WorldWideScience

Sample records for accident investigation

  1. Supervisor's accident investigation handbook

    This pamphlet was prepared by the Environmental Health and Safety Department (EH and S) of Lawrence Berkeley Laboratory (LBL) to provide LBL supervisors with a handy reference to LBL's accident investigation program. The publication supplements the Accident and Emergencies section of LBL's Regulations and Procedures Manual, Pub. 201. The present guide discusses only accidents that are to be investigated by the supervisor. These accidents are classified as Type C by the Department of Energy (DOE) and include most occupational injuries and illnesses, government motor-vehicle accidents, and property damages of less than $50,000

  2. 29 CFR 1960.29 - Accident investigation.

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Accident investigation. 1960.29 Section 1960.29 Labor... MATTERS Inspection and Abatement § 1960.29 Accident investigation. (a) While all accidents should be investigated, including accidents involving property damage only, the extent of such investigation shall...

  3. Accident/Mishap Investigation System

    Keller, Richard; Wolfe, Shawn; Gawdiak, Yuri; Carvalho, Robert; Panontin, Tina; Williams, James; Sturken, Ian

    2007-01-01

    InvestigationOrganizer (IO) is a Web-based collaborative information system that integrates the generic functionality of a database, a document repository, a semantic hypermedia browser, and a rule-based inference system with specialized modeling and visualization functionality to support accident/mishap investigation teams. This accessible, online structure is designed to support investigators by allowing them to make explicit, shared, and meaningful links among evidence, causal models, findings, and recommendations.

  4. Deepwater Horizon Accident Investigation Report

    NONE

    2010-09-15

    On the evening of April 20, 2010, a well control event allowed hydrocarbons to escape from the Macondo well onto Transocean's Deepwater Horizon, resulting in explosions and fire on the rig. Eleven people lost their lives, and 17 others were injured. The fire, which was fed by hydrocarbons from the well, continued for 36 hours until the rig sank. Hydrocarbons continued to flow from the reservoir through the wellbore and the blowout preventer (BOP) for 87 days, causing a spill of national significance. BP Exploration and Production Inc. was the lease operator of Mississippi Canyon Block 252, which contains the Macondo well. BP formed an investigation team that was charged with gathering the facts surrounding the accident, analyzing available information to identify possible causes and making recommendations to enable prevention of similar accidents in the future. The BP investigation team began its work immediately in the aftermath of the accident, working independently from other BP spill response activities and organizations. The ability to gather information was limited by a scarcity of physical evidence and restricted access to potentially relevant witnesses. The team had access to partial real-time data from the rig, documents from various aspects of the Macondo well's development and construction, witness interviews and testimony from public hearings. The team used the information that was made available by other companies, including Transocean, Halliburton and Cameron. Over the course of the investigation, the team involved over 50 internal and external specialists from a variety of fields: safety, operations, subsea, drilling, well control, cementing, well flow dynamic modeling, BOP systems and process hazard analysis. This report presents an analysis of the events leading up to the accident, eight key findings related to the causal chain of events and recommendations to enable the prevention of a similar accident. The investigation team worked

  5. Deepwater Horizon Accident Investigation Report

    On the evening of April 20, 2010, a well control event allowed hydrocarbons to escape from the Macondo well onto Transocean's Deepwater Horizon, resulting in explosions and fire on the rig. Eleven people lost their lives, and 17 others were injured. The fire, which was fed by hydrocarbons from the well, continued for 36 hours until the rig sank. Hydrocarbons continued to flow from the reservoir through the wellbore and the blowout preventer (BOP) for 87 days, causing a spill of national significance. BP Exploration and Production Inc. was the lease operator of Mississippi Canyon Block 252, which contains the Macondo well. BP formed an investigation team that was charged with gathering the facts surrounding the accident, analyzing available information to identify possible causes and making recommendations to enable prevention of similar accidents in the future. The BP investigation team began its work immediately in the aftermath of the accident, working independently from other BP spill response activities and organizations. The ability to gather information was limited by a scarcity of physical evidence and restricted access to potentially relevant witnesses. The team had access to partial real-time data from the rig, documents from various aspects of the Macondo well's development and construction, witness interviews and testimony from public hearings. The team used the information that was made available by other companies, including Transocean, Halliburton and Cameron. Over the course of the investigation, the team involved over 50 internal and external specialists from a variety of fields: safety, operations, subsea, drilling, well control, cementing, well flow dynamic modeling, BOP systems and process hazard analysis. This report presents an analysis of the events leading up to the accident, eight key findings related to the causal chain of events and recommendations to enable the prevention of a similar accident. The investigation team worked separately

  6. Lessons learned from accidents investigations

    Accidents from three main practices: medical applications, industrial radiography and industrial irradiators are used to illustrate some common causes of accidents and the main lessons to be learned. A brief description of some of these accidents is given. Lessons learned from the described accidents are approached by subjects covering: safety culture, quality assurance, human factors, good engineering practice, defence in depth, security of sources, safety assessment and monitoring and verification compliance. (author)

  7. Lessons learned from accident investigations

    Accidents in three main practices - medical applications, industrial radiography and industrial irradiators - are used to illustrate some common causes of accidents and the main lessons to be learned from them. A brief description of some of these accidents is given. Lessons learned from the accidents described are approached bearing in mind: safety culture, quality assurance, human factors, good engineering practice, defence in depth, security of sources, safety assessment and monitoring and verification compliance. (author)

  8. 14 CFR 415.41 - Accident investigation plan.

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Accident investigation plan. 415.41 Section... Launch Range § 415.41 Accident investigation plan. An applicant must file an accident investigation plan... reporting and responding to launch accidents, launch incidents, or other mishaps, as defined by § 401.5...

  9. Independent accident investigation: a modern safety tool

    Historically, safety has been subjected to a fragmented approach. In the past, every department has had its own responsibility towards safety, focusing either on working conditions, internal safety, external safety, rescue and emergency, public order or security. They each issued policy documents, which in their time were leading statements for elaboration and regulation. They also addressed safety issues with tools of various nature, often specifically developed within their domain. Due to a series of major accidents and disasters, the focus of attention is shifting from complying with quantitative risk standards towards intervention in primary operational processes, coping with systemic deficiencies and a more integrated assessment of safety in its societal context. In The Netherlands recognition of the importance of independent investigations has led to an expansion of this philosophy from the transport sector to other sectors. The philosophy now covers transport, industry, defense, natural disaster, environment and health and other major occurrences such as explosions, fires, and collapse of buildings or structures. In 2003 a multi-sector covering law will establish an independent safety board in The Netherlands. At a European level, mandatory investigation agencies are recognized as indispensable safety instruments for aviation, railways and the maritime sector, for which EU Directives are in place or being progressed [Transport accident and incident investigation in the European Union, European Transport Safety Council, ISBN 90-76024-10-3, Brussel, 2001]. Due to a series of major events, attention has been drawn to the consequences of disasters, highlighting the involvement of rescue and emergency services. They also have become subjected to investigative efforts, which in return, puts demands on investigation methodology. This paper comments on an evolutionary development in safety thinking and of safety boards, highlighting some consequences for strategic

  10. ACCOUNT OF ROAD CONDITIONS WHILE INVESTIGATING TRAFFIC ACCIDENTS

    D. D. Selioukov; I. I. Leonovich

    2014-01-01

    The paper considers problems on better traffic safety at government, authority, engineering and driver activity levels, account of road conditions while investigating traffic accidents. The paper also provides road defects mentioned in forensic transport examinations of traffic accidents.

  11. Strategies for dealing with resistance to recommendations from accident investigations

    Lundberg, J.; Rollenhagen, C.; Hollnagel, E.;

    2012-01-01

    Accident investigation reports usually lead to a set of recommendations for change. These recommendations are, however, sometimes resisted for reasons such as various aspects of ethics and power. When accident investigators are aware of this, they use several strategies to overcome the resistance....... This paper describes strategies for dealing with four different types of resistance to change. The strategies were derived from qualitative analysis of 25 interviews with Swedish accident investigators from seven application domains. The main contribution of the paper is a better understanding of...... effective strategies for achieving change associated with accident investigation. (C) 2011 Elsevier Ltd. All rights reserved....

  12. Understanding accident investigators : a study of the required skills and behaviours for effective UK inspectors of accidents

    Flaherty, Sarah

    2008-01-01

    In the UK, accidents associated with maritime, aviation and rail transport are conducted by the Inspectors of Accidents at the Marine, Air and Rail Accident Investigation Branches. A review of current academic literature provides little insight into the qualities and attributes essential for the role of accident investigator. A wealth of material exists about accidents themselves but as yet, a study into the profile of the accident investigator has not been conducted. This research soug...

  13. Research investigation report on Fukushima Daiichi nuclear accident

    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)

  14. Aeromedical Lessons Learned from the Space Shuttle Columbia Accident Investigation

    Chandler, Mike

    2011-01-01

    This slide presentation provides an update on the Columbia accident response presented in 2005 with additional information that was not available at that time. It will provide information on the following topics: (1) medical response and Search and Rescue, (2) medico-legal issues associated with the accident, (3) the Spacecraft Crew Survival Integrated Investigation Team Report published in 2008, and (4) future NASA flight surgeon spacecraft accident response training.

  15. Safety investigation of team performance in accidents

    The paper presents the capacities of the performance evaluation of teamwork (PET) method. Its practicability and efficiency are illustrated by retrospective human reliability analyse of the famous nuclear and maritime accidents. A quantitative assessment of operators' performance on the base of thermo-hydraulic (T/H) calculations and full-scope simulator data for set of NPP design basic accidents with WWER is demonstrated. The last data are obtained on the 'WWER-1000' full-scope simulator of Kozloduy NPP during the regular practical training of the operators' teams. An outlook on the 'evaluation system of main control room (MCR) operators' reliability' project, based on simulator data of operators' training is given

  16. The medical investigation of airship accidents.

    Stahl, C J; McMeekin, R R; Ruehle, C J; Canik, J J

    1988-07-01

    A review of the autopsy reports for 18 of 21 victims in 3 of the 4 nonrigid Navy airship accidents during the period 1955 to 1966 revealed that the patterns of injury, complicated by postcrash entrapment, immersion, or fire, are similar to the injuries observed in the low-speed, low-altitude crashes of rigid airships and of light aircraft. With the renewed interest in the development of airships for military purposes, there is a need for improved design related to crashworthiness and to aircrew habitability, safety, restraint, and egress in order to enhance the chance for survival in the event of an accident. PMID:3171506

  17. Safety investigation of team performance in accidents.

    Petkov, G; Todorov, V; Takov, T; Petrov, V; Stoychev, K; Vladimirov, V; Chukov, I

    2004-07-26

    The paper presents the capacities of the performance evaluation of teamwork (PET) method. Its practicability and efficiency are illustrated by retrospective human reliability analyse of the famous nuclear and maritime accidents. A quantitative assessment of operators' performance on the base of thermo-hydraulic (T/H) calculations and full-scope simulator data for set of NPP design basic accidents with WWER is demonstrated. The last data are obtained on the 'WWER-1000' full-scope simulator of Kozloduy NPP during the regular practical training of the operators' teams. An outlook on the "evaluation system of main control room (MCR) operators' reliability" project, based on simulator data of operators' training is given. PMID:15231353

  18. Investigation of accident management strategies for VVER-1000-Type reactors

    The goal of this work is the search for an optimal accident management strategy to prevent containment failure and to stop the core/concrete interaction from hindering cavity bottom melt-through on the one hand and from ending the ex-vessel source term increase on the other hand, i.e., to terminate the accident. The work is based on the results of previous studies of physical and chemical phenomena during different accident scenarios for VVER-1000-type reactors. For a TMLB' sequence (an accident caused by a transient in which core melt occurs because the electric power cannot be restored before the pressure vessel melts through), a number of calculations were performed using the source term code package (STCP) to investigate the influence of several accident management measures on the core/concrete interaction and the containment integrity

  19. Investigation of the core melt accident in light water reactors

    In the thesis the core melt accident, heating up and collapsing of the reactor core were investigated. The most important parameters of influence were found and their effect on the development of the accident were shown. A causal diagram was developed representing the great number of events occurring in the course of the core melt accident as well as their mutual dependences. Models were developed and applied for a detailed description of the collapse process, melting of materials, heat and material transport at flow-off of the melted mass and for taking into account steam blocking in the destroyed core sections. (orig.)

  20. A Tool for Safety Officers Investigating " simple" Accidents

    Jørgensen, Kirsten

    2010-01-01

    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...

  1. Investigation of VVER 1000 Fuel Behavior in Severe Accident Condition

    This paper presents the results obtained during a simulation of fuel behavior with the MELCOR computer code in case of severe accident for the VVER reactor core. The work is focused on investigating the influence of some important parameters, such as porosity, on fuel behavior starting from oxidation of the fuel cladding, fusion product release in the primary circuit after rupture of the fuel cladding, melting of the fuel and reactor core internals and its further relocation to the bottom of the reactor vessel. In the analyses are modeled options for blockage of melt and debris during its relocation. In the work is investigated the uncertainty margin of reactor vessel failure based on modeling of the reactor core and an investigation of its behavior. This is achieved by performing sensitivity analyses for VVER 1000 reactor core with gadolinium fuel type. The paper presents part of the work performed at the Institute for Nuclear Research and Nuclear Energy (INRNE) in the frame of severe accident research. The performed work continues the effort in the modeling of fuel behavior during severe accidents such as Station Blackout sequence for VVER 1000 reactors based on parametric study. The work is oriented towards the investigation of fuel behavior during severe accident conditions starting from the initial phase of fuel damaging through melting and relocation of fuel elements and reactor internals until the late in-vessel phase, when melt and debris are relocated almost entirely on the bottom head of the reactor vessel. The received results can be used in support of PSA2 as well as in support of analytical validation of Sever Accident Management Guidance for VVER 1000 reactors. The main objectives of this work area better understanding of fuel behavior during severe accident conditions as well as plant response in such situations. (author)

  2. Investigation on accident management measures for VVER-1000 reactors

    A consequence of a total loss of AC power supply (station blackout) leading to unavailability of major active safety systems which could not perform their safety functions is that the safety criteria ensuring a secure operation of the nuclear power plant would be violated and a consequent core heat-up with possible core degradation would occur. Currently, a study which examines the thermal-hydraulic behaviour of the plant during the early phase of the scenario is being performed. This paper focuses on the possibilities for delay or mitigation of the accident sequence to progress into a severe one by applying Accident Management Measures (AMM). The strategy 'Primary circuit depressurization' as a basic strategy, which is realized in the management of severe accidents is being investigated. By reducing the load over the vessel under severe accident conditions, prerequisites for maintaining the integrity of the primary circuit are being created. The time-margins for operators' intervention as key issues are being also assessed. The task is accomplished by applying the GRS thermal-hydraulic system code ATHLET. In addition, a comparative analysis of the accident progression for a station blackout event for both a reference German PWR and a reference VVER-1000, taking into account the plant specifics, is being performed. (authors)

  3. Integral Test Facility PKL: Experimental PWR Accident Investigation

    Klaus Umminger

    2012-01-01

    Full Text Available Investigations of the thermal-hydraulic behavior of pressurized water reactors under accident conditions have been carried out in the PKL test facility at AREVA NP in Erlangen, Germany for many years. The PKL facility models the entire primary side and significant parts of the secondary side of a pressurized water reactor (PWR at a height scale of 1 : 1. Volumes, power ratings and mass flows are scaled with a ratio of 1 : 145. The experimental facility consists of 4 primary loops with circulation pumps and steam generators (SGs arranged symmetrically around the reactor pressure vessel (RPV. The investigations carried out encompass a very broad spectrum from accident scenario simulations with large, medium, and small breaks, over the investigation of shutdown procedures after a wide variety of accidents, to the systematic investigation of complex thermal-hydraulic phenomena. This paper presents a survey of test objectives and programs carried out to date. It also describes the test facility in its present state. Some important results obtained over the years with focus on investigations carried out since the beginning of the international cooperation are exemplarily discussed.

  4. An investigation on body displacement after two drowning accidents.

    Mateus, Marcos; de Pablo, Hilda; Vaz, Nuno

    2013-06-10

    The finding of human remains in aquatic environments is usually attributed to causes such as work-related or recreational accidents, suicides, discarded homicide victims, and natural disasters. When the point and date of entry in the water is unknown, these findings pose serious challenges to forensic analysis given the difficulty to estimate the drift of the body. In this context, the information retrieved from cases where the point of entry and body recovery sites are known, as well as the timing, is significant. Two drowning accidents in marine coastal waters were analyzed. In both cases the post-mortem submersion interval (PMSI) is known, as well as the accident (point of entry) and body recovery sites. Accumulated degree days (ADD) was estimated in both cases using satellite sea surface temperature data. In both cases the bodies were recovered in the vicinity of the accident site (~2 km in case 1 and less than 1 km in case 2). Results were interpreted in terms of oceanographic conditions, physical settings and ADD. The results provide some relevant clues on the fate of human cadavers in coastal marine environments that can be used by officials and agencies involved in the recovery of bodies, as well as by forensic investigators when dealing with these findings. PMID:23578843

  5. Introduction of the Space Shuttle Columbia Accident, Investigation Details, Findings and Crew Survival Investigation Report

    Chandler, Michael

    2010-01-01

    As the Space Shuttle Program comes to an end, it is important that the lessons learned from the Columbia accident be captured and understood by those who will be developing future aerospace programs and supporting current programs. Aeromedical lessons learned from the Accident were presented at AsMA in 2005. This Panel will update that information, closeout the lessons learned, provide additional information on the accident and provide suggestions for the future. To set the stage, an overview of the accident is required. The Space Shuttle Columbia was returning to Earth with a crew of seven astronauts on 1Feb, 2003. It disintegrated along a track extending from California to Louisiana and observers along part of the track filmed the breakup of Columbia. Debris was recovered from Littlefield, Texas to Fort Polk, Louisiana, along a 567 statute mile track; the largest ever recorded debris field. The Columbia Accident Investigation Board (CAIB) concluded its investigation in August 2003, and released their findings in a report published in February 2004. NASA recognized the importance of capturing the lessons learned from the loss of Columbia and her crew and the Space Shuttle Program managers commissioned the Spacecraft Crew Survival Integrated Investigation Team (SCSIIT) to accomplish this. Their task was to perform a comprehensive analysis of the accident, focusing on factors and events affecting crew survival, and to develop recommendations for improving crew survival, including the design features, equipment, training and procedures intended to protect the crew. NASA released the Columbia Crew Survival Investigation Report in December 2008. Key personnel have been assembled to give you an overview of the Space Shuttle Columbia accident, the medical response, the medico-legal issues, the SCSIIT findings and recommendations and future NASA flight surgeon spacecraft accident response training. Educational Objectives: Set the stage for the Panel to address the

  6. Investigation of Key Factors for Accident Severity at Railroad Grade Crossings by Using a Logit Model

    Hu, Shou-Ren; Li, Chin-Shang; Lee, Chi-Kang

    2010-01-01

    Although several studies have used logit or probit models and their variants to fit data of accident severity on roadway segments, few have investigated accident severity at a railroad grade crossing (RGC). Compared to accident risk analysis in terms of accident frequency and severity of a highway system, investigation of the factors contributing to traffic accidents at an RGC may be more complicated because of additional highway–railway interactions. Because the proportional odds assumption ...

  7. Investigation of air cleaning system response to accident conditions

    Air cleaning system response to the stress of accident conditions are being investigated. A program overview and hghlight recent results of our investigation are presented. The program includes both analytical and experimental investigations. Computer codes for predicting effects of tornados, explosions, fires, and material transport are described. The test facilities used to obtain supportive experimental data to define structural integrity and confinement effectiveness of ventilation system components are described. Examples of experimental results for code verification, blower response to tornado transients, and filter response to tornado and explosion transients are reported

  8. Investigation of air cleaning system response to accident conditions

    We are investigating air cleaning system response to the stress of accident conditions. In this paper we present a program overview and highlight recent results of our investigations. The program includes both analytical and experimental investigations. Computer codes for predicting effects of tornados, explosions, fires, and material transport are described. We also describe the test facilities we use to obtain supportive experimental data to define structural integrity and confinement effectiveness of ventilation system components. Examples of experimental results for code verification, blower response to tornado transients, and filter response to tornado and explosion transients are reported

  9. Techniques and Tools of NASA's Space Shuttle Columbia Accident Investigation

    McDanels, Steve J.

    2005-01-01

    The Space Shuttle Columbia accident investigation was a fusion of many disciplines into a single effort. From the recovery and reconstruction of the debris, Figure 1, to the analysis, both destructive and nondestructive, of chemical and metallurgical samples, Figure 2, a multitude of analytical techniques and tools were employed. Destructive and non-destructive testing were utilized in tandem to determine if a breach in the left wing of the Orbiter had occurred, and if so, the path of the resultant high temperature plasma flow. Nondestructive analysis included topometric scanning, laser mapping, and real-time radiography. These techniques were useful in constructing a three dimensional virtual representation of the reconstruction project, specifically the left wing leading edge reinforced carbon/carbon heat protectant panels. Similarly, they were beneficial in determining where sampling should be performed on the debris. Analytic testing included such techniques as Energy Dispersive Electron Microprobe Analysis (EMPA), Electron Spectroscopy Chemical Analysis (ESCA), and X-Ray dot mapping; these techniques related the characteristics of intermetallics deposited on the leading edge of the left wing adjacent to the location of a suspected plasma breach during reentry. The methods and results of the various analyses, along with their implications into the accident, are discussed, along with the findings and recommendations of the Columbia Accident Investigation Board. Likewise, NASA's Return To Flight efforts are highlighted.

  10. Investigation on Nodalization for Analysis of SFR Channel Blockage Accidents

    Chang, Won Pyo; Kwon, Young Min; Ha, Ki Suk; Lee, Kwi Lim; Jeong, Hae Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    The present paper demonstrates nodalization analysis results obtained in application of the MATRA-LMR/FB to channel blockage accidents for a SFR (Sodium cooled Fast Reactor), KALIMER-150. In the earlier study, a uniform node size over the total sub-channel length in a subassembly was used. The study was carried out not only for the radially different positions, i.e. central, medium between the center and the duct wall, and edge sub-channels in the assembly, but also for larger blockage sizes larger than 6 sub-channels, the blockage size of which was classified into a DBE(Design Basis Event) in the KALIMER-150 design. The present investigation focuses mainly on the identification of conservatism as well as consistency in the analyses of the maximum coolant temperature for the 6 sub-channels blockage accidents

  11. Criticality accident in uranium fuel processing plant. Influence of the critical accident seen to consciousness investigation of the public

    Here was introduced a consciousness investigation result carried out at Fukui prefecture and Osaka city after about two months of the JCO criticality accident. Peoples were disturbed by the accident, and not a little changed their individual estimations on items relating to energy. However, peoples lived in Fukui prefecture did not increase rate of opposition against nuclear energy promotion and nuclear power plant construction to their living area on comparison with a year before the accident. This reason might be understood by that the accident was not an accident of a nuclear power plant directly, and that their living area was much distant from place of the accident and was not suffered any danger. On the other hand, public opinion in Osaka city made worse on comparison with that before a year, and if such worse public opinion was thought to be due to the accident, its effect could be said to be different in each area even with no direct relation to the accident to shown a result dependent upon its various conditions. As a rough tendency on psychological disturbance due to the accident, it could be said that peoples became to have feelings of avoiding hard nuclear energy technology at a chance of the accident and to direct thoughts of soft natural energy and environment respect. (G.K.)

  12. 49 CFR 837.3 - Published reports, material contained in the public accident investigation dockets, and accident...

    2010-10-01

    .... For information regarding the types of documents routinely issued by the Board, see 49 CFR part 801... public accident investigation dockets, and accident database data. 837.3 Section 837.3 Transportation... OF RECORDS IN LEGAL PROCEEDINGS § 837.3 Published reports, material contained in the public...

  13. An investigation of construction accidents in Rwanda: Perspectives from Kigali

    Cokeham, M; Tutesigensi, A

    2013-01-01

    The International Labour Organization suggests that measuring accident statistics is the first step in reducing accident numbers. However, many developing countries, especially in sub-Saharan Africa, including Rwanda, do not record accident statistics. In response to this, a questionnaire survey of 130 construction workers was undertaken in Kigali, the capital of the Republic of Rwanda, to raise awareness of construction accidents within the country. The survey generated information about 482...

  14. Investigation of Qom Rural Area Water Network Accident in 2010 and Minimization Approaches of Accident Frequencies

    Hossein Jafari Mansoorian

    2016-02-01

    Full Text Available Background & Aims of the Study : Accidents in water networks can lead to increase the uncounted water, costs of repair, maintenance, restoration and enter water contaminants to water network. The aim of this study is to survey the accidents of Qom rural water network and choose the right approaches to reduce the number of accidents. Materials & Methods: In this cross-sectional study, four sector of Qom province (Markazi, Dastjerd, Kahak and Qahan, were assessed over a period of 8 months (July – January 2010. This study was conducted through questionnaire of Ministry of Energy. Results: The total number of accidents was 763. The highest number of accidents in the four sectors was related to Markazi sector with 228 accidents. According to the time of the accident, the highest and lowest number of accident was related to September (19.7% and November (6.8%, respectively. According to the location of the accident on network, the highest and lowest number of accident was related to distribution network (64% and connections (17.5% and transmission pipe (18.34%, respectively. According to the type of the accident, the highest and lowest number of accident was related to breaking (47.8% and gasket failure (1.2%, respectively. Considering with the pipes’ material, the highest and lowest number of accident was related to polyethylene pipes (93% and steel and cast iron pipes (0.5%, 0.5%, respectively. Conclusions: Due to the high break rate of Polyethylene pipes, it is recommended to be placed in priority of leak detection and rehabilitation.   .

  15. Investigation of Qom Rural Area Water Network Accident in 2010 and Minimization Approaches of Accident Frequencies

    Hossein Jafari Mansoorian; Ahmad Reza Yari; Mohsen Ansari; Shahram Nazari; Mohamad Saberi Bidgoli; Gharib Majidi

    2016-01-01

    Background & Aims of the Study : Accidents in water networks can lead to increase the uncounted water, costs of repair, maintenance, restoration and enter water contaminants to water network. The aim of this study is to survey the accidents of Qom rural water network and choose the right approaches to reduce the number of accidents. Materials & Methods: In this cross-sectional study, four sector of Qom province (Markazi, Dastjerd, Kahak and Qahan), were assessed over a period of 8 mon...

  16. Accident investigation practices in Europe--main responses from a recent study of accidents in industry and transport

    Europe has during recent years been shocked by disasters from natural events and technical breakdowns. The consequences have been comprehensive, measured by lost lives, injuries, and material and environmental damage. ESReDA wanted in 2000 - by setting up a special expert group on accident investigation - to clarify the state of art of accident investigation practices and to map the use of thoroughly accident investigation in order to learn lessons from past disasters and prevent new ones. The scope was to cover three sectors in the society: transport, production processes and storage of hazardous materials, and energy production. The main method used was a questionnaire, which was sent in 2001 to about 150 organisations. About 50 replies were analysed. The replies showed great variations but also similarities, among others in definition of accident and incident, the objectives of the investigation team, criteria used to start an investigation, the status of the investigation organisation, the flow of information, the composition of the investigation team, and the use of internal or international procedures or rules. Several methods (in total 14 different methods were mentioned) were used for carrying out accident /incident investigations. Most of the respondents were willing to co-operate in one or another way with ESReDA. Although there are important biases in the material, the results from questionnaire are important inputs to the future work of ESReDA Expert group in this field. 3 safety approaches have been identified

  17. Investigation of adolescent accident predictive variables in hilly regions.

    Mohanty, Malaya; Gupta, Ankit

    2016-09-01

    The study aims to determine the significant personal and environmental factors in predicting the adolescent accidents in the hilly regions taking into account two cities Hamirpur and Dharamshala, which lie at an average elevation of 700--1000 metres above the mean sea level (MSL). Detailed comparisons between the results of 2 cities are also studied. The results are analyzed to provide the list of most significant factors responsible for adolescent accidents. Data were collected from different schools and colleges of the city with the help of a questionnaire survey. Around 690 responses from Hamirpur and 460 responses from Dharamshala were taken for study and analysis. Standard deviations (SD) of various factors affecting accidents were calculated and factors with relatively very low SD were discarded and other variables were considered for correlations. Correlation was developed using Kendall's-tau and chi-square tests and factors those were found significant were used for modelling. They were - the victim's age, the character of road, the speed of vehicle, and the use of helmet for Hamirpur and for Dharamshala, the kind of vehicle involved was an added variable found responsible for adolescent accidents. A logistic regression was performed to know the effect of each category present in a variable on the occurrence of accidents. Though the age and the speed of vehicle were considered to be important factors for accident occurrence according to Indian accident data records, even the use of helmet comes out as a major concern. The age group of 15-18 and 18-21 years were found to be more susceptible to accidents than the higher age groups. Due to the presence of hilly area, the character of road becomes a major concern for cause of accidents and the topography of the area makes the kind of vehicle involved as a major variable for determining the severity of accidents. PMID:26077876

  18. Cavity Heating Experiments Supporting Shuttle Columbia Accident Investigation

    Everhart, Joel L.; Berger, Karen T.; Bey, Kim S.; Merski, N. Ronald; Wood, William A.

    2011-01-01

    The two-color thermographic phosphor method has been used to map the local heating augmentation of scaled idealized cavities at conditions simulating the windward surface of the Shuttle Orbiter Columbia during flight STS-107. Two experiments initiated in support of the Columbia Accident Investigation were conducted in the Langley 20-Inch Mach 6 Tunnel. Generally, the first test series evaluated open (length-to-depth less than 10) rectangular cavity geometries proposed as possible damage scenarios resulting from foam and ice impact during launch at several discrete locations on the vehicle windward surface, though some closed (length-to-depth greater than 13) geometries were briefly examined. The second test series was designed to parametrically evaluate heating augmentation in closed rectangular cavities. The tests were conducted under laminar cavity entry conditions over a range of local boundary layer edge-flow parameters typical of re-entry. Cavity design parameters were developed using laminar computational predictions, while the experimental boundary layer state conditions were inferred from the heating measurements. An analysis of the aeroheating caused by cavities allowed exclusion of non-breeching damage from the possible loss scenarios being considered during the investigation.

  19. Investigation into information flow during the accident at Three Mile Island

    This report was prepared in response to a request from NRC Chairman Ahearne that directed the Office of Inspection and Enforcement to resume its investigation of information flow during the accident at Three Mile Island (TMI) that occurred on March 28, 1979. This investigation was resumed on March 21, 1980. The transfer of information among individuals, agencies, and personnel from Metropolitan Edison was analyzed to ascertain what knowledge was held by various individuals of the specific events, parameters, and systems during the accident at TMI. Maximum use was made of existing records, and additional interviews were conducted to clarify areas that had not been pursued during earlier investigations. Although the passage of time between the accident and post-accident interviews hampered precise recollections of events and circumstances, the investigation revealed that information was not intentionally withheld during the accident and that the system for effective transfer of information was inadequate during the accident

  20. Data Mining of Causal Relations from Text: Analysing Maritime Accident Investigation Reports

    Tirunagari, Santosh

    2015-01-01

    Text mining is a process of extracting information of interest from text. Such a method includes techniques from various areas such as Information Retrieval (IR), Natural Language Processing (NLP), and Information Extraction (IE). In this study, text mining methods are applied to extract causal relations from maritime accident investigation reports collected from the Marine Accident Investigation Branch (MAIB). These causal relations provide information on various mechanisms behind accidents,...

  1. Proposal for computer investigation of LMFBR core meltdown accidents

    The environmental consequences of an LMFBR accident involving breach of containment are so severe that such accidents must not be allowed to happen. Present methods for analyzing hypothetical core disruptive accidents like a loss of flow with failure to scram cannot show conclusively that such accidents do not lead to a rupture of the pressure vessel. A major deficiency of present methods is their inability to follow large motions of a molten LMFBR core. Such motions may lead to a secondary supercritical configuration with a subsequent energy release that is sufficient to rupture the pressure vessel. The Los Alamos Scientific Laboratory proposes to develop a computer program for describing the dynamics of hypothetical accidents. This computer program will utilize implicit Eulerian fluid dynamics methods coupled with a time-dependent transport theory description of the neutronic behavior. This program will be capable of following core motions until a stable coolable configuration is reached. Survey calculations of reactor accidents with a variety of initiating events will be performed for reactors under current design to assess the safety of such reactors

  2. Investigation of the management of the wastes from plant accident

    The accident in Fukushima Daiichi Nuclear Power Plant discharged large amount of radio-nuclides and contaminated wide areas in and out of the site. The decontamination, storage, treatment and disposal of generated wastes are now under planning. Though regulations for the radioactive wastes arisen from normal operation and decommissioning of nuclear facilities have been prepared, it is necessary to make amendment of those regulations to deal with wastes from the severe accident which may have much different features on nuclides contents, or possible accompanying hazardous chemical materials. Characteristics of wastes from accidents in foreign nuclear installations, and the treatment and the disposal of those wastes were surveyed by literature and radionuclide migration from the assumed temporally storage yards of the disaster debris was analyzed for consideration of future regulation. (author)

  3. Aspects Concerning The Rules And The Investigation Of Traffic Accidents As Work Accidents

    Tarnu, Lucian Ioan

    2015-07-01

    When Romania joined the European Union, it was imposed that the Romanian legislation in the field of the security and health at work be in line with the European one. The concept of health as it is defined by the International Body of Health, refers to a good physical, mental and social condition. The improvement of the activity of preventing the traffic accidents as work accidents must have as basis the correct and accurate evaluation of risks of getting injured. The goal of the activity of prevention and protection is to ensure the best working conditions, the prevention of accidents and occupational diseases and the adjustment to the scientific and technological progress. In the road transport sector, as in any other sector, it is very important to pay attention to working conditions to ensure a workforce motivated and well qualified. Some features make it a more difficult sector risk management than other sectors. However, if one takes into account how it works in practice this sector and the characteristics of drivers and how they work routinely, risks, dangers and threats can be managed efficiently and with great success.

  4. Investigations on pressure suppression system loads at accident conditions

    For simulation of the integral behavior of pressure suppresion systems at accident conditions a mathematical model was developed which simulates a wide range of the loads occurring during a loss-of coolant accident. The multi-zone point model DRASYS serves for mathematical simulation of quasistatic (pressure and temperature build-up in the dry well and the suppression chamber) as well as dynamic loads (free-blowing process, water throw-up and condensing oscillations) in the course of a loss-of-coolant accident. For determination of the state variations with time in the individual pressure sections thermodynamic equilibrium is assumed between steam and water phases. Thermal non-equilibrium states are taken into account if phase separation interfaces between water and steam/air mixture exist. The flows between the individual pressure sections are treated as homogeneous, nonsteady, incompressible flows. For verification of the mathematical model recalculations were made of experiments performed at various test stands. Teh recalculations showed that the mathematical model has got a wide range of application and is suited for design and assessment of pressure suppression systems at accident conditions. (orig.)

  5. Investigation report on criticality accident at the Uranium Processing Plant of the JCO, Ltd

    This report is a summarized one of investigation results on a criticality accident at the Uranium Processing Plant of the JCO, Ltd., carried out by the Nuclear Safety Investigation Special Group (SISG) of the Atomic Energy Society of Japan (AESJ). AESJ published a statement of the president on this accident on October 8, 1999, and decided to perform its investigation under SISG. SISG carried out some questionnaires for new trials together with conventional lectures of the well-informed. This report contains six chapters on critical safety and accident, process of the accident and elucidation of its facts, cause analysis and picking-out on problems, questionnaires on improvement proposal', questionnaires on 'duty of AESJ7, and future efforts on nuclear safety culture. At the last chapter, SISG discussed about some items on re-occurrence protection of the nuclear accident. (G.K.)

  6. Experimental investigations on nuclear aerosols in a severe accident

    DELGADO TARDÁGUILA, ROSARIO

    2016-01-01

    [EN] In case of a severe accident in a NPP fission products are released from the degraded fuel and may reach the environment if their confinement is lost and/or bypassed. Given the high radio-toxic nature of nuclear aerosols for environment and population, their unrestricted release should be absolutely avoided. One particular situation is the core meltdown sequence with steam generator tube rupture (SGTR). The containment bypass turns this sequence into an indispensable scenario to mode...

  7. Psychophysiological and other factors affecting human performance in accident prevention and investigation

    Psychophysiological factors are not uncommon terms in the aviation incident/accident investigation sequence where human error is involved. It is highly suspect that the same psychophysiological factors may also exist in the industrial arena where operator personnel function; but, there is little evidence in literature indicating how management and subordinates cope with these factors to prevent or reduce accidents. It is apparent that human factors psychophysological training is quite evident in the aviation industry. However, while the industrial arena appears to analyze psychophysiological factors in accident investigations, there is little evidence that established training programs exist for supervisors and operator personnel

  8. The Fukushima Daiichi nuclear accident final report of the AESJ investigation committee

    Atomic Energy Society of Japan

    2015-01-01

    The Magnitude 9 Great East Japan Earthquake on March 11, 2011, followed by a massive tsunami struck  TEPCO’s Fukushima Daiichi Nuclear Power Station and triggered an unprecedented core melt/severe accident in Units 1 – 3. The radioactivity release led to the evacuation of local residents, many of whom still have not been able to return to their homes. As a group of nuclear experts, the Atomic Energy Society of Japan established the Investigation Committee on the Nuclear Accident at the Fukushima Daiichi Nuclear Power Station, to investigate and analyze the accident from scientific and technical perspectives for clarifying the underlying and fundamental causes, and to make recommendations. The results of the investigation by the AESJ Investigation Committee has been compiled herewith as the Final Report. Direct contributing factors of the catastrophic nuclear incident at Fukushima Daiichi NPP initiated by an unprecedented massive earthquake/ tsunami – inadequacies in tsunami measures, severe accident ma...

  9. Scoping Study Investigating PWR Instrumentation during a Severe Accident Scenario

    Rempe, J. L. [Rempe and Associates, LLC, Idaho Falls, ID (United States); Knudson, D. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lutz, R. J. [Lutz Nuclear Safety Consultant, LLC, Asheville, NC (United States)

    2015-09-01

    The accidents at the Three Mile Island Unit 2 (TMI-2) and Fukushima Daiichi Units 1, 2, and 3 nuclear power plants demonstrate the critical importance of accurate, relevant, and timely information on the status of reactor systems during a severe accident. These events also highlight the critical importance of understanding and focusing on the key elements of system status information in an environment where operators may be overwhelmed with superfluous and sometimes conflicting data. While progress in these areas has been made since TMI-2, the events at Fukushima suggests that there may still be a potential need to ensure that critical plant information is available to plant operators. Recognizing the significant technical and economic challenges associated with plant modifications, it is important to focus on instrumentation that can address these information critical needs. As part of a program initiated by the Department of Energy, Office of Nuclear Energy (DOE-NE), a scoping effort was initiated to assess critical information needs identified for severe accident management and mitigation in commercial Light Water Reactors (LWRs), to quantify the environment instruments monitoring this data would have to survive, and to identify gaps where predicted environments exceed instrumentation qualification envelop (QE) limits. Results from the Pressurized Water Reactor (PWR) scoping evaluations are documented in this report. The PWR evaluations were limited in this scoping evaluation to quantifying the environmental conditions for an unmitigated Short-Term Station BlackOut (STSBO) sequence in one unit at the Surry nuclear power station. Results were obtained using the MELCOR models developed for the US Nuclear Regulatory Commission (NRC)-sponsored State of the Art Consequence Assessment (SOARCA) program project. Results from this scoping evaluation indicate that some instrumentation identified to provide critical information would be exposed to conditions that

  10. Scoping Study Investigating PWR Instrumentation during a Severe Accident Scenario

    The accidents at the Three Mile Island Unit 2 (TMI-2) and Fukushima Daiichi Units 1, 2, and 3 nuclear power plants demonstrate the critical importance of accurate, relevant, and timely information on the status of reactor systems during a severe accident. These events also highlight the critical importance of understanding and focusing on the key elements of system status information in an environment where operators may be overwhelmed with superfluous and sometimes conflicting data. While progress in these areas has been made since TMI-2, the events at Fukushima suggests that there may still be a potential need to ensure that critical plant information is available to plant operators. Recognizing the significant technical and economic challenges associated with plant modifications, it is important to focus on instrumentation that can address these information critical needs. As part of a program initiated by the Department of Energy, Office of Nuclear Energy (DOE-NE), a scoping effort was initiated to assess critical information needs identified for severe accident management and mitigation in commercial Light Water Reactors (LWRs), to quantify the environment instruments monitoring this data would have to survive, and to identify gaps where predicted environments exceed instrumentation qualification envelop (QE) limits. Results from the Pressurized Water Reactor (PWR) scoping evaluations are documented in this report. The PWR evaluations were limited in this scoping evaluation to quantifying the environmental conditions for an unmitigated Short-Term Station BlackOut (STSBO) sequence in one unit at the Surry nuclear power station. Results were obtained using the MELCOR models developed for the US Nuclear Regulatory Commission (NRC)-sponsored State of the Art Consequence Assessment (SOARCA) program project. Results from this scoping evaluation indicate that some instrumentation identified to provide critical information would be exposed to conditions that

  11. International cooperation and challenges: Understanding cross-cultural issues in the processes of accident investigation

    Li, Wen-Chin; Young, Hong-Tsu; Wang, Thomas; Harris, Don

    2007-01-01

    The idea that national cultural characteristics play a part in aviation safety had been suggested by Helmreich & Merritt (1998). This research involved around 45 aviation accident investigators from different cultural backgrounds and investigated attribution of causal factors in the Ueberlingen accident report through the application of the Human Factors Analysis and Classification System (Wiegmann & Shappell, 2003). Hofstede’s (1991 & 2001) cultural dimensions draw a clear picture of the att...

  12. The official report of the Fukushima Nuclear Accident Independent Investigation Commission

    In October 2011, the Act regarding Fukushima Nuclear Accident Independent Investigation Commission was enacted to investigate the Fukushima accident with the authority to request documents and request the legislative branch to use its investigative powers to obtain any necessary documents or evidence required. In December 2011, chairman and nine other members were appointed. After a six-month investigation, Commission had concluded. 'In order to prevent future disasters, fundamental reforms must take place covering both the structure of electric power industry and the structure of related government and regulatory agencies as well as operation processes, for both normal and emergency situations'. Main parts of report consisted of overview, conclusions and recommendations, and six findings; (1) was the accident preventable?, (2) Escalation of the accident, (3) Emergency response to the accident, (4) Spread of the damage, (5) Organizational issues in accident prevention and response and (6) the legal system. Based on the above findings, Commission made seven recommendations regarding (1) Monitoring of the nuclear regulatory body by the National Diet, (2) Reform the crisis management system, (3) Government responsibility for public health and welfare, (4) Monitoring the operators, (5) Criteria for the new regulatory body, (6) Reforming laws related to nuclear energy and (7) Develop a system of independent investigation commissions. National Diet's thorough debate and deliberate on these recommendation was highly encouraged for the future. (T. Tanaka)

  13. Accident investigation of the electrical shock incident at the PG and E PVUSA site Davis, California

    Jacobson, L.; Moskowitz, P.D.; Garrett, J.O.; Tyler, R.

    1992-02-01

    This report summarizes the findings of the Accident Investigation Team (Team) assembled in response to a request from Pacific Gas and Electric Company (PG and E) to the US Department of Energy (DOE) to understand the events surrounding the electric shock of a worker at the PVUSA site in Davis, California and to provide recommendations to prevent such events from recurring. The report gives complete details on the sequence of events surrounding the accident and identifies 27 facts related to accident itself. Four technical deficiencies in the electrical systems which require further investigation were identified. The Team believes that the root cause of this accident was related to the absence of a proactive organizational entity responsible for overall health and safety on the site. Two contributing factors were identified. First, the prototype nature and associated operational difficulties of the electrical inverter resulted in large maintenance demands. Second, several of the injured employee`s co-workers noted that he occasionally failed to use appropriate personal protective equipment, but they never reported this practice to management. The direct cause of this accident was the failure of the injured employee to wear appropriate personal protective equipment (i.e., rubber gloves). Based on the review of the facts established in this investigation, five recommendations are presented to the funding agencies to reduce the possibility of future accidents at the PVUSA site.

  14. Use of casual tree method for investigation of incidents and accidents involving radioactive materials

    There are many methodologies used for investigation of accidents to facilitate the search of the factors that cause these events in different areas of industry. These can be called proactive methods, if they are used before the occurrence of the events, or reactive methods that are applied after the occurrence of the incident or accident, and are used as a basis of information to prevent further events. One of these methods is the Causal Tree Method (CTM). The basic idea of this technique is that incidents and accidents result from variations in usual processes. These variations can be related to the individual, the task, the material or the environment. The tree starts with the end event (incident or accident) and works backwards. The facts relating to the end event are used in the construction of the causal tree. The end event is the starting point and only the facts that contributed to the incident or accident should be selected. The analyst has to identify and list the variations and then display them in the analytic tree, showing causal relations. The objective of this paper is to test the application of the CTM method in investigation of incidents and accidents involving radioactive materials, in order to evaluate its efficiency on finding the typical factors causing these events. (author)

  15. Review of five investigation committees' reports on the Fukushima Dai-ichi Nuclear Power Plant severe accident. Focusing on accident progression and causes

    On March 11, 2011, the Tohoku District-off the Pacific Ocean Earthquake and the subsequent tsunami resulted in the severe core damage at TEPCO's Fukushima Dai-ichi Nuclear Power Station Units 1-3, involving hydrogen explosions at Units 1, 3, and 4 and the large release of radioactive materials to the environment. Four independent committees were established by the Japanese government, the Diet of Japan, the Rebuild Japan Initiative Foundation, and TEPCO to investigate the accident and published their respective reports. Also, the Nuclear and Industrial Safety Agency carried out an analysis of accident causes to obtain the lessons learned from the accident and made its report public. This article reviews the reports and clarifies the differences in their positions, from the technological point of view, focusing on the accident progression and causes. Moreover, the undiscussed issues are identified to provide insights useful for the near-term regulatory activities including accident investigation by the Nuclear Regulation Authority. (author)

  16. Ontology Development and Evolution in the Accident Investigation Domain

    Carvalho, Robert; Berrios, Dan; Williams, James

    2004-01-01

    InvestiigationOrganizer (IO) is a collaborative semantic web system designed to support the conduct of mishap investigations. IO provides a common repository for a wide range of mishap related information, allowing investigators to integrate evidence, causal models, and investigation results. IO has been used to support investigations ranging from a small property damage case to the loss of the Space Shuttle Columbia. Through IO'S use in these investigations, we have learned significant lessons? about the application of ontologies and semantic systems to solving real-world problems. This paper will describe the development of the ontology within IO, from the initial development, its growth in response to user requests during use in investigations, and the recent work that was done to control the results of that growth. This paper will also describe the lessons learned from this experience and how they may apply to the implementaton of future ontologies and semantic systems.

  17. 32 CFR 634.30 - Use of traffic accident investigation report data.

    2010-07-01

    ... data will be used to inform and educate drivers and to conduct traffic engineering studies. (e) Army... 32 National Defense 4 2010-07-01 2010-07-01 true Use of traffic accident investigation report data... (CONTINUED) LAW ENFORCEMENT AND CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION Traffic...

  18. Review of the TMI-2 accident evaluation and vessel investigation projects

    The results of the TMI-2 Accident Evaluation Programme and the Vessel Investigation Project have been reviewed as part of a literature study on core meltdown and in-vessel coolability. The emphasis is placed on the late phase melt progression, which is of special relevance to the NKS-sponsored RAK-2.1 project on Severe Accident Phenomenology. The body of the report comprises three main sections, The TMI-2 Accident Scenario, Core Region and Relocation Path Investigations, and Lower Head Investigations. In the final discussion, the lower head gap formation mechanism is explained in terms of thermal contraction and fracturing of the debris crust. This model seems more plausible than the MAAP model based on creep expansion of the lower head. (au)

  19. Report of investigation regarding accident in Tomsk reprocessing facilities in Russia

    At 1258 on April 6, 1993, the explosion accident of a welded tank occurred in the military reprocessing facilities in Tomsk, Siberia District, Russia. Japan carried out the investigation of the effect on the environmental radiation in Japan, dispatched the investigation mission to Russia, and explained the way of thinking on securing the safety of Japanese reprocessing plants to local communities. Science and Technology Agency organized the working group for investigating the accident, which exerted efforts to collect the information, analyze and examine it. This report is the summary of its results. The explosion occurred in the tank for adjusting the acid concentration of the solution to be supplied to the solvent extraction shop, and the building was destructed. No one died or was injured. The results of the radioactivity examination are reported. The process of the accident was inferred, and described. The factors that caused the accident were the mixing of organic impurities the use of the diluting liquid containing aromatic hydrocarbon, the contact of nitric acid with organic substances at high temperature, in sufficient agitation at the time of pouring nitric acid and so on. The safety countermeasures in Japanese reprocessing plants and the response by Japan based on the accident are described. (K.I.)

  20. Study on Developments in Accident Investigation Methods: A Survey of the 'State-of-the-Art'

    The objective of this project was to survey the main accident investigation methods that have been developed since the early or mid-1990s. The motivation was the increasing frequency of accidents that defy explanations in simple terms, for instance cause-effect chains or 'human error'. Whereas the complexity of socio-technical systems is steadily growing across all industrial domains, including nuclear power production, accident investigation methods are only updated when their inability to account for novel types of accidents and incidents becomes inescapable. Accident investigation methods therefore typically lag behind the socio-technological developments by 20 years or more. The project first compiled a set of methods from the recognised scientific literature and in major major research and development programs, excluding methods limited to risk assessment, technological malfunctions, human reliability, and safety management methods. An initial set of 21 methods was further reduced to seven by retaining only prima facie accident investigation methods and avoiding overlapping or highly similar methods. The second step was to develop a set of criteria used to characterise the methods. The starting point was Perrow's description of normal accidents in socio-technical systems, which used the dimensions of coupling, going from loose to tight, and interactions, going from linear to complex. For practical reasons, the second dimension was changed to that of tractability or how easy it is to describe the system, where the sub-criteria are the level of detail, the availability of an articulated model, and the system dynamics. On this basis the seven selected methods were characterised in terms of the systems - or conditions - they could account for, leading to the following four groups: methods suitable for systems that are loosely coupled and tractable, methods suitable for systems that are tightly coupled and tractable, methods suitable for systems that are loosely

  1. Doses in radiation accidents investigated by chromosome aberration analysis

    Results from cytogenetic investigations into 55 cases of suspected over-exposure to radiation during 1977 are reviewed. This report is the seventh in an annual series (previous results were published in NRPB-R5, R10, R23, R35, R41 and R57) which together contain data on 327 studies. Results from all investigations have been pooled for general analysis. Brief accounts are given in an appendix of the circumstances behind the past year's investigations and, where possible, physical estimates of dose have been included for comparison. Two cases are described in more detail: the first concerned a non-classified worker who put an iridium-192 source in his pocket and took it home; and the second involved the accidental contamination of two people with tritium gas. In a second appendix, the confidence limits on cytogenetic dosimetry for X- and γ-ray over-exposures are given and the derivation of these limits is discussed. (author)

  2. Doses in radiation accidents investigated by chromosome aberration analysis

    The results are reviewed from investigations during 1979 into 82 cases of suspected over-exposure to radiation. Of these 45 were associated with industrial radiography, 11 with one or other of the major nuclear organisations, and 26 with an institution of research, education or health. 83% of the dose estimates were in the range 0.0-0.09 Gy (0-9 rad), and 17% in the range 0.1-0.29 Gy (10-29 rad). These data are compared with data obtained by physical dosimetry, and a brief summary is given of the circumstances of each over-exposure, or suspected over-exposure. (author)

  3. Doses in radiation accidents investigated by chromosome aberration analysis

    The results are reviewed from investigations during 1980 into 68 cases of suspected overexposure to radiation. Of these, 37 were associated with industrial radiography, 11 with one or other of the major nuclear organisations and 20 with an institution of research, education or health. 55 of the dose estimates were in the range 0.0 - 0.09 Gy (0 - 9 rad) 5 in the range 0.1 - 0.29 Gy (10 - 29 rad) and for various reasons in 8 cases no biological assessment of dose was possible. The dose estimate for the case with the highest confirmed overexposure was 0.22 Gy (22 rads). The chromosome data are compared with information obtained from physical dosimetry and a brief summary is given of the circumstances of each case. (author)

  4. Investigating the role of behavioral factors in non-fatal accidents of urban and suburban driver

    P. Azad

    2015-09-01

    Full Text Available Introduction: Road accidents are of the most important events, which cause death and injury of a large number of people and impose huge economic losses. According to previous studies, human factors are the main cause of traffic accidents. The purpose of this study was to investigate the role of behavioral factors in driving-related non-fatal accidents. Material and Method: The present analytical study was carried out among 150 drivers of urban and suburban transportation system in Yazd province. The research tool was Driver Behavior Questionnaire (DBQ which is consisted of two sections: demographic information and driving behavior. Result: 83/9 % of the participants reported to use safety belt nearly always. The highest deliberate violations, slips, and mistakes were belonged to drivers with age group of 18-25. Moreover, deliberate violations had a significant relationship with rage (P < 0.05. Survey of behavioral factors in terms of vehicle ownership type showed that “deliberate violations” and “slips and mistakes” high among personal bus drivers and state-owned bus drivers, respectively, which shows the significant association between these behavioral factors and ownership type. What is more, rates of deliberate and unintentional violations and slips were higher among those with a history of two times incidents (P < 0.004. Conclusion: The results revealed that behavioral factors such as age, type of vehicle ownership, and accident history played a significant role in occurrence of traffic accidents.

  5. Experimental investigations on vessel-hole ablation during severe accidents

    This report presents experimental results, and subsequent analyses, of scaled reactor pressure vessel (RPV) failure site ablation tests conducted at the Royal Institute of Technology, Division of Nuclear Power Safety (RIT/NPS). The goal of the test program is to reduce the uncertainty level associated with the phase-change-ablation process, and, thus, improve the characterization of the melt discharge loading on the containment. In a series of moderate temperature experiments, the corium melt is simulated by the binary oxide CaO-B2O3 or the binary eutectic and non-eutectic salts NaNO3-KNO3, while the RPV head steel is represented by a Pb, Sn or metal alloys plate. A complementary set of experiments was conducted at lower temperatures, using water as melt and salted ice as plate material. These experiments scale well to the postulated prototypical conditions. The multidimensional code HAMISA, developed at RIT/NPS, is employed to analyze the experiments with good pre- and post-test predictions. The effects of melt viscosity and crust surface roughness, along with failure site entrance and exit frictional losses on the ablation characteristics are investigated. Theoretical concept was proposed to describe physical mechanisms which govern the vessel-hole ablation process during core melt discharge from RPV. Experimental data obtained from hole ablation tests and separate-effect tests performed at RIT/NPS were used to validate component physical models of the HAMISA code. It is believed that the hole ablation phenomenology is quite well understood. Detailed description of experiments and experimental data, as well as results of analyses are provided in the appendixes

  6. Investigations of radioactivity level variations in Armenia after the Chernobyl accident

    The problem of radioactive pollution of biosphere has been acquiring a special topicality after nuclear weapon testing and NPP-induced accidents that have already brought to global pollution of the Earth with radioactive substances. One of visual examples of regional radioactive pollution is dispersion of emissions all over the territory of Central Europe after the Chernobyl accident, which aftermaths impacted Armenia, as well. Monitoring investigations in the Ararat Valley showed a precise peak of gross radioactivity of atmospheric fallout in 1986 - the year of Chernobyl accident. Gross mean annual radioactivity was established 1783 10 7 Bq/KXm 2 yr. Later, a sharp fall in the activity was observed. Mostly, radioactive fallout consisted of short-lived radionuclides. Measurements for 1986-1987 showed that gross β-radioactivity level in soils amounted to 977-1022 Bq/KXg, repeated measurements in 1991 allowed establishing 640-656 Bq/KXg. A precise indicator of radioactive emissions that reached Armenia after the Chernobyl accident was a short-lived radionuclide 134 Cs (T1/2=2.07 yr) identified in soils. Measurements made 2 years later showed half as much decay of 134 Cs, and in some points established were its traces only. 137 Cs/134 Cs ratio in varied 1.4 to 1.8 in atmospheric fallout and 2.1 to 33.4 in soils. Thus, monitoring investigations evidence a regional character of Chernobyl emission dispersion, this being proved by investigations of radioactivity level variations in Armenia, too

  7. Investigation of Radionuclide Concentrations in Pine Needles in Vietnam after the Chernobyl Accident

    This work presents the results of measurements concentrations in pine needles in Vietnam after the Chernobyl accident. Investigations were made since second half of 1986 to 1988. Increasing of concentration radionuclide levels in 1986 was not significant and was ended at the end of 1987. The concentrations of radionuclide Cs-137 in pine needles were compared with those in precipitations. The pine needles can be recommended as a useful and accessible material for supplementary monitoring of radioactive situation in the environment. The results obtained can contribute to the overall picture of studies on the dynamics of radioactive distribution and global fallouts formed by macro scale nuclear accidents. (author). 10 refs., 4 figs., 1 tab

  8. Preliminary Investigation of Candidate Materials for Use in Accident Resistant Fuel

    Jason M. Harp; Paul A. Lessing; Blair H. Park; Jakeob Maupin

    2013-09-01

    As part of a Collaborative Research and Development Agreement (CRADA) with industry, Idaho National Laboratory (INL) is investigating several options for accident resistant uranium compounds including silicides, and nitrides for use in future light water reactor (LWR) fuels. This work is part of a larger effort to create accident tolerant fuel forms where changes to the fuel pellets, cladding, and cladding treatment are considered. The goal fuel form should have a resistance to water corrosion comparable to UO2, have an equal to or larger thermal conductivity than uranium dioxide, a melting temperature that allows the material to stay solid under power reactor conditions, and a uranium loading that maintains or improves current LWR power densities. During the course of this research, fuel fabricated at INL will be characterized, irradiated at the INL Advanced Test Reactor, and examined after irradiation at INL facilities to help inform industrial partners on candidate technologies.

  9. Aircraft accident investigation: the decision-making in initial action scenario.

    Barreto, Marcia M; Ribeiro, Selma L O

    2012-01-01

    In the complex aeronautical environment, the efforts in terms of operational safety involve the adoption of proactive and reactive measures. The process of investigation begins right after the occurrence of the aeronautical accident, through the initial action. Thus, it is in the crisis scenario, that the person responsible for the initial action makes decisions and gathers the necessary information for the subsequent phases of the investigation process. Within this scenario, which is a natural environment, researches have shown the fragility of rational models of decision making. The theoretical perspective of naturalistic decision making constitutes a breakthrough in the understanding of decision problems demanded by real world. The proposal of this study was to verify if the initial action, after the occurrence of an accident, and the decision-making strategies, used by the investigators responsible for this activity, are characteristic of the naturalistic decision making theoretical approach. To attend the proposed objective a descriptive research was undertaken with a sample of professionals that work in this activity. The data collected through individual interviews were analyzed and the results demonstrated that the initial action environment, which includes restricted time, dynamic conditions, the presence of multiple actors, stress and insufficient information is characteristic of the naturalistic decision making. They also demonstrated that, when the investigators make their decisions, they use their experience and the mental simulation, intuition, improvisation, metaphors and analogues cases, as strategies, all of them related to the naturalistic approach of decision making, in order to satisfy the needs of the situation and reach the objectives of the initial action in the accident scenario. PMID:22317482

  10. Psychophysiological and other factors affecting human performance in accident prevention and investigation. [Comparison of aviation with other industries

    Klinestiver, L.R.

    1980-01-01

    Psychophysiological factors are not uncommon terms in the aviation incident/accident investigation sequence where human error is involved. It is highly suspect that the same psychophysiological factors may also exist in the industrial arena where operator personnel function; but, there is little evidence in literature indicating how management and subordinates cope with these factors to prevent or reduce accidents. It is apparent that human factors psychophysological training is quite evident in the aviation industry. However, while the industrial arena appears to analyze psychophysiological factors in accident investigations, there is little evidence that established training programs exist for supervisors and operator personnel.

  11. Status of ANL out-of-pile investigations of severe accident phenomena for liquid metal reactors

    Research addressing LMFBR whole core accidents has been terminated, and there is now emphasis on quantifying reactivity feedbacks, and in particular enhancing negative feedback, so that advanced LMR designs will provide inherently safe operation. The status of recent HCDA-related laboratory research performed at ANL, up to the time that such activities were no longer needed to support CRBR licensing, is described. Included are descriptions of programs addressing sodium channel voiding, fuel sweepout, fuel dispersal and plugging, boiled-up pool, UO2/sodium FCI, and debris coolability. Descriptions of recent investigations involving the metal fuel/sodium system are also included

  12. Status of ANL out-of-pile investigations of severe accident phenomena for liquid metal reactors

    Spencer, B.W.; Marchaterre, J.F.; Anderson, R.P.; Armstrong, D.R.; Baker, L.; Cho, D.H.; Gabor, J.D.; Pedersen, D.R.; Sienicki, J.J.; Stein, R.P.

    1986-01-01

    Research addressing LMFBR whole core accidents has been terminated, and there is now emphasis on quantifying reactivity feedbacks, and in particular enhancing negative feedback, so that advanced LMR designs will provide inherently safe operation. The status of recent HCDA-related laboratory research performed at ANL, up to the time that such activities were no longer needed to support CRBR licensing, is described. Included are descriptions of programs addressing sodium channel voiding, fuel sweepout, fuel dispersal and plugging, boiled-up pool, UO/sub 2//sodium FCI, and debris coolability. Descriptions of recent investigations involving the metal fuel/sodium system are also included.

  13. Aviation safety and maintenance under major organizational changes, investigating non-existing accidents.

    Herrera, Ivonne A; Nordskag, Arve O; Myhre, Grete; Halvorsen, Kåre

    2009-11-01

    The objective of this paper is to discuss the following questions: Do concurrent organizational changes have a direct impact on aviation maintenance and safety, if so, how can this be measured? These questions were part of the investigation carried out by the Accident Investigation Board, Norway (AIBN). The AIBN investigated whether Norwegian aviation safety had been affected due to major organizational changes between 2000 and 2004. The main concern was the reduction in safety margins and its consequences. This paper presents a summary of the techniques used and explains how they were applied in three airlines and by two offshore helicopter operators. The paper also discusses the development of safety related indicators in the aviation industry. In addition, there is a summary of the lessons learned and safety recommendations. The Norwegian Ministry of Transport has required all players in the aviation industry to follow up the findings and recommendations of the AIBN study. PMID:19819363

  14. Fukushima nuclear accident independent investigation commission by the National Diet of Japan

    After the Fukushima nuclear accident, Independent Investigation Commission (IIC) was firstly established in constitutional government by the National Diet of Japan. This article described recognition of its necessity, its setup process, its framework with start from almost zero and about 6 months period and time, its basic way to proceed investigation and several obstacles and hardships, significance of openness to the public, web's communication and simultaneous interpretation (transparency) and basic philosophy of the report. Further significance of Diet's IIC in the democratic system and evaluation of the report were added. As a problem of separation of three powers in Japan, specific recommendations to the legislation of IIC and their future evaluation, nation's governance system problem and social responsibility of scientists and others were also discussed. If Japan were not to be changed after the disaster, Japanese future might be unreliable. (T. Tanaka)

  15. Experimental investigation of thermal behavior of concentric tubes during a severe accident

    A pair of experiments were conceived and executed to provide data and a technical basis for investigating selected aspects of postulated severe accidents in a pressure tube/calandria tube configuration. The response to core damage and debris relocation within the pressure tube was investigated experimentally. The experimental objectives of the two tests were: 1) to assess the potential for failure of an unflawed pair of concentric tubes when prototypic wall stress is produced while high temperature debris is resident within the inner tube and sub-cooled water is present outside the outer tube, and 2) to assess the dynamic and energetic interaction given the rupture of the concentric tubes and the discharge of molten debris under steam pressure into the surrounding sub-cooled water pool. These experiments provide an effective demonstration of the passive cooling mechanism which can prevent calandria tube failure and of the interaction between molten debris and water if a calandria tube were to fail. (author)

  16. Test Plans for Investigating Molten Fuel Behavior in Coolant Channel during SFR Core Melting Accidents

    Suk, Soo Dong; Hahn, Doo Hee; Lee, Yong Bum

    2006-09-15

    The metal-fueled, sodium-cooled fast reactor system is expected to accommodate all credible malfunctions or accident initiators passively without damage to the core. However, the evaluation of the safety performance and the containment requirements for this system will most likely require consideration of postulated low-probability accident sequences that result in partial or whole core melting. For these sequences, some phenomenological uncertainties exist and experimental data are needed for modeling purposes. One such data need is concerned with the potential for freezing and plugging of molten metallic fuel in above-and below-core structures and possibly in inter subassembly spaces. The first basic data need is the properties for metallic fuel/steel mixtures such as liquidus/solidus and mobilization temperatures, as part of measurement of phenomenological data describing the relocation and freezing behavior of molten metallic fuel. Accordingly, plans for two different tests, one for determination of the liquidus/solidus temperature and another for determination of the mobilization temperature, are described in this report. Test plans are then described in the report for the investigations of the relocation and freezing behavior of molten metallic fuel in coolant channels, including possible chemical interactions of molten fuel with the channel steel structure.

  17. Test Plans for Investigating Molten Fuel Behavior in Coolant Channel during SFR Core Melting Accidents

    The metal-fueled, sodium-cooled fast reactor system is expected to accommodate all credible malfunctions or accident initiators passively without damage to the core. However, the evaluation of the safety performance and the containment requirements for this system will most likely require consideration of postulated low-probability accident sequences that result in partial or whole core melting. For these sequences, some phenomenological uncertainties exist and experimental data are needed for modeling purposes. One such data need is concerned with the potential for freezing and plugging of molten metallic fuel in above-and below-core structures and possibly in inter subassembly spaces. The first basic data need is the properties for metallic fuel/steel mixtures such as liquidus/solidus and mobilization temperatures, as part of measurement of phenomenological data describing the relocation and freezing behavior of molten metallic fuel. Accordingly, plans for two different tests, one for determination of the liquidus/solidus temperature and another for determination of the mobilization temperature, are described in this report. Test plans are then described in the report for the investigations of the relocation and freezing behavior of molten metallic fuel in coolant channels, including possible chemical interactions of molten fuel with the channel steel structure

  18. Discussion about Enterprise Accident Investigation and Analysis Methods%企业事故调查分析方法探讨

    孟凡强

    2011-01-01

    对企业事故调查分析方法进行了探讨,明确了企业事故调查分析程序,提出了具体的事故调查取证方法、事故原因分析方法和事故责任分析方法。%The investigation and analysis methods of enterprise accidents are discussed, the investigation and analysis procedure of enterprise accidents is defined and concrete accident investigating and evidence collecting methods, accident cause analysis methods and accident responsibility analysis methods are presented.

  19. An outline of the interim report of the investigation committee on the accident at Fukushima Nuclear Power Stations

    Interim report of the Investigation Committee of the Accident at Fukushima Nuclear Power Stations (NPSs) was published in December 26, 2011. The Japanese cabinet approved ten committee members including the author in May 2011. The committee interviewed more than 400 people over a total of 900 hours of hearings with about 40 staffs consisting of administrative team and three investigation teams of social system, root causes of the accident and countermeasures to prevent damage expansion of the accident. Interim report concluded 'the accident at Fukushima NPSs was caused by failures of every provision against reactor severe accident'. The failures appeared on (1) function of supervisory system for emergency response, (2) Fukushima Daiichi NPSs on-site disaster response especially related with operation of isolation condenser of unit 1 and high-pressure coolant injection system of unit 3, (3) Fukushima Daiichi NPSs off-site disaster response such the government failed to make use of data on the radioactive plumes released from the plant for evacuations, and (4) preparedness against tsunami and severe accident management. Possible worst or best simulation cases were also discussed. With no human support available on-site, workers might not have been able to prevent the meltdowns. Final report was due at the end of July 2012. (T. Tanaka)

  20. Investigation of relationship between mental workload and information flow rate of accident diagnosis tasks in NPPs

    The objective of this study is to investigate experimentally the relationship between an operator's mental workload and the information flow rate of accident diagnosis tasks and further to propose the information flow rate as an analytic method for measuring the mental workload. There are two types of mental workload in the advanced MCR of NPPs: the information processing workload, which is the processing that the human operator must actually perform in order to complete the diagnosis task, and emotional stress workload experienced by the operator. In this study, the focus is on the former. Three kinds of methods are used to measure the operator's workload: information flow rate, subjective methods, and physiological measures. Information flows for eight accident diagnosis tasks are modeled qualitatively using a stage model and are quantified using Conant's model. The eight accident cases are considered here are: Loss Of Coolant Accident (LOCA), Steam Generator Tube Rupture (SGTR), Steam Line Break (SLB), Feedwater Line Break (FLB), Pressurizer (PZR) spray and heater failure, Reactor Coolant Pump (RCP) trip, Main Steam Isolation Valve (MSIV) failure, and PZR spray failure. The information flow rate is obtained for each diagnosis task by imposing time limit restrictions for the tasks. Subjective methods require the operators to respond to questionnaires to rate their level of mental effort. NASA-TLX and MCH scale are selected as subjective methods. NASA-TLX is a subjective method used in the various fields including the aviation, automobile, and nuclear industries. It has a multi-dimensional rating technique and provides an overall workload score based on a weighted average on six subscales using pair-wise comparison tests. MCH, on the other hand, is one-dimensional and uses a 10- point rating technique. As with NASA-TLX, the higher the score is, the higher the subjective workload is. For the physiological measurements, an eye tracking system analyzes eye movements

  1. The crisis of investigative Journalism in Spain. The journalism practice in the Spanair accident

    José Vicente García-Santamaría, Ph.D.

    2010-01-01

    Full Text Available The crash of the McDonnell Douglas plane operated by the Spanish airline Spanair, on 20 August 2008 at Barajas Airport, and the journalistic treatment it received undoubtedly represent a unique opportunity to address the current state of journalism in Spain. In particular, this article studies the use of information sources in a crisis situation, which requires a major effort to find the maximum number of primary and specialised sources to provide, in a short period of time, the audience with the key facts to understand the event. This accident also represents an excellent opportunity to study some practices within investigative journalism and the different factors that condition the media agenda. Finally, as in any other air tragedy, where millionaire compensations can be paid to the victims, it is important to examine the application of a series of ethical frameworks, which have been captured in deontological codes designed to assure fair journalistic practices.

  2. Investigation of the radiological impact of reactor accidents under probabilistic aspects

    An analysis and conceptional investigation have been performed for the accident consequence model of the German reactor risk study. A dynamic atmospheric diffusion model is developed, which is applied in the first stage of the study to all distance ranges, and will be restricted finally to the long distance range. The wind direction and its variations are not taken into account in this model. The program set UFO-BAS calculates the time integrated nuclide concentration in air at any location downwind of the source. A further model which takes into account wind direction variations is being developed. On the basis of the proposals for the calculation of the health effects in the German risk study considerations on the storage requirements were accomplished. By means of these assessments a revised grid of parameters was evaluated. Furthermore, considerations were made for the implementation of an evaluation model, which will be developed by the Institut fuer Unfallforschung. (orig./RW)

  3. The investigation on the public panic caused from the Fukushima nuclear accident

    March 11, 2011, a huge earthquake and tidal waves in Japan lead to dangerous levels of nuclear leakage at Fukushima nuclear plant, the nuclear accident also cause public panic m many countries. To investigate the reason of the public panic, we employ the theories of sociology and psychology, analyzed that the public panic come from Ignorant Panic. Herd Behavior, Primacy Effect, Stereotype Activation Effect, and the superposition of these effects. In addition, we proposed three measures to the public panic: First, we should emphasize the safety of nuclear power and establish the positive image of nuclear power Second, we should emphasize the popular science of nuclear power so that nu clear power can be accepted in the public; Third, we should enhance the psychological intervention system for nuclear safe emergency and improve the effect of psychological intervention

  4. Study on Developments in Accident Investigation Methods: A Survey of the 'State-of-the-Art'

    Hollnagel, Erik; Speziali, Josephine (Ecole des Mines de Paris, F-06904 Sophia Antipolis (France))

    2008-01-15

    The objective of this project was to survey the main accident investigation methods that have been developed since the early or mid-1990s. The motivation was the increasing frequency of accidents that defy explanations in simple terms, for instance cause-effect chains or 'human error'. Whereas the complexity of socio-technical systems is steadily growing across all industrial domains, including nuclear power production, accident investigation methods are only updated when their inability to account for novel types of accidents and incidents becomes inescapable. Accident investigation methods therefore typically lag behind the socio-technological developments by 20 years or more. The project first compiled a set of methods from the recognised scientific literature and in major major research and development programs, excluding methods limited to risk assessment, technological malfunctions, human reliability, and safety management methods. An initial set of 21 methods was further reduced to seven by retaining only prima facie accident investigation methods and avoiding overlapping or highly similar methods. The second step was to develop a set of criteria used to characterise the methods. The starting point was Perrow's description of normal accidents in socio-technical systems, which used the dimensions of coupling, going from loose to tight, and interactions, going from linear to complex. For practical reasons, the second dimension was changed to that of tractability or how easy it is to describe the system, where the sub-criteria are the level of detail, the availability of an articulated model, and the system dynamics. On this basis the seven selected methods were characterised in terms of the systems - or conditions - they could account for, leading to the following four groups: methods suitable for systems that are loosely coupled and tractable, methods suitable for systems that are tightly coupled and tractable, methods suitable for systems that

  5. Investigation program on PWR-steel-containment behavior under accident conditions

    This report is a first documentation of the KfK/PNS activities and plans to investigate the behaviour of steel containments under accident conditions. The investigations will deal with a free standing spherical containment shell built for the latest type of a German pressurized water reactor. The diameter of the containment shell is 56 m. The minimum wall thickness is 38 mm. The material used is the ferritic steel 15MnNi63. According to the actual planning the program is concerned with four different problems which are beyond the common design and licensing practice: Containment behavior under quasi-static pressure increase up to containment failure. Containment behavior under high transient pressures. Containment oscillations due to earthquake loadings; consideration of shell imperfections. Containment buckling due to earthquake loadings. The investigation program consists of both theoretical and experimental activities including membrane tests allowing for very high plastic strains and oscillation tests with a thin-walled, high-accurate spherical shell. (orig.)

  6. Investigating Prevalence of deaths from Traffic Accidents and Factors Associated with it in Yazd in 2009

    Gh Soltani

    2014-02-01

    Conclusion: This study findings provide useful information for setting priorities in order to prevent the traffic accidents injuries. In addition, appropriate intervention programs are necessary in order to prevent traffic accidents and their complications, as well as to minimize injuries in accordance with other relevant organizations.

  7. The Role of Materials Degradation and Analysis in the Space Shuttle Columbia Accident Investigation

    McDanels, Steven J.

    2006-01-01

    The efforts following the loss of the Space Shuttle Columbia included debris recovery, reconstruction, and analysis. The debris was subjected to myriad quantitative and semiquantitative chemical analysis techniques, ranging from examination via the scanning electron microscope (SEM) with energy dispersive spectrometer (EDS) to X-Ray diffraction (XRD) and electron probe micro-analysis (EPMA). The results from the work with the debris helped the investigators determine the location where a breach likely occurred in the leading edge of the left wing during lift off of the Orbiter from the Kennedy Space Center. Likewise, the information evidenced by the debris was also crucial in ascertaining the path of impinging plasma flow once it had breached the wing. After the Columbia Accident Investigation Board (CAIB) issued its findings, the major portion of the investigation was concluded. However, additional work remained to be done on many pieces of debris from portions of the Orbiter which were not directly related to the initial impact during ascent. This subsequent work was not only performed in the laboratory, but was also performed with portable equipment, including examination via portable X-Ray fluorescence (XRF) and Fourier transform infrared spectroscopy (FTIR). Likewise, acetate and silicon-rubber replicas of various fracture surfaces were obtained for later macroscopic and fractographic examination. This paper will detail the efforts and findings from the initial investigation, as well as present results obtained by the later examination and analysis of debris from the Orbiter including its windows, bulkhead structures, and other components which had not been examined during the primary investigation.

  8. The investigation on the mass media reports on the JCO accident in the major atomic energy countries and Asian countries

    The JCO (Japan Conversion Organization) accident is the worst one in the history of the atomic energy developments in Japan. The many reports about the accident appeared in the 44 mass media in the world from Sep. 30 to Oct. 14, 1999. Chronological statistics of issued 522 articles are listed under particular criteria. Some of them were based on wrong knowledge and/or overestimations about the accident based on delivered articles by the news agency. Some of others gave critics over the total atomic energy industries of Japan, especially on safety managements and so-called similar Japan syndromes. This investigation gives emphasis on the articles based on wrong knowledge. We identified the countries and the newspaper publishers and the news agencies those gave wrong descriptions. Total 25 articles used the words [explosion] and [fire], which were delivered from the Kyodo News Service. Some of the Asian newspaper wrote that a large quantity of radioactivity, radioactive material and/or nuclear fuels was released. Some other news publishers said the accident was happened at fuel reprocessing facilities, when the waste fuel rods were under cutting. Critics delivered in the individual countries were summarized, i.e. USA, Canada, France, UK, German, Russia, Australia, China, Korea, Thailand, Vietnam, Indonesia, Taiwan and the news agencies. One of the key issues is the exact information release for the press corps on the early stage of the accidents. The second point is to recognize the different status on atomic energy in the individual countries, when Japan want to explain their domestic situations. Accidents of atomic energy gave many impacts on various aspects to other countries. Japan should understand the neighborhood by collecting world information on atomic energy and analyzing them. Summaries of 522 articles appeared in the mass media were attached in this investigation among the report of 180 pages. (Tanaka, Y.)

  9. Safety-critical human factors issues derived from analysis of the TEPCO Fukushima Daiichi accident investigation reports

    The Fukushima Daiichi nuclear power plant accident on March 11, 2011 had a large impact both in and outside Japan, and is not yet concluded. After Tokyo Electric Power Co.'s (TEPCO's) Fukushima accident, electric power suppliers have taken measures to respond in the event that the same state of emergency occurs - deploying mobile generators, temporary pumps and hoses, and training employees in the use of this equipment. However, it is not only the 'hard' problems including the design of equipment, but the 'soft' problems such as organization and safety culture that have been highlighted as key contributors in this accident. Although a number of organizations have undertaken factor analysis of the accident and proposed issues to be reviewed and measures to be taken, a systematic overview about electric power suppliers' organization and safety culture has not yet been undertaken. This study is based on three major reports: the report by the national Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission (the Diet report), the report by the Investigation Committee on the Accident at Fukushima Nuclear Power Stations of Tokyo Electric Power Company (Government report), and the report by the non-government committee supported by the Rebuild Japan Initiative Foundation (Non-government report). From these reports, the sections relevant to electric power suppliers' organization and safety culture were extracted. These sections were arranged to correspond with the prerequisites for the ideal organization, and 30 issues to be reviewed by electric power suppliers were extracted using brainstorming methods. It is expected that the identified issues will become a reference for every organization concerned to work on preventive measures hereafter. (author)

  10. Safety-critical human factors issues derived from analysis of the TEPCO Fukushima Daiichi accident investigation reports

    The Fukushima Daiichi nuclear power plant accident on March 11, 2011 had a large impact both in and outside Japan, and is not yet concluded. After Tokyo Electric Power Co.'s (TEPCO's) Fukushima accident, electric power suppliers have taken measures to respond in the event that the same state of emergency occurs - deploying mobile generators, temporary pumps and hoses, and training employees in the use of this equipment. However, it is not only the “hard” problems including the design of equipment, but the “soft” problems such as organization and safety culture that have been highlighted as key contributors in this accident. Although a number of organizations have undertaken factor analysis of the accident and proposed issues to be reviewed and measures to be taken, a systematic overview about electric power suppliers' organization and safety culture has not yet been undertaken. This study is based on three major reports: the report by the national Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission (the Diet report), the report by the Investigation Committee on the Accident at Fukushima Nuclear Power Stations of Tokyo Electric Power Company (Government report), and the report by the non-government committee supported by the Rebuild Japan Initiative Foundation (Non-government report). From these reports, the sections relevant to electric power suppliers' organization and safety culture were extracted. These sections were arranged to correspond with the prerequisites for the ideal organization, and 30 issues to be reviewed by electric power suppliers were extracted using brainstorming methods. It is expected that the identified issues will become a reference for every organization concerned to work on preventive measures hereafter. (author)

  11. Investigation of the different scenarios occurring in a PWR in case of a TMLB accident

    Severe accidents in light water reactors fall into one of two main categories, depending on whether or not core meltdown is accompanied by a pressure buildup in the primary system. The way in which the accident develops is, in fact, largely conditioned by this pressure aspect: temperature distribution in the core and primary system resulting from natural convection gas streams; fuel clad failure mode, etc... One major effect of pressure buildup on the accident scenario is primary system failure under the combined actions of pressure and temperature. The purpose of the present paper is to present, after a detailed thermalhydraulic study, an analysis of the timing and location of the system failures in case of a TMLB accident on CPY french type reactor

  12. Investigation on droplet impingement erosion during steam generator tube failure accident

    Highlights: ► Sodium droplet impingement is regarded as one of the mechanisms causing secondary tube failure in case of steam generator tube rupture accident. ► The moving particle semi-implicit (MPS) method is applied to simulate the sodium droplet impingement. ► The erosion rate correlation for water impingement is extended for application in the sodium impingement. - Abstract: Droplet impingement erosion is one of the reasons causing the secondary heat transfer tube damage in case of the heat transfer tube failure in the steam generator of sodium-cooled fast reactor. This paper has been dedicated to investigate the impingement phenomena, pressure load and the damage rate by impingement. Single droplet impingement on the rigid wall was first simulated with MPS-AS (moving particle semi-implicit method for all speeds) method for water and sodium. The shockwave propagation during the impingement has been well captured. The pressure load by water impingement can be characterized with . A correlation for pressure load by sodium impingement is proposed based on the water hammer theory. The new correlation shows to be consistent with the simulation result. For prediction of erosion rate by sodium droplet impingement, were extended by including the effects of liquid properties, i.e. density, sound speed and viscosity. The extended correlations show similar prediction accuracy to the original ones.

  13. Investigations related to the chemical behaviour of methyl iodide at severe PWR-accidents

    The decomposition velocity of methyl iodide in aqueous solutions of boric acid has been measured at temperatures up to 423 K and at chemical conditions which are expected to exist in the sumpwater pool during a severe reactor accident. The decomposition was due only to hydrolysis which increased by the expected amount at high temperature. No influence of the cooling water additives was observed. Treatment of the available kinetic data indicated that the influence of polluting material expectedly present in the sump is likely to be negligible too. A possible exception may be the enhancement of the decomposition rate by particulate and dissolved silver. The resistance of methyl iodide to gas phase decomposition by steam and oxygen at 423 K was investigated and only slow decomposition in the order of 10-7/s observed which is explained by reaction with steel surfaces. Neither gas phase oxidation nor hydrolysis occur at this temperature. The resistance to oxidation is of kinetic nature. Gas phase hydrolysis is not possible due to thermodynamics. This was confirmed by the observed gas phase formation of methyl iodide from hydrogen iodide and methanol at 423 K. The kinetics of this reaction are best explained by two parallel reactions, one of second order with a kinetic constant of 1.25 x 10-5/kPa s, and one of third order under action of steam with a constant of 2 x 10-6/kPa2 s. (orig./HP)

  14. An investigation of core liquid level depression in small break loss-of-coolant accidents

    Core liquid level depression can result in partial core dryout and heatup early in a small break loss-of-coolant accident (SBLOCA) transient. Such behavior occurs when steam, trapped in the upper regions of the reactor primary system (between the loop seal and the core inventory), moves coolant out of the core region and uncovers the rod upper elevations. The net result is core liquid level depression. Core liquid level depression and subsequent core heatups are investigated using subscale data from the ROSA-IV Program's 1/48-scale Large Scale Test Facility (LSTF) and the 1/1705-scale Semiscale facility. Both facilities are Westinghouse-type, four-loop, pressurized water reactor simulators. The depression phenomena and factors which influence the minimum core level are described and illustrated using examples from the data. Analyses of the subject experiments, conducted using the TRAC-PF1/MOD1 (Version 12.7) thermal-hydraulic code, are also described and summarized. Finally, the response of a typical Westinghouse four-loop plant (RESAR-3S) was calculated to qualitatively study coal liquid level depression in a full-scale system. 31 refs., 37 figs., 6 tabs

  15. ERSEC, investigation of the reflooding phase of a Loss of Coolant Accident

    1 - Description of test facility: ERSEC loop in Grenoble, France: - uniformly heated and internally cooled single tube installed in the ERSEC; - tube placed in a vacuum chamber with reflecting shield to reduce external heat losses; - constant operating conditions (flooding rate, subcooling of water and power generation); - initial conditions: Pressure 0.3 MPa; Flooding rate 52 kg/m2 s; inlet water subcooling 23 K; Power 6.2 KW. 2 - Description of test: Investigation of the thermal-hydraulics of the reflood phase of a loss of coolant accident. Scaling Information: - analytical experiment, two-phase thermal-hydraulic oriented exercise; - 0.3 MPa total pressure, assumed as constant. Parameters offered for Comparison: - wall temperatures of tube at 4 distinct elevations versus time; - quench time at different elevations; - water entrainment at tube exit versus time; - steam temperature at tube exit versus time. Findings: - experiment characterized by strong non-equilibrium effects(e.g. subcooled boiling and void formation); - thermal equilibrium codes could not predict the measurements in all respects; - RELAP4-MOD 6 empiricism derived from bundle experiments not applicable for this internally cooled mono-tube experiment; - ISP 7 results not representative for capabilities to predict nuclear plant system behaviour

  16. Experimental investigation of symmetric and asymmetric heating of pressure tube under accident conditions for Indian PHWR

    Yadav, Ashwini K., E-mail: ashwinikumaryadav@gmail.com [Department of Mechanical and Industrial Engineering, Indian Institute of Technology, Roorkee-247667 (India); Majumdar, P., E-mail: pmajum@barc.gov.in [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai-400085 (India); Kumar, Ravi, E-mail: ravikfme@iitr.ernet.in [Department of Mechanical and Industrial Engineering, Indian Institute of Technology, Roorkee-247667 (India); Chatterjee, B., E-mail: barun@barc.gov.in [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai-400085 (India); Gupta, Akhilesh, E-mail: akhilfme@iitr.ernet.in [Department of Mechanical and Industrial Engineering, Indian Institute of Technology, Roorkee-247667 (India); Lele, H.G., E-mail: hglele@barc.gov.in [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Circumferential temperature gradient for asymmetric heat-up was 400 Degree-Sign C. Black-Right-Pointing-Pointer At same pressure ballooning initiates at lower temperature in asymmetrical heat-up. Black-Right-Pointing-Pointer At 1 MPa ballooning initiated at 408 Degree-Sign C and with expansion rate of 0.005 mm/s. Black-Right-Pointing-Pointer At 2 MPa ballooning initiation at 330 Degree-Sign C and with expansion rate of 0.0056 mm/s. Black-Right-Pointing-Pointer For symmetrical heat-up strain rate was 10 times faster than asymmetric heat-up. - Abstract: In pressurized heavy water reactor (PHWR), under postulated scenario of small break Loss of Coolant Accident (LOCA) coincident with the failure of Emergency Core Cooling System (ECCS), a situation may arise under which reduction in mass flow rate of coolant through individual reactor channel can lead to stratified flow. Such stratified flow condition creates partial uncover of fuel bundle, which creates a circumferential temperature gradient over PT. The present investigation has been carried out to study thermo-mechanical behaviour of PT under asymmetric heating conditions for a 220 MWe PHWR. A 19-pin fuel simulator has been developed in which preferential heating of elements could be done by supplying power to the selected pins. The asymmetric heating of PT has been carried out at pressure 2 MPa and 1 MPa, respectively, by supplying power to upper region heating elements thus creating an half filled stratified flow conditions. The temperature difference up to 425 Degree-Sign C has been observed along top to bottom periphery of PT. A comparison is made between thermo-mechanical behaviour of PT under asymmetrical and symmetrical heat-up, expected from a large break LOCA condition. The radial expansion rate during symmetrical heating is found to be much faster as compared to that for asymmetric ballooning of PT at the same internal pressure. Integrity of PT is found to be

  17. Experimental investigation of symmetric and asymmetric heating of pressure tube under accident conditions for Indian PHWR

    Highlights: ► Circumferential temperature gradient for asymmetric heat-up was 400 °C. ► At same pressure ballooning initiates at lower temperature in asymmetrical heat-up. ► At 1 MPa ballooning initiated at 408 °C and with expansion rate of 0.005 mm/s. ► At 2 MPa ballooning initiation at 330 °C and with expansion rate of 0.0056 mm/s. ► For symmetrical heat-up strain rate was 10 times faster than asymmetric heat-up. - Abstract: In pressurized heavy water reactor (PHWR), under postulated scenario of small break Loss of Coolant Accident (LOCA) coincident with the failure of Emergency Core Cooling System (ECCS), a situation may arise under which reduction in mass flow rate of coolant through individual reactor channel can lead to stratified flow. Such stratified flow condition creates partial uncover of fuel bundle, which creates a circumferential temperature gradient over PT. The present investigation has been carried out to study thermo-mechanical behaviour of PT under asymmetric heating conditions for a 220 MWe PHWR. A 19-pin fuel simulator has been developed in which preferential heating of elements could be done by supplying power to the selected pins. The asymmetric heating of PT has been carried out at pressure 2 MPa and 1 MPa, respectively, by supplying power to upper region heating elements thus creating an half filled stratified flow conditions. The temperature difference up to 425 °C has been observed along top to bottom periphery of PT. A comparison is made between thermo-mechanical behaviour of PT under asymmetrical and symmetrical heat-up, expected from a large break LOCA condition. The radial expansion rate during symmetrical heating is found to be much faster as compared to that for asymmetric ballooning of PT at the same internal pressure. Integrity of PT is found to be maintained under both loading conditions. Heat sink around of test section, simulating moderator is found to be helpful in arresting the rise in temperature for both fuel

  18. Investigation into the March 28, 1979 Three Mile Island accident by Office of Inspection and Enforcement (Investigative Report No. 50-320/79-10)

    On March 28, 1979, the Three Mile Island Unit 2 Nuclear Power Plant experienced the most severe accident in U.S. commercial nuclear power plant operating history. This report sets forth the facts concerning the events of the accident determined as a result of an investigation by the NRC Office of Inspection and Enforcement. The IE investigation is limited to two aspects of the accident: (1) Those related operational actions by the licensee during the period from before the initiating event until approximately 8:00 p.m., March 28, when primary coolant flow was re-established by starting a reactor coolant pump, and (2) Those steps taken by the licensee to control the release of radioactive material to the off-site environs, and to implement his emergency plan during the period from the initiation of the event to midnight, March 30. These investigation periods were selected because they include the licensee actions which most significantly affected the accident sequence and its results

  19. Investigation on Melt-Structure-Water Interactions (MSWI) during severe accidents

    This report is the final report for the work performed in 1998 in the research project Melt Structure Water Interactions (MSWI), under the auspices of the APRI Project, jointly funded by SKI, HSK, USNRC and the Swedish and Finnish power companies. The present report describes results of advanced analytical and experimental studies concerning melt-water-structure interactions during the course of a hypothetical severe core meltdown accident in a light water reactor (LWR). Emphasis has been placed on phenomena and properties which govern the fragmentation and breakup of melt jets and droplets, melt spreading and coolability, and thermal and mechanical loadings of a pressure vessel during melt-vessel interaction. Many of the investigations performed in support of this project have produced papers which have been published in the proceedings of technical meetings. A short summary of the results achieved in these papers is provided in this overview. Both experimental and analytical studies were performed to improve knowledge about phenomena of melt-structure-water interactions. We believe that significant technical advances have been achieved during the course of these studies. It was found that: the solidification has a strong effect on the drop deformation and breakup. Initially appearing at the drop surface and, later, thickening inwards, the solid crust layer dampens the instability waves on the drop surface and, therefore, hinders drop deformation and breakup. The drop thermal properties also affect the thermal behavior of the drop and, therefore, have impact on its deformation behavior. The jet fragmentation process is a function of many related phenomena. The fragmentation rate depends not only on the traditional parameters, e.g. the Weber number, but also on the melt physical properties, which change as the melt cools down from the liquidus to the solidus temperature. Additionally, the crust formed on the surface of the melt jet will also reduce the propensity

  20. Investigation on Melt-Structure-Water Interactions (MSWI) during severe accidents

    Sehgal, B.R.; Yang, Z.L.; Dinh, T.N.; Nourgaliev, R.R.; Bui, V.A.; Haraldsson, H.O.; Li, H.X.; Konovakhin, M.; Paladino, D.; Leung, W.H [Royal Inst. of Tech., Stockholm (Sweden). Div. of Nuclear Power Safety

    1999-08-01

    This report is the final report for the work performed in 1998 in the research project Melt Structure Water Interactions (MSWI), under the auspices of the APRI Project, jointly funded by SKI, HSK, USNRC and the Swedish and Finnish power companies. The present report describes results of advanced analytical and experimental studies concerning melt-water-structure interactions during the course of a hypothetical severe core meltdown accident in a light water reactor (LWR). Emphasis has been placed on phenomena and properties which govern the fragmentation and breakup of melt jets and droplets, melt spreading and coolability, and thermal and mechanical loadings of a pressure vessel during melt-vessel interaction. Many of the investigations performed in support of this project have produced papers which have been published in the proceedings of technical meetings. A short summary of the results achieved in these papers is provided in this overview. Both experimental and analytical studies were performed to improve knowledge about phenomena of melt-structure-water interactions. We believe that significant technical advances have been achieved during the course of these studies. It was found that: the solidification has a strong effect on the drop deformation and breakup. Initially appearing at the drop surface and, later, thickening inwards, the solid crust layer dampens the instability waves on the drop surface and, therefore, hinders drop deformation and breakup. The drop thermal properties also affect the thermal behavior of the drop and, therefore, have impact on its deformation behavior. The jet fragmentation process is a function of many related phenomena. The fragmentation rate depends not only on the traditional parameters, e.g. the Weber number, but also on the melt physical properties, which change as the melt cools down from the liquidus to the solidus temperature. Additionally, the crust formed on the surface of the melt jet will also reduce the propensity

  1. Experimental investigations of BWR pressure suppression pool behavior under loss of coolant accident conditions

    The experiments discussed in this paper look into different processes which may occur during a loss-of-coolant accident in the pressure suppression pool of a Boiling Water Reactor (BWR). These processes include: a) development of a thermal stratification, b) bubble dynamics and related water flow during continuous release of air and c) air blowdown and associated water slug phenomenon in the water pool. The experiments have been performed in the THAI test facility, which is a cylindrical vessel of 9.2 m height, 3.2 m diameter and with a gas volume of 60 m3. The variation in the investigated test parameters included, steam and air mass flux, initial water pool temperature, blowdown pressures, downcomer submergence, etc. A systematic variation of the test parameters allowed better understanding of the phenomena. Experiments discussed in this paper were performed with a vertical downcomer of 0.1 m diameter and 2 m submergence depth in the water pool. For the blowdown experiments, a separate interconnecting vessel of 1 m3 volume was used to inject air at pressures between 3 bar and 10 bar. A high speed camera (1000 fps) was installed to visualize the formation and propagation of air bubbles in the suppression pool and the resulting pool swelling phenomena. Customized instrumentation applied during the tests included grids of densely spaced thermocouples and of pressure transducers at various locations in order to capture the temperature distribution in the pool and the water slug induced pressure loadings, respectively. The present paper discusses the main outcome of the selected experiments. On the whole the experimental data may be very useful for code validation. (authors)

  2. Accidents - Chernobyl accident; Accidents - accident de Tchernobyl

    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.)

  3. The Columbia Accident Investigation and The NASA Glenn Ballistic Impact Laboratory Contributions Supporting NASA's Return to Flight

    Melis, Matthew E.

    2007-01-01

    On February 1, 2003, the Space Shuttle Columbia broke apart during reentry, resulting in loss of the vehicle and its seven crewmembers. For the next several months, an extensive investigation of the accident ensued involving a nationwide team of experts from NASA, industry, and academia, spanning dozens of technical disciplines. The Columbia Accident Investigation Board (CAIB), a group of experts assembled to conduct an investigation independent of NASA, concluded in August, 2003 that the most likely cause of the loss of Columbia and its crew was a breach in the left wing leading edge Reinforced Carbon-Carbon (RCC) thermal protection system initiated by the impact of thermal insulating foam that had separated from the orbiters external fuel tank 81 seconds into the mission's launch. During reentry, this breach allowed superheated air to penetrate behind the leading edge and erode the aluminum structure of left wing, which ultimately led to the breakup of the orbiter. The findings of the CAIB were supported by ballistic impact tests, which simulated the physics of External Tank Foam impact on the RCC wing leading edge material. These tests ranged from fundamental material characterization tests to full-scale Orbiter Wing Leading Edge tests. Following the accident investigation, NASA spent the next 18 months focused on returning the shuttle safely to flight. In order to fully evaluate all potential impact threats from the many debris sources on the Space Shuttle during ascent, NASA instituted a significant impact testing program. The results from these tests led to the validation of high-fidelity computer models, capable of predicting actual or potential Shuttle impact events, were used in the certification of STS-114, NASA s Return to Flight Mission, as safe to fly. This presentation will provide a look into the inner workings of the Space Shuttle and a behind the scenes perspective on the impact analysis and testing done for the Columbia Accident Investigation and

  4. Pathmorphological investigation of pulmonary infections complications in persons dying from acute radiation sickness after Chernobyl accident

    Lungs of 27 persons who participated in liquidation of Chernobyl accident and died from acute radiation sickness were studied histologically. Pulmonary infections were found, including invasion of viral, bacterial and fungal agents. Being depended on hematopoietic function the inflammatory reactions were areactive during postirradiation aplasia and became typical within the recovery beginning

  5. Airborne and deposited radioactivity from the Chernobyl accident. A review of investigations in Finland

    Paatero, J. (Finnish Meteorogical Inst., Helsinki (Finland)); Haemeri, K. (Helsinki Univ., Dept. of Physics (Finland)); Jaakkola, T. (Helsinki Univ., Lab. of Radiochemistry (Finland)); Jantunen, M. (National Public Health Inst., Kuopio (Finland)); Koivukoski, J. (Ministry of the Interior, Rescue Dept., Government (Finland)); Saxen, R. (STUK Radiation and Nuclear Safety Authority, Helsinki (Finland))

    2010-07-01

    The Chernobyl nuclear accident happened in the former Soviet Union on 26 April 1986. The accident destroyed one of the RBMK-1000 type reactors and released significant radioactive contamination into the environment. At first the emissions were transported north-westwards over Poland, the Baltic States, Finland, Sweden and Norway. During 27 April 1986 emissions were spreading to eastern-central Europe, southern Germany, Italy and Yugoslavia. Radioactivity mapping over Finland between 29 April and 16 May 1986 showed that the ground deposition in Finland covered southern and central parts of the country but had an irregular distribution. The highest (over 100 muR h-1 [1 muSv h-1]) contamination disclosed by the mapping was around the city of Uusikaupunki in western Finland and the city of Kotka in southeastern Finland. The Uusikaupunki region was an area of heavy fallout associated with the air mass that was located in the Chernobyl area at the time of the accident. The fallout pattern of reftractory nuclides, e.g. plutonium isotopes, had their spatial maximum in this region. Medical consequences in Finland were luckily mild, the most important symptoms being psychological ones. No increase in thyroid cancer or birth defect occurrence has been observed. The Chernobyl accident boosted the radioecological research which had already been calming down after the last atmospheric nuclear test in China in October 1980. Important new results concerning e.g. hot particles have been achieved. The most important effects of the accident in Finland were, however, the increase of public awareness of environmental issues in general and especially of nuclear energy. In Finland, the nuclear energy programme was halted until 2002 when the Parliament of Finland granted a licence to build the fifth nuclear reactor in Finland. (orig.)

  6. Type A Accident Investigation Board report on the January 17, 1996, electrical accident with injury in Technical Area 21 Tritium Science and Fabrication Facility Los Alamos National Laboratory. Final report

    An electrical accident was investigated in which a crafts person received serious injuries as a result of coming into contact with a 13.2 kilovolt (kV) electrical cable in the basement of Building 209 in Technical Area 21 (TA-21-209) in the Tritium Science and Fabrication Facility (TSFF) at Los Alamos National Laboratory (LANL). In conducting its investigation, the Accident Investigation Board used various analytical techniques, including events and causal factor analysis, barrier analysis, change analysis, fault tree analysis, materials analysis, and root cause analysis. The board inspected the accident site, reviewed events surrounding the accident, conducted extensive interviews and document reviews, and performed causation analyses to determine the factors that contributed to the accident, including any management system deficiencies. Relevant management systems and factors that could have contributed to the accident were evaluated in accordance with the guiding principles of safety management identified by the Secretary of Energy in an October 1994 letter to the Defense Nuclear Facilities Safety Board and subsequently to Congress

  7. Type A Accident Investigation Board report on the January 17, 1996, electrical accident with injury in Technical Area 21 Tritium Science and Fabrication Facility Los Alamos National Laboratory. Final report

    NONE

    1996-04-01

    An electrical accident was investigated in which a crafts person received serious injuries as a result of coming into contact with a 13.2 kilovolt (kV) electrical cable in the basement of Building 209 in Technical Area 21 (TA-21-209) in the Tritium Science and Fabrication Facility (TSFF) at Los Alamos National Laboratory (LANL). In conducting its investigation, the Accident Investigation Board used various analytical techniques, including events and causal factor analysis, barrier analysis, change analysis, fault tree analysis, materials analysis, and root cause analysis. The board inspected the accident site, reviewed events surrounding the accident, conducted extensive interviews and document reviews, and performed causation analyses to determine the factors that contributed to the accident, including any management system deficiencies. Relevant management systems and factors that could have contributed to the accident were evaluated in accordance with the guiding principles of safety management identified by the Secretary of Energy in an October 1994 letter to the Defense Nuclear Facilities Safety Board and subsequently to Congress.

  8. Investigation of Two-Wheeled Road Traffic Accidents using Explicit FE Techniques.

    McLundie, W. M.

    2007-01-01

    With the increase of road traffic accidents increasing due to motorised traffic in the developing world growing alongside the more traditional bicycles and light motorcycles there is good reason to re-examine the two-wheeler case. In addition, if you include the large congestion charge scheme now underway in London and similar projects being considered in other cities globally, there is an even stronger case. These schemes encourage commuters to get back onto two wheels but ...

  9. Statistical investigation on the relation between car accident and warm katabatic winds

    The possible relationship between warm katabatic winds and human health and behaviour is analyzed; notwithstanding popular belief which is very positive about it, the connection has not been previously analyzed with the proper methods. We use a statistical model to address this question and our data suggest that the effects of warm katabatic winds in the Po Valley (Italy) can indeed be detected in the increase of car accidents

  10. An Investigation of Spray Performance to Remove Gaseous Iodine- Approach to mitigate the consequences of severe accident

    New technological approaches need to be in place to address such concern which has significantly deteriorated public confidence in nuclear power. Such technological approach must be capable of systematically mitigate the consequence of severe nuclear accidents involving radioactivity release. An example of such approach is spray technology. In case of an accident involving radioactivity release to the environment, it may possible to deploy spray system to quickly respond to the released radioactivity and to minimize the impact of accidental releases on humans and the environment. During early phase of Fukushima nuclear accident mitigation process, water spray operations were carried out through fire trucks and military helicopters, but the primary concern of such operations was to cool down the reactor and to extinguish the fire and not to minimize the spread of radioactive materials. The aim of this research is to investigate spray technology for effective and efficient capturing of fission products released from leaked/damaged nuclear reactor to the environment. For this purpose, a systematic approach with in depth information about release phenomena and spray features will be required. Based on the information regarding release phenomena including types of materials and their amount and size, release locations, release conditions such as rates, velocities, temperature, etc., requirements for spray application is being developed including spray material types (foam, mist etc.), spray solution additives, flow rates, pressure, drop size, spray coverage area and spray duration, etc. Subsequently the efficiency and effectiveness of spray system to reduce the Dispersion of radioactivity in the environment during the course of severe accident can be characterized. This paper is a summary of our initial investigation for the use of spray technology to reduce the consequence of severe nuclear accident. An experimental investigation of iodine removal efficiency in a spray

  11. The investigation of Passive Accident Mitigation Scheme for advanced PWR NPP

    Highlights: • We put forward a new PAMS and analyze its operation characteristics under SBO. • We conduct comparative analysis between PAMS and Traditional Secondary Side PHRS. • The PAMS could cope with SBO accident and maintain the plant in safe conditions. • PAMS could decrease heat removal capacity of PHRS. • PAMS has advantage in reducing cooling rate and PCCT temperature rising amplitude. - Abstract: To enhance inherent safety features of nuclear power plant, the advanced pressurized water reactors implement a series of passive safety systems. This paper puts forward and designs a new Passive Accident Mitigation Scheme (PAMS) to remove residual heat, which consists of two parts: the first part is Passive Auxiliary Feedwater System (PAFS), and the other part is Passive Heat Removal System (PHRS). This paper takes the Westinghouse-designed Advanced Passive PWR (AP1000) as research object and analyzes the operation characteristics of PAMS to cope with the Station Blackout Accident (SBO) by using RELAP5 code. Moreover, the comparative analysis is also conducted between PAMS and Traditional Secondary Circuit PHRS to derive the advantages of PAMS. The results show that the designed scheme can remove core residual heat significantly and maintain the plant in safe conditions; the first part of PAMS would stop after 120 min and the second part has to come into use simultaneously; the low pressurizer (PZR) pressure signal would be generated 109 min later caused by coolant volume shrinkage, which would actuate the Passive Safety Injection System (PSIS) to recovery the water level of pressurizer; the flow instability phenomenon would occur and last 21 min after the PHRS start-up; according to the comparative analysis, the coolant average temperature gradient and the Passive Condensate Cooling Tank (PCCT) water temperature rising amplitude of PAMS are lower than those of Traditional Secondary Circuit PHRS

  12. Investigation of VVER 1000 Core Degradation During SBO Accident Scenario in Case of Pressurizer SV Stuck in Open Position

    This paper presents the work performed at the Institute for Nuclear Research and Nuclear Energy (INRNE) in the frame of the SARNET2 project. The performed work continues the effort in modelling reactor core behaviour during severe accidents such as station blackout (SBO) sequence for VVER 1000 reactors based on parametric study. The work is oriented on investigation of overheated reactor core behaviour in case of reflooding by high pressure injection system (HPIS) at different stages and gives the preliminary results for the ASTEC V2 validation as well as analytical validation of severe accident management guidance (SAMG) for VVER 1000 reactors. An SBO scenario for investigation of VVER 1000 reactor core behaviour has been used with the assumption of opening the pressurizer safety valve and staying in open position, which induces additionally small break LOCA. Based on the previously performed work at the INRNE for the same scenarios a proper time for initiation has been chosen a proper time for initiation of HPP injection. For selected scenario consequently has been performed calculations vary the value of selected parameters. It has been selected the following parameters: porosity (PORO), velocity of molten mixture when crossing a grid (VGRI), etc. It has been investigated the influence of spherical and elliptical ''bottom head and lower plenum'' modelling on core degradation progression. (author)

  13. Investigation on two-phase critical flow for loss-of-coolant accident of pressurized water reactor

    1996-01-01

    The previous investigations were mainly conducted under the condition of low pressure,however,the steam-water specific volume and the interphase evaporation rate in high pressure are much different from those in low pressure,Therefore,the new experimental and theoretical investigation are performed in Xi'an Jiaotong University.The investigation results could be directly applied to the analysis of loss-of -coolant accident for pressurized water reacor.The system transition characteristics of cold leg and hot leg break loss-of -coolant tests are described for convective circulation test loop.Two types of loss-of-coolant accident are identified for :hot leg” break,while three types for “cold leg”break and the effect parameters on the break geometries.Tests indicate that the mass flow rate with convergent-divergent nozzle reaches the maximum value among the different break sections at the same inlet fluid condition because the fluid separation does not occur.A wall surface cavity nucleation model is developed for prediction of the critical mass flow rate with water flowing in convergentdivergent nozzles.

  14. Investigations of the behaviour of coated fuel particles and spherical fuel elements at accident temperatures

    A post irradiation annealing test apparature was constructed for the measurement of fission gas release at temperatures similar to those to be reached in a HTR during a hypothetical accident. From examinations with existing apparatures up to temperatures of 18000C results were available about the load capacity of coated particles as well as knowledges about fission gas release and defect behaviour. These results were used to plan a series of annealing tests with spherical fuel elements up to 25000C. It could be shown that the (U,Th)O2-particles with high burn up will fail during maximum core heat up of a HTR only after some hours at temperatures above 24000C. (orig.)

  15. Investigation of alternative solutions for severe accident management in future reactors

    Since 1991, the CEA/DRN 'Innovations-Future Reactors' Program (IFRP) has been developed in order to elaborate, to evaluate and validate technical options which can be of interest for future reactors. The main objectives of this program are: to improve both the safety and cost of future nuclear power plants, to optimize the fuel cycle and the management of nuclear materials. The present paper is focused on the third R and D theme, i.e., on the 'Innovation-Severe Accident Research Program' (ISARP). This specific CEA long-term program is developed in addition to shorter-term studies conducted in collaboration with the CEA partners (EDF and FRAMATOME), more particularly, for the future European Pressurized Water Reactor (EPR). (J.P.N.)

  16. Investigation of the behaviour of packaged radioactive waste under fire accident conditions

    A study has been made of the behaviour of packaged intermediate level waste (ILW) when exposed to fire conditions so as to provide information to support safety cases for ILW transport and disposal. The temperatures used in the study were selected to exceed those that the waste might be subject to in fire accidents during the transport and handling of ILW. Four waste materials, immobilised in cement or in organic resin, with properties representative of a wide range of waste streams were included in the study. Tests were carried out on samples of both real waste materials and non-radioactive simulants, and also on full-scale (500 litre) drums of simulant wastes. The overall release fractions were low, even for external temperatures of up to 1000oC. Examination showed that the stainless steel drums were still in good condition and on sectioning, little damage to the matrix or decrease in its strength was evident. (author)

  17. Fuel-element simulator for investigating thermal-hydraulic accidents in water-water reactors

    A fuel-element simulator should provide the necessary environmental parameters (thermal flux, and temperature at the cladding surface) and satisfy the requirements of reliability and modeling an actual fuel element, according to a formulated research problem. A universal simulator design, which could be used in a wide range of research, does not exist up to now and it is hardly useful in general. In developing fuel-element simulators to study loss-of-coolant accidents in water-water reactors, the most important condition from the modeling point of view is that the overall heat capacity of the simulator should correspond to that of the fuel element. The overall heat capacity and the temperature distribution over the reactor cross section determine the reserve of accumulated energy, which cannot be modeled by simply increasing the supplied electrical power. Experiments showed the magnesium oxide, as compared to other materials, is the best model of uranium oxide due to the closeness of the heat transfer coefficient and the thermal conductivity of these materials. Moreover, MgO has a high coefficient of thermal expansion, close to that of stainless steel. The construction of fuel-element simulators often uses boron nitride powder, which is densified by one means or another. Boron nitride has the highest thermal conductivity (besides beryllium oxide), but it has a lower electrical conductivity than magnesium oxide. These materials simultaneously fulfill the function of electrically insulating the heating element from the cladding. The basic disadvantage of this design is that the simulator has no gas gap; however, this is compensated by its simplicity, reliability, and long lifetime. This article presents several test designs for analysis and solving problems characteristic of loss-of-coolant accidents. Test results from VVER-440 fuel rod simulators using 19-rod assemblies an presented

  18. Prevention and investigations of core degradation in case of beyond design accidents of the 2400 MWTH gas-cooled fast reactor

    The present paper deals with studies carried out to assess the ability of the core of the Gas Fast Reactor (GFR) to withstand beyond design accidents. The work presented here is aimed at simulating the behaviour of this core by using analytical models whose input parameters are calculated with the CATHARE2 code. Among possible severe accident initiators, the Unprotected Loss Of Coolant Accident (ULOCA of 3 Inches diameter) is investigated in detail in the paper with CATHARE2. Additionally, a simplified pessimistic assessment of the effect of a postulated power excursion that could result from the failure of prevention provisions is presented. (author)

  19. Investigation of Focusing Effect according to the Cooling Condition and Height of the Metallic layer in a Severe Accident

    Moon, Je-Young; Chung, Bum-Jin [Kyung Hee University, Yongin (Korea, Republic of)

    2015-05-15

    The Fukushima nuclear power plant accident has led to renewed research interests in severe accidents of nuclear power plants. In-Vessel Retention (IVR) of core melt is one of key severe accident management strategies adopted in nuclear power plant design. The metallic layer is heated from below by the radioactive decay heat generated at the oxide pool, and is cooled from above and side walls. During the IVR process, reactor vessel may be cooled externally (ERVC) and the heat fluxes to the side wall increase with larger temperature difference than above. This {sup F}ocusing effect{sup i}s varied by cooling condition of upper boundary and height of the metallic layer. A sulfuric acid–copper sulfate (H{sub 2}SO{sub 4} - CuSO{sub 4}) electroplating system was adopted as the mass transfer system. Numerical analysis using the commercial CFD program FLUENT 6.3 were carried out with the same material properties and cooling conditions to examine the variation of the cell. The experimental and numerical studies were performed to investigate the focusing effect according to cooling condition of upper boundary and the height in metallic layer. The height of the side wall was varied for three different cooling conditions: top only, side only, and both top and side. Mass transfer experiments, based on the analogy concept, were carried out in order to achieve high Rayleigh number. The experimental results agreed well with the Rayleigh-Benard convection correlations of Dropkin and Somerscales and Globe and Dropkin. The heat transfer on side wall cooling condition without top cooling is highest and was enhanced by decreasing the aspect ratio. The numerical results agreed well with the experimental results. Each cell pattern (cell size, cell direction, central location of cell) differed in the cooling condition. Therefore, it is difficult to predict the internal flow due to complexity of cell formation behavior.

  20. Accidents - Chernobyl accident

    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.)

  1. Main investigation results on the forest radioecology in the Kyshtym and Chernobyl accident zones

    As a result of the long-term studies of radionuclide migration in forest ecosystems in zones of radioactive contamination after the Kyshtym and Chernobyl accidents, the following trends were revealed: (1) High retention capacity of stand canopy with respect to radioactive fallout. This leads to high doses absorbed by apical and leaf meristems, β-radiation giving the main part of the dose; (2) Fast self-decontamination of crowns during the growth period and relatively slow decontamination in the phase of physiological rest, regardless of amount of atmospheric precipitation. The rate of crown decontamination determines the value and duration of radiation stress on woody plants; (3) Accumulation not less than 95% of the total radionuclide amount in the forest litter 1-2 years after the cessation of radioactive fallout; (4) Relatively slow migration of strontium and cesium radionuclides along the forest soil profile; (5) High capacity of the forest when serving as a biogeochemical barrier to the routes of horizontal and vertical radionuclide migration and export out of the zone of initial contamination, including migration into the river water; (6) Considerable difference between strontium and cesium when migrating in forest soils and in the soil-plant system; (7) Broad variations in transfer factors for uptake of cesium-137 from soil into forest plants depending on the plant species and soil type. The primary radiobiological effects connected with irradiation of organisms are considered and secondary disturbances due to changes of ecological bonds between the components of irradiated forest ecosystem are discussed

  2. Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - final report

    On May 14, 1997, at 7:53 p.m. (PDT), a chemical explosion occur-red in Tank A- 109 in Room 40 of the Plutonium Reclamation Facility (Facility) located in the 200 West Area of the Hanford Site, approximately 30 miles north of Richland, Washington. The inactive processing Facility is part of the Plutonium Finishing Plant (PFP). On May 16, 1997, Lloyd L. Piper, Deputy Manager, acting for John D. Wagoner, Manager, U.S. Department of Energy (DOE), Richland Operations Office (RL), formally established an Accident Investigation Board (Board) to investigate the explosion in accordance with DOE Order 225. 1, Accident Investigations. The Board commenced its investigation on May 15, 1997, completed the investigation on July 2, 1997, and submitted its findings to the RL Manager on July 26, 1997. The scope of the Board's investigation was to review and analyze the circumstances of the events that led to the explosion; to analyze facts and to determine the causes of the accident; and to develop conclusions and judgments of need that may help prevent a recurrence of the accident. The scope also included the application of lessons learned from similar accidents within DOE. In addition to this detailed report, a companion document has also been prepared that provides a concise summary of the facts and conclusions of this report, with an emphasis on management issues (DOE/RL-97-63)

  3. Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - final report

    Gerton, R.E.

    1997-07-25

    On May 14, 1997, at 7:53 p.m. (PDT), a chemical explosion occur-red in Tank A- 109 in Room 40 of the Plutonium Reclamation Facility (Facility) located in the 200 West Area of the Hanford Site, approximately 30 miles north of Richland, Washington. The inactive processing Facility is part of the Plutonium Finishing Plant (PFP). On May 16, 1997, Lloyd L. Piper, Deputy Manager, acting for John D. Wagoner, Manager, U.S. Department of Energy (DOE), Richland Operations Office (RL), formally established an Accident Investigation Board (Board) to investigate the explosion in accordance with DOE Order 225. 1, Accident Investigations. The Board commenced its investigation on May 15, 1997, completed the investigation on July 2, 1997, and submitted its findings to the RL Manager on July 26, 1997. The scope of the Board`s investigation was to review and analyze the circumstances of the events that led to the explosion; to analyze facts and to determine the causes of the accident; and to develop conclusions and judgments of need that may help prevent a recurrence of the accident. The scope also included the application of lessons learned from similar accidents within DOE. In addition to this detailed report, a companion document has also been prepared that provides a concise summary of the facts and conclusions of this report, with an emphasis on management issues (DOE/RL-97-63).

  4. Investigation of relation between operator's mental workload and information flow in accident diagnosis tasks of nuclear power plant

    In the main control room (MCR) of a nuclear power plant (NPP), there are lots of dynamic information sources for MCR operator's situation awareness. As the human-machine interface in MCR is advanced, operator's information acquisition, information gathering and decision-making is becoming an important part to maintain the effective and safe operation of NPPs. Diagnostic task in complex and huge systems like NPP is the most difficult and mental effort-demanding for operators. This research investigates the relation between operator's mental workload and information flow in accident diagnosis tasks. The amount of information flow is quantified, using information flow model and Conant's model, a kind of information theory. For the mental workload measure, eye blink rate, blink duration, fixation time, number of fixation, and gaze direction are measured during accident diagnosis tasks. Subjective methods such as NASA-Task Load Index (NASA-TLX) and Modified Cooper-Harper (MCH) method are also used in the experiment. It is shown that the operator's mental workload has significant relation to information flow of diagnosis task. It makes possible to predict the mental workload through the quantity of the information flow of a system

  5. Investigations of radiocaesium in the natural terrestrial environment in Norway following the Chernobyl accident

    Radioactive fallout from the Chernobyl accident affected parts of central Norway to a considerable extent, in particular the 134Cs + 137Cs deposition had a significant impact on the natural environment. When this became apparent, a comprehensive radioecological research programme was initiated in order to study the behaviour of radiocaesium in boreal and alpine ecosystems, with emphasis on food-chains leading to exposure of species used for human consumption, i.e., reindeer and freshwater fish. In this paper results from the terrestrial part of this research programme during the period 1986-1990 are presented. The work was mainly confined to the mountain areas of Dovre and Rondane. Parallel studies were performed in eutrophic and strongly oligotrophic communities. The influence of local variations in topography and microclimate on the observed radiocaesium levels in topsoils, lichens and vascular plants was studied in detail. Currently a significant re-distribution of radiocaesium from the originally strongly exposed surfaces to those that were less exposed is observed. In the soil, radiocaesium is strongly retained in the litter and raw humus layers. Current levels in lichens are 1-2 orders of magnitude higher than in vascular plants. This strongly affects the seasonal variation of radiocaesium in reindeer, showing winter maxima of about 5 times higher than the August levels. The radiocaesium levels in reindeer showed a decline of approximately a factor of 3 during the period 1987-1990. Other animal species studied in the programme exhibited substantially lower radiocaesium levels than reindeer, but a considerable interspecies variation was observed. (author)

  6. Cyclical Fluctuations in Workplace Accidents

    Boone, J.; van Ours, J.C.

    2002-01-01

    This Paper presents a theory and an empirical investigation on cyclical fluctuations in workplace accidents. The theory is based on the idea that reporting an accident dents the reputation of a worker and raises the probability that he is fired. Therefore a country with a high or an increasing unemployment rate has a low (reported) workplace accident rate. The empirical investigation concerns workplace accidents in OECD countries. The analysis confirms that workplace accident rates are invers...

  7. Investigation of fragmentation phenomena and debris bed formation during core meltdown accident in SFR using simulated experiments

    Highlights: • Study on settling characteristics of debris after severe accident in SFR. • Understanding fragmentation mechanisms of liquid molten simulant. • Correlation between key parameters of PSD in the ULLN expression. • Investigation of debris bed formation and radial stratification on collector tray. - Abstract: The event of a severe core melt down accident, resulting in the relocation of the active core is analyzed as a part of the nuclear reactor safety research in order to ensure safe removal of decay heat. Molten Fuel Coolant Interaction (MFCI) and debris bed configuration on the core catcher plate assumes importance in assessing the post accident heat removal capability. The key factors affecting the coolability of the debris bed are the bed porosity, morphology of the fragmented particles, degree of spreading/heaping of the debris on the core catcher and the fraction of lump formed. A well defined debris bed is helpful in fixing a prototypical source term for the PAHR studies. Towards this, a series of experiments on fragmentation kinetics and subsequent debris bed formation is conducted with molten Wood's metal (an alloy of Bi 50%, Pb 25%, Sn 12.5% and Cd 12.5% with melting point of 346 K) in water simulant system. The experiments are carried out using 2 kg, 5 kg and 20 kg melt inventories. The particle size distribution obtained for the fragmented debris is fit using an Upper Limit Log Normal (ULLN) distribution. The dependence of particle size distribution on initial melt temperature and interaction height is quantified by correlating them to the key parameters i.e. shape factor and location factor in the ULLN expression. Morphology of the debris particles is investigated to understand the fragmentation mechanisms involved. Three major mechanisms of fragmentation are identified namely melt entrainment mechanism, boundary layer stripping and hydrodynamic breakup due to capillary forces. Finally, an approach to quantify the stratification

  8. Investigation of fragmentation phenomena and debris bed formation during core meltdown accident in SFR using simulated experiments

    Mathai, Amala M., E-mail: amala@igcar.gov.in [Safety Engineering Division, RDG, IGCAR, Kalpakkam, Tamilnadu 603102 (India); Sharma, Anil Kumar, E-mail: aksharma@igcar.gov.in [Safety Engineering Division, RDG, IGCAR, Kalpakkam, Tamilnadu 603102 (India); Anandan, J., E-mail: janand@igcar.gov.in [Safety Engineering Division, RDG, IGCAR, Kalpakkam, Tamilnadu 603102 (India); Malarvizhi, B., E-mail: malar@igcar.gov.in [Safety Engineering Division, RDG, IGCAR, Kalpakkam, Tamilnadu 603102 (India); Das, Sanjay Kumar, E-mail: skd@igcar.gov.in [Safety Engineering Division, RDG, IGCAR, Kalpakkam, Tamilnadu 603102 (India); Nashine, B.K., E-mail: bknash@igcar.gov.in [Safety Engineering Division, RDG, IGCAR, Kalpakkam, Tamilnadu 603102 (India); Chellapandi, P., E-mail: pcp@igcar.gov.in [Reactor Design Group (RDG), IGCAR, Kalpakkam, Tamilnadu 603102 (India)

    2015-10-15

    Highlights: • Study on settling characteristics of debris after severe accident in SFR. • Understanding fragmentation mechanisms of liquid molten simulant. • Correlation between key parameters of PSD in the ULLN expression. • Investigation of debris bed formation and radial stratification on collector tray. - Abstract: The event of a severe core melt down accident, resulting in the relocation of the active core is analyzed as a part of the nuclear reactor safety research in order to ensure safe removal of decay heat. Molten Fuel Coolant Interaction (MFCI) and debris bed configuration on the core catcher plate assumes importance in assessing the post accident heat removal capability. The key factors affecting the coolability of the debris bed are the bed porosity, morphology of the fragmented particles, degree of spreading/heaping of the debris on the core catcher and the fraction of lump formed. A well defined debris bed is helpful in fixing a prototypical source term for the PAHR studies. Towards this, a series of experiments on fragmentation kinetics and subsequent debris bed formation is conducted with molten Wood's metal (an alloy of Bi 50%, Pb 25%, Sn 12.5% and Cd 12.5% with melting point of 346 K) in water simulant system. The experiments are carried out using 2 kg, 5 kg and 20 kg melt inventories. The particle size distribution obtained for the fragmented debris is fit using an Upper Limit Log Normal (ULLN) distribution. The dependence of particle size distribution on initial melt temperature and interaction height is quantified by correlating them to the key parameters i.e. shape factor and location factor in the ULLN expression. Morphology of the debris particles is investigated to understand the fragmentation mechanisms involved. Three major mechanisms of fragmentation are identified namely melt entrainment mechanism, boundary layer stripping and hydrodynamic breakup due to capillary forces. Finally, an approach to quantify the stratification

  9. Investigation of Countercurrent Helium-Air Flows in Air-ingress Accidents for VHTRs

    Sun, Xiaodong; Christensen, Richard; Oh, Chang

    2013-10-03

    The primary objective of this research is to develop an extensive experimental database for the air- ingress phenomenon for the validation of computational fluid dynamics (CFD) analyses. This research is intended to be a separate-effects experimental study. However, the project team will perform a careful scaling analysis prior to designing a scaled-down test facility in order to closely tie this research with the real application. As a reference design in this study, the team will use the 600 MWth gas turbine modular helium reactor (GT-MHR) developed by General Atomic. In the test matrix of the experiments, researchers will vary the temperature and pressure of the helium— along with break size, location, shape, and orientation—to simulate deferent scenarios and to identify potential mitigation strategies. Under support of the Department of Energy, a high-temperature helium test facility has been designed and is currently being constructed at Ohio State University, primarily for high- temperature compact heat exchanger testing for the VHTR program. Once the facility is in operation (expected April 2009), this study will utilize high-temperature helium up to 900°C and 3 MPa for loss-of-coolant accident (LOCA) depressurization and air-ingress experiments. The project team will first conduct a scaling study and then design an air-ingress test facility. The major parameter to be measured in the experiments is oxygen (or nitrogen) concentration history at various locations following a LOCA scenario. The team will use two measurement techniques: 1) oxygen (or similar type) sensors employed in the flow field, which will introduce some undesirable intrusiveness, disturbing the flow, and 2) a planar laser-induced fluorescence (PLIF) imaging technique, which has no physical intrusiveness to the flow but requires a transparent window or test section that the laser beam can penetrate. The team will construct two test facilities, one for high-temperature helium tests with

  10. Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - summary report

    This report is a summary of the Accident Investigation Board Report on the May 14, 1997, Chemical Explosion at the Plutonium Reclamation Facility, Hanford Site, Richland, Washington (DOE/RL-97-59). The referenced report provides a greater level of detail and includes a complete discussion of the facts identified, analysis of those facts, conclusions derived from the analysis, identification of the accident's causal factors, and recommendations that should be addressed through follow-up action by the U.S. Department of Energy and its contractors. This companion document provides a concise summary of that report, with emphasis on management issues. Evaluation of emergency and occupational health response to, and radiological and chemical releases from, this accident was not within the scope of this investigation, but is the subject of a separate investigation and report (see DOE/RL-97-62)

  11. A Look at Aircraft Accident Analysis in the Early Days: Do Early 20th Century Accident Investigation Techniques Have Any Lessons for Today?

    Holloway, C. M.; Johnson, C. W.

    2007-01-01

    In the early years of powered flight, the National Advisory Committee on Aeronautics in the United States produced three reports describing a method of analysis of aircraft accidents. The first report was published in 1928; the second, which was a revision of the first, was published in 1930; and the third, which was a revision and update of the second, was published in 1936. This paper describes the contents of these reports, and compares the method of analysis proposed therein to the methods used today.

  12. Medical Response, Search and Recovery during the Space Shuttle Columbia Accident Investigation

    Stepaniak, Philip C.

    2010-01-01

    On February 1, 2003, the Space Shuttle Columbia broke apart during atmospheric re-entry on mission STS-107. After an event such as this, with high visibility and international interest, the operational challenge of recovering the crewmembers could not be underestimated. The Space Shuttle Program is organized to respond to a vehicle mishap using the resources of the Mishap Investigation Team (MIT). On the afternoon of Feb. 1, 2003, the MIT deployed to Barksdale Air Force Base (AFB), Louisiana. This location became the investigative center and interim storage location for crewmembers received from the Lufkin, Texas Disaster Field Office (DFO). The Lufkin DFO served as the primary area for all operations, including staging assets and deploying field teams for search, recovery and security of crewmember remains. More than 2,000 people from numerous organizations were involved with the recovery of the crew. All seven crewmembers of STS-107 were recovered and ceremonial last rights were administered. Astronaut and military personnel escorted the crew with honor to the MIT at Barksdale AFB, Louisiana. At Barksdale AFB a temporary morgue was established in an aircraft hangar and operated for approximately two weeks during which time coordination with the DFO field recovery teams, Armed Forces Institute of Pathology (AFIP) medical personnel, and the crew surgeons was on going. Families of crewmembers and NASA management were notified daily of the current findings. Working under the leadership of the MIT Lead, the medical team developed and executed a short-term plan to identify and relocate the crew with a military honor guard and protocol to the medical examiner at the Armed Forces Port Mortuary, Dover AFB, Delaware. After operations at Barksdale AFB were concluded the medical team transitioned back to Houston and a long-term plan was developed and implemented which involved the Air Force Mortuary Affairs at Randolph AFB, Texas. This plan was coordinated with search teams

  13. Preliminary investigation on the primary heat exchanger lower head rupture accident of forced circulation LBE-cooled fast reactor

    Highlights: • A forced circulation LBE-cooled fast reactor was developed in China. • The steady state of this reactor was simulated by using NTC program. • The HXLHR accident of this reactor was simulated by using NTC program. • Some vapors were dragged into the core by LBE during the HXLHR accident. - Abstract: The problem about the interaction between heavy liquid metal and water is one of the grand challenges in the development of lead or Lead–Bismuth Eutectic (LBE) cooled fast reactor. In this paper, the primary heat exchanger lower head rupture (HXLHR) accident of a forced circulation LBE-cooled fast reactor was simulated with a transient analysis code NTC (Neutronics and Thermal–hydraulics Coupled transient analysis program). The simulation results showed that the water in primary heat exchanger was injected into the primary circuit and vaporized immediately. Then the main vessel was pressurized and the maximum pressure was about 27 bar compared with 0.5 bar in normal condition. During the accident, some of the generated vapors were dragged into the core by LBE, which may cause a reactivity insertion accident. If any positive void coefficient exists in the core, a further study on the HXLHR accident should be performed to evaluate the reactivity insertion accident

  14. Investigating Montara platform oil spill accident by implementing RST-OIL approach.

    Satriano, Valeria; Ciancia, Emanuele; Coviello, Irina; Di Polito, Carmine; Lacava, Teodosio; Pergola, Nicola; Tramutoli, Valerio

    2016-04-01

    Oil Spills represent one of the most harmful events to marine ecosystems and their timely detection is crucial for their mitigation and management. The potential of satellite data for their detection and monitoring has been largely investigated. Traditional satellite techniques usually identify oil spill presence applying a fixed threshold scheme only after the occurrence of an event, which make them not well suited for their prompt identification. The Robust Satellite Technique (RST) approach, in its oil spill detection version (RST-OIL), being based on the comparison of the latest satellite acquisition with its historical value, previously identified, allows the automatic and near real-time detection of events. Such a technique has been already successfully applied on data from different sources (AVHRR-Advanced Very High Resolution Radiometer and MODIS-Moderate Resolution Imaging Spectroradiometer) showing excellent performance in detecting oil spills both during day- and night-time conditions, with an high level of sensitivity (detection also of low intensity events) and reliability (no false alarm on scene). In this paper, RST-OIL has been implemented on MODIS thermal infrared data for the analysis of the Montara Platform (Timor Sea - Australia) oil spill disaster occurred in August 2009. Preliminary achievements are presented and discussed in this paper.

  15. Nondestructive Testing As a Tool in the Space Shuttle Columbia Accident Investigation

    McDanels, Steve

    2008-01-01

    Nondestructive testing (NDT) played a crucial role in determining the Columbia tragedy's cause. Over 84,000 pieces of debris were recovered; hundreds were subsequently subjected to NDT and materials analysis. Visual NDT of the debris revealed localized areas of damage such as erosion, excessive heating, knife edging and mechanical damage. Three-dimensional reconstructions were made of the left wing leading edge, utilizing a tripod-mounted laser scanning head and focused laser beam, and an advanced topometric optical scanner (ATOS) with digital white light to scan complex-shaped debris, producing monochrome 3-D models. Texture mapping provided a means to capture true colors of the debris and superimpose them on the scanned images. Uniform deposits were found over large portions of debris, obscuring underlying materials. To determine what was beneath, inverse radiography was enlisted. The radiographs guided investigators to where samples should be taken. To ascertain compositions, these samples were subjected to analytical testing, including energy dispersive X-ray spectroscopy and electron microprobe analysis. This combination of visual evidence, radiography, virtual reconstruction, and materials analysis allowed the forensic scientists to verify that a breach occurred in the leading edge of the left wing, the path the plasma followed, and the sequence of events that led to the loss.

  16. Important severe accident research issues after Fukushima accident

    After the Fukushima accident several investigation committees issued reports with lessons learned from the accident in Japan. Among those lessons, several recommendations have been made on severe accident research. Similar to the EURSAFE efforts under EU Program, review of specific severe accident research items was started before Fukushima accident in working group of Atomic Energy Society of Japan (AESJ) in terms of significance of consequences, uncertainties of phenomena and maturity of assessment methodology. Re-investigation has been started since the Fukushima accident. Additional effects of Fukushima accident, such as core degradation behaviors, sea water injection, containment failure/leakage and re-criticality have been covered. The review results are categorized in ten major fields; core degradation behavior, core melt coolability/retention in containment vessel, function of containment vessel, source term, hydrogen behavior, fuel-coolant interaction, molten core concrete interaction, direct containment heating, recriticality and instrumentation in severe accident conditions. Based on these activities and also author's personal view, the present paper describes the perspective of important severe accident research issues after Fukushima accident. Those are specifically investigation of damaged core and components, advanced severe accident analysis capabilities and associated experimental investigations, development of reliable passive cooling system for core/containment, analysis of hydrogen behavior and investigation of hydrogen measures, enhancement of removal function of radioactive materials of containment venting, advanced instrumentation for the diagnosis of severe accident and assessment of advanced containment design which excludes long-term evacuation in any severe accident situations. (author)

  17. Long-term investigations of radiocaesium activity concentrations in carp in North Croatia after the Chernobyl accident

    Long-term investigations of radiocaesium activity concentrations in carp in the Republic of Croatia are presented. The radiocaesium levels in carp decreased exponentially and the effective ecological half-life of 137Cs was estimated to be about 1 year during 1987-2002 and 5 years during 1993-2005. The observed 134Cs:137Cs activity ratio in carp was found to be similar to the ratio observed in other environmental samples. The concentration factor for carp (wet weight) was estimated to be 128 ± 74 L kg-1, which is in reasonable agreement with model prediction based on K+ concentrations in water. Estimated annual effective dose received by adult members of the Croatian population due to consumption of carp contaminated with 134Cs and 137Cs are small: per capita dose from this source during 1987-2005 was estimated to be 0.5 ± 0.2 μSv. Due to minor freshwater fish consumption in Croatia and low radiocaesium activity concentrations in carp, it can be concluded that carp consumption was not a critical pathway for the transfer of radiocaesium from fallout to humans after the Chernobyl accident

  18. Analysis methodology for RBMK-1500 core safety and investigations on corium coolability during a LWR severe accident

    This thesis presents the work involving two broad aspects within the field of nuclear reactor analysis and safety. These are: - development of a fully independent reactor dynamics and safety analysis methodology of the RBMK-1500 core transient accidents and - experiments on the enhancement of coolability of a particulate bed or a melt pool due to heat removal through the control rod guide tubes. The first part of the thesis focuses on the development of the RBMK-1500 analysis methodology based on the CORETRAN code package. The second part investigates the issue of coolability during severe accidents in LWR type reactors: the coolability of debris bed and melt pool for in-vessel and ex-vessel conditions. The first chapter briefly presents the status of developments in both the RBMK-1500 core analysis and the corium coolability areas. The second chapter describes the generation of the RBMK-1500 neutron cross section data library with the HELIOS code. The cross section library was developed for the whole range of the reactor conditions. The results of the benchmarking with the WIMS-D4 code and validation against the RBMK Critical Facility experiments is also presented here. The HELIOS generated neutron cross section data library provides a close agreement with the WIMS-D4 code results. The validation against the data from the Critical Experiments shows that the HELIOS generated neutron cross section library provides excellent predictions for the criticality, axial and radial power distribution, control rod reactivity worths and coolant reactivity effects, etc. The reactivity effects of voiding for the system, fuel assembly and additional absorber channel are underpredicted in the calculations using the HELIOS code generated neutron cross sections. The underprediction, however, is much less than that obtained when the WIMS-D4 code generated cross sections are employed. The third chapter describes the work, performed towards the accurate prediction, assessment and

  19. Investigations of the potential for accident mitigation of the conceptical design for a core retention device developed in SR 209

    The potential for accident mitigation of the conceptual design for the core retention device developed in SR 209, was estimated by core meltdown and containment analyses. Such a device should prevent late fission product release especially due to failure of the containment by overpressurization (according to release categories 5 and 6 of the German Risk Study, Phase A). Assuming ideal operation of the device, the long term course of a meltdown accident can be influenced in a positive sense including the prevention of overpressurization. However, functional operation of the design seems to be highly uncertain for several reasons, i.g. due to uncertainties in the behaviour of the melt in the retention device. The design does not or only insufficiently cover accident scenarios with high pressure in vessel melt, that means for sequences relevant for their high contribution to core melt frequency. The design may have strong negative impacts on the course of meltdown accidents, LOCA's, constructive details and operation of a plant. Implementation of the measure is expected to need extreme effort, without making sense from the technical point of view. The measure at all seems not to be recommendable for accident mitigation. (orig./HP)

  20. Internal Flow Thermal/Fluid Modeling of STS-107 Port Wing in Support of the Columbia Accident Investigation Board

    Sharp, John R.; Kittredge, Ken; Schunk, Richard G.

    2003-01-01

    As part of the aero-thermodynamics team supporting the Columbia Accident Investigation Board (CAB), the Marshall Space Flight Center was asked to perform engineering analyses of internal flows in the port wing. The aero-thermodynamics team was split into internal flow and external flow teams with the support being divided between shorter timeframe engineering methods and more complex computational fluid dynamics. In order to gain a rough order of magnitude type of knowledge of the internal flow in the port wing for various breach locations and sizes (as theorized by the CAB to have caused the Columbia re-entry failure), a bulk venting model was required to input boundary flow rates and pressures to the computational fluid dynamics (CFD) analyses. This paper summarizes the modeling that was done by MSFC in Thermal Desktop. A venting model of the entire Orbiter was constructed in FloCAD based on Rockwell International s flight substantiation analyses and the STS-107 reentry trajectory. Chemical equilibrium air thermodynamic properties were generated for SINDA/FLUINT s fluid property routines from a code provided by Langley Research Center. In parallel, a simplified thermal mathematical model of the port wing, including the Thermal Protection System (TPS), was based on more detailed Shuttle re-entry modeling previously done by the Dryden Flight Research Center. Once the venting model was coupled with the thermal model of the wing structure with chemical equilibrium air properties, various breach scenarios were assessed in support of the aero-thermodynamics team. The construction of the coupled model and results are presented herein.

  1. Investigation of NPP behavior in case of loss of coolant accident based on comparison of different ASTEC computer code versions

    The paper presents the work performed at the Institute for Nuclear Research and Nuclear Energy (INRNE) and Bhabha Atomic Research Centre (BARC), India in the frame of SARNET2 project. The performed work continues the effort in the field of nuclear safety and cooperation between INRNE-BAS and BARC. The main target is development and validation of ASTEC (Accident Source Term Evaluation Code) at the further, a tool for level-2 PSA analysis for better understanding of accident progression during in-vessel phase until reactor vessel failure. (authors)

  2. Integrating engineering principles into the medico-legal investigation of a rare fatal rollover car accident involving complex dynamics.

    Grassi, Vincenzo M; Castagnola, Flaminia; Miscusi, Massimo; De-Giorgio, Fabio

    2016-09-01

    Rollover car accidents can be the result of forceful steering or hitting an obstacle that acts like a ramp. Mortality from this type of car accident is particularly high, especially when occupants are thrown out of the vehicle. We report a case of a 67-year-old man who died after a rollover accident that occurred when he was driving a car equipped with a glass moonroof. He was found inside his car with his safety belt correctly fastened and the roof shattered. At autopsy, a wide avulsion injury of the head was observed, which was associated with an atlanto-axial dislocation and full-thickness fracture of the cervical body and posterior facet joints of the seventh cervical vertebra. The data collected at the scene of the accident were integrated with the autopsy results to yield a forensic engineering reconstruction. This reconstruction elucidated the dynamics of the event and correctly ascribed the lesions observed at autopsy to the phases of the rollover. Afterward, an analysis of the scientific literature concerning rollover crash tests was conducted to understand why the driver sustained fatal injuries even though his seatbelt was properly fastened. PMID:27406628

  3. 关于护理差错事故的调查分析及防范措施%Investigation and analysis of nursing accidents and precaution measures

    马忠金

    2012-01-01

    Objective To investigate and analyze the cause of nursing accident errors and propose precaution measures.Methods From the year of 1991 to 2011,109 nurses who made nursing accident errors were analyzed statistically by their education background and occupational tenure and those errors were categorized according to records. Results Nursing accident errors was negatively related to education background and occupational tenure.Nursing accident errors was also relative to the fixed habits.Conclusions Continual learning,learning from lessons,overcoming fixed habits are all effective measures in preventing nursing accident errors.%目的 调查分析护理差错事故发生的原因并提出防范措施.方法 对我院1991年1月1日到2011年1月1日发生109例的护理差错事故的护理人员按学历、护龄足以统计并依据当时的记录描述对护理差错事故归类分析.结果 护理差错事故的发生与学历、工龄(工作半年以上)成相关负性增长,护理差错事故大多与习惯性定势有关.结论 不断学习、吸取经验教训、克服习惯性定势是防范护理差错事故的有效措施.

  4. Investigation of a fatal airplane crash: autopsy, computed tomography, and injury pattern analysis used to determine who was steering the plane at time of accident. A case report

    Høyer, Christian Bjerre; Nielsen, Trine Skov; Nagel, Lise Loft;

    2012-01-01

    A fatal accident is reported in which a small single-engine light airplane crashed. The airplane carried two persons in the front seats, both of whom possessed valid pilot certificates. Both victims were subject to autopsy, including post-mortem computed tomography scanning (PMCT) prior to the...... autopsy. The autopsies showed massive destruction to the bodies of the two victims but did not identify any signs of acute or chronic medical conditions that could explain loss of control of the airplane. PMCT, histological examination, and forensic chemical analysis also failed to identify an explanation...... for the crash. A detailed review of an airplane identical to the crashed airplane was performed in collaboration with the Danish Accident Investigation Board and the Danish National Police, National Centre of Forensic Services. The injuries were described using the abbreviated injury scale, the injury...

  5. Investigation of steam line break accident during the development of emergency operating procedures for WWER440/V230

    The results of thermal-hydraulic analyses of Steam Line Break (SLB) accident in supporting of symptom based emergency operating procedures are presented. This kind of analyses are designed to provide the response of monitored plant parameters to identify symptoms available to the operators, timing of the loss of critical safety functions and timing of operator actions to avoid the loss of critical safety functions or core damage. RELAP5/MOD3.2 computer code has been used to simulate the SLB accident in a WWER 440 NPP model. This model was developed at the Institute for Nuclear Research and Nuclear Energy for analyses of operational occurrences, abnormal events, and design bases scenarios. The model provides a significant analytical capability for the specialists working in the field of NPP safety. (authors)

  6. Utilization of the IAIA (Investigation and Analysis of Incidents and Accidents) method in the investigation of the P-36 platform accident; Utilizacao do metodo IAIA (Investigacao e Analise de Acidentes e Incidentes) na investigacao do acidente ocorrido na plataforma P-36

    Teles, Marcus de Barros [ARCE - Agencia Reguladora de Servicos Publicos Delegados do Estado do Ceara, Fortaleza, CE (Brazil)

    2004-07-01

    In the beginning of XXI century the Brazilian oil industry report a big accident involving that which was the biggest petroleum platform of the world. With capacity production of 180.000 barrels a day and capacity compression of 7,2 million cubic meter a day of natural gas, the off-shore platform P-36 was situated on Roncador field, in Campos basin, operating in 1360 meters of water. As consequences, eleven deaths with irreparable traumas to the families, friends and worker partners, one billion dollars in prejudices to brazilian country, environmental damages by oil leak and injuries to PETROBRAS reputation in Brazil and in the world. The method of investigation and analysis of incidents and accidents - IAIA is very wide and its philosophy contain a lot of topics, since basic concepts, investigation actions, analysis action and diagnosis by the general kind of fail. Using this method and taking advantage from the report elaborated by the commission organized by ANP - Agencia Nacional do Petroleo and DPC - Diretoria de Portos e Costas, responsible for the investigation and analysis of the accident occurred with P-36, this paper identify the direct and indirect causes of the accident, in attempt to avoid new similar situations. (author)

  7. Nuclear accidents

    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

  8. Radiation accidents

    Radiation accidents may be viewed as unusual exposure event which provide possible high exposure to a few people and, in the case of nuclear plants events, low exposure to large population. A number of radiation accidents have occurred over the past 50 years, involving radiation machines, radioactive materials and uncontrolled nuclear reactors. These accidents have resulted in number of people have been exposed to a range of internal and external radiation doses and those involving radioactive materials have involved multiple routs of exposure. Some of the more important accidents involving significant radiation doses or releases of radioactive materials, including any known health effects involves in it. An analysis of the common characteristics of accidents is useful resolving overarching issues, as has been done following nuclear power, industrial radiography and medical accidents. Success in avoiding accidents and responding when they do occur requires planning in order to have adequately trained and prepared health physics organization; well defined and developed instrument program; close cooperation among radiation protection experts, local and state authorities. Focus is given to the successful avoidance of accidents and response in the events they do occur. Palomares, spain in late 1960, Goiania, Brazil in 1987, Thule, Greenland in 1968, Rocky flats, Colorado in 1957 and 1969, Three mile island, Pennsylvania in 1979, Chernobyl Ukraine in april 1986, Kyshtym, former Soviet Union in 1957, Windscale, UK in Oct. 1957 Tomsk, Russian Federation in 1993, and many others are the important examples of major radiation accidents. (author)

  9. Investigation of tritium and radiocaesium in spring water and short precipitation after the Fukushima Dai-ichi Nuclear Power Plant accident

    Hydrogen explosion occurred at Fukushima Dai-ichi nuclear power plants in Japan on 12-15th March, 2011. At the same time, lots of radioactive materials have been released including tritium (T), and caused serious environmental impacts. In order to investigate the effect of the accident of Fukushima Dai-ichi nuclear power plant on environment, we collected the short precipitation(hourly collected precipitation) and spring water for several years after the accident. As to the precipitation collected, T and radiocaesium were measured by using liquid scintillation counter and high-purity germanium detector, respectively. Furthermore, we also measured the concentration of ions (Na+, Cl-, Ca2+, and SO42-) in spring water. From the above-mentioned matters, the following points have been obtained: (1) The variation of T concentration in recent three years (2012, 2013 and 2014) can be clarified. (2) The effect of the accident on spring water in mountains around the Fukushima prefecture is so small. (3) As to the short precipitation on 15th March, 2011, the activity of radiocaesium was not detected, but the activity of T was detected significantly. (author)

  10. 49 CFR 801.32 - Accident reports.

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Accident reports. 801.32 Section 801.32... PUBLIC AVAILABILITY OF INFORMATION Accident Investigation Records § 801.32 Accident reports. (a) The NTSB....S. civil transportation accidents, in accordance with 49 U.S.C. 1131(e). (b) These reports may...

  11. Report on summary results of the inspection of issues regarding the scope of the accident investigation of the TRISTAN Fire at the Brookhaven National Laboratory

    NONE

    1996-03-01

    The subject final report is provided to inform you of our findings and recommendations concerning our review of issues regarding the scope of the accident investigation of a March 31, 1994, fire at the Terrific Reactor Isotope Separator To Analyze Nuclides (TRISTAN) experiment at the Department of Energy (DOE) Brookhaven National Laboratory (BNL), Upton, New York. The Chicago Operations Office (CH) Manager appointed a Type B Accident Investigation Board (Board) to investigate the fire. In a June 16, 1994, letter to the Inspector General, DOE, the CH Manager requested the Inspector General to look into an allegation by a former Board member that senior Chicago management consciously violated the requirements of DOE Order 5484.1, {open_quotes}Environmental Protection, Safety, And Health Protection Information Reporting Requirements,{close_quotes} in attempting to control the investigation. The former Board member alleged that there was not a clear verbal agreement among the Board members regarding the focus of the scope of the investigation. He said that the Board Chairman wanted to focus on the physical causes of the fire, while he (the former Board member) believed that the Board should focus on the apparent management deficiencies that allowed TRISTAN to operate without a proper safety analysis and in violation of DOE orders for so many years.

  12. Investigation of the emergency nursing for patients with acute cerebrovascular accident%急性脑血管意外患者的急救护理

    张金燕

    2015-01-01

    Objective:To investigate and summarize the key points of nursing for acute cerebrovascular accident,and provide scientific basis for clinical nursing work in the future.Methods:84 cases of acute cerebral vascular accident patients were selected, and we the analyzed the emergency care and clinical datas of them retrospectively.Results:84 cases of acute cerebral vascular accident patients were improved in 73 cases(86.9%) through the emergency treatment,the disease aggravated 11 cases(13.1%). Conclusion:Timely and effective emergency care can reduce the mortality and morbidity of cerebrovascular accident patients,and reduce the incidence of complications.It plays an important role in the prognosis of patients.%目的:探讨总结急性脑血管意外的护理要点,为今后临床护理工作提供科学的依据。方法:收治急性脑血管意外患者84例,回顾性分析其急救护理及临床资料。结果:84例急性脑血管意外患者经抢救治疗,病情好转73例(86.9%),病情加重11例(13.1%)。结论:及时、有效的急救护理能够降低脑血管意外患者的病死率及致残率,同时有效降低并发症的发生率,对患者预后发挥重要的作用。

  13. Safety criteria and guidelines for MSR accident analysis

    Accident analysis for Molten Salt Reactor (MSR) has been investigated at ORNL for MSRE in 1960s. Since then, safety criteria or guidelines have not been defined for MSR accident analysis. Regarding the safety criteria, the authors showed one proposal in this paper. In order to establish guidelines for MSR accident analysis, we have to investigate all possible accidents. In this paper, the authors describe the philosophy for accident analysis, and show 40 possible accidents. They are at first classified as external cause accidents and internal cause accidents. Since the former ones are generic accidents, we investigate only the latter ones, and categorize them to 4 types, such as power excursion accident, flow decrease accident, fuel-salt leak accident, and other accidents mostly specific to MSR. Each accident is described briefly, with some numerical results by the authors. (author)

  14. Experimental and theoretical investigation of melt propagation in rubble beds for application in severe-accident analyses

    One of the consequences of core heatup and degradation during severe accidents is the formation of a rubblized bed, composed of various materials and particles of different size. As a result of continuous heatup due to the decay heat generation augmented by oxidation reaction, individual materials reach their melting temperatures, liquefy, and relocate downward to cooler core regions. Whereas the relocation of most of the low-melting temperature materials occurs very quickly, the melting process of ZrO2 and UO2, their relocation, and interaction with solid debris particles is relatively slow. In particular, the release of molten fuel from the corium may be delayed due to the formation of a solid crust separating the molten fuel above from the lower reactor sections. Needless to say, the time history of fuel melting and release may have a profound effect on the overall accident consequences. The purpose of this paper is to present the results of experimental simulation and analytical/numerical analysis of the interaction between a rubble bed and a penetrating (and partially freezing) liquid. In the experiments, two different materials were used to stimulate a rubble bed consisting of spherical particles, i.e., paraffin and glass. The bed was subjected to molten paraffin droplets, injected from the top. The droplets were partially freezing when flowing through the bed. The combined melt relocation and solidification processes were studied parametrically, including the effect of such parameters as, bed porosity, melt temperature, relative subcooling of solid particles, velocity, and mass flow rate

  15. Experimental investigation of capacity for work of protective outer skin of microfuel particles in reference of heavy accident conditions of lightwater reactors

    One investigated into the service ability of the silicon carbide coated particle fuels as applied to the light-water reactor loss-of-coolant severe accidents. According to the tests performed in the synthetic steam-and-gas medium representing the products of propane combustion in oxygen within 730-1670 deg C range, the particle fuel coating under up to 1590 deg C temperature showed high corrosion resistance and integrity. The particle fuel essential vulnerability to damage up to 25% was observed under 1670 deg C. The particle fuels satisfied advantageously the tests with up to 800-1600 deg C heating in air followed by the abrupt cooling in water

  16. Report of the investigation of the accident at the MIDAS MYTH/MILAGRO Trailer Park on Rainier Mesa at Nevada Test Site on February 15, 1984

    Fourteen persons were injured, one fatally, when the ground upon which they were working collapsed, forming a subsidence crater in the recording trailer park of the MIDAS MYTH/MILAGRO nuclear weapons effects test on Rainier Mesa at the US Department of Energy's Nevada Test Site on February 15, 1984. Those persons injured were contractor and laboratory employees from Reynolds Electrical and Engineering Co., Inc. (REECo), Pan American World Services, Inc. (PANAM), and the Los Alamos National Laboratory (LANL). This report presents the results of an investigation into the causes, effects, and response to the accident. 42 figures

  17. Report of the investigation of the accident at the MIDAS MYTH/MILAGRO Trailer Park on Rainier Mesa at Nevada Test Site on February 15, 1984

    1984-04-09

    Fourteen persons were injured, one fatally, when the ground upon which they were working collapsed, forming a subsidence crater in the recording trailer park of the MIDAS MYTH/MILAGRO nuclear weapons effects test on Rainier Mesa at the US Department of Energy's Nevada Test Site on February 15, 1984. Those persons injured were contractor and laboratory employees from Reynolds Electrical and Engineering Co., Inc. (REECo), Pan American World Services, Inc. (PANAM), and the Los Alamos National Laboratory (LANL). This report presents the results of an investigation into the causes, effects, and response to the accident. 42 figures.

  18. Occupational accidents aboard merchant ships

    Hansen, H.L.; Nielsen, D.; Frydenberg, Morten

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may be...... initiated. Methods: The study is a historical follow up on occupational accidents among crew aboard Danish merchant ships in the period 1993–7. Data were extracted from the Danish Maritime Authority and insurance data. Exact data on time at risk were available. Results: A total of 1993 accidents were...... identified during a total of 31 140 years at sea. Among these, 209 accidents resulted in permanent disability of 5% or more, and 27 were fatal. The mean risk of having an occupational accident was 6.4/100 years at sea and the risk of an accident causing a permanent disability of 5% or more was 0.67/100 years...

  19. Database on aircraft accidents

    The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published the report '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 the report, 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 latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. This year, the database was revised by adding aircraft accidents in 2010 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2011 database for latest 20 years from 1991 to 2010. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for latest 20 years from 1991 to 2010 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 2011 revised database for latest 20 years from 1991 to 2010 shows the followings. The trend of the 2011 database changes little as compared to the last year's one. (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. 4 large fixed-wing aircraft accidents, 58 small fixed-wing aircraft accidents, 5 large bladed aircraft accidents and 114 small bladed aircraft accidents occurred. The relevant accidents for evaluating

  20. 一起道路交通事故引发重大火灾的调查与分析%Fire investigation and analysis of a road traffic accident

    刘兴华

    2013-01-01

    通过调查和重建一起道路交通事故引发重大火灾的过程,分析引起事故的原因,提出预防和应对此类安全事故处理的措施和意见.%Through investigation and reconstruction a great fire caused by a road traffic accident, analyze the cause of the accident reason, put forward measures and opinions to prevent similar accident.

  1. Accident Statistics

    Department of Homeland Security — Accident statistics available on the Coast Guard’s website by state, year, and one variable to obtain tables and/or graphs. Data from reports has been loaded for...

  2. Investigation of Acute Poisoning Accident Caused by Hydrogen Sulfide%一起急性硫化氢中毒事故的调查

    周小涛; 熊田甜

    2013-01-01

      目的介绍一起因硫氢化钠与外环境酸性污水反应导致的硫化氢中毒死亡事件的调查处理情况。方法2006年11月29日, J 市 G 区发生一起以双眼及上呼吸道刺激为主要症状,伴有胸闷、憋气、头晕、恶心干呕等全身症状的中毒事故,造成1人死亡,一人昏迷,一人头晕。对患者进行临床诊断,对外环境相关有毒物质进行检测,模拟有毒气体的化学反应。结果三名患者临床表现符合硫化氢中毒后症状;事发后2h,现场空气硫化氢浓度为0.87mg/m3,现场含酸污水与原料硫化钠模拟试验可以检测到反应产物硫化氢气体。结论中毒主要原因是硫氢化钠被外环境酸性污水浸泡,分解后释放出硫化氢,加上作业工人防护不到位,导致吸入高浓度硫化氢中毒。%  Objective: To introduce an Accident Caused by Hydrogen Sulfide.   Methods: In some factory happened a poisoning accident,which resulted in death and casualty,the folowing measures such as Medical treatment, field investigation, laboratory detection were carried out immediately.   Results: Three victims were diagnosed as hydrogen sulfide poisoning; 2 hours after the accident, the concentration of hydrogen sulfide in spot was 0.87mg/m3, and hydrogen sulfide was detected positive in Simulation test.   Conclusion: The acute poisoning accident was caused by Hydrogen sulfide, which was released when sodium hydrosulfide mixed with hydrochloric acid. When the victims were lack of enough safeguard, high concentrations of Hydrogen sulfide were inhaled and resulted poisoning.

  3. Simulating Experimental Investigation on the Safety of Nuclear Heating Reactor in Loss—of —Coolant Accidents

    ZhanjieXu

    1996-01-01

    The 5MW low temperature nuclear heating reactor (NHR-5) is a new and advanced type of nuclear reactor developed by Institute of Nuclear Energy Technology(INET) of Tisinghuan University of CHina in 1989,Its main loop is a thermal-hydraulic system with natural circulation.This paper studies the safety of NHR under the condition of loss-of -coolant accidents(LOCAs) by means of simulant experiments.First,the Background and necessity of the experiments are presented.then the experimental system,including the thermal-hydraulic system and the data collection system,and similarity criteria are introduced.Up to now ,the discharge experiments with the residual heating power(20% rated heating power)have been carried out on the experimental system,The system prameters including circulation flow rate,system pressure,system temperature,void fraction,discharge mass and so on have been recorded and analyzed.Based on the results of the experiments,the conclusionas are shown as follos:on the whole,the reactor is safe under the condition of LOCAs,but the thermal vacillations resulting from the vibration of the circulation flow rate are disadvantageous to the internal parts of the reactor core.

  4. Experimental investigation of depressurization wave propagation in a horizontal channel during a simulated loss-of-coolant accident

    A model of the WWER-440 pressure vessel in a scale of 1:8 was built for experimental research of loss-of-coolant accidents. The model was modified for the study of the characteristics of the depressurization wave produced as a result of the rapid pressure drop within 10 and 40 GPa/s. The results show that for initial temperatures above 240 degC, pressure falls considerably below the saturation limit. Thus, thermodynamic imbalance of the process should be taken into consideration. The pressure drop below the saturation limit is mainly affected by the initial temperature and the pressure drop rate. Rapid pressure drop in hot water is halted by explosive generation of the steam phase in the overheated liquid. This causes a short-time pressure increase followed by a relatively long interval of quasistatic pressure. It was also confirmed that the velocity of depressurization wave propagation in a liquid approximately equals the velocity of sound. (Z.M.). 7 figs., 1 tab., 16 refs

  5. Touch DNA Testing in Car Accident Investigation%交通事故中汗潜指印DNA检验

    纪中华

    2015-01-01

    This paper introduces analysis of fingerprint DNA collected from accidental vehicles. Fingerprint on the steering wheel and gear lever was developed with 502 glue, and EZ-tape was used to collect the shed cells. DNA was extracted with Chelex-100 and magnetic bead-based method, and DNA purification and quantification were performed. PCR reaction was optimized by properly adding 4μL of DNA template and increasing PCR cycle number to 32. PCR products were run in ABI3130 with 10s extension of the injection time, and STR profiles were determined. This method had been successfully applied in 2 car accidents and the drivers were identified.%为成功提取交通事故中的指印 DNA,用502胶熏显指印,用 EZ-tape 胶带采集车辆方向盘及变速杆等处的脱落细胞,然后 Chelex-100法与磁珠法结合提取 DNA,延长保温时间。DNA 定量,根据 DNA 浓度调整PCR 反应体系,通过适当增加 PCR 循环数、增加 PCR 产物量及延长进样时间等方法,成功地对指印 DNA 做了 STR 分型,确定了两起交通事故中的驾驶人。

  6. 交通事故中汗潜指印DNA检验%Touch DNA Testing in Car Accident Investigation

    纪中华

    2015-01-01

    This paper introduces analysis of fingerprint DNA collected from accidental vehicles. Fingerprint on the steering wheel and gear lever was developed with 502 glue, and EZ-tape was used to collect the shed cells. DNA was extracted with Chelex-100 and magnetic bead-based method, and DNA purification and quantification were performed. PCR reaction was optimized by properly adding 4μL of DNA template and increasing PCR cycle number to 32. PCR products were run in ABI3130 with 10s extension of the injection time, and STR profiles were determined. This method had been successfully applied in 2 car accidents and the drivers were identified.%为成功提取交通事故中的指印 DNA,用502胶熏显指印,用 EZ-tape 胶带采集车辆方向盘及变速杆等处的脱落细胞,然后 Chelex-100法与磁珠法结合提取 DNA,延长保温时间。DNA 定量,根据 DNA 浓度调整PCR 反应体系,通过适当增加 PCR 循环数、增加 PCR 产物量及延长进样时间等方法,成功地对指印 DNA 做了 STR 分型,确定了两起交通事故中的驾驶人。

  7. Experimental investigation on the chemical precipitation generation under the loss of coolant accident of nuclear power plants

    The PWR containment buildings are designed to facilitate core cooling in the event of a Loss of Coolant Accident (LOCA). The cooling process requires water discharged from the break and containment spray to be collected in a sump for recirculation. The containment sump contains screens to protect the components of the Emergency Core Cooling System (ECCS) and Containment Spray System (CSS) from debris. Since the containment materials may dissolve or corrode when exposed to the reactor coolant and spray solutions, various chemical precipitations can be generated in a post-LOCA environment. These chemical precipitations may become another source of debris loading to be considered in sump screen performance and downstream effects. In this study, new experimental methodology to predict the type and quantity of chemical precipitations has been developed. To generate the plant-specific chemical precipitation in a post-LOCA environment, the plant specific chemical condition of the recirculation sump during post-LOCA is simulated with the experimental reactor for the chemical effect. The plant-specific containment materials are used in the present experiment such as glass fibers, concrete blocks, aluminum specimens, and chemical reagent - boric acid, spray additives or buffering chemicals (sodium hydroxide, Tri-Sodium Phosphate (TSP), or others). The inside temperature of the reactor is controlled to simulate the plant-specific temperature profile of the recirculation sump. The total amount of aluminum released from aluminum specimens is evaluated by ICP-AES analysis to determine the amount of AlOOH and NaAlSi3O8 which induce very adverse effect on the head loss across the sump screens. The amount of these precipitations generated in the present experimental study is compared with the results of WCAP-16530-NP-A. (authors)

  8. Use of PSA and severe accident assessment results for the accident management

    The objectives for this study are to investigate the basic principle or methodology which is applicable to accident management, by using the results of PSA and severe accident research, and also facilitate the preparation of accidents management program in the future. This study was performed as follows: derivation of measures for core damage prevention, derivation of measures for accident mitigation, application of computerized tool to assess severe accident management

  9. Preventing accidents at intake towers

    Villegas, F. (INTEGRAL S.A., Medellin, CO (United States))

    1994-03-01

    Strong air blow-outs occurring in the intake tower of Guatape Hydroelectric Power Plant in Colombia have caused two serious accidents recently. The causes of the accidents were investigated and recommendations are made here to prevent future repetitions of these dangerous events. (UK)

  10. Occupational accidents aboard merchant ships

    Hansen, H; Nielsen, D; Frydenberg, M

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may be initiated.

  11. Hindsight Bias in Cause Analysis of Accident

    Atsuo Murata; Yasunari Matsushita

    2014-01-01

    It is suggested that hindsight becomes an obstacle to the objective investigation of an accident, and that the proper countermeasures for the prevention of such an accident is impossible if we view the accident with hindsight. Therefore, it is important for organizational managers to prevent hindsight from occurring so that hindsight does not hinder objective and proper measures to be taken and this does not lead to a serious accident. In this study, a basic phenomenon potentially related to accidents, that is, hindsight was taken up, and an attempt was made to explore the phenomenon in order to get basically insights into the prevention of accidents caused by such a cognitive bias.

  12. CAMS: Computerized Accident Management Support

    The OECD Halden Reactor Project has initiated a new research programme on computerised accident management support, the so-called CAMS project (CAMS = Computerized Accident Management Support). This work will investigate the possibilities for developing systems which provide more extensive support to the control room staff and technical support centre than the existing SPDS (Safety Parameter Display System) type of systems. The CAMS project will utilize available simulator codes and the capabilities of computerized tools to assist the plant staff during the various accident stages including: identification of the accident state, assessment of the future development of the accident, and planning accident mitigation strategies. This research programme aims at establishing a prototype system which can be used for experimental testing of the concept and serve as a tool for training and education in accident management. The CAMS prototype should provide support to the staff when the plant is in a normal state, in a disturbance sate, and in an accident state. Even though better support in an accident state is the main goal of the project, it is felt to be important that the staff is familiar with the use of the system during normal operation, when they utilize the system during transients

  13. The management of accidents

    R. B. Ward

    2009-01-01

    Full Text Available Purpose: This author’s experiences in investigating well over a hundred accident occurrences has led to questioning how such events can be managed - - - while immediately recognising that the idea of managing accidents is an oxymoron, we don’t want to manage them, we don’t want not to manage them, what we desire is not to have to manage not-them, that is, manage matters so they don’t happen and then we don’t have to manage the consequences.Design/methodology/approach: The research will begin by defining some common classes of accidents in manufacturing industry, with examples taken from cases investigated, and by working backwards (too late, of course show how those involved could have managed these sample events so they didn’t happen, finishing with the question whether any of that can be applied to other situations.Findings: As shown that the management actions needed to prevent accidents are control of design and application of technology, and control and integration of people.Research limitations/implications: This paper has shown in some of the examples provided, management actions have been know to lead to accidents being committed by others, lower in the organization.Originality/value: Today’s management activities involve, generally, the use of technology in many forms, varying from simple tools (such as knives to the use of heavy equipment, electric power, and explosives. Against these we commit, in control of those items, the comparatively frail human mind and body, which, again generally, does succeed in controlling these resources, with (another generality by appropriate management. However, sometimes the control slips and an accident occurs.

  14. Expert meeting with the Belgoprocess Inc. on the fire and explosion accident of the asphalt solidification facility. Search and investigation on cause elucidation and reoccurrence control for the fire and explosion accident of the asphalt solidification facility. A visiting report on abroad

    In order to investigate in detail on fire cause materials, test results of thermal analysis on waste liquids, and flow of affairs relating to the fire accident (15th December, 1981) of the Euro Bitum Plant (an asphalt solidification facility of the middle level wastes) settled at the Eurochemic reprocessing work in the Kingdom of Belgium, resemble to the present accident, 4 members of the Cause Elucidation Group and Mr. Kaneko, director of the Paris Office of PNC visited to Belgium to hold a meeting with experts of the Belgoprocess Inc. for 4 days. In this meeting, after exchanging mutual detail informations on accident occurred at the Euro Bitum Plant and fire and explosion accident of the asphalt solidification facility, some discussions on cause supposition of the present accident. For cause of the fire, mutual differences were found. As a state at occurring fires was much resemble, their followed states seemed to be extremely different on responses of operators to fire-extinguishing action, filter exchanging and so forth. As finishing to recover the plant after 1 month passed from the accident to restart its operation, the Belgoprocess, Inc. has conducted some improvements of the facility such as sufficiency of fire extinguishing apparatus, addition and improvements of fire detecting means, direct measurement of solid temperature and so on, as well as reinforcement of thermal analysis procedure and renewal to new apparatus. Although no special supposition on cause of the fire at this meeting, a lot of items to learn such as operation system, responses after accident, and so forth were acquired. (G.K.)

  15. Tchernobyl accident

    First, R.M.B.K type reactors are described. Then, safety problems are dealt with reactor control, behavior during transients, normal loss of power and behavior of the reactor in case of leak. A possible scenario of the accident of Tchernobyl is proposed: events before the explosion, possible initiators, possible scenario and events subsequent to the core meltdown (corium-concrete interaction, interaction with the groundwater table). An estimation of the source term is proposed first from the installation characteristics and the supposed scenario of the accident, and from the measurements in Europe; radiological consequences are also estimated. Radioactivity measurements (Europe, Scandinavia, Western Europe, France) are given in tables (meteorological maps and fallouts in Europe). Finally, a description of the site is given

  16. Accident: Reminder

    2003-01-01

    There is no left turn to Point 1 from the customs, direction CERN. A terrible accident happened last week on the Route de Meyrin just outside Entrance B because traffic regulations were not respected. You are reminded that when travelling from the customs, direction CERN, turning left to Point 1 is forbidden. Access to Point 1 from the customs is only via entering CERN, going down to the roundabout and coming back up to the traffic lights at Entrance B

  17. Experimental investigation of the focusing effect of the metallic layer heat transfer in a severe accident condition

    Focusing effect of the metallic layer was investigated experimentally for Rayleigh numbers ranging 8.49×107∼5.49×109 and aspect ratios 0.135∼0.540 respectively. The height of the side wall was varied. High Rayleigh numbers were achieved using mass transfer experiments based on the heat and mass transfer analogy. Piecewise electrodes are adopted to measure the local average mass transfer. An electrical resistance was attached to the top wall so as to mimic top hotter wall condition. The measured results and existing heat transfer correlations were in good agreements. As the height reduces, the focusing effect becomes severe, especially at the corner near the bottom. (author)

  18. How to reduce the number of accidents

    2012-01-01

    Among the safety objectives that the Director-General has established for CERN in 2012 is a reduction in the number of workplace accidents.   The best way to prevent workplace accidents is to learn from experience. This is why any accident, fire, instance of pollution, or even a near-miss, should be reported using the EDH form that can be found here. All accident reports are followed up. The departments investigate all accidents that result in sick leave, as well as all the more common categories of accidents at CERN, essentially falls (slipping, falling on stairs, etc.), regardless of whether or not they lead to sick leave. By studying the accident causes that come to light in this way, it is possible to take preventive action to avoid such accidents in the future. If you have any questions, the HSE Unit will be happy to answer them. Contact us at safety-general@cern.ch. HSE Unit

  19. Containment severe accident thermohydraulic phenomena

    This report describes and discusses the containment accident progression and the important severe accident containment thermohydraulic phenomena. The overall objective of the report is to provide a rather detailed presentation of the present status of phenomenological knowledge, including an account of relevant experimental investigations and to discuss, to some extent, the modelling approach used in the MAAP 3.0 computer code. The MAAP code has been used in Sweden as the main tool in the analysis of severe accidents. The dependence of the containment accident progression and containment phenomena on the initial conditions, which in turn are heavily dependent on the in-vessel accident progression and phenomena as well as associated uncertainties, is emphasized. The report is in three parts dealing with: * Swedish reactor containments, the severe accident mitigation programme in Sweden and containment accident progression in Swedish PWRs and BWRs as predicted by the MAAP 3.0 code. * Key non-energetic ex-vessel phenomena (melt fragmentation in water, melt quenching and coolability, core-concrete interaction and high temperature in containment). * Early containment threats due to energetic events (hydrogen combustion, high pressure melt ejection and direct containment heating, and ex-vessel steam explosions). The report concludes that our understanding of the containment severe accident progression and phenomena has improved very significantly over the parts ten years and, thereby, our ability to assess containment threats, to quantify uncertainties, and to interpret the results of experiments and computer code calculations have also increased. (au)

  20. Investigations of Aluminum-Doped Self-Healing Zircaloy Surfaces in Context of Accident-Tolerant Fuel Cladding Research

    Carr, James; Vasudevamurthy, Gokul; Snead, Lance; Hinderliter, Brian; Massey, Caleb

    2016-05-01

    We present here some important results investigating aluminum as an effective surface dopant for increased oxidation resistance of zircaloy nuclear fuel cladding. At first, the transport behavior of aluminum into reactor grade zircaloy was studied using simple diffusion couples at temperatures greater than 770 K. The experiments revealed the formation of tens of microns thick graded Zr-Al layers. The activation energy of aluminum in zircaloy was found to be ~175 kJ/mol (~1.8 eV), indicating the high mobility of aluminum in zircaloy. Subsequently, aluminum sputter-coated zircaloy coupons were heat-treated to achieve surface doping and form compositionally graded layers. These coupons were then tested in steam environments at 1073 and 1273 K. The microstructure of the as-fabricated and steam-corroded specimens was compared to those of pure zircaloy control specimens. Analysis of data revealed that aluminum effectively competed with zircaloy for oxygen up until 1073 K blocking oxygen penetration, with no traces of large scale spalling, indicating mechanically stable interfaces and surfaces. At the highest steam test temperatures, aluminum was observed to segregate from the Zr-Al alloy under layers and migrate to the surface forming discrete clusters. Although this is perceived as an extremely desirable phenomenon, in the current experiments, oxygen was observed to penetrate into the zirconium-rich under layers, which could be attributed to formation of surface defects such as cracks in the surface alumina layers.

  1. Long-term investigations of radiocaesium activity concentrations in carps in north Croatia after the Chernobyl accident

    Franic, Z

    2007-01-01

    Long-term investigations of radiocaesium activity concentrations in carps in the Republic of Croatia are presented. The radiocaesium levels in carps decreased exponentially and the effective ecological half-life of 137Cs in carps was estimated to be about 1 year for 1987-2002 period and 5 years for 1993-2005 period. The observed 134Cs:137Cs activity ratio in carps has been found to be similar to the ratio that has been observed in other environmental samples. Concentration factor for carps (wet weight) was roughly estimated to be 128 +/- 74 Lkg-1, which is in reasonable agreement with model prediction based on K+ concentrations in water. Estimated annual effective doses received by 134Cs and 137Cs intake due to consumption of carps for an adult member of Croatian population are small, per caput dose for the 1987 - 2005 estimated to be 0.5 +/- 0.2 microSv. Due to minor freshwater fish consumption in Croatia and low radiocaesium activity concentrations in carps, it can be concluded that carps consumption was no...

  2. Investigations of Aluminum-Doped Self-Healing Zircaloy Surfaces in Context of Accident-Tolerant Fuel Cladding Research

    Carr, James; Vasudevamurthy, Gokul; Snead, Lance; Hinderliter, Brian; Massey, Caleb

    2016-06-01

    We present here some important results investigating aluminum as an effective surface dopant for increased oxidation resistance of zircaloy nuclear fuel cladding. At first, the transport behavior of aluminum into reactor grade zircaloy was studied using simple diffusion couples at temperatures greater than 770 K. The experiments revealed the formation of tens of microns thick graded Zr-Al layers. The activation energy of aluminum in zircaloy was found to be ~175 kJ/mol (~1.8 eV), indicating the high mobility of aluminum in zircaloy. Subsequently, aluminum sputter-coated zircaloy coupons were heat-treated to achieve surface doping and form compositionally graded layers. These coupons were then tested in steam environments at 1073 and 1273 K. The microstructure of the as-fabricated and steam-corroded specimens was compared to those of pure zircaloy control specimens. Analysis of data revealed that aluminum effectively competed with zircaloy for oxygen up until 1073 K blocking oxygen penetration, with no traces of large scale spalling, indicating mechanically stable interfaces and surfaces. At the highest steam test temperatures, aluminum was observed to segregate from the Zr-Al alloy under layers and migrate to the surface forming discrete clusters. Although this is perceived as an extremely desirable phenomenon, in the current experiments, oxygen was observed to penetrate into the zirconium-rich under layers, which could be attributed to formation of surface defects such as cracks in the surface alumina layers.

  3. Transportation accidents

    Predicting the possible consequences of transportation accidents provides a severe challenge to an analyst who must make a judgment of the likely consequences of a release event at an unpredictable time and place. Since it is impractical to try to obtain detailed knowledge of the meteorology and terrain for every potential accident location on a route or to obtain accurate descriptions of population distributions or sensitive property to be protected (data which are more likely to be more readily available when one deals with fixed-site problems), he is constrained to make conservative assumptions in response to a demanding public audience. These conservative assumptions are frequently offset by very small source terms (relative to a fixed site) created when a transport vehicle is involved in an accident. For radioactive materials, which are the principal interest of the authors, only the most elementary models have been used for assessing the consequences of release of these materials in the transportation setting. Risk analysis and environmental impact statements frequently have used the Pasquill-Gifford/gaussian techniques for releases of short duration, which are both simple and easy to apply and require a minimum amount of detailed information. However, after deciding to use such a model, the problem of selecting what specific parameters to use in specific transportation situations still presents itself. Additional complications arise because source terms are not well characterized, release rates can be variable over short and long time periods, and mechanisms by which source aerosols become entrained in air are not always obvious. Some approaches that have been used to address these problems will be reviewed with emphasis on guidelines to avoid the Worst-Case Scenario Syndrome

  4. Investigations on the safety of radioactive materials transport. Pt. 2. Modeling of the radiological consequences in the vicinity of an accident. Final report on the working package 2

    One aim of this project 3611R03300 was to analyse methods and procedures accord-ing to state-of-the-art technology concerning their applicability to assess the radiologi-cal consequences in the near vicinity of a transport accident. The analysis focusses on the dispersion models used for the airborne radionuclides released during an accident. In view of the large amount of simulations needed for a probabilistic assessment of the accident's radiological impact, simplified methods to calculate nuclide concentrations and deposition rates for the near vicinity were searched. Additionally, conservative fac-tors were determined to convert the results valid for 150 m distance to the accident, which was the shortest distance examined in the Transportstudie Konrad 2009, to the near vicinity (20 m distance).

  5. 46 CFR 4.03-1 - Marine casualty or accident.

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Marine casualty or accident. 4.03-1 Section 4.03-1... AND INVESTIGATIONS Definitions § 4.03-1 Marine casualty or accident. Marine casualty or accident means— (a) Any casualty or accident involving any vessel other than a public vessel that— (1) Occurs...

  6. Estimating the Influence of Accident Related Factors on Motorcycle Fatal Accidents using Logistic Regression (Case Study: Denpasar-Bali

    Wedagama D.M.P.

    2010-01-01

    Full Text Available In Denpasar the capital of Bali Province, motorcycle accident contributes to about 80% of total road accidents. Out of those motorcycle accidents, 32% are fatal accidents. This study investigates the influence of accident related factors on motorcycle fatal accidents in the city of Denpasar during period 2006-2008 using a logistic regression model. The study found that the fatality of collision with pedestrians and right angle accidents were respectively about 0.44 and 0.40 times lower than collision with other vehicles and accidents due to other factors. In contrast, the odds that a motorcycle accident will be fatal due to collision with heavy and light vehicles were 1.67 times more likely than with other motorcycles. Collision with pedestrians, right angle accidents, and heavy and light vehicles were respectively accounted for 31%, 29%, and 63% of motorcycle fatal accidents.

  7. ASTEC investigations of severe core damage behaviour of VVER-1000 in case of loss of coolant accident along with Station-Black-Out

    Groudev, Pavlin, E-mail: pavlinpg@inrne.bas.bg [INRNE – BAS, Institute for Nuclear Research and Nuclear Energy – Bulgarian Academy of Sciences, Tzarigradsko shaussee 72, Sofia 1784 (Bulgaria); Atanasova, Boryana [INRNE – BAS, Institute for Nuclear Research and Nuclear Energy – Bulgarian Academy of Sciences, Tzarigradsko shaussee 72, Sofia 1784 (Bulgaria); Chatterjee, Barun; Lele, Hemant G. [BARC, Bhabha Atomic Research Centre, Reactor Safety Division, Mumbai 400085 (India)

    2014-06-01

    Severe accident analysis of a reactor is an important aspect for evaluation of source term. Analyses have been carried out for VVER-1000 V320 reactor following LOCA along with Station-Black-Out using the severe accident code ASTEC. The predictions of different severe accident parameters like vessel rupture time, hydrogen and corium production and radioactivity release to containment have been compared for three break sizes. Since these predictions are dependent on different core degradation parameters and models, a sensitivity analysis is also carried out to study the effect of different core degradation parameters and models on severe core damage progression. LOCA analyses show a variation of degradation parameters which is a consequence of steam-rich and steam-starved conditions. All these calculations of VVER-1000 scenarios show that the ASTEC V2 code gives reliable and consistent results on this type of reactor, including its specifics like Zr1%Nb clad material and horizontal steam generators.

  8. Trend of Elevator-Related Accidents in Tehran

    Ali Khaji; Syyed Mohammad Ghodsi

    2014-01-01

    Background:   Elevator-related accidents are uncommon, but can cause significant injury. However, little data exist on these types of accidents. To compile and analyze accident data involving elevators in an effort to eliminate or at least significantly reduce such accidents. Methods: In this retrospective study we investigated 1,819 cases of elevator-related accidents during a four-year period (1999-2003) in Tehran. The data were obtained from the Tehran Safety Services & Fire Fighting Organ...

  9. Liuzhou city from 2006 to 2014 epidemiological characteristics of serious road traffic accident investigation%2006~2014年柳州市重大道路交通事故流行病学特征分析

    刘华; 李兵; 黄福文; 杨家有; 汤中飞; 邓旺生; 陆菊; 阮海林

    2015-01-01

    目的:调查分析柳州市重大道路交通事故发生的特点及规律,为控制和预防道路交通创伤提供科学依据。方法回顾性分析2006~2014年柳州市重大道路交通事故监测统计资料。结果(1)2006~2014年柳州市重大道路交通事故发生例数、死亡人数、受伤人数呈总体下降趋势。以1月份发生事故最多,占事故总数的11.5%;6月份发生事故最少,为6.8%。夜间19:00~23:00时事故发生最多,凌晨3:00~6:00时发生最少。(2)重大道路交通事故多数发生在平直道路上。(3)白天发生事故最多,夜间无路灯照明的路段事故伤亡和受伤人数明显高于夜间有路灯照明的路段。(4)重大道路交通事故发生的主要原因为人为因素,占总数的96.7%。结论减少重大道路交通事故发生,必须加强交通安全宣传、教育,提高全民安全意识;交管部门严格执法,尤其要加强交通事故高发时段、路段的管理;加强道路安全设施建设,改善交通环境。%Objective Investigation and analysis of Liuzhou significant characteristics and law of road traffic acci‐dents ,which will provide a scientific basis for control and prevention of road traffic trauma . Methods From 2006 to 2014 were retrospectively analyzed to collect statistics of serious road traffic accidents monitoring . Results (1)Liuzhou serious road traffic accident cases ,the number of deaths ,injury in the overall downward trend ,most ac‐cidents in January ,accounted for 11.5% of total number of accidents ,accidents in June at least (6 .8% ) .Most clearly 19 :00~23 :00 when the accident happened at night ,there was at least 3 :00~6:00 in the morning .(2)The most serious road traffic accident happened on the straight path .(3)Accidents occur most often during the day and night with no street lamp lighting significantly better than the number of road accident casualties and injuries have

  10. Risk and protection factors in fatal accidents.

    Dupont, Emmanuelle; Martensen, Heike; Papadimitriou, Eleonora; Yannis, George

    2010-03-01

    This paper aims at addressing the interest and appropriateness of performing accident severity analyses that are limited to fatal accident data. Two methodological issues are specifically discussed, namely the accident-size factors (the number of vehicles in the accident and their level of occupancy) and the comparability of the baseline risk. It is argued that - although these two issues are generally at play in accident severity analyses - their effects on, e.g., the estimation of survival probability, are exacerbated if the analysis is limited to fatal accident data. As a solution, it is recommended to control for these effects by (1) including accident-size indicators in the model, (2) focusing on different sub-groups of road-users while specifying the type of opponent in the model, so as to ensure that comparable baseline risks are worked with. These recommendations are applied in order to investigate risk and protection factors of car occupants involved in fatal accidents using data from a recently set up European Fatal Accident Investigation database (Reed and Morris, 2009). The results confirm that the estimated survival probability is affected by accident-size factors and by type of opponent. The car occupants' survival chances are negatively associated with their own age and that of their vehicle. The survival chances are also lower when seatbelt is not used. Front damage, as compared to other damaged car areas, appears to be associated with increased survival probability, but mostly in the case in which the accident opponent was another car. The interest of further investigating accident-size factors and opponent effects in fatal accidents is discussed. PMID:20159090

  11. Consequences of radioactive releases into the sea resulting from the accident at the Fukushima Dai-ichi nuclear power plant - Evolution of expert investigation according to the data available

    Laguionie, Philippe; Bailly du Bois, Pascal; Boust, D.; Fievet, B.; Garreau, Pierre; Connan, O.; Charmasson, Sabine; Arnaud, M; Duffa, Celine; Champion, D.

    2012-01-01

    The accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) in March 2011 led to an unprecedented direct input of artificial radioactivity into the marine environment. The Institute for Radioprotection and Nuclear Safety was requested by the French authorities to investigate the radioecological impact of this input, in particular the potential contamination of products of marine origin used for human consumption. This article describes the close link between the responses provided and ...

  12. Criticality Accident

    At a meeting of electric utility presidents in October, 1999, the Federation Power Companies (FEPCO) officially decided to establish a Japanese version of WANO, following the JCO criticality accident. The Japanese WANO is expected to be launched by the end of the year: initially, with some 30 private sector companies concerned with nuclear fuel. It is said that the private sector had to make efforts to ensure that safety was the most important value in management policy throughout the industry, and that comprehensive inspections would be implemented. In anything related to nuclear energy, sufficient safety checks are required even for the most seemingly trivial matters. Therefore, the All-Japan Council of Local Governments with Atomic Power Stations has already proposed to the Japanese government that it should enact the special law for nuclear emergency, providing that the unified responsibility for nuclear disaster prevention should be shifted to the national government, since the nuclear disaster was quite special from the viewpoint of its safety regulation and technical aspects. (G.K.)

  13. Development of a deformation and failure model for Zircaloy at high temperatures for light water reactor loss-of-coolant-accident investigations

    To describe Zircaloy-4 deformation and failure behaviour at high temperatures (600 to 14000C), the phenomenological model NORA was developed and verified against numerous experimental results. The model can be applied to the calculation of fuel rod cladding deformation during small and large break loss-of-coolant-accidents. (orig./RW)

  14. Investigation of rations of food of population and content of cesium radionuclides in foodstuffs and organism of farmers in Bryansk region after Chernobyl accident

    Data on dynamic content of cesium radionuclide in different foodstuffs and in organism of mature inhabitants were presented. Right after Chernobyl accident content of 137Cs in organism correlated with consumption of milk and meet products. For some time past content of 137Cs in organism correlated with levels of consumption of natural foodstuffs (mushrooms, berries, fishes, wilderness)

  15. Persistence on airline accidents.

    L. A. GIL-ALANA; Barros, C.P. (Carlos P.); J.R. Faria

    2009-01-01

    This paper analyses airline accidents data from 1927-2006. The fractional integration methodology is adopted. It is shown that airline accidents are persistent and (fractionally) cointegrated with airline traffic. Thus, there exists an equilibrium relation between air accidents and airline traffic, with the effect of the shocks to that relationship disappearing in the long run. Policy implications are derived for countering accidents events.

  16. Persistence in Airline Accidents

    Carlos Pestana Barros; João Ricardo Faria; Luis A. Gil-Alana

    2008-01-01

    This paper analyses airline accident data from 1927-2006, through fractional integration. It is shown that airline accidents are persistent and (fractionally) cointegrated with airline traffic. There exists a negative relation between air accidents and airline traffic, with the effect of the shocks to that relationship disappearing in the long run. Policy implications are derived for countering accident events.

  17. Scaling and design analyses of a scaled-down, high-temperature test facility for experimental investigation of the initial stages of a VHTR air-ingress accident

    A critical event in the safety analysis of the very high-temperature gas-cooled reactor (VHTR) is an air-ingress accident. This accident is initiated, in its worst case scenario, by a double-ended guillotine break of the coaxial cross vessel, which leads to a rapid reactor vessel depressurization. In a VHTR, the reactor vessel is located within a reactor cavity that is filled with air during normal operating conditions. Following the vessel depressurization, the dominant mode of ingress of an air—helium mixture into the reactor vessel will either be molecular diffusion or density-driven stratified flow. The mode of ingress is hypothesized to depend largely on the break conditions of the cross vessel. Since the time scales of these two ingress phenomena differ by orders of magnitude, it is imperative to understand under which conditions each of these mechanisms will dominate in the air ingress process. Computer models have been developed to analyze this type of accident scenario. There are, however, limited experimental data available to understand the phenomenology of the air-ingress accident and to validate these models. Therefore, there is a need to design and construct a scaled-down experimental test facility to simulate the air-ingress accident scenarios and to collect experimental data. The current paper focuses on the analyses performed for the design and operation of a 1/8th geometric scale (by height and diameter), high-temperature test facility. A geometric scaling analysis for the VHTR, a time scale analysis of the air-ingress phenomenon, a transient depressurization analysis of the reactor vessel, a hydraulic similarity analysis of the test facility, a heat transfer characterization of the hot plenum, a power scaling analysis for the reactor system, and a design analysis of the containment vessel are discussed.

  18. Modeling secondary accidents identified by traffic shock waves.

    Junhua, Wang; Boya, Liu; Lanfang, Zhang; Ragland, David R

    2016-02-01

    The high potential for occurrence and the negative consequences of secondary accidents make them an issue of great concern affecting freeway safety. Using accident records from a three-year period together with California interstate freeway loop data, a dynamic method for more accurate classification based on the traffic shock wave detecting method was used to identify secondary accidents. Spatio-temporal gaps between the primary and secondary accident were proven be fit via a mixture of Weibull and normal distribution. A logistic regression model was developed to investigate major factors contributing to secondary accident occurrence. Traffic shock wave speed and volume at the occurrence of a primary accident were explicitly considered in the model, as a secondary accident is defined as an accident that occurs within the spatio-temporal impact scope of the primary accident. Results show that the shock waves originating in the wake of a primary accident have a more significant impact on the likelihood of a secondary accident occurrence than the effects of traffic volume. Primary accidents with long durations can significantly increase the possibility of secondary accidents. Unsafe speed and weather are other factors contributing to secondary crash occurrence. It is strongly suggested that when police or rescue personnel arrive at the scene of an accident, they should not suddenly block, decrease, or unblock the traffic flow, but instead endeavor to control traffic in a smooth and controlled manner. Also it is important to reduce accident processing time to reduce the risk of secondary accident. PMID:26687540

  19. Severe accident phenomena

    Severe accidents are nuclear reactor accidents in which the reactor core is substantially damaged. The report describes severe reactor accident phenomena and their significance for the safety of nuclear power plants. A comprehensive set of phenomena ranging from accident initiation to containment behaviour and containment integrity questions are covered. The report is based on expertise gained in the severe accident assessment projects conducted at the Technical Research Centre of Finland (VTT). (49 refs., 32 figs., 12 tabs.)

  20. Barriers to learning from incidents and accidents

    Dechy, N.; Dien, Y.; Drupsteen, L.; Felicio, A.; Cunha, C; Roed-Larsen, S.; Marsden, E.; Tulonen, T.; Stoop, J.; Strucic, M.; Vetere Arellano, A.L.; Vorm, J.K.J. van der; Benner, L.

    2015-01-01

    This document provides an overview of knowledge concerning barriers to learning from incidents and accidents. It focuses on learning from accident investigations, public inquiries and operational experience feedback, in industrial sectors that are exposed to major accident hazards. The document discusses learning at organizational, cross-organizational and societal levels (impact on regulations and standards). From an operational standpoint, the document aims to help practitioners to identify...

  1. Experimental investigation of void distribution in Suppression Pool during the initial blowdown period of a Loss of Coolant Accident using air–water two-phase mixture

    Highlights: • Basic understanding of the venting phenomena in the SP during a LOCA was obtained. • A series of experiment is carried out using the PUMA-E test facility. • Two phases of experiments, namely, an initial and a quasi-steady phase were observed. • The maximum void penetration depth was experienced during the initial phase. - Abstract: During the initial blowdown period of a Loss of Coolant Accident (LOCA), the non-condensable gas initially contained in the BWR containment is discharged to the pressure suppression chamber through the blowdown pipes. The performance of Emergency Core Cooling System (ECCS) can be degraded due to the released gas ingestion into the suction intakes of the ECCS pumps. The understanding of the relevant phenomena in the pressure suppression chamber is important in analyzing potential gas intrusion into the suction intakes of ECCS pumps. To obtain the basic understanding of the relevant phenomena and the generic data of void distribution in the pressure suppression chamber during the initial blowdown period of a LOCA, tests with various blowdown conditions were conducted using the existing Suppression Pool (SP) tank of the integral test facility, called Purdue University Multi-Dimensional Integral Test Assembly for ESBWR applications (PUMA-E) facility, a scaled downcomer pipe installed in the PUMA-E SP, and air discharge pipe system. Two different diameter sizes of air injection pipe (0.076 and 0.102 m), a range of air volumetric flux (7.9–24.7 m/s), initial void conditions in an air injection pipe (fully void, partially void, and fully filled with water) and different air velocity ramp rates (1.0, 1.5, and 2.0 s) are used to investigate the impact of the blowdown conditions to the void distribution in the SP. Two distinct phases of experiments, namely, an initial and a quasi-steady phase were observed. The maximum void penetration depth was experienced during the initial phase. The quasi-steady phase provided less void

  2. JAERI's activities in JCO accident

    The Japan Atomic Energy Research Institute (JAERI) was actively involved in a variety of technical supports and cooperative activities, such as advice on terminating the criticality condition, contamination checks of the residents and consultation services for the residents, as emergency response actions to the criticality accident at the uranium processing facility operated by the JCO Co. Ltd., which occurred on September 30, 1999. These activities were carried out in collaborative ways by the JAERI staff from the Tokai Research Establishment, Naka Fusion Research Establishment, Oarai Research Establishment, and Headquarter Office in Tokyo. As well, the JAERI was engaged in the post-accident activities such as identification of accident causes, analyses of the criticality accident, and dose assessment of exposed residents, to support the Headquarter for Accident Countermeasures of the Science and Technology Agency (STA), the Accident Investigation Committee and the Health Control Committee of the Nuclear Safety Commission of Japan (NSC). This report compiles the activities, that the JAERI has conducted to date, including the discussions on measures for terminating the criticality condition, evaluation of the fission number, radiation monitoring in the environment, dose assessment, analyses of criticality dynamics. (author)

  3. The influence of accident measures on accident scenarios for VVER-1000-Type reactors

    For VVER-1000-type reactors severe accident scenarios and possible mitigation strategies are investigated. The Station blackout sequence is chosen as reference case. At first a comparison between the cases with and without working spray systems is discussed. Afterwards the results of a parametric study investigating the influence of different water volumes on the course of the accident are presented. It can be shown that most of these accident mitigation measures will maintain the containment integrity and reduce the source term. (author)

  4. 园内儿童意外伤害对托幼园所影响的调查分析%Investigation on the influence of children's accident on kindergartens

    袁全莲; 马迎华

    2012-01-01

    目的 了解海淀区园内儿童意外伤害对托幼园所影响的现状,为制定减少园内意外伤害发生及其对园所影响的有效干预措施提供依据.方法 针对海淀区2007至2009年发生的306例园内意外伤害对托幼园所的影响进行调查分析.结果 随着园所级别升高,发生意外伤害的园所数逐渐减少,各类园所间发生意外伤害的比例差异有统计学意义(χ2=29.49,P<0.05).3年中园所因意外伤害导致直接经济损失约22万元,占园所支付伤害处置费用的76.1%.意外伤害的发生对园所的正常工作、教师情绪及经济损失等的不良影响程度随园所级别的降低而升高.结论 加强托幼园所与家长的信息沟通,使家长充分理解托幼园所的工作,推广全面覆盖儿童的意外伤害保险,减少儿童意外伤害对园所的影响.%Objective To understand the current status of the influence of children' s accident in kindergartens of Haidian District on kindergartens, so as to provide scientific guideline for effective measures to decrease children' s accident in kindergartens and the influence on kindergartens. Methods Three hundred and six cases of children s accident happened from 2007 to 2009 and the influence on the kindergartens of Haidian District were investigated. Results The children s accident was less with the highering of kindergartens rank, and the difference in rate of accident in different kindergartens was statistically significant ( χ2 - 29. 49,P < 0. 05 ). In these three years about 220 thousands yuan was lost because of accident in kindergartens, which occupied 76. 1% of expense of injury. The negative effects of accident on normal work of kindergarten, teachers' mood and economic loss increased with the lowering of kindergartens' rank. Conclusion Enhancing communication between parents and kindergartens promotes parents full understanding of kindergartens daily work. Accident insurance for children needs to be promoted so

  5. SEVERE ACCIDENT MANAGEMENT TRAINING

    The purpose of this paper is (a) to define the International Atomic Energy Agency's role in the area of severe accident management training, (b) to briefly describe the status of representative severe accident analysis tools designed to support development and validation of accident management guidelines, and more recently, simulate the accident with sufficient accuracy to support the training of technical support and reactor operator staff, and (c) provide an overview of representative design-specific accident management guidelines and training. Since accident management and the development of accident management validation and training software is a rapidly evolving area, this paper is also intended to evolve as accident management guidelines and training programs are developed to meet different reactor design requirements and individual national requirements

  6. Perspective on post-Fukushima severe accident research

    After the Fukushima Daiichi accident in March 2011 several investigation committees issued reports with lessons learned from the accident, in which some recommendations on severe accident research are included. The review of specific severe accident research items had already started before Fukushima accident in working group of Atomic Energy Society of Japan (AESJ) in terms of significance of consequences, uncertainties of phenomena and maturity of assessment methodology. Re-investigation started after the Fukushima accident in this working group to cover additional effects of Fukushima accident, such as core degradation behaviors, sea water injection, containment failure/leakage and re-criticality. The review results are categorized in nine major fields; core degradation behavior, core melt coolability/retention in containment vessel, function of containment vessel, source term, hydrogen behavior, fuel-coolant interaction, molten core concrete interaction, recriticality and instrumentation in severe accident conditions. In January 2012, in collaboration with this working group, Research Expert Committee on Evaluation of Severe Accident was established in AESJ in order to investigate severe accident related issues for future LWR development. Based on these activities and also author's personal view, the present paper describes the seven important severe accident research issues after Fukushima accident. They are (1) investigation of damaged core and components, (2) advanced severe accident analysis capabilities and associated experimental investigations, (3) development of reliable passive cooling system for core/containment, (4) analysis of hydrogen behavior and investigation of hydrogen measures, (5) enhancement of removal function of radioactive materials of containment venting, (6) advanced instrumentation for the diagnosis of severe accident and (7) assessment of advanced containment design which exchides long-term evacuation in any severe accident situations

  7. Investigation of radiocesium distribution in organs of wild boar grown in Iitate, Fukushima after the Fukushima Daiichi nuclear power plant accident

    The concentrations of radiocesium in different organs of wild boar inhabiting Iitate, Fukushima were measured, after the Fukushima Daiichi nuclear power plant accident. After dissection, about 24 parts were collected and measured using a NaI gamma ray counter. In 2012, the radiocesium concentration (134Cs and 137Cs) was highest in muscle (approximately 15,000 Bq kg-1) and low in ovary, bone and thyroid gland, indicating large variation among tissues. Radiocesium concentrations in 24 different organs revealed the pattern of distribution of radiocesium in wild boar and indicated its availability in the ecosystem of the forests and villages where the boars matured. (author)

  8. Traffic Congestion and Accidents

    Schrage, Andrea

    2006-01-01

    Obstructions caused by accidents can trigger or exacerbate traffic congestion. This paper derives the efficient traffic pattern for a rush hour with congestion and accidents and the corresponding road toll. Compared to the model without accidents, where the toll equals external costs imposed on drivers using the road at the same time, a new insight arises: An optimal toll also internalizes the expected increase in future congestion costs. Since accidents affect more drivers if traffic volumes...

  9. Psychology of nuclear accidents

    Tysoe, M.

    1983-03-31

    Incidents involving nuclear weapons are described, as well as the accident to the Three Mile Island-2 reactor. Methods of assessment of risks are discussed, with particular reference to subjective judgements and the possible role of human error in civil nuclear accidents. Accidents or misunderstandings in communication or human actions which might lead to nuclear war are also discussed.

  10. Accident knowledge and emergency management

    The report contains an overall frame for transformation of knowledge and experience from risk analysis to emergency education. An accident model has been developed to describe the emergency situation. A key concept of this model is uncontrolled flow of energy (UFOE), essential elements are the state, location and movement of the energy (and mass). A UFOE can be considered as the driving force of an accident, e.g., an explosion, a fire, a release of heavy gases. As long as the energy is confined, i.e. the location and movement of the energy are under control, the situation is safe, but loss of confinement will create a hazardous situation that may develop into an accident. A domain model has been developed for representing accident and emergency scenarios occurring in society. The domain model uses three main categories: status, context and objectives. A domain is a group of activities with allied goals and elements and ten specific domains have been investigated: process plant, storage, nuclear power plant, energy distribution, marine transport of goods, marine transport of people, aviation, transport by road, transport by rail and natural disasters. Totally 25 accident cases were consulted and information was extracted for filling into the schematic representations with two to four cases pr. specific domain. (au) 41 tabs., 8 ills.; 79 refs

  11. The radiological accident in Cochabamba

    In April 2002 an accident involving an industrial radiography source containing 192Ir occurred in Cochabamba, Bolivia, some 400 km from the capital, La Paz. A faulty radiography source container had been sent back to the headquarters of the company concerned in La Paz together with other equipment as cargo on a passenger bus. This gave rise to a potential for serious exposure for the bus passengers as well as for the company employees who were using and transporting the source. The Government of Bolivia requested the assistance of the IAEA under the terms of the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency. The IAEA in response assembled and sent to Bolivia a team composed of senior radiation safety experts and radiation pathology experts from Brazil, the United Kingdom and the IAEA to investigate the accident. The IAEA is grateful to the Government of Bolivia for the opportunity to report on this accident in order to disseminate the valuable lessons learned and help prevent similar accidents in the future

  12. Accident knowledge and emergency management

    Rasmussen, B.; Groenberg, C.D.

    1997-03-01

    The report contains an overall frame for transformation of knowledge and experience from risk analysis to emergency education. An accident model has been developed to describe the emergency situation. A key concept of this model is uncontrolled flow of energy (UFOE), essential elements are the state, location and movement of the energy (and mass). A UFOE can be considered as the driving force of an accident, e.g., an explosion, a fire, a release of heavy gases. As long as the energy is confined, i.e. the location and movement of the energy are under control, the situation is safe, but loss of confinement will create a hazardous situation that may develop into an accident. A domain model has been developed for representing accident and emergency scenarios occurring in society. The domain model uses three main categories: status, context and objectives. A domain is a group of activities with allied goals and elements and ten specific domains have been investigated: process plant, storage, nuclear power plant, energy distribution, marine transport of goods, marine transport of people, aviation, transport by road, transport by rail and natural disasters. Totally 25 accident cases were consulted and information was extracted for filling into the schematic representations with two to four cases pr. specific domain. (au) 41 tabs., 8 ills.; 79 refs.

  13. Investigation of Local Effects Influence on Results of Design Basis Accident Analysis of WWER-440 Reactor Using RELAP5-3D Code

    One of the most important tasks in today's nuclear power plant safety analysis is a simulation of physical processes at nuclear facilities which accounts for 3-dimensional effects in the core and downcomer of reactor. System coupled thermo-hydraulic/neutron-kinetic code RELAP5-3D, which is a modeling tool provided to University of Kyiv by US DOE in a frame of International Nuclear Safety Program, allows simulation of variable in time spatial distribution of neutron flux in a core and also includes special components for 3D modeling of thermo-hydraulics. A model of Rivne NPP Unit 1 with WWER-440/V-213 type reactor has been developed for RELAP5-3D code. A scenario of 'Main steam line break' design basis accident has been calculated using this model. Such a problem can be characterized by intensive overcooling of a primary coolant in affected loop and, taking into account partial mixing of coolant from different primary loops, a non-uniform cooling of reactor core. Obtained results have been compared with the results obtained by model, which has been used at Design Based Accidents analysis, performed at specified unit.(author)

  14. Framework for accident management

    Accident management is an essential element of the Nuclear Regulatory Commission (NRC) Integration Plan for the closure of severe accident issues. This element will consolidate the results from other key elements; such as the Individual Plant Examination (IPE), the Containment Performance Improvement, and the Severe Accident Research Programs, in a form that can be used to enhance the safety programs for nuclear power plants. The NRC is currently conducting an Accident Management Program that is intended to aid in defining the scope and attributes of an accident management program for nuclear power plants. The accident management plan will ensure that a plant specific program is developed and implemented to promote the most effective use of available utility resources (people and hardware) to prevent and mitigate severe accidents. Hardware changes or other plant modifications to reduce the frequency of severe accidents are not a central aim of this program. To accomplish the outlined objectives, the NRC has developed an accident management framework that is comprised of five elements: (1) accident management strategies, (2) training, (3) guidance and computational aids, (4) instrumentation, and (5) delineation of decision making responsibilities. A process for the development of an accident management program has been identified using these NRC framework elements

  15. Severe Accident Research Program plan update

    In August 1989, the staff published NUREG-1365, ''Revised Severe Accident Research Program Plan.'' Since 1989, significant progress has been made in severe accident research to warrant an update to NUREG-1365. The staff has prepared this SARP Plan Update to: (1) Identify those issues that have been closed or are near completion, (2) Describe the progress in our understanding of important severe accident phenomena, (3) Define the long-term research that is directed at improving our understanding of severe accident phenomena and developing improved methods for assessing core melt progression, direct containment heating, and fuel-coolant interactions, and (4) Reflect the growing emphasis in two additional areas--advanced light water reactors, and support for the assessment of criteria for containment performance during severe accidents. The report describes recent major accomplishments in understanding the underlying phenomena that can occur during a severe accident. These include Mark I liner failure, severe accident scaling methodology, source term issues, core-concrete interactions, hydrogen transport and combustion, TMI-2 Vessel Investigation Project, and direct containment heating. The report also describes the major planned activities under the SARP over the next several years. These activities will focus on two phenomenological issues (core melt progression, and fuel-coolant interactions and debris coolability) that have significant uncertainties that impact our understanding and ability to predict severe accident phenomena and their effect on containment performance SARP will also focus on severe accident code development, assessment and validation. As the staff completes the research on severe accident issues that relate to current generation reactors, continued research will focus on efforts to independently evaluate the capability of new advanced light water reactor designs to withstand severe accidents

  16. JCO criticality accident termination operation

    In 2001, we summarized the circumstances surrounding termination of the JCO criticality accident based on testimony in the Mito District Court on December 17, 2001. JCO was the company for uranium fuels production in Japan. That document was assembled based on actual testimony in the belief that a description of the work involved in termination of the accident would be useful in some way for preventing nuclear disasters in the future. The description focuses on the witness' own behavior, and what he saw and heard, and thus is written from the perspective of action by one individual. This was done simply because it was easier for the witness to write down his memories as he remembers them. Description of the activities of other organizations and people is provided only as necessary, to ensure that consistency in the descriptive approach is not lost. The essentials of this report were rewritten as a third-person objective description in the summary of the report by the Atomic Energy Society of Japan (AESJ). Since then, comments have been received from sources such as former members of the Nuclear Safety Commission (Dr. Kenji Sumita and Dr. Akira Kanagawa), concerned parties from the former Science and Technology Agency, and reports from the JCO Criticality Accident Investigation Committee of the AESJ, and thus this report was rewritten to correct incorrect information, and add material where that was felt to be necessary. This year is the tenth year of the JCO criticality accident. To mark this occasion we have decided to translate the record of what occurred at the accident site into English so that more people can draw lessons from this accident. This report is an English version of JAEA-Technology 2009-073. (author)

  17. General Aspects of the JCO Criticality Accident

    A criticality accident occurred on September 30, 1999, at a uranium processing plant of JCO Company in Tokaimura. Delayed criticality continued for approximately 20 hours after the first few prompt critical peaks. Two employees subsequently died. Nearby residents were evacuated or told to remain indoors. This accident was at Level 4 on the International Nuclear Event Scale. A table of radiation exposures resulting from the accident is given. Besides dealing with health physics, the investigation committee's final report covered technical observations and the nature of the accident. The direct causes of the accident were found to be violation of rules and technical specifications and deviation from licensing conditions; some of these were permitted by the company itself, and fatal mistakes were made by employees on the job without consulting with authorized persons. Many recommendations to revise government regulations on licensing of nuclear fuel handling were discussed in the report

  18. Visualization of Traffic Accidents

    Wang, Jie; Shen, Yuzhong; Khattak, Asad

    2010-01-01

    Traffic accidents have tremendous impact on society. Annually approximately 6.4 million vehicle accidents are reported by police in the US and nearly half of them result in catastrophic injuries. Visualizations of traffic accidents using geographic information systems (GIS) greatly facilitate handling and analysis of traffic accidents in many aspects. Environmental Systems Research Institute (ESRI), Inc. is the world leader in GIS research and development. ArcGIS, a software package developed by ESRI, has the capabilities to display events associated with a road network, such as accident locations, and pavement quality. But when event locations related to a road network are processed, the existing algorithm used by ArcGIS does not utilize all the information related to the routes of the road network and produces erroneous visualization results of event locations. This software bug causes serious problems for applications in which accurate location information is critical for emergency responses, such as traffic accidents. This paper aims to address this problem and proposes an improved method that utilizes all relevant information of traffic accidents, namely, route number, direction, and mile post, and extracts correct event locations for accurate traffic accident visualization and analysis. The proposed method generates a new shape file for traffic accidents and displays them on top of the existing road network in ArcGIS. Visualization of traffic accidents along Hampton Roads Bridge Tunnel is included to demonstrate the effectiveness of the proposed method.

  19. Framework for accident management

    A program is being conducted to establish those attributes of a severe accident management plan which are necessary to assure effective response to all credible severe accidents and to develop guidance for their incorporation in a plant's Accident Management Plan. This program is one part of the Accident Management Research Program being conducted by the U. S. Nuclear Regulatory Commission (NRC). The approach used in establishing attributes and developing guidance includes three steps. In the first step the general attributes of an accident management plan were identified based on: (1) the objectives established for the NRC accident management program, (2) the elements of an accident management framework identified by the NRC, and (3) a review of the processes used in developing the currently used approach for classifying and analyzing accidents. For the second step, a process was defined that uses the general attributes identified from the first step to develop an accident management plan. The third step applied the process defined in the second step at a nuclear power plant to refine and develop it into a benchmark accident management plan. Step one is completed, step two is underway and step three has not yet begun

  20. Radiological accident 'The Citadel' medical aspects

    The work exposes the medical actions carried out in the mitigation of the consequences of the accident and its main results. In a facility of storage of radioactive waste in Caracas, Venezuela, it was happened a radiological accident. This event caused radioactive contamination of the environment, as well as the irradiation and radioactive contamination of at least 10 people involved in the fact, in its majority children. Cuban institutions participated in response to the accident. Among the decisions adopted by the team of combined work Cuban-Venezuelan, we find the one of transferring affected people to Cuba, for their dosimetric and medical evaluation. Being designed a work strategy to develop the investigations to people affected by the radiological accident, in correspondence with the circumstances, magnitude and consequences of the accident. The obtained main results are: 100% presented affectations in its health, not associate directly to the accident, although the accident influenced in its psychological state. In 3 of studied people they were detected radioactive contamination with Cesium -137 with dose among 2.01 X 10-4 Sv up to 2.78 X 10-4 Sv. This accident demonstrated the necessity to have technical capacities to face these events and the importance of the international solidarity. (author)

  1. Accidents, probabilities and consequences

    Following brief discussion of the safety of wind-driven power plants and solar power plants, some aspects of the safety of fast breeder and thermonuclear power plants are presented. It is pointed out that no safety evaluation of breeders comparable to the Rasmussen investigation has been carried out and that discussion of the safety aspects of thermonuclear power is only just begun. Finally, as an illustration of the varying interpretations of risk and safety analyses, four examples are given of predicted probabilities and consequences in Copenhagen of the maximum credible accident at the Barsebaeck plant, under the most unfavourable meterological conditions. These are made by the Environment Commission, Risoe Research Establishment, REO (a pro-nuclear group) and OOA (an anti-nuclear group), and vary by a factor of over 1000. (JIW)

  2. 四川保教人员儿童意外伤害救护培训情况调查%Investigation of Rescue Training on Children Accident Injuries among Child-care and Teaching Staff in Sichuan

    王威

    2016-01-01

    [目的]了解四川托幼机构工作人员儿童意外伤害救护的具体培训与培训需求情况,为开展幼儿教师急救知识与技能的培训提供参考建议。[方法]通过问卷调查法和访谈法在四川16个地区抽取499名保教人员进行儿童意外伤害救护培训情况调查。[结果]四川保教人员儿童意外伤害救护的总体培训率较高;公立幼儿园培训比例较私立幼儿园高;保教人员已参加的培训方式与期望参加的培训方式有一定差异;在编和高学历人员希望参加更多的高层次专业培训。[结论]幼儿园虽有培训需求,由于条件限制,模拟实训的机会不多,需教育行政部门和教师培训机构承担更多的实施、管理者角色。%Objective]To find out the specific trainings and the training needs for children accident injuries rescue among the staff in nurseries and kindergartens,and provide the suggestions for preschool teachers to carry out first-aid knowledge and skills training.[Methods]Questionnaire and interview methods were used for carrying out the rescue training investigations on children accident injuries among 499 child-care and teaching staff in 16 areas in Sichuan. [ Results]The overall rescue training rate on children accident injuries among the child-care and teaching staff in Sichuan is relatively higher;the training rate in public kindergartens is higher than that in pri-vate ones;differences exist between the attended training ways and the expected ones;teachers on payroll and with high-education hope to participate in higher -level professional training. [ Conclusion]Although kindergartens have the rescue training needs for children accident injuries,due to the limited situation the simulation training op-portunities are still few,which needs the education administrative department and teacher-training institutions to take more roles of implementation and management.

  3. The Chernobyl accident consequences

    Five teen years later, Tchernobyl remains the symbol of the greater industrial nuclear accident. To take stock on this accident, this paper proposes a chronology of the events and presents the opinion of many international and national organizations. It provides also web sites references concerning the environmental and sanitary consequences of the Tchernobyl accident, the economic actions and propositions for the nuclear safety improvement in the East Europe. (A.L.B.)

  4. Communication and industrial accidents

    As, Sicco van

    2001-01-01

    This paper deals with the influence of organizational communication on safety. Accidents are actually caused by individual mistakes. However the underlying causes of accidents are often organizational. As a link between these two levels - the organizational failures and mistakes - I suggest the concept of role distance, which emphasizes the organizational characteristics. The general hypothesis is that communication failures are a main cause of role distance and accident-proneness within orga...

  5. Laser accidents: Being Prepared

    Barat, K

    2003-01-24

    The goal of the Laser Safety Officer and any laser safety program is to prevent a laser accident from occurring, in particular an injury to a person's eyes. Most laser safety courses talk about laser accidents, causes, and types of injury. The purpose of this presentation is to present a plan for safety offices and users to follow in case of accident or injury from laser radiation.

  6. Lizimetric investigation of vertical transportation of Cs-137 in the different soil types for the different raining conditions: a new solution proposal and application for the Chernobyl accident

    driven from experiments which were reached by classical model calculations harmonies well with the present results. Although the present results and the conclusion reached by classical model calculations harmonies, it is observed that there are important differences between them. The vertical transportation in soil was slower in the present experiments than the classical model calculations. As a reason of this difference, it can be showed that the darcy speed which is an ideal speed for soil that is used in the classical model calculation, doesn't agree with the realistic speed that can be changing according to soil type and characteristics. In order to avoid the important differences between the classical model calculation and present experimental results, a new solution for the semi infinite convection diffusional model is proposed in the originality of this Ph.D. thesis. In this proposal of water which is taken by the darcy speed is decreased by a value of the ratio of the migration coefficient to the darcy speed. The result obtained by our new solution proposal agrees quite well with our experimental result. The results that are reached by new solution proposal for different soil types and every raining regimes are harmonies with the sequence of our experiment. Meanwhile the conclusion that is reached for the different raining regime and every soil type also harmonies with the experimental results. As a result the conclusion that is reached in new solution proposal is suitable as ones in the classical model calculations to the experiment. If we compare the results with the experimental ones, we see that our new solution agrees better than the classical model results. Therefore new solution proposal that is the originality of this Ph.D. thesis more realistic than the classical model. Moreover this proposed solution is used to examine a realistic applicational case, that is the of the nuclear reactor accident in Chernobyl in 26 April 1986 which was occurred in Ukraine

  7. Nuclear accidents and epidemiology

    A consultation on epidemiology related to the Chernobyl accident was held in Copenhagen in May 1987 as a basis for concerted action. This was followed by a joint IAEA/WHO workshop in Vienna, which reviewed appropriate methodologies for possible long-term effects of radiation following nuclear accidents. The reports of these two meetings are included in this volume, and cover the subjects: 1) Epidemiology related to the Chernobyl nuclear accident. 2) Appropriate methodologies for studying possible long-term effects of radiation on individuals exposed in a nuclear accident. Figs and tabs

  8. Standby after the Chernobyl accident

    The report is an investigation concerning strandby and actions by SKI (Swedish Nuclear Power Inspectorate) and SSI (National Institute of Radiation Protection) due to the Chernobyl reactor accident. It consists of a final report and two appendices. The final report is divided into two parts: 'I: Facts' and 'II: Analyzes'. 'Facts': The Swedish model for information: radio, press. Basic knowledge about ionizing radiation in the society. Resources for information. Need for information. Message forms for information. Announcements from the authorities in TV, radio, press, meeting, advertisements. Statements concerning the reactor accident and its consequences in Swedish mass media. How did the public recieve the information? 'Analyzis': Information responsibilities and policies. SSI information activities concerning radiologic accidents, conditions, methods and resources. Ditto for SKI, Swedish National Food Administration and the National Board of Agriculture. Appendix I: Information from authorities in the press three weeks after the Chernobyl accident: The material and the methods. The acute phase, the adoptation phase, the extension of the persective. What is said about the authorities in connection with Chernobyl? Appendix II: The fallout from Chernobyl, the authorities and the media coverage: The nationwide, regional and local coverage from radio and television. Ditto from the press. Topic and problem areas in reporting. Instructions from the authorities in media. Contribution in the media from people representing the authorities. Fallout in a chronologic perspective. (L.F.)

  9. Concerning the structure of occupational accidents involving construction workers in the erection of nuclear power plants

    An investigation of 561 occupational accidents involving construction workers which took place during the construction of nuclear power plants failed to show any significant deviation in comparison with general construction as regards process classification, classification of accidents according to occupation and situation, and accidents severity. Occupational accidents which are typial for nuclear power plant construction are a rare exception. (orig.)

  10. Experience and lessons learned from emergency disposal of Fukushima nuclear power station accident

    After Fukushima nuclear accident, we visited the related medical aid agencies for nuclear accidents and conducted investigations in disaster-affected areas in Japan. This article summarizes the problems with emergency disposal of Fukushima nuclear accident while disclosing problems should be solved during the emergency force construction for nuclear accidents. (authors)

  11. Stocks and energy shocks : the impact of energy accidents on stock market value

    Scholtens, B.; Boersen, A.

    2011-01-01

    We investigate how financial market participants value energy accidents. We employ an event study to look into the response of stock markets to 209 accidents. These accidents were derived from Sovacool's (2008) database on major energy accidents from 1907 to 2007. It appears that the stock market in

  12. Compilation of accident statistics in PSE

    The objective of the investigations on transportation carried out within the framework of the 'Project - Studies on Safety in Waste Management (PSE II)' is the determination of the risk of accidents in the transportation of radioactive materials by rail. The fault tree analysis is used for the determination of risks in the transportation system. This method offers a possibility for the determination of frequency and consequences of accidents which could lead to an unintended release of radionuclides. The study presented compiles all data obtained from the accident statistics of the Federal German Railways. (orig./RB)

  13. Analysis of the FPT-0, FPT-1 and FPT-2 experiments of the PHEBUS FP program investigating in-vessel phenomena during a LWR accidents

    This paper describes the results and the current status of the analysis of the core degradation aspects for the FPT0, FPT1 and FPT2 tests, using the mechanistic ICARE/CATHARE code system developed by IRSN 'Institut de Radioprotection et de Surete Nucleaire'. The objective of those experiments, in the framework of the International Phebus Fission Product program, was to get a significant FP release induced by fuel rod degradation and fuel melting in a prototypical way using real materials as present in a PWR fuel assembly. During the transient, most of the phenomena that could occur in-vessel during a PWR severe accident (thermo mechanical fuel rod rupture, absorber rod degradation, steam-zircaloy chemical reaction and hydrogen generation, fuel dissolution and molten pool formation) have been observed. They are quite well simulated with the ICARE2 V3mod1 code version, in particular the hydrogen generation. The experiments showed core degradation far beyond any other integral experiment (PBF SFD, Phebus-SFD, CORA, FLHT, and LOFT-FP-2). The severe damage observed in the bundle seems to be due to significant material interactions, initiated by structural materials possibly enhanced by the fuel swelling and fragmentation, and its changes in stoichiometry. The fuel burn-up and the oxygen potential during cladding oxidation are probably important factors. It was observed that fuel liquefaction and transition from rod like geometry to molten pool could occur at a temperature (2600+/-200K) largely below the actual melting point of the pure UO2 (3110K). Though the detailed modeling of such interactions has still to be improved, the ICARE2 code simulates fairly well the observed fuel degradation. The Phebus FP series of integral experiments have proved the capability of the program to significantly improve our understanding of the source term issue and important aspects of core degradation

  14. Radiation accident in Viet Nam

    In November 1992 a Vietnamese research physicist was working with a microtron accelerator when he received a radiation overexposure that required the subsequent amputation of his right hand. A team from the International Atomic Energy Agency visited Hanoi in March 1993 to carry out an investigation. It was concluded that the accident occurred primarily due to a lack of safety systems although the lack of both written procedures and training in basic radiation safety were also major contributors. (author)

  15. Criticality accident in Argentina

    A recent criticality type accident, ocurred in Argetina, is commented. Considerations about the nature of the facility where this accident took place, its genesis, type of operation carried out on the day of the event, and the medical aspects involved are done. (Author)

  16. Chernobyl accident and Danmark

    The report describes the Chernobyl accident and its consequences for Denmark in particular. It was commissioned by the Secretary of State for the Environment. Volume 1 contains copies of original documents issued by Danish authorities during the first accident phase and afterwards. Evaluations, monitoring data, press releases, legislation acts etc. are included. (author)

  17. Radiation accidents in hospitals

    Some of the radiation accidents that have occurred in Indian hospitals and causes that led to them are reviewed. Proper organization of radiation safety minimizes such accidents. It has been pointed out that there must be technical competence and mental preparedness to tackle emergencies when they do infrequently occur. (M.G.B.)

  18. Communication and industrial accidents

    As, Sicco van

    2001-01-01

    This paper deals with the influence of organizational communication on safety. Accidents are actually caused by individual mistakes. However the underlying causes of accidents are often organizational. As a link between these two levels - the organizational failures and mistakes - I suggest the conc

  19. Chernobyl accident and Denmark

    The report describes the Chernobyl accident and its consequences for Denmark in particular. It was commissioned by The Secretary of State for the Environment. Volume 2 contains copies of original documents issued by Danish authorities during the first accident phase and afterwards. Evaluations, monitoring data, press releases, legislation acts etc. are included. (author)

  20. Accidents with orphan sources

    The International Atomic Energy Agency has specifically defined statutory functions relating to the development of standards of safety and the provision for their application. It also has responsibilities placed on it by virtue of a number of Conventions, two of which are relevant to nuclear accidents or radiological emergencies - the Convention on Early Notification of a Nuclear Accident and the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency. An overview of the way in which these functions are being applied to prevent and respond to radiological accidents, particularly those involving orphan sources, is described in this paper. Summaries of a number of such accidents and of the Agency's Action Plan relating to the safety and security of radiation sources are given. (orig.)

  1. Consequences of radioactive releases into the sea resulting from the accident at the Fukushima Dai-ichi nuclear power plant - Evolution of expert investigation according to the data available

    The accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) in March 2011 led to an unprecedented direct input of artificial radioactivity into the marine environment. The Institute for Radioprotection and Nuclear Safety was requested by the French authorities to investigate the radioecological impact of this input, in particular the potential contamination of products of marine origin used for human consumption. This article describes the close link between the responses provided and the availability of the data, as well as their nature and ability to meet the requirements of expert investigation. These responses were needed: (i) to evaluate the inputs of radionuclides into the marine environment, (ii) to understand their dispersion in seawater, and (iii) to estimate their transfer to the biota and sediments. Three phases can be distinguished which characterise these processes during the accident and post-accident periods. The first phase corresponds to an emergency phase during which no measurements were available on samples from the marine environment. It involved the formulation of hypotheses based solely on the expertise of the Institute for Radioprotection and Nuclear Safety. The second phase started when the Japanese authorities provided measurements of the concentrations of radionuclides in seawater. Although these data were not yet adapted to addressing the problems of radioecology, the scenarios could then be refined and the estimates developed in more detail. During the third phase, the accumulation of data over the course of time made it possible to study the phenomena in an appropriate way. The chronology of the events shows that it is essential to have (i) significant measurements of concentration from samples collected in the various matrices of the marine environment, regularly updated and sufficiently well-documented, (ii) samples of seawater collected at the earliest opportunity as close as possible to the damaged site to characterise the

  2. Accident report 1975/76

    The statistics previously published on the development of accidents were completed. It is the purpose of this accident report: 1) to present a survey of the development of the number of accidents (no radiation accidents) for the years 1960 - 1976, 2) to break down the accidents by different characteristics in order to be able to recognize the preventive measures to be taken so as to avoid further accidents, 3) to report about accidents experienced and to indicate activities performed with respect to accident prevention and health protection. (orig.)

  3. Investigations on transient distribution of hydrogen and vapor in single spaces of the containment in case of high pressure failure of the reactor pressure vessel passing a core meltdown accident

    For the investigation of the sequences of a hypothetical core meltdown accident, the primary interest is directed towards the integrity of the containment. In case of insecurity, the valid interests become then the probable time period of failure and the type of failure of the containment (SB). Within the scope of investigations on possible loads exerted on containment during the process of core meltdown under high system pressure, the following question has to be answered. The question was whether an overlapping of the loads caused by possible local H2-burning or detonation occurred in addition to the loads (due to spontaneous release of mass and energy) exerted on the steel shell of the containment by the failure of primary circuit in the region of the bottom of the reactor pressure vessel (RPV). Therefore during the process of core meltdown after the failure the propagation behavior of stored masses of hydrogen in regions surrounding the reactor cavity was examined and the formed concentration ratios of hydrogen, steam and air at 22 different rooms during the transient relief phase were investigated. Under the assumption of homogeneous distribution of gaseous fractions in the individual rooms, no flammable gas mixtures were confirmed within the time range given for investigation. Therefore the load exerted following the spontaneous release of masses and energy due to failure of RPV (stem spike) cannot be overlapped with the same resulting due to process of H2-burning. (orig.)

  4. Accidents with sulfuric acid

    Rajković Miloš B.

    2006-01-01

    Full Text Available Sulfuric acid is an important industrial and strategic raw material, the production of which is developing on all continents, in many factories in the world and with an annual production of over 160 million tons. On the other hand, the production, transport and usage are very dangerous and demand measures of precaution because the consequences could be catastrophic, and not only at the local level where the accident would happen. Accidents that have been publicly recorded during the last eighteen years (from 1988 till the beginning of 2006 are analyzed in this paper. It is very alarming data that, according to all the recorded accidents, over 1.6 million tons of sulfuric acid were exuded. Although water transport is the safest (only 16.38% of the total amount of accidents in that way 98.88% of the total amount of sulfuric acid was exuded into the environment. Human factor was the common factor in all the accidents, whether there was enough control of the production process, of reservoirs or transportation tanks or the transport was done by inadequate (old tanks, or the accidents arose from human factor (inadequate speed, lock of caution etc. The fact is that huge energy, sacrifice and courage were involved in the recovery from accidents where rescue teams and fire brigades showed great courage to prevent real environmental catastrophes and very often they lost their lives during the events. So, the phrase that sulfuric acid is a real "environmental bomb" has become clearer.

  5. Persistence of airline accidents.

    Barros, Carlos Pestana; Faria, Joao Ricardo; Gil-Alana, Luis Alberiko

    2010-10-01

    This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non-stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long-run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation. PMID:20618386

  6. Management of severe accidents

    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)

  7. Accidents, risks and consequences

    Although the accident at Chernobyl can be considered as the worst accident in the world, it could have been worse. Other far worse situations are considered, such as a nuclear weapon hitting a nuclear reactor. Indeed the accident at Chernobyl is compared to a nuclear weapon. The consequences of Chernobyl in terms of radiation levels are discussed. Although it is believed that a similar accident could not occur in the United Kingdom, that possibility is considered. It is suggested that emergency plans should be made for just such an eventuality. Even if Chernobyl could not happen in the UK, the effects of accidents are international. The way in which nuclear reactor accidents happen is explored, taking the 1957 Windscale fire, Three Mile Island and Chernobyl as examples. Reactor designs and accident scenarios are considered. The different reactor designs are listed. As well as the Chernobyl RBMK design it is suggested that the light water reactors also have undesirable features from the point of view of safety. (U.K.)

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

    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 UO2–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

  9. Containment leakage during severe accident conditions

    An alternate to the THRESHOLD model used in most severe accident risk assessments has been investigated. One reference plant for each of six containment types has been studied to determine the magnitude of containment leakage that would result from the pressures and temperatures associated with severe accident conditions. Containment penetrations having the greatest potential for early containment leakage are identified. The studies indicate that containment leakage through penetrations prior to reaching containment threshold pressures (currently reported containment shell failure pressures) should be considered in severe accident risk assessments. Failure of non-metallic seals for containment penetrations can be a significant source of containment leakage under severe accident pressure and temperature conditions. Although studies of containment types are useful in identifying sources of containment leakage, final conclusions may need to be plant specific. Recommendations concerning future studies to better develop the use of continuous leakage models are provided. 9 references, 4 figures, 2 tables

  10. Consideration of severe accidents in design of advanced WWER reactors

    Severe accident related requirements formulated in General Regulations for Nuclear Power Plant Safety (OPB-88), in Nuclear Safety Regulations for Nuclear Power Stations' Reactor Plants (PBYa RU AS-89) and in other NPP nuclear and radiation guides of the Russian Gosatomnadzor are analyzed. In accordance with these guides analyses of beyond design basis accidents should be performed in the reactor plant design. Categorization of beyond design basis accidents leading to severe accidents should be made on occurrence probability and severity of consequences. Engineered features and measures intended for severe accident management should be provided in reactor plant design. Requirements for severe accident analyses and for development of measures for severe accident management are determined. Design philosophy and proposed engineered measures for mitigation of severe accidents and decrease of radiation releases are demonstrated using examples of large, WWER-1000 (V-392), and medium size WWER-640 (V-407) reactor plant designs. Mitigation of severe accidents and decrease of radiation releases are supposed to be conducted on basis of consistent realization of the defense in depth concept relating to application of a system of barriers on the path of spreading of ionizing radiation and radioactive materials to the environment and a set of engineered measures protecting these barriers and retaining their effectiveness. Status of fulfilled by OKB Gidropress and other Russian organizations experimental and analytical investigations of severe accident phenomena supporting design decisions and severe accident management procedures is described. Status of the works on retention of core melt inside the WWER-640 reactor vessel is also characterized