the chain of technical events. He is and stays a remarkably reliable being, with a roughly estimated average failure quota of 1:1000 manipulations. If the hypothetical risk should be kept very low, this value can become a problem. Instead of judging a mistake as a punishable crime, as the present tendency will have it, a more differentiated, systematical approach is called for. By means of an analysis of four major accidents - Chernobyl, Three Mile Island, Challenger and Bhopal - interesting parallels between the causes of such accidents can be found. Human failure, e.g. of a surgeon, is in most cases, the direct cause of an accident. A whole series of further causes, which can be assigned to different areas of influence but are usually interdependent, also play a role. While the human factor must be viewed as more or less predetermined, far reaching improvements can be made to reduce the risk of accident. Today, thanks to modern technology and new findings, it is possible to practically neutralize human error. This creates more costs and necessitates giving up short term production maximization. It also requires the willingness to give safety absolute priority. The name 'culture de surete' (safety culture) is used to describe this concept. Surprising similarities between the causes of the four mentioned major accidents were discovered. Certain circumstances, such as the time of day, played a role. The concept of a plant, resp. technical process has an essential influence, as well as company policy (importance of safety, preparation of emergency procedures, training, maintenance, company rules) and management (evaluation and realization of foreign and the company's own operation experiences and error alarms). (author) 7

Improving Aviation Safety in Indonesia: How Many More Accidents?

Directory of Open Access Journals (Sweden)

Ridha Aditya Nugraha

2016-12-01

Full Text Available Numerous and consecutive aircraft accidents combined with a consistent failure to meet international safety standards in Indonesia, namely from the International Civil Aviation Organization and the European Aviation Safety Agency have proven a nightmare for the country’s aviation safety reputation. There is an urgent need for bureaucracy reform, harmonization of legislation, and especially ensuring legal enforcement, to bring Indonesian aviation safety back to world standards. The Indonesian Aviation Law of 2009 was enacted to reform the situation in Indonesia. The law has become the ground for drafting legal framework under decrees of the Minister of Transportation, which have allowed the government to perform follow-up actions such as establishing a single air navigation service provider and guaranteeing the independency of the Indonesian National Transportation Safety Committee. A comparison with Thailand is made to enrich the perspective. Finally, foreign aviation entities have a role to assist states, in this case Indonesia, in improving its aviation safety, considering the global nature of air travel.

Type A behavior pattern, accident optimism and fatalism: an investigation into non-compliance with safety work behaviors among hospital nurses.

Science.gov (United States)

Ugwu, Fabian O; Onyishi, Ike E; Ugwu, Chidi; Onyishi, Charity N

2015-01-01

Safety work behavior has continued to attract the interest of organizational researchers and practitioners especially in the health sector. The goal of the study was to investigate whether personality type A, accident optimism and fatalism could predict non-compliance with safety work behaviors among hospital nurses. One hundred and fifty-nine nursing staff sampled from three government-owned hospitals in a state in southeast Nigeria, participated in the study. Data were collected through Type A Behavior Scale (TABS), Accident Optimism, Fatalism and Compliance with Safety Behavior (CSB) Scales. Our results showed that personality type A, accident optimism and fatalism were all related to non-compliance with safety work behaviors. Personality type A individuals tend to comply less with safety work behaviors than personality type B individuals. In addition, optimistic and fatalistic views about accidents and existing safety rules also have implications for compliance with safety work behaviors.

Classification of the railway accident in accordance with the requirement of the safety analysis of transporting spent fuel

International Nuclear Information System (INIS)

Wu Tao

1993-01-01

Based on the analysis of the difference between the accident severity categorization used in the Ministry of Railway and that used in the safety analysis of the transporting spent fuel, a method used for the classification of the railway accident in accordance with the requirement of the safety analysis of transporting spent fuel is suggested. The method classifies the railway accidents into 10 scenarios and make it possible to scale the accident through directly using the data documented by the Ministry of Railway without any additional effort

Process hazards analysis (PrHA) program, bridging accident analyses and operational safety

International Nuclear Information System (INIS)

Richardson, J.A.; McKernan, S.A.; Vigil, M.J.

2003-01-01

Recently the Final Safety Analysis Report (FSAR) for the Plutonium Facility at Los Alamos National Laboratory, Technical Area 55 (TA-55) was revised and submitted to the US. Department of Energy (DOE). As a part of this effort, over seventy Process Hazards Analyses (PrHAs) were written and/or revised over the six years prior to the FSAR revision. TA-55 is a research, development, and production nuclear facility that primarily supports US. defense and space programs. Nuclear fuels and material research; material recovery, refining and analyses; and the casting, machining and fabrication of plutonium components are some of the activities conducted at TA-35. These operations involve a wide variety of industrial, chemical and nuclear hazards. Operational personnel along with safety analysts work as a team to prepare the PrHA. PrHAs describe the process; identi fy the hazards; and analyze hazards including determining hazard scenarios, their likelihood, and consequences. In addition, the interaction of the process to facility systems, structures and operational specific protective features are part of the PrHA. This information is rolled-up to determine bounding accidents and mitigating systems and structures. Further detailed accident analysis is performed for the bounding accidents and included in the FSAR. The FSAR is part of the Documented Safety Analysis (DSA) that defines the safety envelope for all facility operations in order to protect the worker, the public, and the environment. The DSA is in compliance with the US. Code of Federal Regulations, 10 CFR 830, Nuclear Safety Management and is approved by DOE. The DSA sets forth the bounding conditions necessary for the safe operation for the facility and is essentially a 'license to operate.' Safely of day-to-day operations is based on Hazard Control Plans (HCPs). Hazards are initially identified in the PrI-IA for the specific operation and act as input to the HCP. Specific protective features important to worker

A Study on the Requisite Information for Severe Accident Management

Energy Technology Data Exchange (ETDEWEB)

Park, Sunhee; Ahn, Kwang-Il; Kim, Jae-Hwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Related this research on arranging the requisite information for severe accident management, the documents of various forms in each country as well as the domestic literature are secured and analyzed. The analyzed information is arranged up to a detailed level. For the secured documents, the issued organizations and the issued purpose are diverse. Thus, the contents of the secured documents are also diverse according to the reactor type, and the purpose and standards of the classification are also diverse. Moreover, terminologies with same meaning are not unified. These various documents are analyzed to arrange the requisite information for severe accident management. Based on the documents of a related severe accident, the major information was analyzed. The information is different according to the reactor type, classification standard, and classification standard of the safety function. Thus the information is classified variously. In this study, based on the analysis results of the documents described these information, the major information and parameters are examined as safety function. And the results of parameters and information including the safety function and the detail information are induced.

Status of safety issues at licensed power plants

International Nuclear Information System (INIS)

1991-05-01

As part of ongoing US Nuclear Regulatory Commission (NRC) efforts to ensure the quality and accountability of safety issue information, a program has been established whereby an annual NUREG report will be published on the status of licensee implementation and NRC verification of safety issues in major NRC requirement areas. This report, the second volume of a three-volume series, addresses the status of unresolved safety issues (USIs) at licensed plants. The data contained in these NUREG reports are a product of the NRC's Safety Issues Management System (SIMS) database, which is maintained by the Project Management Staff in the Office of Nuclear Reactor Regulation and by NRC regional personnel. The purpose of this report is to provide a comprehensive description of the status of implementation and verification of the 27 safety issues designated as USIs and to make this information available to other interested parties, including the public. A corollary purpose of this NUREG report is to serve as a follow-on to NUREG-0933, ''A Prioritization of Generic Safety Issues,'' which tracks safety issues up until requirements are approved for imposition at licensed plants. 3 figs., 4 tabs

Hydrogen Safety Issues Compared to Safety Issues with Methane and Propane

International Nuclear Information System (INIS)

Green, Michael A.

2005-01-01

The hydrogen economy is not possible if the safety standards currently applied to liquid hydrogen and hydrogen gas by many laboratories are applied to devices that use either liquid or gaseous hydrogen. Methane and propane are commonly used by ordinary people without the special training. This report asks, 'How is hydrogen different from flammable gasses that are commonly being used all over the world?' This report compares the properties of hydrogen, methane and propane and how these properties may relate to safety when they are used in both the liquid and gaseous state. Through such an analysis, sensible safety standards for the large-scale (or even small-scale) use of liquid and gaseous hydrogen systems can be developed. This paper is meant to promote discussion of issues related to hydrogen safety so that engineers designing equipment can factor sensible safety standards into their designs

Hydrogen Safety Issues Compared to Safety Issues with Methane andPropane

Energy Technology Data Exchange (ETDEWEB)

Green, Michael A.

2005-08-20

The hydrogen economy is not possible if the safety standards currently applied to liquid hydrogen and hydrogen gas by many laboratories are applied to devices that use either liquid or gaseous hydrogen. Methane and propane are commonly used by ordinary people without the special training. This report asks, 'How is hydrogen different from flammable gasses that are commonly being used all over the world?' This report compares the properties of hydrogen, methane and propane and how these properties may relate to safety when they are used in both the liquid and gaseous state. Through such an analysis, sensible safety standards for the large-scale (or even small-scale) use of liquid and gaseous hydrogen systems can be developed. This paper is meant to promote discussion of issues related to hydrogen safety so that engineers designing equipment can factor sensible safety standards into their designs.

LMFBR safety. 2. Review of current issues and bibliography of literature, 1970--1972

International Nuclear Information System (INIS)

Buchanan, J.R.; Keilholtz, G.W.

1976-01-01

This report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1970 through 1972. The bibliography consists of approximately 1620 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness

LMFBR safety. 4. Review of current issues and bibliography of literature (1974--1975)

Energy Technology Data Exchange (ETDEWEB)

Buchanan, J.R.; Keilholtz, G.W.

1977-03-21

This report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1974 through 1975. The bibliography consists of approximately 1554 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness.

LMFBR safety. 4. Review of current issues and bibliography of literature (1974--1975)

International Nuclear Information System (INIS)

Buchanan, J.R.; Keilholtz, G.W.

1977-01-01

This report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1974 through 1975. The bibliography consists of approximately 1554 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness

LMFBR safety. 2. Review of current issues and bibliography of literature, 1970--1972

Energy Technology Data Exchange (ETDEWEB)

Buchanan, J.R.; Keilholtz, G.W.

1976-11-22

This report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1970 through 1972. The bibliography consists of approximately 1620 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness.

International Experts' Meeting on Decommissioning and Remediation after a Nuclear Accident. Presentations

International Nuclear Information System (INIS)

2013-01-01

Against the backdrop of the accident at TEPCO's Fukushima Daiichi nuclear power plant in March 2011, the Director General of the International Atomic Energy Agency (IAEA) convened the IAEA Ministerial Conference on Nuclear Safety in Vienna, Austria, in June 2011. The Conference adopted a Ministerial Declaration which, inter alia, requested the Director General to prepare a draft Action Plan covering all the relevant aspects relating to nuclear safety, emergency preparedness and response, and radiation protection of people and the environment, as well as the relevant international legal framework. On 22 September 2011, the IAEA General Conference unanimously endorsed the draft IAEA Action Plan on Nuclear Safety approved by the Board of Governors. The Action Plan sets out a comprehensive programme of work, in 12 major areas, to strengthen nuclear safety worldwide. Under one of these areas, headed 'Enhance transparency and effectiveness of communication and improve dissemination of information', the IAEA Secretariat was requested to organize an International Experts' Meeting (IEM) on decommissioning, cleanup and remediation of nuclear facilities and contaminated lands after a nuclear accident. This IEM was organized in response to that request. The IEM focussed on the complex technical, societal, environmental and economic issues that need to be considered for decommissioning and remediation activities after a nuclear accident, specifically after the emergency exposure situation of an accident has been declared ended. The objective of the IEM is to assist Member States to prepare for and to be able to manage the consequences resulting from a nuclear accident. The meeting highlighted the specific short term and long term issues that may need to be addressed during decommissioning of facilities and remediation of the off-site environment affected by a nuclear accident. It is of interest to a wide range of experts, such as decision makers, regulators, operators

Safety I-II, resilience and antifragility engineering: a debate explained through an accident occurring on a mobile elevating work platform.

Science.gov (United States)

Martinetti, Alberto; Chatzimichailidou, Maria Mikela; Maida, Luisa; van Dongen, Leo

2018-04-24

Occupational health and safety (OHS) represents an important field of exploration for the research community: in spite of the growth of technological innovations, the increasing complexity of systems involves critical issues in terms of degradation of the safety levels. In such a situation, new safety management approaches are now mandatory in order to face the safety implications of the current technological evolutions. Along these lines, performing risk-based analysis alone seems not to be enough anymore. The evaluation of robustness, antifragility and resilience of a socio-technical system is now indispensable in order to face unforeseen events. This article will briefly introduce the topics of Safety I and Safety II, resilience engineering and antifragility engineering, explaining correlations, overlapping aspects and synergies. Secondly, the article will discuss the applications of those paradigms to a real accident, highlighting how they can challenge, stimulate and inspire research for improving OHS conditions.

Synthesis of the IRSN report related to severe accidents and to the probabilistic level-2 safety study for the Flamanville EPR reactor. Referral of the Permanent Group of Experts for nuclear reactors (GPR), examination of probabilistic level-2 safety studies (EPS 2) and severe accidents (AG) of the Flamanville reactor nr 3. Opinion related to severe accidents and to the probabilistic level-2 safety study for the Flamanville EPR reactor (FA3). Electronuclear reactors - EDF - Flamanville 3 EPR reactor. Severe accidents and probabilistic level 2 studies

International Nuclear Information System (INIS)

2015-01-01

This document gathers several documents. The first one recalls the main arrangements implemented on the FA3 EPR reactor regarding accidents with core fusion, reports the analysis made by the IRSN about the sizing of these arrangements to reach a controlled status of the installation after a severe accident, regarding the probabilistic level-2 safety assessment, regarding the radiological impact of a severe accident on the population and on the environment, regarding those aimed at facing a total and long duration loss of electric power sources and cold sources, and about the situation of the reactor with respect to WENRA positions on severe accidents for new reactors. The second document is a letter sent by the ASN to the Permanent Group of Experts for nuclear reactors (GPR) to address probabilistic level-2 safety studies (EPS2) and severe accidents for the Flamanville 3 reactor. The third one reports the opinion of the GPR on these both issues and proposes a set of recommendations. The next document is a letter sent by the ASN to the Flamanville 3 project manager at EDF which recalls the related objectives, the ASN opinion on the implemented arrangements for severe accidents (de-pressurization of the primary circuit, management of hydrogen-related risks, corium recovery and cooling outside the vessel, limitation of vapour explosion risks outside the vessel, heat evacuation system, containment enclosure, management of the risk of a return to criticality), to face a total and long duration loss of electricity sources and cold sources, and other aspects addressed in the IRSN analysis. Requests and remarks formulated by the ASN are provided in an appendix to this last document

Safety Requirements / Design Criteria for SFR. Lessons Learned from the Fukushima Dai-ichi Accident

International Nuclear Information System (INIS)

Yllera, Javier

2013-01-01

After the Fukushima event (March 2011) the IAEA has started an action to review and revise, if necessary, all Safety Standards to take into consideration the lessons learned from the accident. The Safety Standards that need to be revised have been identified. A Prioritization Approach has been established: The first priority is to review safety guides applicable for NPPs and spent fuel storage with focus on the measures for the prevention and mitigation of severe accident due to external hazards - ● Regulatory framework, Safety assessment, Management system, Radiation protection and Emergency Preparedness and response; ● Sitting, Design, Operation of NPPs ● Decommissioning and Waste Management. Original sources for lessons learned: IAE fact Finding Mission, Japan´s report to the Ministerial Conference, INSAG Report, etc. Later, other lesson sources considered

Chernobyl and the safety of nuclear reactors in OECD countries

International Nuclear Information System (INIS)

1987-01-01

This report assesses the possible bearing of the Chernobyl accident on the safety of nuclear reactors in OECD countries. It discusses analyses of the accident performed in several countries as well as improvements to the safety of RBMK reactors announced by the USSR. Several remaining questions are identified. The report compares RBMK safety features with those of commercial reactors in OECD countries and evaluates a number of issues raised by the Chernobyl accident

ITER safety

International Nuclear Information System (INIS)

Raeder, J.; Piet, S.; Buende, R.

1991-01-01

As part of the series of publications by the IAEA that summarize the results of the Conceptual Design Activities for the ITER project, this document describes the ITER safety analyses. It contains an assessment of normal operation effluents, accident scenarios, plasma chamber safety, tritium system safety, magnet system safety, external loss of coolant and coolant flow problems, and a waste management assessment, while it describes the implementation of the safety approach for ITER. The document ends with a list of major conclusions, a set of topical remarks on technical safety issues, and recommendations for the Engineering Design Activities, safety considerations for siting ITER, and recommendations with regard to the safety issues for the R and D for ITER. Refs, figs and tabs

Reactor Safety Research: Semiannual report, January-June 1986: Reactor Safety Research Program

International Nuclear Information System (INIS)

1987-05-01

Sandia National Laboratories is conducting, under USNRC sponsorship, phenomenological research related to the safety of commercial nuclear power reactors. The research includes experiments to simulate the phenomenology of accident conditions and the development of analytical models, verified by experiment, which can be used to predict reactor and safety systems performance behavior under abnormal conditions. The objective of this work is to provide NRC requisite data bases and analytical methods to (1) identify and define safety issues, (2) understand the progression of risk-significant accident sequences, and (3) conduct safety assessments. The collective NRC-sponsored effort at Sandia National Laboratories is directed at enhancing the technology base supporting licensing decisions

The corporate quest for zero accidents: A case study into the response to safety transgressions in the industrial sector

NARCIS (Netherlands)

Twaalfhoven, S.F.M.; Kortleven, W.J.

2016-01-01

Since the 1990s, the idea that accidents should be reduced to zero is gaining growing acclaim in the fields of road safety and occupational safety and health. As most of the literature on this so-called Zero Accident Vision (ZAV) deals exclusively with its application to road safety, which is a

Editorial safety science special issue road safety management.

NARCIS (Netherlands)

Wegman, F.C.M. & Hagezieker, M.P.

2014-01-01

The articles presented in this Special Issue on Road Safety Management represent an illustration of the growing interest in policy-related research in the area of road safety. The complex nature of this type of research combined with the observation that scientific journals pay limited attention to

Technology, safety, and costs of decommissioning reference light-water reactors following postulated accidents. Appendices

Energy Technology Data Exchange (ETDEWEB)

Murphy, E S; Holter, G M

1982-11-01

Appendices contain information concerning the reference site description; reference PWR facility description; details of reference accident scenarios and resultant contamination levels; generic cleanup and decommissioning information; details of activities and manpower requirements for accident cleanup at a reference PWR; activities and manpower requirements for decommissioning at a reference PWR; costs of decommissioning at a reference PWR; cost estimating bases; safety assessment details; and details of post-accident cleanup and decommissioning at a reference BWR.

Lessons of TEPCO's Fukushima accident from human and organizational aspects and challenge for nuclear safety reform

International Nuclear Information System (INIS)

Kawano, Akira

2013-01-01

The author participated in international experts' meeting held by IAEA on May 21, 2013 and presented the paper focusing on human and organizational aspects of the Fukushima nuclear accident. It clarified TEPCO's basic recognition: 'The cause of the accident should not be treated merely as a natural disaster due to an enormous tsunami being something difficult to anticipate and we believe it is necessary to seriously acknowledge the result that TEPCO failed to avoid an accident which might have been avoided if ample preparations had been made in advance with thorough use of human intellect' and then reconsidered the Fukushima nuclear accident: 'could we predict an enormous tsunami and take whatever countermeasures?' and 'could we respond to the accident better?' for the worldwide operators to avoid such an accident, which moved meeting's participants deeply. Presentation's contents followed 'Reassessment of the Fukushima Nuclear Accident and Nuclear Safety Reform Plan' published by TEPCO on March 29. This article described outline of the presentation. Though the only way to explore the possibility to save Unit 1 was that operators could bravely go up to the 4th floor of reactor building and open the isolation valves to start IC, it was given up without any clear communication among key decision makers for confirming the IC operational status. As for Unit 3, operators could not achieve thorough focus on ensuring core cooling such that proactive transfer from RCIC/HPCI to low pressure water injection was not challenged, mainly because of low trust on Diesel/Driven Fire Protection Pump (DDFP). During the design stage and afterward, ample consideration was not given to common cause failures originating in external events, which led to a severe situation where almost all the power supplies and safety system functions were lost. Continuous efforts to reduce risks were not ample, including the collection, analysis and utilization of information on safety enhancement

Human error as the root cause of severe accidents at nuclear reactors

International Nuclear Information System (INIS)

Kovács Zoltán; Rýdzi, Stanislav

2017-01-01

A root cause is a factor inducing an undesirable event. It is feasible for root causes to be eliminated through technological process improvements. Human error was the root cause of all severe accidents at nuclear power plants. The TMI accident was caused by a series of human errors. The Chernobyl disaster occurred after a badly performed test of the turbogenerator at a reactor with design deficiencies, and in addition, the operators ignored the safety principles and disabled the safety systems. At Fukushima the tsunami risk was underestimated and the project failed to consider the specific issues of the site. The paper describes the severe accidents and points out the human errors that caused them. Also, provisions that might have eliminated those severe accidents are suggested. The fact that each severe accident occurred on a different type of reactor is relevant – no severe accident ever occurred twice at the same reactor type. The lessons learnt from the severe accidents and the safety measures implemented on reactor units all over the world seem to be effective. (orig.)

Accidents - Chernobyl accident; Accidents - accident de Tchernobyl

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

The analysis of pressurizer safety valve stuck open accident for low power and shutdown PSA

Energy Technology Data Exchange (ETDEWEB)

Lim, Ho Gon; Park, Jin Hee; Jang, Seong Chul; Kim, Tae Woon

2005-01-01

The PSV (Pressurizer Safety Valve) popping test carried out practically in the early phase of a refueling outage has a little possibility of triggering a test-induced LOCA due to a PSV not fully closed or stuck open. According to a KSNP (Korea Standard Nuclear Power Plant) low power and shutdown PSA (Probabilistic Safety Assessment), the failure of a HPSI (High Pressure Safety Injection) following a PSV stuck open was identified as a dominant accident sequence with a significant contribution to low power and shutdown risks. In this study, we aim to investigate the consequences of the NPP for the various accident sequences following the PSV stuck open as an initiating event through the thermal-hydraulic system code calculations. Also, we search the accident mitigation method for the sequence of HPSI failure, then, the applicability of the method is verified by the simulations using T/H system code.

Status of safety issues at licensed power plants

International Nuclear Information System (INIS)

1991-06-01

As part of ongoing US Nuclear Regulatory Commission (NRC) efforts to ensure the quality and accountability of safety issue information, a program has been established whereby an annual NUREG report will be published on the status of licensee implementation and NRC verification of safety issues in major NRC requirement areas. This report, the third volume of a three-volume series, addresses the status of generic safety issues (GSIs) at licensed plants. Volume 1 addressed the status of Three Mile Island Action Plan requirements and was published in March 1991. Volume 2 addressed the status of implementation and verification of unresolved safety issues and was published in May 1991. The annual NUREG report will combine these three areas in a single volume to be published in late 1991. The data contained in these NUREG reports are a product of the NRC's Safety Issues Management System (SIMS) database, which is maintained by the Project Management Staff in the Office of Nuclear Reactor Regulation and by NRC regional personnel. The purpose of this report is to provide a comprehensive description of the status of implementation and verification of the 34 GSIs and sub-issues that have been resolved by the NRC and involve implementation of an action or actions by licensees. This NUREG report also serves as a follow-on to NUREG-0933, ''A Prioritization of Generic Safety Issues,'' which tracks safety issues up until a request for action by licensees is issued by NRC. 3 figs., 6 tabs

Accomplishments and challenges of the severe accident research

International Nuclear Information System (INIS)

Sehga, B.R.

1998-01-01

This paper describes the progress of the severe accident research since 1980, in terms of the accomplishments made so far and the challenges that remain. Much has been accomplished: many important safety issues have been resolved and consensus is near on some others. However, some of the previously identified safety issues remain as challenges, while some new ones have arisen due to the shift in focus from containment integrity to vessel integrity. New reactor designs have also created some new challenges. In general, the regulatory demands in new reactor designs are much stricter, thereby requiring much greater attention to the safety issues concerned with the containment design of the new large reactors

Evaluation of strategies for severe accident prevention and mitigation

International Nuclear Information System (INIS)

Tokarz, R.

1989-01-01

The NRC is planning to establish regulatory oversight on severe accident management capability in the US nuclear reactor industry. Accident management includes certain preparatory and recovery measures that can be taken by the plant operating and technical personnel to prevent or mitigate the consequences of a severe accident. Following an initiating event, accident management strategies include measures to (1) prevent core damage, (2) arrest the core damage if it begins and retain the core inside the vessel, (3) maintain containment integrity if the vessel is breached, and (4) minimize offsite releases. Objectives of the NRC Severe Accident Management Program are to assure that technically sound strategies are identified and guidance to implement these strategies is provided to utilities. This paper will describe work performed to date by Pacific Northwest Laboratory (PNL) and Battelle Memorial Institute (BMI) relative to severe accident strategy evaluation, as well as work to be performed and expected results. Working with Brookhaven National Laboratory, PNL evaluated a series of NRC suggested accident management strategies. The evaluation of these strategies was divided between PNL and Brookhaven National Laboratory and a similar paper will be presented by Brookhaven regarding their strategy evaluation. This paper will stress the overall safety issues related to the research and emphasize the strategies that are applicable to major safety issues. The relationship of these research activities to other projects is discussed, as well as planning for future changes in the direction of work to be undertaken

Accident Assessment

International Nuclear Information System (INIS)

Tripputi, Ivo; Lund, Ingemar

2002-01-01

There is a general feeling that decommissioning is an activity involving limited risks, compared to NPP operation, and in particular risks involving the general public. This is technically confirmed by licensing analysis and evaluations, where, once the spent fuel has been removed from the plant, the radioactivity inventory available to be released to the environment is very limited. Decommissioning activities performed so far in the world have also confirmed the first assumptions and no specific issue has been identified, in this field, to justify a completely new approach. Commercial interests in international harmonization, which could drive an in-depth discussion about the bases of this approach, are weak at the moment. However, there are several reasons why a discussion in an international framework about the Safety Case for decommissioning (and, in particular, about Accident Assessment) may be considered necessary and important, and why it may show some specific and peculiar aspects. An effort for a comprehensive and systematic D and D accident safety assessment of the decommissioning process is justified. It is necessary also to explore in a holistic way the aspects of industrial safety, and develop tools for the decision-making process optimization. The expected results are the implementation of appropriate and optimized protective measures in any event and of adequate on/off-site emergency plans for optimal public and workers protection. The experience from other decommissioning projects and large-scale industrial activities is essential to balance provisions and an Operating Experience review process (specific for decommissioning) should help to focus on real issues

Meta-analysis of the effect of road safety campaigns on accidents.

Science.gov (United States)

Phillips, Ross Owen; Ulleberg, Pål; Vaa, Truls

2011-05-01

A meta-analysis of 67 studies evaluating the effect of road safety campaigns on accidents is reported. A total of 119 results were extracted from the studies, which were reported in 12 different countries between 1975 and 2007. After allowing for publication bias and heterogeneity of effects, the weighted average effect of road safety campaigns is a 9% reduction in accidents (with 95% confidence that the weighted average is between -12 and -6%). To account for the variability of effects measured across studies, data were collected to characterise aspects of the campaign and evaluation design associated with each effect, and analysed to identify a model of seven campaign factors for testing by meta-regression. The model was tested using both fixed and random effect meta-regression, and dependency among effects was accounted for by aggregation. These analyses suggest positive associations between accident reduction and the use of personal communication or roadside media as part of a campaign delivery strategy. Campaigns with a drink-driving theme were also associated with greater accident reductions, while some of the analyses suggested that accompanying enforcement and short campaign duration (less than one month) are beneficial. Overall the results are consistent with the idea that campaigns can be more effective in the short term if the message is delivered with personal communication in a way that is proximal in space and time to the behaviour targeted by the campaign. Copyright © 2011 Elsevier Ltd. All rights reserved.

Operational and environmental safety

International Nuclear Information System (INIS)

Anon.

1978-01-01

The responsibility of the DOE Office of Operational and Environmental Safety is to assure that DOE-controlled activities are conducted in a manner that will minimize risks to the public and employees and will provide protection for property and the environment. The program supports the various energy technologies by identifying and resolving safety problems; developing and issuing safety policies, standards, and criteria; assuring compliance with DOE, Federal, and state safety regulations; and establishing procedures for reporting and investigating accidents in DOE operations. Guidelines for the radiation protection of personnel; radiation monitoring at nuclear facilities; an assessment of criticality accidents by fault tree analysis; and the preparation of environmental, safety, and health standards applicable to geothermal energy development are discussed

Reperes, the information magazine of the Institute for Radiation Protection and Nuclear Safety - IRSN, No. 12 - January 2012, Special issue Fukushima - First lessons from the accident

International Nuclear Information System (INIS)

2012-01-01

A first set of articles addresses the nuclear crisis in Japan (description of the accident, information mission sent by France, and support actions undertaken by France in Japan in the fields of education, civilian security, culture, sailing, media, dosimeters, robotics). A second set discusses lessons learned in terms of nuclear safety (complementary safety assessments, stress test in Gravelines), radiological consequences (impact on Japanese population, the Symbiose software, the Teleray network), crisis management, and research

High-heat tank safety issue resolution program plan

International Nuclear Information System (INIS)

Wang, O.S.

1993-12-01

The purpose of this program plan is to provide a guide for selecting corrective actions that will mitigate and/or remediate the high-heat waste tank safety issue for single-shell tank (SST) 241-C-106. This program plan also outlines the logic for selecting approaches and tasks to mitigate and resolve the high-heat safety issue. The identified safety issue for high-heat tank 241-C-106 involves the potential release of nuclear waste to the environment as the result of heat-induced structural damage to the tank's concrete, if forced cooling is interrupted for extended periods. Currently, forced ventilation with added water to promote thermal conductivity and evaporation cooling is used to cool the waste. At this time, the only viable solution identified to resolve this safety issue is the removal of heat generating waste in the tank. This solution is being aggressively pursued as the permanent solution to this safety issue and also to support the present waste retrieval plan. Tank 241-C-106 has been selected as the first SST for retrieval. The program plan has three parts. The first part establishes program objectives and defines safety issues, drivers, and resolution criteria and strategy. The second part evaluates the high-heat safety issue and its mitigation and remediation methods and alternatives according to resolution logic. The third part identifies major tasks and alternatives for mitigation and resolution of the safety issue. Selected tasks and best-estimate schedules are also summarized in the program plan

Enhancement of Nuclear Safety in Korea: A Regulatory Perspective

International Nuclear Information System (INIS)

Chung, K.Y.

2016-01-01

In the aftermath of Fukushima Daiichi accident in 2011 Korean regulatory body immediately performed special inspections on nuclear power plants (NPPs) and a research reactor in Korea, and issued an enforcement order for the licensees to implement fifty Fukushima action items to address the safety issues identified by the inspections. Subsequently, the licensees have established the implementation plans for resolution of the action items. By the implementation of the action items, the possibility of severe accident due to the extreme hazards has been greatly reduced and the capabilities to mitigate the severe accident, should it occur, have been upgraded. To improve the consistency and predictability of the regulation on severe accidents, Nuclear Safety and Security Commission (NSSC) the regulatory body in Korea, is revising the regulatory framework for severe accidents. The new framework will require the licensee to enhance the capabilities for prevention and mitigation of severe accidents in view of the defence in depth principle, to assess the radiological effects from the severe accidents, and to improve current accident management procedures and guidelines necessary for the prevention and mitigation of severe accidents. This rulemaking also considers the safety principles provided by the IAEA Vienna Declaration in 2015, which require new NPPs to prevent large radioactive releases. (author)

Young people and snowmobiling in northern Norway: accidents, injury prevention and safety strategies.

Science.gov (United States)

Mehus, Grete; Mehus, Alf Gunnar; Germeten, Sidsel; Henriksen, Nils

2016-01-01

Snowmobiling among young people in Scandinavia frequently leads to accidents and injuries. Systematic studies of accidents exist, but few studies have addressed young drivers' experiences. The aim of this article is to reveal how young people experience and interpret accidents, and to outline a prevention strategy. Thirty-one girls and 50 boys aged 16-23 years from secondary schools in Northern Norway and on Svalbard, a Norwegian archipelago in the Arctic Ocean, participated in 17 focus groups segregated by gender. A content analysis identified themes addressing the research questions. Participants described risk as being inherent to snowmobiling, and claimed that accidents followed from poor risk assessment, careless driving or mishaps. Evaluation of accidents and recommendations for preventive measures varied. Girls acknowledged the risks and wanted knowledge about outdoor life, navigation and external risks. Boys underestimated or downplayed the risks, and wanted knowledge about safety precautions while freeriding. Both genders were aware of how and why accidents occurred, and took precautions. Boys tended to challenge norms in ways that contradict the promotion of safe driving behaviour. Stories of internal justice regarding driving under the influence of alcohol occurred. Adolescents are aware of how accidents occur and how to avoid them. Injury prevention strategies should include a general population strategy and a high-risk strategy targeted at extreme risk-seekers. Drivers, snowmobilers' organisations and the community should share local knowledge in an effort to define problem areas, set priorities and develop and implement preventive measures. Risk prevention should include preparation of safe tracks and focus on safety equipment and safe driving behaviour, but should also pay increased attention to the potential of strengthening normative regulation within peer groups regarding driving behaviour and mutual responsibility for preventing accidents.

Technology, safety and costs of decommissioning reference light water reactors following postulated accidents

International Nuclear Information System (INIS)

Konzek, G.J.; Smith, R.I.

1990-12-01

The estimated costs for post-accident cleanup at the reference BWR (developed previously in NUREG/CR-2601, Technology, Safety and Costs of Decommissioning Reference Light Water Reactors Following Postulated Accidents) are updated to January 1989 dollars in this report. A simple formula for escalating post-accident cleanup costs is also presented. Accident cleanup following the most severe accident described in NUREG/CR-2601 (i.e., the Scenario 3 accident) is estimated to cost from $1.22 to 1.44 billion, in 1989 dollars, for assumed escalation rates of 4% or 8% in the years following 1989. The time to accomplish cleanup remained unchanged from the 8.3 years originally estimated. No reanalysis of current information on the technical aspects of TMI-2 cleanup has been performed. Only the cost of inflation has been evaluated since the original PNL analysis was completed. 32 refs., 12 tabs

Strengthening Regulatory Effectiveness in India – Lessons Learnt from Fukushima Accident

International Nuclear Information System (INIS)

Solanki, R.

2016-01-01

Following the Fukushima Daiichi accident in Japan, one of the most important lessons learnt, among other things, was the issue of strengthening the effectiveness of the regulatory bodies. Immediately after the Fukushima accident, National level safety audits were conducted on all operating NPPs in India to review safety of NPPs in India. A national action plan has been prepared to implement the identified short term, midterm and long term measures. The assessment indicates that national response to the Fukushima Accident for safety assessment of NPPs and subsequent actions and initiatives taken for safety enhancement of the NPPs in India are in-line with the objectives of the IAEA Action plan. This paper highlights the actions taken by India in the light of Fukushima Daiichi accident in order to strengthen the regulatory effectiveness through improvements in the existing core processes, challenges faced, Insights gained from the recent initiatives on safety performance indicators and assessment of safety culture, relevant observations of IRRS mission report and Indian perspectives on the further cooperation among the member states for enhancing the regulatory effectiveness for nuclear oversight of regulated organizations. (author)

Risk reduction category (RRC-A) accident studies in the safety analysis report of the EPR trademark reactor

International Nuclear Information System (INIS)

Poehlmann, M.; Bleher, G.; Ismaier, A.; Knoll, A.; Levi, P.; Garcia, E. Vera; Schels, A.; Seitz, H.; Lima Campos, L.

2013-01-01

The Risk Reduction Category (RRC-A) is considered in the safety demonstration of nuclear reactors in addition to design basis operating conditions (Plant Condition Category, PCC), in order to analyze with a risk reduction approach any operating conditions with multiple failures. As extending the operating conditions of the plant 'beyond design basis', the Risk Reduction Category (RRC-A) is also denoted as Design Extension Condition (DEC-A). In the German licensing framework, the RRCA (or DEC-A) transients correspond to safety assessment level '4b' of the 'Sicherheitsanforderungen an Kernkraftwerke' (Safety Requirements for Nuclear Power Plants), Az. RS I 5 - 13303/01 of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety. These RRC-A (or DEC-A) operating conditions require specific design provisions (implemented by manual or automatic action), known as RRC-A measures, intended to render consequences of accumulated failures admissible. In contrast, RRC-B constitute severe accidents that lead to core melt. Identification of RRC-A operating conditions and corresponding RRC-A measures is based on the use of results of probabilistic safety assessments. After the Fukushima accident the RRC-A accidents like Station Black Out (SBO) or Loss of Ultimate Heat Sink (LUHS) are of particular interest in the safety assessment of nuclear new builds. In several chapters of the Safety Analysis Report it is demonstrated that the AREVA EPRTM design is resistant at RRC-A accident conditions. (orig.)

Management of severe accidents

International Nuclear Information System (INIS)

Jankowski, M.W.

1987-01-01

The definition and the multidimensionality aspects of accident management have been reviewed. The suggested elements in the development of a programme for severe accident management have been identified and discussed. The strategies concentrate on the two tiered approaches. Operative management utilizes the plant's equipment and operators capabilities. The recovery managment concevtrates on preserving the containment, or delaying its failure, inhibiting the release, and on strategies once there has been a release. The inspiration for this paper was an excellent overview report on perspectives on managing severe accidents in commercial nuclear power plants and extending plant operating procedures into the severe accident regime; and by the most recent publication of the International Nuclear Safety Advisory Group (INSAG) considering the question of risk reduction and source term reduction through accident prevention, management and mitigation. The latter document concludes that 'active development of accident management measures by plant personnel can lead to very large reductions in source terms and risk', and goes further in considering and formulating the key issue: 'The most fruitful path to follow in reducing risk even further is through the planning of accident management.' (author)

Management of severe accidents

International Nuclear Information System (INIS)

Jankowski, M.W.

1988-01-01

The definition and the multidimensionality aspects of accident management have been reviewed. The suggested elements in the development of a programme for severe accident management have been identified and discussed. The strategies concentrate on the two tiered approaches. Operative management utilizes the plant's equipment and operators capabilities. The recovery management concentrates on preserving the containment, or delaying its failure, inhibiting the release, and on strategies once there has been a release. The inspiration for this paper was an excellent overview report on perspectives on managing severe accidents in commercial nuclear power plants and extending plant operating procedures into the severe accident regime; and by the most recent publication of the International Nuclear Safety Advisory Group (INSAG) considering the question of risk reduction and source term reduction through accident prevention, management and mitigation. The latter document concludes that active development of accident management measures by plant personnel can lead to very large reductions in source terms and risk, and goes further in considering and formulating the key issue: The most fruitful path to follow in reducing risk even further is through the planning of accident management

Applicability of Phebus FP results to severe accident safety evaluations and management measures

International Nuclear Information System (INIS)

Schwarz, M.; Clement, B.; Jones, A.V.

2001-01-01

The international Phebus FP (Fission Product) programme is the largest research programme in the world investigating core degradation and radioactive product release should a core meltdown accident occur in a light water reactor plant. Three integral experiments have already been performed. The experimental database obtained so far contains a wealth of information to validate the computer codes used for safety and accident management assessment

Recent and current activities of the OECD/NEA Working Group on Fuel Safety (NEA/CSNI). Recent and Current Activities of the Working Group on Fuel Safety (NEA/CSNI)

International Nuclear Information System (INIS)

Petit, Marc

2013-01-01

The Working Group on Fuel Safety (WGFS) is part of the Committee on the Safety of Nuclear Installations (CSNI) of the Nuclear Energy Agency and has the main mission of advancing the current understanding and addressing fuel safety issues. Recent and current activities of the working group have addressed mainly the loss of coolant accident (LOCA), the reactivity initiated accident (RIA), the fuel safety criteria and leaking fuel issues, as well as Fukushima-related fuel topics. In the area of LOCA, the group issued different documents, the most notable being a very comprehensive state of the art report [NEA/CSNI/R (2009)15]. Regarding RIA, some documents were finalised and issued in the recent years, as well as a state of the art report [NEA/CSNI/R (2010)1]. The question of leaking fuel and how it is handled in the reactors is an activity that is just starting. Of particular interest to people developing new fuel concepts is the Nuclear Fuel Safety Criteria Technical Review - Second Edition [NEA/CSNI/R (2012)3]. This document provides a broad overview of the numerous criteria used in the NEA member countries to demonstrate to safe use of fuel in light water reactors. The WGFS has started discussions about fuel related issues raised by the Fukushima accident, in particular, hydrogen production. New concepts have been proposed to solve these issues but it appears that these concepts will need to go through a long qualification process to assess their adequacy for the different situations considered in the evaluation of fuel safety, from normal operation to accident conditions

LMFBR accident delineation study: approach and preliminary results

International Nuclear Information System (INIS)

Williams, D.C.; Sholtis, J.A.; Rios, M.; Worledge, D.H.; Conrad, P.W.; Varela, D.W.; Pickard, P.S.

1979-01-01

Event trees have been constructed for all phases of LMFBR accidents. The trees proved useful for identifying meaningful initiating accident categories and containment responses. In these areas, quantification appears feasible, given an adequate data base. Event trees were also used to represent in-core phenomenological questions governing accident progression and energetics, but here quantification appears impracticable because pervasive phenomenological uncertainties exist. Infrequent accident initiation is the dominant factor in assuring low risk. Nevertheless, containment promises an additional measure of risk reduction provided severe energetics are highly unlikely. The delineation served to systematize LMFBR safety issues and should aid in evaluating LMFBR R and D priorities

The experiences of research reactor accident to safety improvement

International Nuclear Information System (INIS)

Wiranto, S.

1999-01-01

The safety of reactor operation is the main factor in order that the nuclear technology development program can be held according the expected target. Several experience with research reactor incidents must be learned and understood by the nuclear program personnel, especially for operators and supervisors of RSG-GA. Siwabessy. From the incident experience of research reactor in the world, which mentioned in the book 'Experience with research reactor incidents' by IAEA, 1995, was concluded that the main cause of research reactor accidents is understandless about the safety culture by the nuclear installation personnel. With learn, understand and compare between this experiences and the condition of RSG GA Siwabessy is expended the operators and supervisors more attention about the safety culture, so that RSG GA Siwabessy can be operated successfull, safely according the expected target

Unsolved issues related to thermal-hydraulics in the suppression chamber during Fukushima Daiichi accident progressions

International Nuclear Information System (INIS)

Mizokami, Shinya; Yamada, Daichi; Honda, Takeshi; Yamauchi, Daisuke; Yamanaka, Yasunori

2016-01-01

On 11 March 2011, the Great East Japan Earthquake and Tsunami hit the Fukushima Daiichi Nuclear Power Station. The Fukushima Daiichi Units 1-3 lost all DC and AC power supplies, which set in motion a chain of events that led to releases of radioactivity to the environment. Since then, TEPCO has made many efforts to investigate the accident progressions and the status of the reactors and containment vessels. However, there still exist several tens of unsolved issues to be investigated for the fully understanding of the accident. In this paper, we introduce the unsolved issues related to thermal-hydraulics in the suppression chamber during the Fukushima Daiichi accident progressions. Especially, in Units 2 and 3, there are possibilities that thermal stratification inside their suppression chambers played an important role. It is important that these phenomena are addressed following both theoretical and experimental approaches as support to severe accident simulations. (author)

Development of accident event trees and evaluation of safety system failure modes for the nuclear ultra large crude carrier

International Nuclear Information System (INIS)

Lewe, C.K.; Coffey, R.S.; Goodwin, E.F.; Maltese, J.G.; Pyatt, D.W.

1978-01-01

A method of applying the probabilistic accident event tree methodology to safety assessments of a nuclear powered Ultra Large Crude Carrier is presented. Also presented are the procedures by which an external accident initiating event, such as a ship collision, may be correlated with the probabilities of damage to the ship's safety systems and to their ultimate availabilities to perform required safety functions

Database on aircraft accidents

International Nuclear Information System (INIS)

Nishio, Masahide; Koriyama, Tamio

2013-11-01

The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' as the standard method for evaluating probability of aircraft crash into nuclear reactor facilities in July 2002. In response to this issue, Japan Nuclear Energy Safety Organization has been collecting open information on aircraft accidents of commercial airplanes, self-defense force (SDF) airplanes and US force airplanes every year since 2003, sorting out them and developing the database of aircraft accidents for the latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. In this report the database was revised by adding aircraft accidents in 2011 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2012 database for the latest 20 years from 1992 to 2011. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for the latest 20 years from 1992 to 2011 to evaluate probability of aircraft crash into reactor facilities. The method for developing the database of aircraft accidents to evaluate probability of aircraft crash into reactor facilities is based on the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' described above. The 2012 revised database for the latest 20 years from 1992 to 2011 shows the followings. The trend of the 2012 database changes little as compared to the last year's report. (1) The data of commercial aircraft accidents is based on 'Aircraft accident investigation reports of Japan transport safety board' of Ministry of Land, Infrastructure, Transport and Tourism. The number of commercial aircraft accidents is 4 for large fixed-wing aircraft, 58 for small fixed-wing aircraft, 5 for large bladed aircraft and 99 for small bladed aircraft. The relevant accidents

International aspects of nuclear accidents

International Nuclear Information System (INIS)

Uematsu, K.

1989-09-01

The accident at Chernobyl revealed that there were shortcomings and gaps in the existing international mechanisms and brought home to governments the need for stronger measures to provide better protection against the risks of severe accidents. The main thrust of international co-operation with regard to nuclear safety issues is aimed at achieving a uniformly high level of safety in nuclear power plants through continuous exchanges of research findings and feedback from reactor operating experience. The second type of problem posed in the event of an accident resulting in radioactive contamination of several countries relates to the obligation to notify details of the circumstances and nature of the accident speedily so that the countries affected can take appropriate protective measures and, if necessary, organize mutual assistance. Giving the public accurate information is also an important aspect of managing an emergency situation arising from a severe accident. Finally, the confusion resulting from the unwarranted variety of protective measures implemented after the Chernobyl accident has highlighted the need for international harmonization of the principles and scientific criteria applicable to the protection of the public in the event of an accident and for a more consistent approach to emergency plans. The international conventions on third party liability in the nuclear energy sector (Paris/Brussels Conventions and the Vienna Convention) provide for compensation for damage caused by nuclear accidents in accordance with the rules and jurisdiction that they lay down. These provisions impose obligations on the operator responsible for an accident, and the State where the nuclear facility is located, towards the victims of damage caused in another country

MDEP Design-Specific Common Position CP-APR1400WG-01. Common position addressing Fukushima Daiichi nuclear power plant accident

International Nuclear Information System (INIS)

2016-05-01

The MDEP APR1400 Working Group (APR1400WG) members consist of members from Republic of Korea, United Arab Emirates, and the United States. A main objectives of MDEP is to encourage convergence of code, standard and safety goals with exploring the opportunities for harmonization of regulatory practice and cooperation on safety review of APR-1400 specific designs. This common position addressing is aimed at sharing knowledge, information and experience on safety improvement related to lessons learned from the Fukushima Daiichi NPP Accident or Fukushima Daiichi NPP Accident-related issues amongst APR-1400 WG member states to achieve the MEDP goal. Because not all of these Regulators have completed the regulatory review of their APR1400 applications yet, this paper identifies common preliminary approaches to address potential safety improvements for APR1400 plants, as well as common general expectations for new nuclear power plants, as related to lessons learned from the Fukushima Daiichi NPP Accident or Fukushima Daiichi NPP Accident-related issues. While some asymmetry exists among those of three Regulators in terms of design, regulatory practice and licensing milestone sharing information and common understanding on post-Fukushima Daiichi NPP Accident enhancement would be promote resilient design for countering beyond design extreme external event like Fukushima Daiichi NPP nuclear disaster. This common position paper aims at identifying characteristics of post-Fukushima Daiichi NPP Accident enhancements putting in place by each country and setting common position to achieve balanced and harmonized APR-1400 design. After the safety reviews of the APR1400 design applications that are currently in review are completed, the regulators will update this paper to reflect their safety conclusions regarding the APR1400 design and how the design could be enhanced to address Fukushima Daiichi NPP Accident-related issues. The common preliminary approaches are organised into

A Comparative Analysis of the Impact of the IAEA Cooperation Instruments in the Field of Nuclear Safety to Deal with the Fukushima Daiichi Accident vis-a-vis the Chernobyl Accident

International Nuclear Information System (INIS)

Da Silva Simões, V.

2016-01-01

On 26 April 1986, an explosion at Unit 4 at the Chernobyl nuclear power plant released a very large amount of radioactive material into the atmosphere. According to the conclusions raised at the “International Forum on Chernobyl´s Nuclear Safety Aspects” held in Vienna from 1 to 3 April 1996, two important causes of the accident were that: “there were significant deficiencies in the design of the reactor – in particular of its shutdown system – and operating procedures were severely violated at the time of the accident” and “there was a lack of safety culture in the organizations responsible for operation and for control: important safety weaknesses had been recognized long before the accident occurred but were not remedied.” Only thanks to the discovery of an increase in environmental radioactivity in Nordic countries the international community was informed about the accident. On 11 March 2011, as one of the consequences of the tsunami waves generated by the Great East Japan Earthquake off the Pacific coast of Japan, the Fukushima Daiichi nuclear power plant accident took place. In his statement to the “International Conference on Chernobyl: Twenty-Five Years On - Safety for the Future” the International Atomic Energy Agency Director General, Mr. Yukiya Amano, pointed out “Chernobyl led to a great step forward in international cooperation in the field of nuclear safety. We now have four safety conventions, two Codes of Conduct, fundamental safety principles and a body of globally recognised IAEA Safety Standards.” [ ] “An international coordinated response system, with the IAEA's Incident and Emergency Centre at its heart, is now in place.” [ ] “We also have an IAEA peer review system, based on the Agency's Safety Standards.” But Mr. Amano also recognized that “despite the great progress made in the last 25 years, more needs to be done to ensure that a ''Safety First'' approach becomes fully

Hospital safety climate surveys: measurement issues.

Science.gov (United States)

Jackson, Jeanette; Sarac, Cakil; Flin, Rhona

2010-12-01

Organizational safety culture relates to behavioural norms in the workplace and is usually assessed by safety climate surveys. These can be a diagnostic indicator on the state of safety in a hospital. This review examines recent studies using staff surveys of hospital safety climate, focussing on measurement issues. Four questionnaires (hospital survey on patient safety culture, safety attitudes questionnaire, patient safety climate in healthcare organizations, hospital safety climate scale), with acceptable psychometric properties, are now applied across countries and clinical settings. Comparisons for benchmarking must be made with caution in case of questionnaire modifications. Increasing attention is being paid to the unit and hospital level wherein distinct cultures may be located, as well as to associated measurement and study design issues. Predictive validity of safety climate is tested against safety behaviours/outcomes, with some relationships reported, although effects may be specific to professional groups/units. Few studies test the role of intervening variables that could influence the effect of climate on outcomes. Hospital climate studies are becoming a key component of healthcare safety management systems. Large datasets have established more reliable instruments that allow a more focussed investigation of the role of culture in the improvement and maintenance of staff's safety perceptions within units, as well as within hospitals.

Impact of the accident at TMI-2 on new safety regulations

International Nuclear Information System (INIS)

Collins, J.T.

1981-01-01

The Nuclear Regulatory Commission (NRC) has been very busy, since the accident, looking into the causes surrounding the events that occurred on the morning of March 28, 1979. To date, the Commission has implemented the Short-Term Lessons Learned and has provided a schedule for implementing the Long-Term Lessons Learned. Some of these requirements have resulted in delays in licensing of new plants and the temporary shutdown of some operating plants. However, the NRC believes these new requirements are essential to increase the safety of nuclear power plants and to protect the health and safety of the public. Although the accident occurred almost 19 months ago, the cleanup of TMI-2 continues and will continue for the next 5 to 7 years. As the cleanup progresses and ultimately the fuel removed, the Commission will continue to learn from the information generated by this program. This information will be factored into the licensing process. If nuclear power is to remain a viable option as a source of electrical power in the United States, then NRC must continue to assure the general public that these plants can be operated safely from the lessons learned at TMI and that systems required to mitigate the consequences of accidents will indeed perform their intended functions

Task Force Report, Safety of Personnel in LHC underground areas following the accident of 19th September 2008

CERN Document Server

Delille, B; Inigo-Golfin, J; Lindell, G; Roy, G; Tavian, L; Thomas, E; Trant, R; Völlinger, C

2009-01-01

In January 2009, the Task Force on Safety of Personnel in the LHC underground areas following the accident in sector 3-4 of 19th September 2008 (Safety Task Force) received from the CERN Director General the mandate to investigate the impact of the accident of 19th September 2008 on the safety of personnel working in the LHC underground areas. This mandate includes the elaboration of preventive and/or corrective measures, if deemed necessary. This report gives the conclusions and recommendations of the Safety Task Force which have been reviewed by an external advisory committee of safety experts.

SARNET. Severe Accident Research Network - key issues in the area of source term

International Nuclear Information System (INIS)

Giordano, P.; Micaelli, J.C.; Haste, T.; Herranz, L.

2005-01-01

About fifty European organisations integrate in SARNET (Network of Excellence of the EU 6 th Framework Programme) their research capacities in resolve better the most important remaining uncertainties and safety issues concerning existing and future Nuclear Power Plants (NPPs) under hypothetical Severe Accident (SA) conditions. Wishing to maintain a long-lasting cooperation, they conduct three types of activities: integrating activities, spreading of excellence and jointly executed research. This paper summarises the main results obtained by the network after the first year, giving more prominence to those from jointly executed research in the Source Term area. Integrating activities have been performed through different means: the ASTEC integral computer code for severe accident transient modelling, through development of PSA2 methodologies, through the setting of a structure for definition of evolving R and D priorities and through the development of a web-network of data bases that hosts experimental data. Such activities have been facilitated by the development of an Advanced Communication Tool. Concerning spreading of excellence, educational courses covering Severe Accident Analysis Methodology and Level 2 PSA have been set up, to be given in early 2006. A detailed text book on Severe Accident Phenomenology has been designed and agreed amongst SARNET members. A mobility programme for students and young researchers is being developed, some detachments are already completed or in progress, and examples are quoted. Jointly executed research activities concern key issues grouped in the Corium, Containment and Source Term areas. In Source Term, behaviour of the highly radio-toxic ruthenium under oxidising conditions (like air ingress) for HBU and MOX fuel has been investigated. First modelling proposals for ASTEC have been made for oxidation of fuel and of ruthenium. Experiments on transport of highly volatile oxide ruthenium species have been performed. Reactor

Study On Safety Analysis Of PWR Reactor Core In Transient And Severe Accident Conditions

International Nuclear Information System (INIS)

Le Dai Dien; Hoang Minh Giang; Nguyen Thi Thanh Thuy; Nguyen Thi Tu Oanh; Le Thi Thu; Pham Tuan Nam; Tran Van Trung; Le Van Hong; Vo Thi Huong

2014-01-01

The cooperation research project on the Study on Safety Analysis of PWR Reactor Core in Transient and Severe Accident Conditions between Institute for Nuclear Science and Technology (INST), VINATOM and Korean Atomic Energy Research Institute (KAERI), Korea has been setup to strengthen the capability of researches in nuclear safety not only in mastering the methods and computer codes, but also in qualifying of young researchers in the field of nuclear safety analysis. Through the studies on the using of thermal hydraulics computer codes like RELAP5, COBRA, FLUENT and CFX the thermal hydraulics research group has made progress in the research including problems for safety analysis of APR1400 nuclear reactor, PIRT methodologies and sub-channel analysis. The study of severe accidents has been started by using MELCOR in collaboration with KAERI experts and the training on the fundamental phenomena occurred in postulated severe accident. For Vietnam side, VVER-1000 nuclear reactor is also intensively studied. The design of core catcher, reactor containment and severe accident management are the main tasks concerning VVER technology. The research results are presented in the 9 th National Conference on Mechanics, Ha Noi, December 8-9, 2012, the 10 th National Conference on Nuclear Science and Technology, Vung Tau, August 14-15, 2013, as well as published in the journal of Nuclear Science and Technology, Vietnam Nuclear Society and other journals. The skills and experience from using computer codes like RELAP5, MELCOR, ANSYS and COBRA in nuclear safety analysis are improved with the nuclear reactors APR1400, Westinghouse 4 loop PWR and especially the VVER-1000 chosen for the specific studies. During cooperation research project, man power and capability of Nuclear Safety center of INST have been strengthen. Three masters were graduated, 2 researchers are engaging in Ph.D course at Hanoi University of Science and Technology and University of Science and Technology, Korea

Environmental and safety issues of the fusion fuel cycle

International Nuclear Information System (INIS)

Crocker, J.G.

1980-01-01

This paper discusses the environmental and safety concerns inherent in the development of fusion energy, and the current Department of Energy programs seeking to: (1) develop safe and reliable techniques for tritium control; (2) reduce the quantity of activation products produced; and (3) provide designs to limit the potential for accidents that could result in release of radioactive materials. Because of the inherent safety features of fusion and the early start that has been made in safety problem recognition and solution, fusion should be among the lower risk technologies for generation of commercial power

Progress in Nuclear Safety Reform of TEPCO

International Nuclear Information System (INIS)

Kawano, A.

2016-01-01

On March 29, 2014, TEPCO issued the Nuclear Safety Reform Plan describing the background cause of our Fukushima Nuclear Accident and our plan to challenge organizational and cultural change to avoid recurrence of such a tragic accident and to pursue the excellence in safety. This report will reflect that background cause with some specific examples and introduce how we are currently implementing this reform plan.

RA reactor safety analysis, Part II - Accident analysis; Analiza sigurnosti rada Reaktora RA I-III, Deo II - Analiza akcidenta

Energy Technology Data Exchange (ETDEWEB)

Raisic, N; Radanovic, Lj; Milovanovic, M; Afgan, N; Kulundzic, P [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

1963-02-15

This part of the RA reactor safety analysis includes analysis of possible accidents caused by failures of the reactor devices and errors during reactor operation. Two types of accidents are analyzed: accidents resulting from uncontrolled reactivity increase, and accidents caused by interruption of cooling.

Impact of the TMI accident on the French nuclear program and the safety analysis

International Nuclear Information System (INIS)

Fourest, B.; Boaretto, Y.; Cayol, A.; Droulers, Y.; Goudal, M.; Oury, J.M.

1980-04-01

Almost immediately after the TMI accident, Electricite de France (EdF), Framatome and the French safety authorities started a large scale program of actions designed to analyse and understand the causes of the accident, and draw lessons applicable in France. This paper discusses these actions and the main conclusions of TMI accident analysis in France, notably: the fundamental role of plant operators, and the importance of operator training, written instructions and procedures, and diagnostic aids; the importance of feeding back operating experience to design teams, and incorporating the results of accident and post-accident studies in operating procedures; the necessity to improve knowledge of core cooling modes, including during two-phase flow and natural circulation; measures to improve particular systems and components [fr