WorldWideScience

Sample records for accident conditions key

  1. Key Parameters for Operator Diagnosis of BWR Plant Condition during a Severe Accident

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, Dwight A [ORNL; Poore III, Willis P [ORNL

    2015-01-01

    The objective of this research is to examine the key information needed from nuclear power plant instrumentation to guide severe accident management and mitigation for boiling water reactor (BWR) designs (specifically, a BWR/4-Mark I), estimate environmental conditions that the instrumentation will experience during a severe accident, and identify potential gaps in existing instrumentation that may require further research and development. This report notes the key parameters that instrumentation needs to measure to help operators respond to severe accidents. A follow-up report will assess severe accident environmental conditions as estimated by severe accident simulation model analysis for a specific US BWR/4-Mark I plant for those instrumentation systems considered most important for accident management purposes.

  2. Key Characteristics of Combined Accident including TLOFW accident for PSA Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bo Gyung; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of); Yoon, Ho Joon [Khalifa University of Science, Technology and Research, Abu Dhabi (United Arab Emirates)

    2015-05-15

    The conventional PSA techniques cannot adequately evaluate all events. The conventional PSA models usually focus on single internal events such as DBAs, the external hazards such as fire, seismic. However, the Fukushima accident of Japan in 2011 reveals that very rare event is necessary to be considered in the PSA model to prevent the radioactive release to environment caused by poor treatment based on lack of the information, and to improve the emergency operation procedure. Especially, the results from PSA can be used to decision making for regulators. Moreover, designers can consider the weakness of plant safety based on the quantified results and understand accident sequence based on human actions and system availability. This study is for PSA modeling of combined accidents including total loss of feedwater (TLOFW) accident. The TLOFW accident is a representative accident involving the failure of cooling through secondary side. If the amount of heat transfer is not enough due to the failure of secondary side, the heat will be accumulated to the primary side by continuous core decay heat. Transients with loss of feedwater include total loss of feedwater accident, loss of condenser vacuum accident, and closure of all MSIVs. When residual heat removal by the secondary side is terminated, the safety injection into the RCS with direct primary depressurization would provide alternative heat removal. This operation is called feed and bleed (F and B) operation. Combined accidents including TLOFW accident are very rare event and partially considered in conventional PSA model. Since the necessity of F and B operation is related to plant conditions, the PSA modeling for combined accidents including TLOFW accident is necessary to identify the design and operational vulnerabilities.The PSA is significant to assess the risk of NPPs, and to identify the design and operational vulnerabilities. Even though the combined accident is very rare event, the consequence of combined

  3. Study on accident response robot for nuclear power plant and analysis of key technologies

    International Nuclear Information System (INIS)

    With the rapid development of nuclear power industry and improving demand for nuclear safety, the demand for developing accident response robot in nuclear power plant is increasingly urgent. Firstly, design analysis for accident response robot is taken with environmental conditions in nuclear power plant. Secondly, development for response robots after Chernobyl, JCO and Fukushima accidents are reviewed, and improvements for commercial mobile robot for use in radioactive environments are summarized. Finally, some key technologies including radiation-tolerance and system reliability are analyzed in details. (authors)

  4. ACCOUNT OF ROAD CONDITIONS WHILE INVESTIGATING TRAFFIC ACCIDENTS

    OpenAIRE

    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.

  5. Network conditioning under conflicting goals: Accident causation

    International Nuclear Information System (INIS)

    Networks based on the Barto-Sutton architecture (BSA) of neural-like elements have an information-processing structure that is analogous to the cognitive structure of a human. Given a set of explicitly stated rules of conduct, such networks develop a set of skills that is capable of satisfying the rules. In this sense, the network acts as a translator of rules into skill-based behavior. The BSA acquires its skills through casual, correlation-based scheduling. Stated briefly, it first constructs an internal representation, or model, of the rules of conduct, and then uses the model to correct deficiencies in its skill. It learns in a manner that closely resembles classical conditioning, shifting the onset of signals associated with unconditioned stimuli forward in time to coincide with the onset of conditioning stimuli. The low-level positive reinforcement the network receives from enhancing its operational efficiency is immediate and direct. In the absence of countervailing influences, this continuous pressure is sufficient to discount the recollection of past failures and leads to accidents with a predictable regularity

  6. Primary pump vibration under accident conditions

    International Nuclear Information System (INIS)

    This report presents the results of an international survey on the subject of vibration in nuclear primary coolant pumps due to two-phase flow, accident conditions. The literature search also revealed few Canadian references other than those of Ontario Hydro. Ontario Hydro's work has been extensive. Confidence in the mechanical integrity of the pumpsets is good, given the extent of the testing. However, conclusions with respect to piping integrity and thermal-hydraulic performance are difficult to determine due to the inexact geometry of the piping and the difficulties in estimating fluid conditions at the pump. The tests help to understand the phenomena and provide background information for analysis, but should be applied with caution to plant analyses. Much of the discussion in the report relates to pump head instability. This is perceived to be the most important flow regime causing vibration, as attested by the emphasis of the reviewed literature. A method for quantitative assessment of the forcing functions acting on the pump-piping system due to void generation and collapse is recommended. A relatively fundamental analytical approach is proposed, supplemented by reduced scale testing in the latter stages. 151 refs

  7. Using modular neural networks to monitor accident conditions in nuclear power plants

    International Nuclear Information System (INIS)

    Nuclear power plants are very complex systems. The diagnoses of transients or accident conditions is very difficult because a large amount of information, which is often noisy, or intermittent, or even incomplete, need to be processed in real time. To demonstrate their potential application to nuclear power plants, neural networks axe used to monitor the accident scenarios simulated by the training simulator of TVA's Watts Bar Nuclear Power Plant. A self-organization network is used to compress original data to reduce the total number of training patterns. Different accident scenarios are closely related to different key parameters which distinguish one accident scenario from another. Therefore, the accident scenarios can be monitored by a set of small size neural networks, called modular networks, each one of which monitors only one assigned accident scenario, to obtain fast training and recall. Sensitivity analysis is applied to select proper input variables for modular networks

  8. A radioactive waste transportation package monitoring system for normal transport and accident emergency response conditions

    International Nuclear Information System (INIS)

    This paper addresses spent fuel and high level waste transportation history and prospects, discusses accident histories of radioactive material transport, discusses emergency responder needs and provides a general description of the Transportation Intelligent Monitoring System (TRANSIMS) design. The key objectives of the monitoring system are twofold: (1) to facilitate effective emergency response to accidents involving a radioactive waste transportation package, while minimizing risk to the public and emergency first-response personnel, and (2) to allow remote monitoring of transportation vehicle and payload conditions to enable research into radioactive material transportation for normal and accident conditions. (J.P.N.)

  9. ACCOUNT OF ROAD CONDITIONS WHILE INVESTIGATING TRAFFIC ACCIDENTS

    Directory of Open Access Journals (Sweden)

    D. D. Selioukov

    2010-01-01

    Full Text Available 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.

  10. Development of solution behavior observation system under criticality accident conditions

    International Nuclear Information System (INIS)

    A solution behavior observation system was developed for observing the behavior of fissile solution and radiolytic voids under criticality accident conditions in TRACY. The system consisted of a radiation-resistive optical fiberscope and a CCD color video camera. The system functioned properly in the mixed high radiation fields of gamma rays and neutrons under criticality accident conditions, and it succeeded in taking the images of their behavior. They provide an important information to understand phenomena of fuel solution at criticality accidents and to construct computational kinetic models. The images can also be used as teaching materials for plant workers and students in universities. (author)

  11. Graphite Oxidation Simulation in HTR Accident Conditions

    Energy Technology Data Exchange (ETDEWEB)

    El-Genk, Mohamed

    2012-10-19

    Massive air and water ingress, following a pipe break or leak in steam-generator tubes, is a design-basis accident for high-temperature reactors (HTRs). Analysis of these accidents in both prismatic and pebble bed HTRs requires state-of-the-art capability for predictions of: 1) oxidation kinetics, 2) air helium gas mixture stratification and diffusion into the core following the depressurization, 3) transport of multi-species gas mixture, and 4) graphite corrosion. This project will develop a multi-dimensional, comprehensive oxidation kinetics model of graphite in HTRs, with diverse capabilities for handling different flow regimes. The chemical kinetics/multi-species transport model for graphite burning and oxidation will account for temperature-related changes in the properties of graphite, oxidants (O2, H2O, CO), reaction products (CO, CO2, H2, CH4) and other gases in the mixture (He and N2). The model will treat the oxidation and corrosion of graphite in geometries representative of HTR core component at temperatures of 900°C or higher. The developed chemical reaction kinetics model will be user-friendly for coupling to full core analysis codes such as MELCOR and RELAP, as well as computational fluid dynamics (CFD) codes such as CD-adapco. The research team will solve governing equations for the multi-dimensional flow and the chemical reactions and kinetics using Simulink, an extension of the MATLAB solver, and will validate and benchmark the model's predictions using reported experimental data. Researchers will develop an interface to couple the validated model to a commercially available CFD fluid flow and thermal-hydraulic model of the reactor , and will perform a simulation of a pipe break in a prismatic core HTR, with the potential for future application to a pebble-bed type HTR.

  12. Evaluation of current regulations and real accident conditions

    International Nuclear Information System (INIS)

    In order to improve estimates of the effectiveness of current regulatory standards, a program was initiated by the US Nuclear Regulatory Commission (NRC) to have the Lawrence Livermore Laboratory (LLNL) evaluate regulatory standards against real world accident conditions. This paper presents the results of the evaluation performed for the hypothetical 30-foot drop onto an unyielding surface and real world impact conditions which might be experienced by a spent fuel cask being transported by a truck. The results of the evaluations performed for other pertinent accident conditions for truck and train transport will be documented at the conclusion of the program. 10 refs., 8 figs., 3 tabs

  13. Accident management advisor system (AMAS): A Decision Aid for Interpreting Instrument Information and Managing Accident Conditions in Nuclear Power Plants

    International Nuclear Information System (INIS)

    for the development of models specifically tailored to real-time accident management. While it is almost impossible to develop and utilize exact models of the evolution of all possible accident sequences for each given type of nuclear power plant and containment design (e.g., PWR and BWR designs at various power ratings, large dry containment or ice condenser types, etc.), it appears possible to develop a sound approach to monitor the progression of an accident with respect to the integrity and effectiveness of a set of principal safety functions. The key to doing this is the development of a knowledge base 'housing structure', where uncertain knowledge regarding the predicted plant behavior and real-time, but also uncertain, information compiled from plant instrumentation readings can be compared and matched to produce the best possible identification of plant states and possible accident control actions. In summary: This paper illustrates the concept and the architecture of the Accident Management Advisor System, a decision aid which enables the use of combined instrument information to reduce uncertainty in decision making associated with nuclear plant accident conditions. The principal benefits offered by this concept are the definition of an approach to utilize instrument information under uncertain accident conditions in such a way as to allow the best possible assessment of plant status and the implementation of a formalized accident management decision-making strategy by means of a computer-based operator assistance tool. When fully developed, we expect AMAS to find application in both the commercial and government sections of the U.S. nuclear industry. We currently plan to have a working prototype of the system, ready to demonstrate its functionality for a representative commercial PWR plant, by the end of the next phase of our research, in which both model development and software development activities will have to be carried out. Finally, the AMAS

  14. Radionuclides release possibility analysis of MSR at various accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Choong Wie; Kim, Hee Reyoung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    There are some accidents which go beyond our expectation such as Fukushima Daiichi nuclear disaster and amounts of radionuclides release to environment, so more effort and research are conducted to prevent it. MSR (Molten Salt Reactor) is one of GEN-IV reactor types, and its coolant and fuel are mixtures of molten salt. MSR has a schematic like figure 1 and it has different features with the solid fuel reactor, but most important and interesting feature of MSR is its many safety systems. For example, MSR has a large negative void coefficient. Even though power increases, the reactor slows down soon. Radionuclides release possibility of MSR was analyzed at various accident conditions including Chernobyl and Fukushima ones. The MSR was understood to prevent the severe accident by the negative reactivity coefficient and the absence of explosive material such as water at the Chernobyl disaster condition. It was expected to contain fuel salts in the reactor building and not to release radionuclides into environment even if the primary system could be ruptured or broken and fuel salts would be leaked at the Fukushima Daiichi nuclear disaster condition of earthquake and tsunami. The MSR, which would not lead to the severe accident and therefore prevents the fuel release to the environment at many expected scenarios, was thought to have priority in the aspect of accidents. A quantitative analysis and a further research are needed to evaluate the possibility of radionuclide release to the environment at the various accident conditions based on the simple comparison of the safety feature between MSR and solid fuel reactor.

  15. Countermeasures for traffic accidents due to road conditions in China

    Institute of Scientific and Technical Information of China (English)

    PEI Yu-long; MA Ji

    2005-01-01

    Regarding the postulate of traffic infrastmcture and vehicles, much attention should be given to the effect of road conditions on accidents. With large numbers of traffic accidents on Shenda Freeway, Liaoning Province, Harbin City and others in P. R. China, parameters and the effect of accidents caused by horizontal alignment, vertical alignment, cross section and intersection are studied systematically The disciplinary analysis of these effects are presented in this paper. The viewpoint is acknowledged that high sub grade and steep slopes are against traffic safety, which is common and ignored in high-usage highways in China. Design parameters of the current design criteria and the corresponding countermeasures are suggested for safety on our highways.

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-03-01

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

  18. Investigations on pressure suppression system loads at accident conditions

    International Nuclear Information System (INIS)

    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.)

  19. Dynamic response of MARS reactor under design basis accident conditions

    International Nuclear Information System (INIS)

    The 600 MWth MARS (Multipurpose Advanced Reactor Inherently Safe) one single loop reactor for electric power and/or industrial heat generation relies on a totally inherent and passive safety concept. The key issue of residual heat evacuation in case of accident is solved through a completely passive Emergency Core Cooling System (ECCS) which consists of two independent circuits based on natural circulation triggered by passive check valves activated by the primary pump trip. In principle such a scheme for the decay heat removal system provides for an infinite cooling capability and no man intervention is required. In case of accident the ECCS is activated by the primary pump trip and after a first transient phase, the natural forcing head assures natural convection in the ECCS. The accident analysis related to those design basis events such as Station Blackout, Steam Line Break and Steam Generator Tube Rupture, demonstrates that thanks to its inherent and passive safety features, the reactor is always correctly cooled within the required safety limits. The results evidentiate that the ECCS intervenes in a relatively short time and provides adequate coolant flow rates so that no damage to the fuel and core structures is to be expected. Even in the residual case of lack of both air condensers in the ECCS, the about 100 hours grace period' provided by the water reserve stored in the pool, reasonably allows for undertaking the most appropriate countermeasures. (author)

  20. Predictions of structural integrity of steam generator tubes under normal operating, accident, an severe accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Majumdar, S. [Argonne National Lab., IL (United States)

    1997-02-01

    Available models for predicting failure of flawed and unflawed steam generator tubes under normal operating, accident, and severe accident conditions are reviewed. Tests conducted in the past, though limited, tended to show that the earlier flow-stress model for part-through-wall axial cracks overestimated the damaging influence of deep cracks. This observation was confirmed by further tests at high temperatures, as well as by finite-element analysis. A modified correlation for deep cracks can correct this shortcoming of the model. Recent tests have shown that lateral restraint can significantly increase the failure pressure of tubes with unsymmetrical circumferential cracks. This observation was confirmed by finite-element analysis. The rate-independent flow stress models that are successful at low temperatures cannot predict the rate-sensitive failure behavior of steam generator tubes at high temperatures. Therefore, a creep rupture model for predicting failure was developed and validated by tests under various temperature and pressure loadings that can occur during postulated severe accidents.

  1. On the removal of airborne particulate radioactivity under accident conditions

    International Nuclear Information System (INIS)

    In the case of an accident, the filter elements in the ventilation systems of a nuclear facility may become a part of the remaining fission product barrier. Within the framework of the Project Nuclear Safety of the Karlsruhe Nuclear Research Center, contributions are made to an increase in reliability of the air cleaning systems under accident conditions. These include the development and verification of computer programs for the estimation of those conditions prevailing inside the air cleaning systems in the case of an accident. Experimental investigations into the response of HEPA filters to differential pressures involving both dry and moist air have demonstrated the occurence of structural failures with subsequent loss of efficiency at relatively low values of differential pressures. With regard to further investigations, a new test facility was put into operation for the realization of superimposed challenges. A new method for testing particulate removal efficiency under high temperature or high humidity was developed. Finally, first results of code development work and of the corresponding verification experiments are reported on. (orig.)

  2. Investigation of air cleaning system response to accident conditions

    International Nuclear Information System (INIS)

    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

  3. Numerical Study of Severe Accidents on Containment Venting Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Na Rae; Bang, Young Suk; Park, Tong Kyu; Lee, Doo Yong [FNC Technology Co., Yongin (Korea, Republic of); Choi, Yu Jung; Lee, Sang Won; Kim, Hyeong Taek [KHNP-CRI, Daejeon (Korea, Republic of)

    2014-10-15

    Under severe accident, the containment integrity can be challenged due to over-pressurization by steam and non-condensable gas generation. According to Seismic Probabilistic Safety Assessment (PSA) result, the late containment failure by over-pressurization has been identified as the most probable containment failure mode. In addition, the analyses of Fukushima nuclear power plant accident reveal the necessity of the proper containment depressurization to prevent the large release of the radionuclide to environment. Containment venting has been considered as an effective approach to maintain the containment integrity from over-pressurization. Basic idea of containment venting is to relieve the pressure inside of the containment by establishing a flow path to the external environment. To ensure the containment integrity under over-pressure conditions, it is crucial to conduct the containment vent in a timely manner with a sufficient discharge flow rate. It is also important to optimize the vent line size to prevent additional risk of leakage and to install at the site with limited space availability. The purpose of this study is to identify the effective venting conditions for preventing the containment over-pressurization and investigate the vent flow characteristics to minimize the consequence of the containment ventilation.. In order that, thermodynamic behavior of the containment and the discharged flow depending on different vent strategies are analyzed and compared. The representative accident scenarios are identified by reviewing the Level 2 PSA result and the sensitivity analyses with varying conditions (i.e. vent line size and vent initiation pressure) are conducted. MAAP5 model for the OPR1000 Korea nuclear power plant has been used for severe accident simulations. Containment venting can be an effective strategy to prevent the significant failure of the containment due to over-pressurization. However, it should be carefully conducted because the vented

  4. Numerical Study of Severe Accidents on Containment Venting Conditions

    International Nuclear Information System (INIS)

    Under severe accident, the containment integrity can be challenged due to over-pressurization by steam and non-condensable gas generation. According to Seismic Probabilistic Safety Assessment (PSA) result, the late containment failure by over-pressurization has been identified as the most probable containment failure mode. In addition, the analyses of Fukushima nuclear power plant accident reveal the necessity of the proper containment depressurization to prevent the large release of the radionuclide to environment. Containment venting has been considered as an effective approach to maintain the containment integrity from over-pressurization. Basic idea of containment venting is to relieve the pressure inside of the containment by establishing a flow path to the external environment. To ensure the containment integrity under over-pressure conditions, it is crucial to conduct the containment vent in a timely manner with a sufficient discharge flow rate. It is also important to optimize the vent line size to prevent additional risk of leakage and to install at the site with limited space availability. The purpose of this study is to identify the effective venting conditions for preventing the containment over-pressurization and investigate the vent flow characteristics to minimize the consequence of the containment ventilation.. In order that, thermodynamic behavior of the containment and the discharged flow depending on different vent strategies are analyzed and compared. The representative accident scenarios are identified by reviewing the Level 2 PSA result and the sensitivity analyses with varying conditions (i.e. vent line size and vent initiation pressure) are conducted. MAAP5 model for the OPR1000 Korea nuclear power plant has been used for severe accident simulations. Containment venting can be an effective strategy to prevent the significant failure of the containment due to over-pressurization. However, it should be carefully conducted because the vented

  5. Methyl Iodide Formation Under Postulated Nuclear Reactor Accident Conditions

    International Nuclear Information System (INIS)

    The formation of methyl iodide under conditions of postulated nuclear reactor accidents is discussed. Although thermodynamic calculations indicate the equilibrium methyl iodide concentrations would be quite low, calculations based on a simple kinetic scheme involving reaction between small hydrocarbon species and iodine indicate that concentrations higher than equilibrium can occur during the course of the reaction. Such calculations were performed over a wide range of initial species concentrations and a range of temperatures representative of some reactor accident situations. These calculations suggest that little methyl iodide would be expected within the core volume where temperatures are maximum. As the gas leaves the core volume and expands into the plenum region, it cools and the concentration of methyl iodide increases. At the intermediate temperatures which might characterize this region, the formation of methyl iodide from thermally induced reactions could reach its maximum rate. The gas continues to cool, however, and it is probable that by the time it leaves the plenum region it has cooled to the point where thermally induced reactions may be of little importance. Although the thermally induced reactions will become slower as the gas expands and cools, the radiation-induced reactions will not be slowed to the same extent. The gases leaving the core carry fission products and hence a radiation source is available to initiate reaction by a temperature-independent process. An investigation of the radiation chemical formation and decomposition of methyl iodide in the presence of steam suggests that radiation-induced methyl iodide formation will generally be rapid under the postulated accident situations. Thus, in the plenum region where thermal reactions have become slow, the radiation-induced reaction can still proceed and may well become the dominant factor. The same situation probably pertains as well to the containment region. (author)

  6. The behaviour of radioactive waste packages under fire accident conditions

    International Nuclear Information System (INIS)

    An experimental study has been made of the behaviour of packaged Intermediate Level Wastes (ILW) subjected to heat. The conditions used represented fire accidents in the transport of the ILW to the repository in shielded transport containers and in the handling of the packages at the repository. The behaviour of four waste materials immobilised in cement and organic resin were studied. Each waste used had features which allowed the results to be applied to a wide range of other waste streams. Samples of these materials have been heated under controlled and well instrumented conditions in furnaces and pool fires. Inactive simulant wastes were used in small and full scale experiments. Fully active waste materials were used in small scale experiments only. Data are presented on the temperature profiles through the packaged ILW and on the release of volatile and particulate materials as a function of time and temperature. (orig.)

  7. On requirements to environment protection under accident conditions

    International Nuclear Information System (INIS)

    Accident situation on nuclear power plant operation is considered. Definition is given of the concept of ''Accident situation'' and recommendations are made for sequence of evaluation of such a situation. Population protection measures at an accident situation are considered depended on the level of radiation hazard. Recommendations are made for functions of accident team emergency evaluation of radiation hazard in the case of accident and recommendations on composition of equipment for mobile field dosimetric groups are also done. Requirements are given for emergency measures plan for nuclear power plant and criterions for radiation hazard estimation

  8. ORNL studies of fission product release under LWR accident conditions

    International Nuclear Information System (INIS)

    High burnup Zircaloy-clad UO2 fuel specimens have been heated to study the release of fission products in tests simulating LWR accident conditions. The dominant variable was found to be temperature, with atmosphere, time, and burnup also being significant variables. Comparison of data from tests in steam and hydrogen, at temperatures of 2000 to 2700 K, have shown that the releases of the most volatile species (Kr, Xe, I, and Cs) are relatively insensitive to atmosphere. The releases of the less-volatile species (Sr, Mo, Ru, Sb, Te, Ba, and Eu), however, may vary by orders of magnitude depending on atmosphere. In addition, the atmosphere may drastically affect the mode and extent of fuel destruction

  9. Ruthenium behaviour in severe nuclear accident conditions. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Backman, U.; Lipponen, M.; Auvinen, A.; Jokiniemi, J.; Zilliacus, R. [VVT Processes (Finland)

    2004-08-01

    During routine nuclear reactor operations, ruthenium will accumulate in the fuel in relatively high concentrations. In a steam atmosphere, ruthenium is not volatile, and it is not likely to be released from the fuel. However, in an air ingress accident during reactor power operation or during maintenance, ruthenium may form volatile species, which may be released into the containment. Oxide forms of ruthenium are more volatile than the metallic form. Radiotoxicity of ruthenium is high both in the short and the long term. The results of this project imply that in oxidising conditions during nuclear reactor core degradation, ruthenium release increases as oxidised gaseous species Ru03 and Ru04 are formed. A significant part of the released ruthenium is then deposited on reactor coolant system piping. However, in the presence of steam and aerosol particles, a substantial amount of ruthenium may be released as gaseous Ru04 into the containment atmosphere. (au)

  10. Comparison of selected U.S. highway and railway severe accidents to U.S. regulatory accident conditions and IAEA transport standards

    International Nuclear Information System (INIS)

    This paper discusses selected severe historical US highway and rail accidents and compares the mechanical and/or thermal environments associated with these accidents to the 10CFR71 Hypothetical Accident Conditions and the accident environments (both regulatory and extraregulatory) investigated in 'Shipping Container Response to Severe Highway and Railway Accident Conditions', which is commonly known as the Modal Study, and in 'Re-examination of Spent Fuel Shipment Risk Estimates', NUREG/CR-6672. Since the hypothetical accident conditions of 10CFR71 are similar to the International Atomic Energy Agency's (IAEA) package tests for accident conditions of transport, the evaluation is also valid in demonstrating the adequacy of IAEA's transport safety standard. Careful examination of the reports on the severe accidents revealed the accidents were found to be bounded by the regulatory environment described in 10CFR71. (author)

  11. Electrical equipment performance under severe accident conditions (BWR/Mark 1 plant analysis): Summary report

    International Nuclear Information System (INIS)

    The purpose of the Performance Evaluation of Electrical Equipment during Severe Accident States Program is to determine the performance of electrical equipment, important to safety, under severe accident conditions. In FY85, a method was devised to identify important electrical equipment and the severe accident environments in which the equipment was likely to fail. This method was used to evaluate the equipment and severe accident environments for Browns Ferry Unit 1, a BWR/Mark I. Following this work, a test plan was written in FY86 to experimentally determine the performance of one selected component to two severe accident environments

  12. A risk-based evaluation of the impact of key uncertainties on the prediction of severe accident source terms - STU

    International Nuclear Information System (INIS)

    The purpose of this project is to address the key uncertainties associated with a number of fission product release and transport phenomena in a wider context and to assess their relevance to key severe accident sequences. This project is a wide-based analysis involving eight reactor designs that are representative of the reactors currently operating in the European Union (EU). In total, 20 accident sequences covering a wide range of conditions have been chosen to provide the basis for sensitivity studies. The appraisal is achieved through a systematic risk-based framework developed within this project. Specifically, this is a quantitative interpretation of the sensitivity calculations on the basis of 'significance indicators', applied above defined threshold values. These threshold values represent a good surrogate for 'large release', which is defined in a number of EU countries. In addition, the results are placed in the context of in-containment source term limits, for advanced light water reactor designs, as defined by international guidelines. Overall, despite the phenomenological uncertainties, the predicted source terms (both into the containment, and subsequently, into the environment) do not display a high degree of sensitivity to the individual fission product issues addressed in this project. This is due, mainly, to the substantial capacity for the attenuation of airborne fission products by the designed safety provisions and the natural fission product retention mechanisms within the containment

  13. Identification of traffic accident risk-prone areas under low lighting conditions

    OpenAIRE

    K. Ivan; I. HAIDU; J. BENEDEK; Ciobanu, S. M.

    2015-01-01

    Besides other non-behavioural factors, the low lighting conditions significantly influence the frequency of the traffic accidents in the urban environment. This paper intends to identify the impact of low lighting conditions on the traffic accidents in the city of Cluj-Napoca. The dependence degree between lighting and the number of traffic accidents was analyzed by the Pearson's correlation and the relation between the spatial distributio...

  14. Shipping container response to severe highway and railway accident conditions: Main report

    International Nuclear Information System (INIS)

    This report describes a study performed by the Lawrence Livermore National Laboratory to evaluate the level of safety provided under severe accident conditions during the shipment of spent fuel from nuclear power reactors. The evaluation is performed using data from real accident histories and using representative truck and rail cask models that likely meet 10 CFR 71 regulations. The responses of the representative casks are calculated for structural and thermal loads generated by severe highway and railway accident conditions. The cask responses are compared with those responses calculated for the 10 CFR 71 hypothetical accident conditions. By comparing the responses it is determined that most highway and railway accident conditions fall within the 10 CFR 71 hypothetical accident conditions. For those accidents that have higher responses, the probabilities anf potential radiation exposures of the accidents are compared with those identified by the assessments made in the ''Final Environmental Statement on the Transportation of Radioactive Material by Air and other Modes,'' NUREG-0170. Based on this comparison, it is concluded that the radiological risks from spent fuel under severe highway and railway accident conditions as derived in this study are less than risks previously estimated in the NUREG-0170 document

  15. Large-Scale Containment Cooler Performance Experiments under Accident Conditions

    Directory of Open Access Journals (Sweden)

    Ralf Kapulla

    2012-01-01

    Full Text Available Computational Fluid Dynamics codes are increasingly used to simulate containment conditions after various transient accident scenarios. This paper presents validation experiments, conducted in the frame of the OECD/SETH-2 project. These experiments address the combined effects of mass sources and heat sinks related to gas mixing and hydrogen transport within containment compartments. A wall jet interacts with an operating containment cooler located in the middle (M-configuration and the top (T-configuration of the containment vessel. The experiments are characterized by a 3-phase injection scenario. In Phase I, pure steam is injected, while in Phase II, a helium-steam mixture is injected. Finally, in Phase III, pure steam is injected again. Results for the M-configuration show helium stratification build up during Phase II. During Phase III, a positively buoyant plume emerging from the cooler housing becomes negatively buoyant once it reaches the helium-steam layer and continuously erodes the layer. For the M-configuration, a strong degradation of the cooler performance was observed during the injection of the helium/steam mixture (Phase II. For the T-configuration, we observe a mainly downwards acting cooler resulting in a combination of forced and natural convection flow patterns. The cooler performance degradation was much weaker compared with the M-configuration and a good mixing was ensured by the operation of the cooler.

  16. Should evacuation conditions after a nuclear accident be revised?

    International Nuclear Information System (INIS)

    The author proposes to draw lessons from the Fukushima accident, notably in the field of post-accident management. He discusses the definition of an as widely understandable as possible method of description of risks related to irradiations after a nuclear accident. As these irradiations are mainly low dose ones which have a carcinogenic effect, he proposes to assess the average life expectancy loss due to an irradiation. Then, this risk can be easily compared with other risks like air pollution, smoking and passive smoking, and so on. Then, once this risk assessment method is well defined, it is possible to associate the inhabitants of contaminated areas to the post-accident management. They could then decide to go back to their homes or not with full knowledge of the facts

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

    OpenAIRE

    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 ...

  18. Identification of traffic accident risk-prone areas under low lighting conditions

    Directory of Open Access Journals (Sweden)

    K. Ivan

    2015-02-01

    Full Text Available Besides other non-behavioural factors, the low lighting conditions significantly influence the frequency of the traffic accidents in the urban environment. This paper intends to identify the impact of low lighting conditions on the traffic accidents in the city of Cluj-Napoca. The dependence degree between lighting and the number of traffic accidents was analyzed by the Pearson's correlation and the relation between the spatial distribution of traffic accidents and the lighting conditions was determined by the frequency ratio model. The vulnerable areas within the city were identified based on the calculation of the injured persons rate for the 0.5 km2 equally-sized areas uniformly distributed within the study area. The results have shown a strong linear dependence between the low lighting conditions and the number of traffic accidents in terms of three seasonal variations and a high probability of traffic accidents occurrence under the above-mentioned conditions, at the city entrances-exits, which represent also vulnerable areas within the study area. Knowing the linear dependence and the spatial relation between the low lighting and the number of traffic accidents, as well as the consequences induced by their occurrence enabled us to identify the high traffic accident risk areas in the city of Cluj-Napoca.

  19. Off-gas and air cleaning systems for accident conditions in nuclear power plants

    International Nuclear Information System (INIS)

    This report surveys the design principles and strategies for mitigating the consequences of abnormal events in nuclear power plants by the use of air cleaning systems. Equipment intended for use in design basis accident and severe accident conditions is reviewed, with reference to designs used in IAEA Member States. 93 refs, 48 figs, 23 tabs

  20. Robot dispatching Scenario for Accident Condition Monitoring of NPP

    International Nuclear Information System (INIS)

    In March of 2011, unanticipated big size of tsunami attacks Fukushima NPP, this accident results in explosion of containment building. Tokyo electric power of Japan couldn't dispatch a robot for monitoring of containment inside. USA Packbot robot used for desert war in Iraq was supplied to Fukushima NPP for monitoring of high radiation area. Packbot also couldn't reach deep inside of Fukushima NPP due to short length of power cable. Japanese robot 'Queens' also failed to complete a mission due to communication problem between robot and operator. I think major reason of these robot failures is absence of robot dispatching scenario. If there was a scenario and a rehearsal for monitoring during or after accident, these unanticipated obstacles could be overcome. Robot dispatching scenario studied for accident of nuclear power plant was described herein. Study on scenario of robot dispatching is performed. Flying robot is regarded as good choice for accident monitoring. Walking robot with arm equipped is good for emergency valve close. Short time work and shift work by several robots can be a solution for high radiation area. Thin and soft cable with rolling reel can be a good solution for long time work and good communication

  1. Thermal Analysis of a H1616-1 Shipping container in Hypothetical Accident conditions

    International Nuclear Information System (INIS)

    The thermal response of the H1616 transport container is simulated to demonstrate compliance with the Federal regulations for performance during hypothetical accident conditions (HAC). The goal is to show that tests conducted for the certification of the H1616 shipping container provide conservatively high estimates of temperatures at key regions within the container. A one-dimensional computational model is developed to simulate the thermal response of the shipping container in cylindrical coordinates. The model assumes the container is axisymmetric and allows for variable thermal properties. The model is calibrated using temperature data obtained FR-om two experimental thermal tests and is then used to evaluate the thermal response of the shipping container to several different scenarios that meet or exceed the Federal regulations. A pre-heating technique, which is used to simulate the thermal effects of a radioactive heat source within the container, is also evaluated

  2. Potential behavior of depleted uranium penetrators under shipping and bulk storage accident conditions

    International Nuclear Information System (INIS)

    An investigation of the potential hazard from airborne releases of depleted uranium (DU) from the Army's M829 munitions was conducted at the Pacific Northwest Laboratory. The study included: (1) assessing the characteristics of DU oxide from an April 1983 burn test, (2) postulating conditions of specific accident situations, and (3) reviewing laboratory and theoretical studies of oxidation and airborne transport of DU from accidents. Results of the experimental measurements of the DU oxides were combined with atmospheric transport models and lung and kidney exposure data to help establish reasonable exclusion boundaries to protect personnel and the public at an accident site. 121 references, 44 figures, 30 tables

  3. A review of iodine chemistry under severe accident conditions

    International Nuclear Information System (INIS)

    This report reviews the progress that has been made in establishing a basic understanding of the factors which will determine the behaviour of iodine during postulated accidents in water-cooled reactors. The topics considered are thermal reactions, radiolytic reactions, impurity effects, organic iodide formation, integral models and tests and volatility control. There have been substantial gains in a number of areas, most notably in the kinetics and thermodynamics databases for thermal and radiolytic reactions of inorganic iodine in solution. However, there remains a limited understanding of the mechanisms controlling the formation of organic iodides and a need for integral tests of iodine behaviour in complex, 'dirty' systems to provide data for the validation of chemical models which are undergoing development. 81 refs

  4. Key factors contributing to accident severity rate in construction industry in Iran: a regression modelling approach.

    Science.gov (United States)

    Soltanzadeh, Ahmad; Mohammadfam, Iraj; Moghimbeigi, Abbas; Ghiasvand, Reza

    2016-03-01

    Construction industry involves the highest risk of occupational accidents and bodily injuries, which range from mild to very severe. The aim of this cross-sectional study was to identify the factors associated with accident severity rate (ASR) in the largest Iranian construction companies based on data about 500 occupational accidents recorded from 2009 to 2013. We also gathered data on safety and health risk management and training systems. Data were analysed using Pearson's chi-squared coefficient and multiple regression analysis. Median ASR (and the interquartile range) was 107.50 (57.24- 381.25). Fourteen of the 24 studied factors stood out as most affecting construction accident severity (psafety and health risk management system to reduce ASR. PMID:27092639

  5. Monitoring of personal doses under normal and accident conditions

    International Nuclear Information System (INIS)

    Organization, legal structure and results of the control of personal doses in Lithuania are provided. Legal basis for monitoring of personal doses in Lithuania are the Basic Standards of Radiation Protection HN 73-1997 which are in force since January 1 1998. The General Order of Dosimetric Control in the Case of Radiation Accident has been approved by the Government on 12 May 1998. Dosimetric control consist of registration of equivalent dose rate and exposure rate, measurements of surface contamination, personal and group control of doses of persons taking part in remedial actions and members of public, radiometric control of foodstuff, drinking water and other samples. The Radiation Protection Centre of the Ministry of Health and Joint Research Center of the Ministry of Environment are responsible for organization, coordination and control of personal dosimetry according to their competence. Data on licensees and sources of ionizing radiation, results of monitoring of personal doses in medicine and Ignalina NPP during year 1995 - 1997 are presented as well

  6. Spherical steel containments of pressurized water reactors under accident conditions

    International Nuclear Information System (INIS)

    The investigations will deal with the mechanical behavior of 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 wall thickness is 38 mm. The material used is the ferritic steel 15MnNi63. The investigation program includes theoretical as well as experimental activities and concerns four different accidents which are beyond the scope of the common design and licensing practice: containment behavior under quasi-static pressure increase up to containment failure; containment behavior under high transient pressures; containment vibrations due to earthquake loadings (consideration of shell imperfections); containment buckling due to earthquake loadings. First results concerning the containment behavior under quasi-static pressure increase are presented. It turns out that the mechanical failure of the containment shell is controlled by plastic instability. A computer program to describe this problem has been developed and membrane tests to check the computational methods have been carried out. (orig.)

  7. Fuel Behaviour and Modelling under Severe Transient and Loss of Coolant Accident (LOCA) Conditions. Proceedings of a Technical Meeting

    International Nuclear Information System (INIS)

    the art of the performance of nuclear fuel for water cooled reactors under severe transients and LOCA conditions. The meeting was attended by 83 specialists representing fuel vendors, nuclear utilities, research and development institutions, and regulatory authorities from 19 Member States. The papers submitted to the meeting were organized into seven sessions covering analytical and experimental RIA and LOCA studies and international programmes, power ramp, and severe accident analysis. These proceedings contain all the papers that were presented and discussed during the meeting, and highlight key findings and recommendations based on the summaries of the session chairpersons. While the Fukushima Daiichi accident influenced the discussions, it was not directly considered because of the lack of fuel behaviour data available at the time of the technical meeting

  8. Preliminary Analysis of Radiation Shielding for HIC Transport Package Under the Hypothetical Accident Conditions

    International Nuclear Information System (INIS)

    A radiation shielding analysis under the hypothetical accident condition has been conducted using a computer program MCNP5 for a B-type HIC (High Integrated Container) Transport Package, which contains HIC with radioactive waste or spent resin, for transportation from nuclear power plat sites to disposal repository. Radiation source term is first carefully determined from the safety analysis reports related to HIC for appropriate calculation. And then MCNP5 is performed to obtain the minimum crevice between package lid and body, which meets the dose rate limit under the hypothetical accident conditions. Standards and codes of radiation shielding analysis related to the hypothetical accident condition are prescribed in Korea Nuclear Law, IAEA Safety Standards Series for Radioactive Material Transport and US 10CFR Part 71

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-05-15

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

  10. Behavior of HEPA filter systems under accident conditions

    International Nuclear Information System (INIS)

    With respect to the behavior of HEPA filters under high humidity conditions, emphasis was placed on the study of the differential pressure increase. Under fog conditions, the differential pressure of dust loaded filters increased within minutes, up to values sufficient to damage normal commercial filters units. The investigation into the failure mechanisms was completed with the development of an equation to calculate filter medium tensile stresses for two of the three most important modes of failure. Initial work was begun toward the development of a computer code to model transient fluiddynamic and thermodynamic conditions in complex air cleaning systems. Further investigation into the transmission of weak shock waves in air-cleaning system ductwork were carried out in branches of ducts with square cross-sections and with variable cross-sections. (orig./DG)

  11. Fuel Accident Condition Simulator (FACS) Furnace for Post-Irradiation Heating Tests of VHTR Fuel Compacts

    Energy Technology Data Exchange (ETDEWEB)

    Paul A Demkowicz; Paul Demkowicz; David V Laug

    2010-10-01

    Abstract –Fuel irradiation testing and post-irradiation examination are currently in progress as part of the Next Generation Nuclear Plant Fuels Development and Qualification Program. The PIE campaign will include extensive accident testing of irradiated very high temperature reactor fuel compacts to verify fission product retention characteristics at high temperatures. This work will be carried out at both the Idaho National Laboratory (INL) and the Oak Ridge National Laboratory, beginning with accident tests on irradiated fuel from the AGR-1 experiment in 2010. A new furnace system has been designed, built, and tested at INL to perform high temperature accident tests. The Fuel Accident Condition Simulator furnace system is designed to heat fuel specimens at temperatures up to 2000°C in helium while monitoring the release of volatile fission metals (e.g. Cs, Ag, Sr, Eu, and I) and fission gases (Kr, Xe). Fission gases released from the fuel to the sweep gas are monitored in real time using dual cryogenic traps fitted with high purity germanium detectors. Condensable fission products are collected on a plate attached to a water-cooled cold finger that can be exchanged periodically without interrupting the test. Analysis of fission products on the condensation plates involves dry gamma counting followed by chemical analysis of selected isotopes. This paper will describe design and operational details of the Fuel Accident Condition Simulator (FACS) furnace system, as well as preliminary system calibration results.

  12. Fuel Accident Condition Simulator (FACS) Furnace for Post-Irradiation Heating Tests of VHTR Fuel Compacts

    International Nuclear Information System (INIS)

    Fuel irradiation testing and post-irradiation examination are currently in progress as part of the Next Generation Nuclear Plant Fuels Development and Qualification Program. The PIE campaign will include extensive accident testing of irradiated very high temperature reactor fuel compacts to verify fission product retention characteristics at high temperatures. This work will be carried out at both the Idaho National Laboratory (INL) and the Oak Ridge National Laboratory, beginning with accident tests on irradiated fuel from the AGR-1 experiment in 2010. A new furnace system has been designed, built, and tested at INL to perform high temperature accident tests. The Fuel Accident Condition Simulator furnace system is designed to heat fuel specimens at temperatures up to 2000 C in helium while monitoring the release of volatile fission metals (e.g. Cs, Ag, Sr, Eu, and I) and fission gases (Kr, Xe). Fission gases released from the fuel to the sweep gas are monitored in real time using dual cryogenic traps fitted with high purity germanium detectors. Condensable fission products are collected on a plate attached to a water-cooled cold finger that can be exchanged periodically without interrupting the test. Analysis of fission products on the condensation plates involves dry gamma counting followed by chemical analysis of selected isotopes. This paper will describe design and operational details of the Fuel Accident Condition Simulator (FACS) furnace system, as well as preliminary system calibration results.

  13. Study on oxidation behavior of cladding for accident conditions in spent fuel pool

    International Nuclear Information System (INIS)

    In order to clarify the air oxidation behavior of the cladding at high temperatures for study on improvement of safety for accident conditions in spent fuel pool, the oxidation tests for both small specimens under constant temperature conditions and long specimens under loss of coolant simulated temperature conditions were carried out, and the knowledge for influence of both temperature gradient and preoxide film on oxidation behavior of the cladding were obtained in this study. (author)

  14. Experiences in methods to involve key players in planning protective actions in a case of nuclear accident

    International Nuclear Information System (INIS)

    Full text: Openness, transparency and key players participation are all important for balanced decision making in public issues. The emergency exercises involve commonly representatives from various sectors of the society to increase competence and build links for communication and coordination. A different approach has been a set of meetings where the key players aimed to plan comprehensive set of generic protective actions. The approach of this work was to develop methods and techniques to evaluate systematically and comprehensively protective action strategies. This was done in a way that all key players' concerns and issues related to decisions on protective actions could be aggregated openly and equally. We have developed and tested an approach called facilitated workshop based an theory of decision analysis. The work builds on case studies in which it was assumed that a hypothetical accident at a nuclear power plant had led to a release of considerable amounts of radionuclides and therefore various types of protective actions should be considered. Altogether six workshops were organized where all key players were represented, i.e., authorities, expert organizations, industry and producers. The participants were those who are responsible for preparing advice or making presentations of matters to those responsible for formal decision-making. Many preparatory meetings were held with various experts. It was seen essential that the setup followed strictly the decision-making process the participants are accustomed with. The realistic nature and the disciplined process of a facilitated workshop, and committed to decision-making yielded insight on what information should be collected or studied. Information should be in the proper form needed in decision-making. For example, the study revealed the need to further develop methods to assess the radiological and cost implications of different countermeasures realistically. In order to provide consequence assessments

  15. 10 CFR 71.74 - Accident conditions for air transport of plutonium.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Accident conditions for air transport of plutonium. 71.74 Section 71.74 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE... plutonium. (a) Test conditions—Sequence of tests. A package must be physically tested to the...

  16. Assessment of potential doses to workers during postulated accident conditions at the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hoover, M.D.; Farrell, R.F. [DOE, Carlsbad, NM (United States); Newton, G.J.

    1995-12-01

    The recent 1995 WIPP Safety Analysis Report (SAR) Update provided detailed analyses of potential radiation doses to members of the public at the site boundary during postulated accident scenarios at the U.S. Department of Energy`s Waste Isolation Pilot Plant (WIPP). The SAR Update addressed the complete spectrum of potential accidents associated with handling and emplacing transuranic waste at WIPP, including damage to waste drums from fires, punctures, drops, and other disruptions. The report focused on the adequacy of the multiple layers of safety practice ({open_quotes}defense-in-depth{close_quotes}) at WIPP, which are designed to (1) reduce the likelihood of accidents and (2) limit the consequences of those accidents. The safeguards which contribute to defense-in-depth at WIPP include a substantial array of inherent design features, engineered controls, and administrative procedures. The SAR Update confirmed that the defense-in-depth at WIPP is adequate to assure the protection of the public and environment. As a supplement to the 1995 SAR Update, we have conducted additional analyses to confirm that these controls will also provide adequate protection to workers at the WIPP. The approaches and results of the worker dose assessment are summarized here. In conformance with the guidance of DOE Standard 3009-94, we emphasize that use of these evaluation guidelines is not intended to imply that these numbers constitute acceptable limits for worker exposures under accident conditions. However, in conjunction with the extensive safety assessment in the 1995 SAR Update, these results indicate that the Carlsbad Area Office strategy for the assessment of hazards and accidents assures the protection of workers, members of the public, and the environment.

  17. Development of advanced claddings for suppressing the hydrogen emission in accident conditions. Development of advanced claddings for suppressing the hydrogen emission in the accident condition

    International Nuclear Information System (INIS)

    The development of accident-tolerant fuels can be a breakthrough to help solve the challenge facing nuclear fuels. One of the goals to be reached with accident-tolerant fuels is to reduce the hydrogen emission in the accident condition by improving the high-temperature oxidation resistance of claddings. KAERI launched a new project to develop the accident-tolerant fuel claddings with the primary objective to suppress the hydrogen emission even in severe accident conditions. Two concepts are now being considered as hydrogen-suppressed cladding. In concept 1, the surface modification technique was used to improve the oxidation resistance of Zr claddings. Like in concept 2, the metal-ceramic hybrid cladding which has a ceramic composite layer between the Zr inner layer and the outer surface coating is being developed. The high-temperature steam oxidation behaviour was investigated for several candidate materials for the surface modification of Zr claddings. From the oxidation tests carried out in 1 200 deg. C steam, it was found that the high-temperature steam oxidation resistance of Cr and Si was much higher than that of zircaloy-4. Al3Ti-based alloys also showed extremely low-oxidation rate compared to zircaloy-4. One important part in the surface modification is to develop the surface coating technology where the optimum process needs to be established depending on the surface layer materials. Several candidate materials were coated on the Zr alloy specimens by a laser beam scanning (LBS), a plasma spray (PS) and a PS followed by LBS and subject to the high-temperature steam oxidation test. It was found that Cr and Si coating layers were effective in protecting Zr-alloys from the oxidation. The corrosion behaviour of the candidate materials in normal reactor operation condition such as 360 deg. C water will be investigated after the screening test in the high-temperature steam. The metal-ceramic hybrid cladding consisted of three major parts; a Zr liner, a ceramic

  18. Potential for containment leak paths through electrical penetration assemblies under severe accident conditions. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Sebrell, W.

    1983-07-01

    The leakage behavior of containments beyond design conditions and knowledge of failure modes is required for evaluation of mitigation strategies for severe accidents, risk studies, emergency preparedness planning, and siting. These studies are directed towards assessing the risk and consequences of severe accidents. An accident sequence analysis conducted on a Boiling Water Reactor (BWR), Mark I (MK I), indicated very high temperatures in the dry-well region, which is the location of the majority of electrical penetration assemblies. Because of the high temperatures, it was postulated in the ORNL study that the sealants would fail and all the electrical penetration assemblies would leak before structural failure would occur. Since other containments had similar electrical penetration assemblies, it was concluded that all containments would experience the same type of failure. The results of this study, however, show that this conclusion does not hold for PWRs because in the worst accident sequence, the long time containment gases stabilize to 350/sup 0/F. BWRs, on the other hand, do experience high dry-well temperatures and have a higher potential for leakage.

  19. Most likely vessel lower head failure location during severe accident conditions

    International Nuclear Information System (INIS)

    The Nuclear Regulatory Commission is sponsoring a lower vessel head research program to investigate plausible modes of reactor vessel failure to determine: (a) which modes have the greatest likelihood of occurrence during a severe accident and (b) the range of core debris and accident conditions that lead to these failures. All major types of US light water reactor vessels are being considered, and both high- and low-pressure conditions are being addressed for each reactor type. The research program includes analytical and finite element calculations. In addition, high temperature creep and tensile data for predicting vessel structural response were obtained. Calculational results used to predict which failure location is more likely in a particular reactor design during a severe accident are described within this paper. Detailed analyses are being performed to investigate the relative likelihood of a BWR penetration and vessel to fail during a wide range of severe accident conditions. The analyses include applying a numerical model to obtain the penetration and vessel thermal response and applying an analytical model to investigate the relative likelihood of tube rupture and global vessel failure. Sensitivity studies considered the impact of assumptions related to debris composition, debris porosity, corium decay heat, vessel coolant mass, heat removal from the vessel, melt relocation time, and melt relocation distance on vessel and penetration response. In addition, analytically developed failure maps, which were developed in terms of dimensionless groups, are applied to extrapolate numerically-obtained results to geometries and materials occurring in PWR penetration/vessel configurations and a wide range of debris conditions

  20. Study on probability of failure for RPV nozzle region under severe accident condition

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Il Soon; Oh, Young Jin; Sim, Sang Hoon [Seoul National University, Seoul (Korea)

    2002-04-01

    Most of previous studies for creep rupture of RPV lower head under severe accident condition, have been focused on global failure of RPV lower head. In contrast, the local failure of the RPV nozzle region has not been studied in detail. This study focused the nozzle failure analysis into creep rupture evaluation of RPV lower head under severe accident condition, and this will help improve the safety assessment of nuclear power plants under severe accident conditions. The existence and features of nozzle failure in LAVA-ICI tested vessel of Korea Atomic Energy Research Institute and LHF-4 tested vessel of SNL, are examined. To understand the basic mechanical properties of nozzle material and weld metal, the tensile tests in various temperature levels and the creep rupture tests in various temperature and stress levels, are accomplished. The stress and deformation of LAVA-ICI experiments are analysed using measured basic mechanical properties. The failure time of Advanced Power Reactor 1400 (APR1400) in nozzle region was calculated using modified TMI-2 VIP model. Nozzle region failure characteristics was studied for SNL-LHF-4 experimental case using Finite Element Method (FEM). Using characteristics of nozzle failure, a new failure prediction experimental method was proposed for RPV nozzle failure. 19 refs., 43 figs. (Author)

  1. Shipping container response to severe highway and railway accident conditions: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, L.E.; Chou, C.K.; Gerhard, M.A.; Kimura, C.Y.; Martin, R.W.; Mensing, R.W.; Mount, M.E.; Witte, M.C.

    1987-02-01

    Volume 2 contains the following appendices: Severe accident data; truck accident data; railroad accident data; highway survey data and bridge column properties; structural analysis; thermal analysis; probability estimation techniques; and benchmarking for computer codes used in impact analysis. (LN)

  2. Shipping container response to severe highway and railway accident conditions: Appendices

    International Nuclear Information System (INIS)

    Volume 2 contains the following appendices: Severe accident data; truck accident data; railroad accident data; highway survey data and bridge column properties; structural analysis; thermal analysis; probability estimation techniques; and benchmarking for computer codes used in impact analysis. (LN)

  3. Identification of the security threshold by logistic regression applied to fuel under accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Daniel de Souza; Baptista Filho, Benedito; Oliveira, Fabio Branco de, E-mail: dsgomes@ipen.br, E-mail: bdbfilho@ipen.br, E-mail: fabio@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Giovedi, Claudia, E-mail: claudia.giovedi@labrisco.usp.br [Universidade de Sao Paulo (POLI/USP), Sao Paulo, SP (Brazil). Lab. de Analise, Avaliacao e Gerenciamento de Risco

    2015-07-01

    A reactivity-initiated Accident (RIA) is a disastrous failure, which occurs because of an unexpected rise in the fission rate and reactor power. This sudden increase in the reactor power may activate processes that might lead to the failure of fuel cladding. In severe accidents, a disruption of fuel and core melting can occur. The purpose of the present research is to study the patterns of such accidents using exploratory data analysis techniques. A study based on applied statistics was used for simulations. Then, we chose peak enthalpy, pulse width, burnup, fission gas release, and the oxidation of zirconium as input parameters and set the safety boundary conditions. This new approach includes the logistic regression. With this, the present research aims also to develop the ability to identify the conditions and the probability of failures. Zirconium-based alloys fabricating the cladding of the fuel rod elements with niobium 1% were analyzed for high burnup limits at 65 MWd/kgU. The data based on six decades of investigations from experimental programs. In test, perform in American reactors such as the transient reactor test (TREAT), and power Burst Facility (PBF). In experiments realized in Japanese program at nuclear in the safety research reactor (NSRR), and in Kazakhstan as impulse graphite reactor (IGR). The database obtained from the tests and served as a support for our study. (author)

  4. Evaluating the Effectiveness of Alternate Entry Condition into the Severe Accident Management Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hyung Seok; Lee, Su Won [FNC Technology Co. Ltd., Yongin (Korea, Republic of); Min, Shin Jung [Korea Hydro and Nuclear Power Co. Ltd. Central Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this study, the effectiveness of the CA as an alternate means is evaluated quantitatively by utilizing the Modular Accident Analysis Program (MAAP) 5 computer code including the MAAP5-DOSE module, which can analyze the radiation level inside the containment. The effectiveness of the CA has been investigated by utilizing the MAAP5 code including the MAAP5- DOSE. The onset of core damage is considered to be a core (fuel rod cladding) condition at the time when the core exit temperature reaches the value prescribed for transition to Severe Accident Management Guidance (SAMG), which is 1200 .deg. F. However, during a shutdown state, the core exit thermocouples measurements are unavailable after lifting reactor vessel head. Thus, an alternate means to detect the onset of core damage is necessary to cover all plant operating states. In order for that, a Computational Aid (CA), 'Radiation Level as a Functional of Time after Shutdown,' has been developed. The upper containment radiation instrumentation is a gross gamma monitor, and has a reliable instrumentation range during severe accidents. It can be used for detecting onset of core damage. Thus, the radiation level can be used as alternative means of the entry condition into the SAMG. It has been shown that the SAMG entry timings determined by using the core exit thermocouple measurements and by the radiation monitoring with the CA would not be differentiated. The time difference estimates entering SAMG would be less 15 min which would not influence the operator action significantly.

  5. Fission products behaviour in UO2 submitted to nuclear severe accident conditions

    Science.gov (United States)

    Geiger, E.; Bès, R.; Martin, P.; Pontillon, Y.; Solari, P. L.; Salome, M.

    2016-05-01

    The objective of this work was to study the molybdenum chemistry in UO2 based materials, known as SIMFUELS. These materials could be used as an alternative to irradiated nuclear fuels in the study of fission products behaviour during a nuclear severe accident. UO2 samples doped with 12 stable isotopes of fission products were submitted to annealing tests in conditions representative to intermediate steps of severe accidents. Samples were characterized by SEM-EDS and XAS. It was found that Mo chemistry seems to be more complex than what is normally estimated by thermodynamic calculations: XAS spectra indicate the presence of Mo species such as metallic Mo, MoO2, MoO3 and Cs2MoO4.

  6. Analysis 320 coal mine accidents using structural equation modeling with unsafe conditions of the rules and regulations as exogenous variables.

    Science.gov (United States)

    Zhang, Yingyu; Shao, Wei; Zhang, Mengjia; Li, Hejun; Yin, Shijiu; Xu, Yingjun

    2016-07-01

    Mining has been historically considered as a naturally high-risk industry worldwide. Deaths caused by coal mine accidents are more than the sum of all other accidents in China. Statistics of 320 coal mine accidents in Shandong province show that all accidents contain indicators of "unsafe conditions of the rules and regulations" with a frequency of 1590, accounting for 74.3% of the total frequency of 2140. "Unsafe behaviors of the operator" is another important contributory factor, which mainly includes "operator error" and "venturing into dangerous places." A systems analysis approach was applied by using structural equation modeling (SEM) to examine the interactions between the contributory factors of coal mine accidents. The analysis of results leads to three conclusions. (i) "Unsafe conditions of the rules and regulations," affect the "unsafe behaviors of the operator," "unsafe conditions of the equipment," and "unsafe conditions of the environment." (ii) The three influencing factors of coal mine accidents (with the frequency of effect relation in descending order) are "lack of safety education and training," "rules and regulations of safety production responsibility," and "rules and regulations of supervision and inspection." (iii) The three influenced factors (with the frequency in descending order) of coal mine accidents are "venturing into dangerous places," "poor workplace environment," and "operator error." PMID:27085591

  7. Analysis 320 coal mine accidents using structural equation modeling with unsafe conditions of the rules and regulations as exogenous variables.

    Science.gov (United States)

    Zhang, Yingyu; Shao, Wei; Zhang, Mengjia; Li, Hejun; Yin, Shijiu; Xu, Yingjun

    2016-07-01

    Mining has been historically considered as a naturally high-risk industry worldwide. Deaths caused by coal mine accidents are more than the sum of all other accidents in China. Statistics of 320 coal mine accidents in Shandong province show that all accidents contain indicators of "unsafe conditions of the rules and regulations" with a frequency of 1590, accounting for 74.3% of the total frequency of 2140. "Unsafe behaviors of the operator" is another important contributory factor, which mainly includes "operator error" and "venturing into dangerous places." A systems analysis approach was applied by using structural equation modeling (SEM) to examine the interactions between the contributory factors of coal mine accidents. The analysis of results leads to three conclusions. (i) "Unsafe conditions of the rules and regulations," affect the "unsafe behaviors of the operator," "unsafe conditions of the equipment," and "unsafe conditions of the environment." (ii) The three influencing factors of coal mine accidents (with the frequency of effect relation in descending order) are "lack of safety education and training," "rules and regulations of safety production responsibility," and "rules and regulations of supervision and inspection." (iii) The three influenced factors (with the frequency in descending order) of coal mine accidents are "venturing into dangerous places," "poor workplace environment," and "operator error."

  8. Status Report on Spent Fuel Pools under Loss-of-Cooling and Loss-of-Coolant Accident Conditions - Final Report

    International Nuclear Information System (INIS)

    Following the 2011 accident at the Fukushima Daiichi Nuclear Power Station, the Nuclear Energy Agency Committee on the Safety of Nuclear Installations decided to launch several high-priority activities to address certain technical issues. Among other things, it was decided to prepare a status report on spent fuel pools (SFPs) under loss of cooling accident conditions. This activity was proposed jointly by the CSNI Working Group on Analysis and Management of Accidents (WGAMA) and the Working Group on Fuel Safety (WGFS). The main objectives, as defined by these working groups, were to: - Produce a brief summary of the status of SFP accident and mitigation strategies, to better contribute to the post-Fukushima accident decision making process; - Provide a brief assessment of current experimental and analytical knowledge about loss of cooling accidents in SFPs and their associated mitigation strategies; - Briefly describe the strengths and weaknesses of analytical methods used in codes to predict SFP accident evolution and assess the efficiency of different cooling mechanisms for mitigation of such accidents; - Identify and list additional research activities required to address gaps in the understanding of relevant phenomenological processes, to identify where analytical tool deficiencies exist, and to reduce the uncertainties in this understanding. The proposed activity was agreed and approved by CSNI in December 2012, and the first of four meetings of the appointed writing group was held in March 2013. The writing group consisted of members of the WGAMA and the WGFS, representing the European Commission and the following countries: Belgium, Canada, Czech Republic, France, Germany, Hungary, Italy, Japan, Korea, Spain, Sweden, Switzerland and the USA. This report mostly covers the information provided by these countries. The report is organised into 8 Chapters and 4 Appendices: Chapter 1: Introduction; Chapter 2: Spent fuel pools; Chapter 3: Possible accident

  9. Design feasibility study on corium stabilization in bottom end-fitting for AHWR under accident condition

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor (AHWR) is being designed in a robust way to cater both Design and Beyond Design Basis Accidents to meet all the safety functions. All the functions are met by passive means with special emphasis on 'residual heat removal' which is catered by passive natural circulation mode. In context to Design Basis Accidents, several features are designed to handle worst kind of scenario like Station Black Out. For Design Extension Conditions (DEC), the means of passive natural circulation is adopted as a design means to meet the DEC-A conditions like cooling of moderator by natural circulation means with GDWP inventory. Under the DEC-B condition where large scale of fuel melting is envisaged, a core catcher is designed with active/passive cooling modes to take care of the residual heat of the core. All the mentioned features utilizes the natural mode of heat transfer to meet one of the safety function i.e. 'residual heat removal'. The analysis shows that the tube sheet as well as lattice tube temperatures remain low and are able to take out the heat from corium through sub-cooled nucleate boiling. The ES cooling is sufficient to maintain the cooling water in subcooled condition. The integrity of tube sheet and lattice tube is maintained

  10. Role of Winter Weather Conditions and Slipperiness on Tourists’ Accidents in Finland

    Directory of Open Access Journals (Sweden)

    Élise Lépy

    2016-08-01

    Full Text Available (1 Background: In Finland, slippery snowy or icy ground surface conditions can be quite hazardous to human health during wintertime. We focused on the impacts of the variability in weather conditions on tourists’ health via documented accidents during the winter season in the Sotkamo area. We attempted to estimate the slipping hazard in a specific context of space and time focusing on the weather and other possible parameters, responsible for fluctuations in the numbers of injuries/accidents; (2 Methods: We used statistical distributions with graphical illustrations to examine the distribution of visits to Kainuu Hospital by non-local patients and their characteristics/causes; graphs to illustrate the distribution of the different characteristics of weather conditions; questionnaires and interviews conducted among health care and safety personnel in Sotkamo and Kuusamo; (3 Results: There was a clear seasonal distribution in the numbers and types of extremity injuries of non-local patients. While the risk of slipping is emphasized, other factors leading to injuries are evaluated; and (4 Conclusions: The study highlighted the clear role of wintery weather conditions as a cause of extremity injuries even though other aspects must also be considered. Future scenarios, challenges and adaptive strategies are also discussed from the viewpoint of climate change.

  11. Role of Winter Weather Conditions and Slipperiness on Tourists’ Accidents in Finland

    Science.gov (United States)

    Lépy, Élise; Rantala, Sinikka; Huusko, Antti; Nieminen, Pentti; Hippi, Marjo; Rautio, Arja

    2016-01-01

    (1) Background: In Finland, slippery snowy or icy ground surface conditions can be quite hazardous to human health during wintertime. We focused on the impacts of the variability in weather conditions on tourists’ health via documented accidents during the winter season in the Sotkamo area. We attempted to estimate the slipping hazard in a specific context of space and time focusing on the weather and other possible parameters, responsible for fluctuations in the numbers of injuries/accidents; (2) Methods: We used statistical distributions with graphical illustrations to examine the distribution of visits to Kainuu Hospital by non-local patients and their characteristics/causes; graphs to illustrate the distribution of the different characteristics of weather conditions; questionnaires and interviews conducted among health care and safety personnel in Sotkamo and Kuusamo; (3) Results: There was a clear seasonal distribution in the numbers and types of extremity injuries of non-local patients. While the risk of slipping is emphasized, other factors leading to injuries are evaluated; and (4) Conclusions: The study highlighted the clear role of wintery weather conditions as a cause of extremity injuries even though other aspects must also be considered. Future scenarios, challenges and adaptive strategies are also discussed from the viewpoint of climate change. PMID:27537899

  12. Role of Winter Weather Conditions and Slipperiness on Tourists' Accidents in Finland.

    Science.gov (United States)

    Lépy, Élise; Rantala, Sinikka; Huusko, Antti; Nieminen, Pentti; Hippi, Marjo; Rautio, Arja

    2016-01-01

    (1) BACKGROUND: In Finland, slippery snowy or icy ground surface conditions can be quite hazardous to human health during wintertime. We focused on the impacts of the variability in weather conditions on tourists' health via documented accidents during the winter season in the Sotkamo area. We attempted to estimate the slipping hazard in a specific context of space and time focusing on the weather and other possible parameters, responsible for fluctuations in the numbers of injuries/accidents; (2) METHODS: We used statistical distributions with graphical illustrations to examine the distribution of visits to Kainuu Hospital by non-local patients and their characteristics/causes; graphs to illustrate the distribution of the different characteristics of weather conditions; questionnaires and interviews conducted among health care and safety personnel in Sotkamo and Kuusamo; (3) RESULTS: There was a clear seasonal distribution in the numbers and types of extremity injuries of non-local patients. While the risk of slipping is emphasized, other factors leading to injuries are evaluated; and (4) CONCLUSIONS: The study highlighted the clear role of wintery weather conditions as a cause of extremity injuries even though other aspects must also be considered. Future scenarios, challenges and adaptive strategies are also discussed from the viewpoint of climate change. PMID:27537899

  13. Characterization and chemistry of fission products released from LWR fuel under accident conditions

    International Nuclear Information System (INIS)

    Segments from commercial LWR fuel rods have been tested at temperatures between 1400 and 20000C in a flowing steam-helium atmosphere to simulate severe accident conditions. The primary goals of the tests were to determine the rate of fission product release and to characterize the chemical behavior. This paper is concerned primarily with the identification and chemical behavior of the released fission products with emphasis on antimony, cesium, iodine, and silver. The iodine appeared to behave primarily as cesium iodide and the antimony and silver as elements, while cesium behavior was much more complex. 17 refs., 7 figs., 1 tab

  14. Experimental results from containment piping bellows subjected to severe accident conditions: Results from bellows tested in corroded conditions. Volume 2

    International Nuclear Information System (INIS)

    Bellows are an integral part of the containment pressure boundary in nuclear power plants. They are used at piping penetrations to allow relative movement between piping and the containment wall, while minimizing the load imposed on the piping and wall. Piping bellows are primarily used in steel containments; however, they have received limited use in some concrete (reinforced and prestressed) containments. In a severe accident they may be subjected to pressure and temperature conditions that exceed the design values, along with a combination of axial and lateral deflections. A test program to determine the leak-tight capacity of containment penetration bellows is being conducted at Sandia National Laboratories under the sponsorship of the US Nuclear Regulatory Commission. Several different bellows geometries, representative of actual containment bellows, have been subjected to extreme deflections along with pressure and temperature loads. The bellows geometries and loading conditions are described along with the testing apparatus and procedures. A total of nineteen bellows have been tested. Thirteen bellows were tested in ''like-new'' condition (results reported in Volume 1), and six were tested in a corroded condition. The tests showed that bellows in ''like-new'' condition are capable of withstanding relatively large deformations, up to, or near, the point of full compression or elongation, before developing leakage, while those in a corroded condition did not perform as well, depending on the amount of corrosion. The corroded bellows test program and results are presented in this report

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

    International Nuclear Information System (INIS)

    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)

  16. Comparison and verification of two computer programs used to analyze ventilation systems under accident conditions

    International Nuclear Information System (INIS)

    Two computer codes, TVENT and EVENT, which were developed at the Los Alamos National Laboratory (LANL) for the analysis of ventilation systems, have been modified to model air-cleaning systems that include active components with time-dependent flow-resistance characteristics. With both modified programs, fluid-dynamic transients were calculated for a test facility used to simulate accident conditions in air-cleaning systems. Experiments were performed in the test facility whereby flow and pressure transients were generated with the help of two quick-actuating air-stream control valves. The numerical calculations are compared with the test results. Although EVENT makes use of a more complex theoretical flow model than TVENT, the numerical simulations of both codes were found to be very similar for the flow conditions studied and to closely follow the experimental results

  17. Iodine behaviour under LWR accident conditions: Lessons learnt from analyses of the first two Phebus FP tests

    International Nuclear Information System (INIS)

    The International Phebus Fission Product programme, initiated in 1988 and performed by the French 'Institut de Radioprotection et de Surete Nucleaire' (IRSN), investigates through a series of in-pile integral experiments, key phenomena involved in light water reactor (LWR) severe accidents. The tests cover fuel rod degradation and the behaviour of fission products released via the primary coolant circuit into the containment building. The results of the first two tests, called FPT0 and Ftp, carried out under low pressure, in a steam rich atmosphere and using fresh fuel for Ftp and fuel burned in a reactor at 23 GWdt-1 for Ftp, were immensely challenging, especially with regard to the iodine radiochemistry. Some of the most important observed phenomena with regard to the chemistry of iodine were indeed neither predicted nor pre-calculated, which clearly shows the interest and the need for carrying out integral experiments to study the complex phenomena governing fission product behaviour in a PWR in accident conditions. The three most unexpected results in the iodine behaviour related to early detection during fuel degradation of a weak but significant fraction of volatile iodine in the containment, the key role played by silver rapidly binding iodine to form insoluble AgI in the containment sump and the importance of painted surfaces in the containment atmosphere for the formation of a large quantity of volatile organic iodides. To support the Phebus test interpretation small-scale analytical experiments and computer code analyses were carried out. The former, helping towards a better understanding of overall iodine behaviour, were used to develop or improve models while the latter mainly aimed at identifying relevant key phenomena and at modelling weaknesses. Specific efforts were devoted to exploring the potential origins of the early-detected volatile iodine in the containment building. If a clear explanation has not yet been found, the non-equilibrium chemical

  18. RADIATION CONDITIONS IN KALUGA REGION 30 YEARS AFTER CHERNOBYL NPP ACCIDENT

    Directory of Open Access Journals (Sweden)

    A. G. Ashitko

    2016-01-01

    Full Text Available The article describes radiation conditions in the Kaluga region 30 years after the Chernobyl NPP accident. The Chernobyl NPP accident caused radioactive contamination of nine Kaluga region territories: Duminichsky, Zhizdrinsky, Kuibyshevsky, Kirovsky, Kozelsky, Ludinovsky, Meshchovsky, Ulyanovsky and Hvastovichsky districts. Radioactive fallout was the strongest in three southern districts: Zhizdrinsky, Ulyanovsky and Hvastovichsky, over there cesium-137 contamination density is from 1 to 15Ci/km. According to the Russian Federation Government Order in 2015 there are 300 settlements (S in the radioactive contamination zone, including 14 settlements with caesium-137 soil contamination density from 5 to 15 Ci/ km2 and 286 settlements with the contamination density ranging from 1 to 5 Ci/km2. In the first years after the Chernobyl NPP accident in Kaluga region territories, contaminated with caesium-137, there were introduced restrictive land usage, were carried out agrochemical activities (ploughing, mineral fertilizer dressing, there was toughened laboratory radiation control over the main doze-forming foodstuff. All these measures facilitated considerable decrease of caesium-137 content in local agricultural produce. Proceeding from the achieved result, in 2002 there took place the transition to more tough requirements SanPiN 2.3.2.1078-01. Analysis of investigated samples from Zhizdrinsky, Ulyanovsky and Hvastovichsky districts demonstrated that since 2005 meat samples didn’t exceed the standard values, same for milk samples since 2007. Till the present time, the use of wild-growing mushrooms, berries and wild animals meat involves radiation issues. It was demonstrated that average specific activity of caesium-137 in milk samples keeps decreasing year after year. Long after the Chernobyl NPP accident, the main products forming internal irradiation doses in population are the wild-growing mushrooms and berries. Population average annual

  19. Containment performance of prototypical reactor containments subjected to severe accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Klamerus, E.W.; Bohn, M.P. [Sandia National Labs., Albuquerque, NM (United States); Wesley, D.A. [EQE International, Irvine, CA (United States); Krishnaswamy, C.N. [Sargent & Lundy, Chicago, IL (United States)

    1996-12-01

    In SECY-90-016, the NTRC proposed a safety goal of a conditional containment failure probability (CCFP) of 0.1 and the alternative acceptance criteria allowed for steel containments, which specifies that the stresses should not exceed ASNE Level C allowables for severe accident pressures and temperatures. In this work, the need for an equivalent criterion for concrete containments was studied. Six surrogate containments were designed and analyzed in order to compare the margins between design pressure, pressure resulting in exceedance of Level C (or yield) stress limits, and ultimate pressure. For comparability, each containment has an identical internal volume and design pressure. Results from the analysis showed margins to yield are comparable and display a similar margin for both steel and concrete containments. In addition, the margin to failure, although slightly higher in the steel containments, were also comparable. Finally, a CCFP for code design was determined based on general membrane behavior and imposing an upper bound severe accident curve developed in the DCH studies. The resulting CCFP`s were less then 0.02 (or 2%) for all the surrogate containments studied, showing that these containment designs all achieved the NRC safety goal.

  20. Insights on fission products behaviour in nuclear severe accident conditions by X-ray absorption spectroscopy

    Science.gov (United States)

    Geiger, E.; Bès, R.; Martin, Ph; Pontillon, Y.; Ducros, G.; Solari, P. L.

    2016-04-01

    Many research programs have been carried out aiming to understand the fission products behaviour during a Nuclear Severe Accident. Most of these programs used highly radioactive irradiated nuclear fuel, which requires complex instrumentation. Moreover, the radioactive character of samples hinders an accurate chemical characterisation. In order to overcome these difficulties, SIMFUEL stand out as an alternative to perform complementary tests. A sample made of UO2 doped with 11 fission products was submitted to an annealing test up to 1973 K in reducing atmosphere. The sample was characterized before and after the annealing test using SEM-EDS and XAS at the MARS beam-line, SOLEIL Synchrotron. It was found that the overall behaviour of several fission products (such as Mo, Ba, Pd and Ru) was similar to that observed experimentally in irradiated fuels and consistent with thermodynamic estimations. The experimental approach presented in this work has allowed obtaining information on chemical phases evolution under nuclear severe accident conditions, that are yet difficult to obtain using irradiated nuclear fuel samples.

  1. Neutronics and Fuel Performance Evaluation of Accident Tolerant Fuel under Normal Operation Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Xu Wu; Piyush Sabharwall; Jason Hales

    2014-07-01

    This report details the analysis of neutronics and fuel performance analysis for enhanced accident tolerance fuel, with Monte Carlo reactor physics code Serpent and INL’s fuel performance code BISON, respectively. The purpose is to evaluate two of the most promising candidate materials, FeCrAl and Silicon Carbide (SiC), as the fuel cladding under normal operating conditions. Substantial neutron penalty is identified when FeCrAl is used as monolithic cladding for current oxide fuel. From the reactor physics standpoint, application of the FeCrAl alloy as coating layer on surface of zircaloy cladding is possible without increasing fuel enrichment. Meanwhile, SiC brings extra reactivity and the neutron penalty is of no concern. Application of either FeCrAl or SiC could be favorable from the fuel performance standpoint. Detailed comparison between monolithic cladding and hybrid cladding (cladding + coating) is discussed. Hybrid cladding is more practical based on the economics evaluation during the transition from current UO2/zircaloy to Accident Tolerant Fuel (ATF) system. However, a few issues remain to be resolved, such as the creep behavior of FeCrAl, coating spallation, inter diffusion with zirconium, etc. For SiC, its high thermal conductivity, excellent creep resistance, low thermal neutron absorption cross section, irradiation stability (minimal swelling) make it an excellent candidate materials for future nuclear fuel/cladding system.

  2. Nuclear waste shipping container response to severe accident conditions, A brief critique of the modal study

    Energy Technology Data Exchange (ETDEWEB)

    Audin, L.

    1990-12-01

    The Modal Study (NUREG/CR-4829) attempts to upgrade the analysis of spent nuclear fuel transportation accidents, and to verify the validity of the present regulatory scheme of cask performance standards as a means to minimize risk. While an improvement over many prior efforts in this area (such as NUREG-0170), it unfortunately fails to create a realistic simulation either of a shipping cask, the severe conditions to which it could be subjected, or the potential damage to the spent fuel cargo during an accident. There are too many deficiencies in its analysis to allow acceptance of its results for the presumed cask design, and many pending changes in new containers, cargoes and shipping patterns will limit applicability of the Modal Study to future shipments. In essence, the Modal Study is a good start, but is too simplistic, incomplete, outdated and open to serious question to be used as the basis for any present-day environmental or risk assessment of spent fuel transportation. It needs to be redone, with peer review during its production and experimental verification of its assumptions, before it has any relevance to the shipments planned to Yucca Mountain. Finally, it must be expanded into a full risk assessment by inputing its radiological release fractions and probabilities into a valid dispersal simulation to properly determine the impact of its results. 51 refs.

  3. Nuclear waste shipping container response to severe accident conditions, A brief critique of the modal study

    International Nuclear Information System (INIS)

    The Modal Study (NUREG/CR-4829) attempts to upgrade the analysis of spent nuclear fuel transportation accidents, and to verify the validity of the present regulatory scheme of cask performance standards as a means to minimize risk. While an improvement over many prior efforts in this area (such as NUREG-0170), it unfortunately fails to create a realistic simulation either of a shipping cask, the severe conditions to which it could be subjected, or the potential damage to the spent fuel cargo during an accident. There are too many deficiencies in its analysis to allow acceptance of its results for the presumed cask design, and many pending changes in new containers, cargoes and shipping patterns will limit applicability of the Modal Study to future shipments. In essence, the Modal Study is a good start, but is too simplistic, incomplete, outdated and open to serious question to be used as the basis for any present-day environmental or risk assessment of spent fuel transportation. It needs to be redone, with peer review during its production and experimental verification of its assumptions, before it has any relevance to the shipments planned to Yucca Mountain. Finally, it must be expanded into a full risk assessment by inputing its radiological release fractions and probabilities into a valid dispersal simulation to properly determine the impact of its results. 51 refs

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  5. Development of Instrument Transmitter Protecting Device against High-Temperature Condition during Severe Accidents

    OpenAIRE

    Min Yoo; Sung Min Shin; Hyun Gook Kang

    2014-01-01

    Reliable information through instrumentation systems is essential in mitigating severe accidents such as the one that occurred at the Fukushima Daiichi nuclear power plant. There are five elements which might pose a potential threat to the reliability of parameter detection at nuclear power plants during a severe accident: high temperature, high pressure, high humidity, high radiation, and missiles generated during the evolution of a severe accident. Of these, high temperature apparently pose...

  6. Need for Replications of Key Studies in Covert Conditioning.

    Science.gov (United States)

    Livingston, Roger H.; Elson, Steven E.

    There is a considerable body of research that involves covert antecedents and consequences of behavior, and how these factors tend to influence overt behavior. As is frequently the case in new areas of endeavor, overenthusiastic claims have been made for covert conditioning procedures, often based on poorly controlled experiments or clinical…

  7. Characterization of PWR vessel steel tearing under severe accident condition temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Matheron, Philippe, E-mail: philippe.matheron@cea.fr [CEA, DEN, DM2S, SEMT, F-91191 Gif-sur-Yvette (France); Chapuliot, Stephane, E-mail: stephane.chapuliot@cea.fr [CEA, DEN, DM2S, SEMT, F-91191 Gif-sur-Yvette (France); Nicolas, Laetitia, E-mail: laetitia.nicolas@cea.fr [CEA, DEN, DM2S, SEMT, F-91191 Gif-sur-Yvette (France); Laboratoire de Mecanique des Structures Industrielles Durables, UMR CNRS-EDF 2832, 1 avenue du General de Gaulle, F-92141 Clamart (France); Koundy, Vincent, E-mail: vincent.koundy@irsn.fr [IRSN-DSR, Service d' evaluation des Accidents Graves et des Rejets radioactifs B.P. 17, 92262 Fontenay-aux-Roses Cedex (France); Caroli, Cataldo, E-mail: cataldo.caroli@irsn.fr [IRSN-DSR, Service d' evaluation des Accidents Graves et des Rejets radioactifs B.P. 17, 92262 Fontenay-aux-Roses Cedex (France)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer We characterized French PWR vessel steel tearing resistance at high temperatures. Black-Right-Pointing-Pointer Tearing tests on Compact Tension (CT) specimens were carried out. Black-Right-Pointing-Pointer The variability of tearing properties with PWR vessels specifications was studied. Black-Right-Pointing-Pointer We propose a tearing criterion (energy parameter Gfr) at high temperatures. - Abstract: In the event of a severe core meltdown accident in a pressurised water reactor (PWR), core material can relocate into the lower head of the vessel resulting in significant thermal and pressure loads being imposed on the vessel. In the event of reactor pressure vessel (RPV) failure there is the possibility of core material being released towards the containment. On the basis of the loading conditions and the temperature distribution, the determination of the mode, timing, and size of lower head failure is of prime importance in the assessment of core melt accidents. This is because they define the initial conditions for ex-vessel events such as core/basemat interactions, fuel/coolant interactions, and direct containment heating. When lower head failure occurs (i) the understanding of the mechanism of lower head creep deformation; (ii) breach stability and its kinetic of propagation leading to the failure; (iii) and developing predictive modelling capabilities to better assess the consequences of ex-vessel processes, are of equal importance. The objective of this paper is to present an original characterization programme of vessel steel tearing properties by carrying out high temperature tearing tests on Compact Tension (CT) specimens. The influence of metallurgical composition on the kinetics of tearing is investigated as previous work on different RPV steels has shown a possible loss of ductility at high temperatures depending on the initial chemical composition of the vessel material. Small changes in the composition can lead

  8. Advances in fracture mechanics analyses of primary system performance under operating and accident conditions

    International Nuclear Information System (INIS)

    Safety research sponsored by the Nuclear Regulatory Commission, Division of Reactor Safety Research, has resulted in notable advances in several areas of importance in the safety evaluation of reactor primary systems under normal operations and accident situations. First, the methods of linear elastic fracture mechanics and of elastic plastic fracture mechanics have been validated for prediction of pressure vessel performance by the Intermediate Vessel Test program results at the Oak Ridge National Laboratory. The ability confidently to predict vessel performance under realistic service conditions has permitted development of the computer program OCTAVIA which computes failure curves for a range of flaw sizes in terms of pressure and temperature for specified presure vessel material at specific neutron fluence levels. It then considers the probability of occurrence of flaw sizes and magnitude of pressure during an operational, overpressurization transient and determines the probability of failure, for both individual flaw sizes and for the full spectrum. This advance has been verified by the confirmatory results of testing small thick-walled cylinders under thermal shock conditions in the Heavy Section Steel Technology program, and of warm prestressing tests at the US Navel Research Laboratory. Thirdly, the technology of crack arrest has reached a level wherein standardization of test specimens and testing methods is now possible and, indeed, is underway. (Auth.)

  9. Water reactor fuel behaviour and fission products release in off-normal and accident conditions

    International Nuclear Information System (INIS)

    The present meeting was scheduled by the International Atomic Energy Agency upon the proposal of the Members of the International Working Group on Water Reactor Fuel Performance and Technology and held at the IAEA Headquarters in Vienna from 10 to 13 November 1986. Thirty participants from 17 countries and an international organization attended the meeting. Eighteen papers were presented from 13 countries and one international organization. The meeting was composed of four sessions and covered subjects related to: physico-chemical properties of core materials under off-normal conditions, and their interactions up to and after melt-down (5 papers); core materials deformation, relocation and core coolability under (severe) accident conditions (4 papers); fission products release: including experience, mechanisms and modelling (5 papers); power plant experience (4 papers). A separate abstract was prepared for each of these 18 papers. Four working groups covering the above-mentioned topics were held to discuss the present status of the knowledge and to develop recommendations for future activities in this field. Refs, figs and tabs

  10. Radioactive particulate release associated with the DOT specification 6M container under hypothetical accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, J.M.; Raney, P.J.

    1986-02-01

    A testing program was conducted to determine the leakage of depleted uranium dioxide powder (DUO) from the inner containment components of the US Department of Transportation's (DOT) specification 6M container under hypothetical accident conditions. Depleted uranium dioxide was selected as a surrogate for plutonium oxide because of the similarities in the powder characteristics, density and particle size, and because of the special handling and special facilities required for plutonium oxide. The DUO was packaged inside food pack cans in three different configurations inside the 2R vessel of the 6M container. The amount of DUO powder leakage ranged from none detectable (<2 x 10/sup -7/ g) to a high of 1 x 10/sup -3/ g. The combination of gravity, vibration and pressure produced the highest leakage of DUO. Containers that had hermetic seals (leak rates <6 x 10/sup -4/ atm cc/min) did not leak any detectable amount (<2 x 10/sup -7/ g) of DUO under the test conditions. Impact forces had no effect on the leakage of particles with the packaging configurations used. 23 refs., 24 figs., 3 tabs.

  11. Silicon Carbide Behaviour Under Prototypic LWR Chemistry/Neutron Flux and Accident Conditions

    International Nuclear Information System (INIS)

    The Accident Tolerant Fuels (ATF) programme was started with the goal of finding alternative fuel and cladding materials that perform as well as or better than current materials under normal operating conditions with enhanced performance during accidents. SiC has been a long-time candidate for this programme. Here we will discuss both out-of-core and in-core test results that are incorporated into analytical models developed at MIT. Out-of-core research has subjected un- irradiated SiC ceramic matrix composite (CMC) samples to a series of tests to gauge performance in a loss-of-coolant accident (LOCA). Previous work by the group with monolithic ot SiC has exposed samples to steam temperatures up to 1,500°C for 8 to 48 hours at various steam flow rates. Additionally, monolith samples have been quenched from up to 1,300°C into both room temperature and saturated water at atmospheric pressure. Following this testing, burst testing was performed to quantify strength degradation and ceramographic analysis was completed to determine microstructural effects. Using the same techniques as this previous monolithic work, testing of tube samples composed of three integrated layers have been tested. The three layers are an outer environmental barrier, a ceramic matrix composite, and an inner monolith layer; all layers are composed of SiC. These SiC/SiC CMC samples have been exposed to 1,400°C steam at ~6 g/min for 48 hours. Quench testing was performed from 1,200°C into saturated water to simulate the condition of reflood water after a LOCA, and burst and ceramographic analysis performed. Several different architectures of the CMC layer are in the process of being tested. Initial results for one CMC architecture indicate that the CMC samples exhibit the expected low oxidation rate of SiC in steam, and improved burst performance of both quenched and as-received samples. In the future two additional fibre architectures and sealed tubes will be examined, with the results being

  12. Generation IV benchmarking of TRISO fuel performance models under accident conditions: Modeling input data

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

    2014-09-01

    This document presents the benchmark plan for the calculation of particle fuel performance on safety testing experiments that are representative of operational accidental transients. The benchmark is dedicated to the modeling of fission product release under accident conditions by fuel performance codes from around the world, and the subsequent comparison to post-irradiation experiment (PIE) data from the modeled heating tests. The accident condition benchmark is divided into three parts: the modeling of a simplified benchmark problem to assess potential numerical calculation issues at low fission product release; the modeling of the AGR-1 and HFR-EU1bis safety testing experiments; and, the comparison of the AGR-1 and HFR-EU1bis modeling results with PIE data. The simplified benchmark case, thereafter named NCC (Numerical Calculation Case), is derived from ''Case 5'' of the International Atomic Energy Agency (IAEA) Coordinated Research Program (CRP) on coated particle fuel technology [IAEA 2012]. It is included so participants can evaluate their codes at low fission product release. ''Case 5'' of the IAEA CRP-6 showed large code-to-code discrepancies in the release of fission products, which were attributed to ''effects of the numerical calculation method rather than the physical model''[IAEA 2012]. The NCC is therefore intended to check if these numerical effects subsist. The first two steps imply the involvement of the benchmark participants with a modeling effort following the guidelines and recommendations provided by this document. The third step involves the collection of the modeling results by Idaho National Laboratory (INL) and the comparison of these results with the available PIE data. The objective of this document is to provide all necessary input data to model the benchmark cases, and to give some methodology guidelines and recommendations in order to make all results suitable for comparison

  13. Key factors affecting urban runoff pollution under cold climatic conditions

    Science.gov (United States)

    Valtanen, Marjo; Sillanpää, Nora; Setälä, Heikki

    2015-10-01

    Urban runoff contains various pollutants and has the potential of deteriorating the quality of aquatic ecosystems. In this study our objective is to shed light on the factors that control the runoff water quality in urbanized catchments. The effects of runoff event characteristics, land use type and catchment imperviousness on event mass loads (EML) and event mean concentrations (EMC) were studied during warm and cold periods in three study catchments (6.1, 6.5 and 12.6 ha in size) in the city of Lahti, Finland. Runoff and rainfall were measured continuously for two years at each catchment. Runoff samples were taken for total nutrients (tot-P and tot-N), total suspended solids (TSS), heavy metals (Zn, Cr, Al, Co, Ni, Cu, Pb, Mn) and total organic carbon (TOC). Stepwise multiple linear regression analysis (SMLR) was used to identify general relationships between the following variables: event water quality, runoff event characteristics and catchment characteristics. In general, the studied variables explained 50-90% of the EMLs but only 30-60% of the EMCs, with runoff duration having an important role in most of the SMLR models. Mean runoff intensity or peak flow was also often included in the runoff quality models. Yet, the importance (being the first, second or third best) and role (negative or positive impact) of the explanatory variables varied between the cold and warm period. Land use type often explained cold period concentrations, but imperviousness alone explained EMCs weakly. As for EMLs, the influence of imperviousness and/or land use was season and pollutant dependent. The study suggests that pollutant loads can be - throughout the year - adequately predicted by runoff characteristics given that seasonal differences are taken into account. Although pollutant concentrations were sensitive to variation in seasonal and catchment conditions as well, the accurate estimation of EMCs would require a more complete set of explanatory factors than used in this

  14. Thermochemistry of Ruthenium Oxyhydroxide Species and Their Impact on Volatile Speciations in Severe Nuclear Accident Conditions.

    Science.gov (United States)

    Miradji, Faoulat; Virot, François; Souvi, Sidi; Cantrel, Laurent; Louis, Florent; Vallet, Valérie

    2016-02-01

    Literature thermodynamic data of ruthenium oxyhydroxides reveal large uncertainties in some of the standard enthalpies of formation, motivating the use of high-level relativistic correlated quantum chemical methods to reduce the level of discrepancies. Reaction energies leading to the formation of all possible oxyhydroxide species RuOx(OH)y(H2O)z have been calculated for a series of reactions combining DFT (TPSSh-5%HF) geometries and partition functions, CCSD(T) energies extrapolated to the complete basis set limits. The highly accurate ab initio thermodynamic data were used as input data of thermodynamic equilibrium computations to derive the speciation of gaseous ruthenium species in the temperature, pressure and concentration conditions of severe nuclear accidents occurring in pressurized water reactors. At temperatures lower than 1000 K, gaseous ruthenium tetraoxide is the dominating species, between 1000 and 2000 K ruthenium trioxide becomes preponderant, whereas at higher temperatures gaseous ruthenium oxide, dioxide and even Ru in gaseous phase are formed. Although earlier studies predicted the formation of oxyhydroxides in significant quantities, the use of highly accurate ab initio thermodynamic data for ruthenium gaseous species leads to a more reliable inventory of gaseous ruthenium species in which gaseous oxyhydroxide ruthenium molecules are formed only in negligible amounts. PMID:26789932

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

    International Nuclear Information System (INIS)

    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.)

  16. High burnup (41 - 61 GWd/tU) BWR fuel behavior under reactivity initiated accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Takehiko; Kusagaya, Kazuyuki; Yoshinaga, Makio; Uetsuka, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-12-01

    High burnup boiling water reactor (BWR) fuel was pulse irradiated in the Nuclear Safety Research Reactor (NSRR) to investigate fuel behavior under cold startup reactivity initiated accident (RIA) conditions. Temperature, deformation, failure, and fission gas release behavior under the simulated RIA condition was studied in the tests. Fuel failure due to pellet-cladding mechanical interaction (PCMI) did not occur in the tests with typical domestic BWR fuel at burnups up to 56 GWd/tU, because they had limited cladding embrittlement due to hydrogen absorption of about 100 ppm or less. However, the cladding failure occurred in tests with fuel at a burnup of 61 GWd/tU, in which the peak hydrogen content in the cladding was above 150 ppm. This type of failure was observed for the first time in BWR fuels. The cladding failure occurred at fuel enthalpies of 260 to 360 J/g (62 to 86 cal/g), which were higher than the PCMI failure thresholds decided by the Japanese Nuclear Safety Commission. From post-test examinations of the failed fuel, it was found that the crack in the BWR cladding progressed in a manner different from the one in PWR cladding failed in earlier tests, owing to its more randomly oriented hydride distribution. Because of these differences, the BWR fuel was judged to have failed at hydrogen contents lower than those of the PWR fuel. Comparison of the test results with code calculations revealed that the PCMI failure was caused by thermal expansion of pellets, rather than by the fission gas expansion in the pellets. The gas expansion, however, was found to cause large cladding hoop deformation later after the cladding temperature escalated. (author)

  17. Containment severe accident thermohydraulic phenomena

    International Nuclear Information System (INIS)

    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)

  18. Radionuclide releases from UO2 and MOX fuel under severe accident conditions

    International Nuclear Information System (INIS)

    Radionuclide release from fuel under severe accident conditions was investigated in VEGA (Verification Experiments of radionuclides Gas/Aerosol release) program at Japan Atomic Energy Agency (JAEA). This study compares the results of tests on PWR-UO2 fuel, BWR-UO2 fuel and ATR (Advanced Thermal Reactor)-MOX(mixed oxide) fuel. The three types of fuels have burnup of 47, 56 and 43 GWd/t, respectively. Each fuel without cladding was set in a tungsten crucible and heated up to about 3130 K in helium atmosphere at 0.1 MPa. The fuel temperature was kept constant for 10 to 20 minuets at four plateaus during the heat up. The total fractional releases of high volatile Cs were 100% for the PWR-UO2 fuel, 97% for the BWR-UO2 fuel and 97% for the ART-MOX fuel. The Cs release with the heatup was different among three fuels for the temperature range below 2310 K, while the difference became small for the higher temperature range. The difference for the lower temperature range is considered to be caused by difference of irradiation histories, which varies migration states of the high volatile element. The total fractional releases of Mo and U were in the order of 0.1% and those of Sr and Pu were in the order of 1% both the tests with the BWR-UO2 and the ATR-MOX fuels. Release of low volatiles, U, Pu, Sr and Mo were dependent strongly on their chemical states, suggesting that vaporization was the controlling process. Namely, release of Pu and Sr was enhanced by the reduction of oxide, while it was largely decreased for Mo even at higher temperatures in the same atmosphere. (author)

  19. Behavior of small-sized BWR fuel under reactivity initiated accident conditions

    International Nuclear Information System (INIS)

    The present work was performed on this small-sized BWR fuel, where Zr liner and rod prepressurization were taken as experimental parameters. Experiment was done under simulated reactivity initiated accident (RIA) conditions at Nuclear Safety Research Reactor (NSRR) belonged to Japan Atomic Energy Research Institute (JAERI). Major remarks obtained are as follows: (1) Three different types of the fuel rods consisted of (a) Zr lined/pressurized (0.65MPa), (b) Zr lined/non-pressurized and (c) non-Zr lined/pressurized (o.65MPa) were used, respectively. Failure thresholds of these were not less than that (260 cal/g·fuel) described in Japanese RIA Licensing Guideline. Small-sized BWR and conventional 8 x 8 BWR fuels were considered to be in almost the same level in failure threshold. Failure modes of the three were (a) cladding melt/brittle, (b) cladding melt/brittle and (c) rupture by large ballooning, respectively. (2) The magnitude of pressure pulse at fuel fragmentation was also studied by lined/pressurized and non-lined/pressurized fuels. Above the energy deposition of 370 cal/g·fuel, mechanical energy (or pressure) was found to be released from these fragmented fuels. No measurable difference was, however, observed between the tested fuels and NSRR standard (and conventional 8 x 8 BWR) fuels. (3) It is worthy of mentioning that Zr liner tended to prevent the cladding from large ballooning. Non-lined/pressurized fuel tended to cause wrinkle deformation at cladding. Hence, cladding external was notched much by the wrinkles. (4) Time to fuel failure measured from the tested BWR fuels (pressurization < 0.6MPA) was longer than that measured from PWR fuels (pressurization < 3.2MPa). The magnitude of the former was of the order of 3 ∼ 6s, while that of the latter was < 1s. (J.P.N.)

  20. Response Analysis on Electrical Pulses under Severe Nuclear Accident Temperature Conditions Using an Abnormal Signal Simulation Analysis Module

    Directory of Open Access Journals (Sweden)

    Kil-Mo Koo

    2012-01-01

    Full Text Available Unlike design basis accidents, some inherent uncertainties of the reliability of instrumentations are expected while subjected to harsh environments (e.g., high temperature and pressure, high humidity, and high radioactivity occurring in severe nuclear accident conditions. Even under such conditions, an electrical signal should be within its expected range so that some mitigating actions can be taken based on the signal in the control room. For example, an industrial process control standard requires that the normal signal level for pressure, flow, and resistance temperature detector sensors be in the range of 4~20 mA for most instruments. Whereas, in the case that an abnormal signal is expected from an instrument, such a signal should be refined through a signal validation process so that the refined signal could be available in the control room. For some abnormal signals expected under severe accident conditions, to date, diagnostics and response analysis have been evaluated with an equivalent circuit model of real instruments, which is regarded as the best method. The main objective of this paper is to introduce a program designed to implement a diagnostic and response analysis for equivalent circuit modeling. The program links signal analysis tool code to abnormal signal simulation engine code not only as a one body order system, but also as a part of functions of a PC-based ASSA (abnormal signal simulation analysis module developed to obtain a varying range of the R-C circuit elements in high temperature conditions. As a result, a special function for abnormal pulse signal patterns can be obtained through the program, which in turn makes it possible to analyze the abnormal output pulse signals through a response characteristic of a 4~20 mA circuit model and a range of the elements changing with temperature under an accident condition.

  1. Mitigative techniques and analysis of generic site conditions for ground-water contamination associated with severe accidents

    International Nuclear Information System (INIS)

    The purpose of this study is to evaluate the feasibility of using ground-water contaminant mitigation techniques to control radionuclide migration following a severe commercial nuclear power reactor accident. The two types of severe commercial reactor accidents investigated are: (1) containment basemat penetration of core melt debris which slowly cools and leaches radionuclides to the subsurface environment, and (2) containment basemat penetration of sump water without full penetration of the core mass. Six generic hydrogeologic site classifications are developed from an evaluation of reported data pertaining to the hydrogeologic properties of all existing and proposed commercial reactor sites. One-dimensional radionuclide transport analyses are conducted on each of the individual reactor sites to determine the generic characteristics of a radionuclide discharge to an accessible environment. Ground-water contaminant mitigation techniques that may be suitable, depending on specific site and accident conditions, for severe power plant accidents are identified and evaluated. Feasible mitigative techniques and associated constraints on feasibility are determined for each of the six hydrogeologic site classifications. The first of three case studies is conducted on a site located on the Texas Gulf Coastal Plain. Mitigative strategies are evaluated for their impact on contaminant transport and results show that the techniques evaluated significantly increased ground-water travel times. 31 references, 118 figures, 62 tables

  2. Modelling of cladding oxidation by air under severe accident conditions with the MAAP 4 code

    International Nuclear Information System (INIS)

    In a nuclear power plant, air ingress into the vessel is a potential risk in some low probable situations of severe accidents. Air is a highly oxidizing atmosphere that can lead to an enhanced core oxidation and degradation affecting the release of FP. This is particularly true speaking about ruthenium release, which can be significantly increased in the presence of air. This is a key issue due to the high radio-toxicity of ruthenium and its ability to form highly volatile oxides. The oxygen affinity is decreasing in priority from the Zircaloy cladding, to fuel and ruthenium inclusions. It is consequently of great need to understand the phenomena governing cladding oxidation by air as a prerequisite for the source term issues in such scenarios. As a first step, a phenomenological study has been carried out to characterize nitriding of the Zircaloy claddings. In summary, nitriding occurs preferentially when the oxygen has been consumed locally or in case of total oxygen starvation and when the cladding was slightly pre-oxidized. Just like oxidation, nitriding can be modeled in a simplified form as a cladding weight gain in terms of thickness. The model implemented in MAAP takes this into account as well as re-oxidation of the nitrides, in the case where oxygen is available again (especially during a reflood). Several correlations were thus integrated and a new one, called “KIT-EDF”, was developed, based on KIT separate-effect tests. The model has been implemented and validated against QUENCH-16 and QUENCH-10 experiments, studying the oxidation in air atmosphere of an assembly pre-oxidized in steam and finally quenched with water. The simulations give encouraging results since the modeling of nitriding effects has increased hydrogen production during reflood, as experimentally observed. The results of this study lead us to identify a number of perspectives for the future, namely taking into account the changes in the structure of the oxide layer during a

  3. Development of Instrument Transmitter Protecting Device against High-Temperature Condition during Severe Accidents

    Directory of Open Access Journals (Sweden)

    Min Yoo

    2014-01-01

    Full Text Available Reliable information through instrumentation systems is essential in mitigating severe accidents such as the one that occurred at the Fukushima Daiichi nuclear power plant. There are five elements which might pose a potential threat to the reliability of parameter detection at nuclear power plants during a severe accident: high temperature, high pressure, high humidity, high radiation, and missiles generated during the evolution of a severe accident. Of these, high temperature apparently poses the most serious threat, since thin shielding can get rid of pressure, humidity, radiation (specifically, alpha and beta radiations, and missile effects. In view of this fact, our study focused on designing an instrument transmitter protecting device that can eliminate the high-temperature effect on transmitters to maintain their functional integrity. We present herein a novel concept for designing such a device in terms of heat transfer model that takes into account various heat transfer mechanisms associated with the device.

  4. Study on safety evaluation for nuclear fuel cycle facility under fire accident conditions

    International Nuclear Information System (INIS)

    Hot test at Rokkasho Reprocessing plant has been started since last year. In addition, construction of the MOX fuel fabrication facility at Rokkasho site is planning. So, the importance of safety evaluation of the nuclear fuel cycle facility is increasing. Under the fire accident, one of the serious postulated accidents in the nuclear fuel cycle facility, the equipments (glove-box, ventilation system, ventilation filters etc.) for the confinement of the radioactive materials within the facility could be damaged by a large amount of heat and smoke released from the combustion source. Therefore, the fundamental data and models calculating for the amount of heat and smoke released from the combustion source under such accident are important for the safety evaluation of the facility. In JAERI, the study focused on the evaluation of amount of heat and smoke released from the combustion source is planning. In this paper, the outline of experimental apparatus, measurement items and evaluation terms are described. (author)

  5. How to identify the key factors that affect driver perception of accident risk. A comparison between Italian and Spanish driver behavior.

    Science.gov (United States)

    de Oña, Juan; de Oña, Rocio; Eboli, Laura; Forciniti, Carmen; Mazzulla, Gabriella

    2014-12-01

    Road crashes can be caused by different factors, including infrastructure, vehicles, and human variables. Many research studies have focused solely on identifying the key factors that cause road crashes. From these studies, it emerged that human factors have the most relevant impact on accident severity. More specifically, accident severity depends on several factors related directly to the driver, i.e., driving experience, driver's socio-economic characteristics, and driving behavior and attitudes. In this paper, we investigate driver behaviors and attitudes while driving and specifically focus on different methods for identifying the factors that most affect the driver's perception of accident risk. To this end, we designed and conducted a survey in two different European contexts: the city of Cosenza, which is located in the south of Italy, and the city of Granada, which is located in the south of Spain. Samples of drivers were contacted for their opinions on certain aspects of driving rules and attitudes while driving, and different types of questions were addressed to the drivers to assess their judgments of these aspects. Consequently, different methods of data analysis were applied to determine the aspects that heavily influence driver perception of accident risk. An experiment based on the stated preferences (SP) was carried out with the drivers, and the SP data were analyzed using an ordered probit (OP) model. Interesting findings emerged from different analyses of the data and from the comparisons among the data collected in the two different territorial contexts. We found that both Italian and Spanish drivers consider driving in an altered psychophysical state and violating the overtaking rules to be the most risky behaviors. PMID:25247553

  6. Accident scenario diagnostics with neural networks

    International Nuclear Information System (INIS)

    Nuclear power plants are very complex systems. The diagnoses of transients or accident conditions is very difficult because a large amount of information, which is often noisy, or intermittent, or even incomplete, need to be processed in real time. To demonstrate their potential application to nuclear power plants, neural networks axe used to monitor the accident scenarios simulated by the training simulator of TVA's Watts Bar Nuclear Power Plant. A self-organization network is used to compress original data to reduce the total number of training patterns. Different accident scenarios are closely related to different key parameters which distinguish one accident scenario from another. Therefore, the accident scenarios can be monitored by a set of small size neural networks, called modular networks, each one of which monitors only one assigned accident scenario, to obtain fast training and recall. Sensitivity analysis is applied to select proper input variables for modular networks

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

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

  8. Current status of research on FBR fuel behavior under accident conditions and the relevant NSRR program plan

    International Nuclear Information System (INIS)

    In the situation that the development of demonstration FBR is being materialized, a substantial research on safety of core fuels under accident conditions is required as the part of the research and development program. The experimental study of fuel integrity against over power accidents etc. and failure behavior is important to establish a criteria for safety evaluation of FBR's. In this report, the scope of the program which is planned in NSRR is shown after reviewing other related experiments and examining the research region left undone. Major in-core experiments on fuel failure are surveyed wide in the view point of experimental region and the inquired results are summarized. Subsequently, the items and methods due to the NSRR experiment program is discussed. The experimental facility plan and the results of preliminary analysis on the fuel energy deposition and temperature behavior are also introduced. (author)

  9. Preclosure radiological safety analysis for accident conditions of the potential Yucca Mountain Repository: Underground facilities

    International Nuclear Information System (INIS)

    This preliminary preclosure radiological safety analysis assesses the scenarios, probabilities, and potential radiological consequences associated with postulated accidents in the underground facility of the potential Yucca Mountain repository. The analysis follows a probabilistic-risk-assessment approach. Twenty-one event trees resulting in 129 accident scenarios are developed. Most of the scenarios have estimated annual probabilities ranging from 10-11/yr to 10-5/yr. The study identifies 33 scenarios that could result in offsite doses over 50 mrem and that have annual probabilities greater than 10-9/yr. The largest offsite dose is calculated to be 220 mrem, which is less than the 500 mrem value used to define items important to safety in 10 CFR 60. The study does not address an estimate of uncertainties, therefore conclusions or decisions made as a result of this report should be made with caution

  10. HTGR fuel elements operating conditions during accidents with abrupt power raise

    International Nuclear Information System (INIS)

    The necessity of the investigations for developing of HTGR fuel elements operability criteria, connected with the specific energy release values and the rates of its change in fuel is demonstrated in the paper on the example of the accident with positive reactivity increase at VGM reactor pebble bed compression as a result of seismic impact. It is shown, that the average fuel enthalpy over the core in this accident with the emergency protection failure may reach ∼24 Kj/g U02, and the maximum rate of its increase is about 0.14 Kj/g.s. It considerably exceeds the established limit of fuel enthalpy for LWR fuel elements. (author). 5 refs, 2 figs

  11. Rehabilitation of living conditions in territories contaminated by the Chernobyl accident: the ETHOS project.

    Science.gov (United States)

    Lochard, Jacques

    2007-11-01

    The ETHOS Project, supported by the radiation protection research program of the European Commission (EC), was implemented in the mid-1990's with the support of the Belarus authorities as a pilot project to initiate a new approach for the rehabilitation of living conditions in the contaminated territories of the Republic. This initiative followed a series of studies performed in the context of the EC Community of Independent States cooperation program to evaluate the consequences of the Chernobyl accident (1991-1995), which clearly brought to the fore that a salient characteristic of the situation in these territories was the progressive and general loss of control of the population on its daily life. Furthermore, due to the economic difficulties during the years following the breakdown of the USSR, the population was developing private production and, in the absence of know-how and adequate means to control the radiological quality of foodstuffs, the level of internal exposure was rising significantly. The aim of the project was primarily to involve directly the population wishing to stay in the territories in the day-to-day management of the radiological situation with the goal of improving their protection and their living conditions. It was based on clear ethical principles and implemented by an interdisciplinary team of European experts with specific skills in radiation protection, agronomy, social risk management, communication, and cooperation in complex situations, with the support of local authorities and professionals. In a first phase (1996-1999), the ETHOS Project was implemented in a village located in the Stolyn District in the southern part of Belarus. During this phase, a few tens of villagers were involved in a step-by-step evaluation of the local radiological situation to progressively regain control of their daily life. In a second phase (1999-2001), the ETHOS Project was extended to four other localities of the District with the objective to

  12. Proceedings of a specialist meeting on the behaviour of water reactor fuel elements under accident conditions

    International Nuclear Information System (INIS)

    The contributions of this meeting report experimental, numerical and research investigations on the oxidation behaviour of zircaloy in case of a loss-of-coolant accident (LOCA), analysis of the kinetics of the oxidation rate, very high temperature behaviour of fuel rod claddings (failure mechanics, ballooning), the interaction between cladding and fuel, the mechanical behaviour of zircaloy, etc. Numerous experimental and computer code analysis results are given

  13. Thermodynamic analysis of spent pyrochemical salts in the stored condition and in viable accident scenarios

    International Nuclear Information System (INIS)

    This study involves examining ''spent'' electrorefining (ER) salts in the form present after usage (as stored), and then after exposure to water in a proposed accident scenario. Additionally, the equilibrium composition of the salt after extended exposure to air was also calculated by computer modeling and those results are also presented herein. It should be noted that these salts are extremely similar to spent MSE salts from the Rocky Flats MSE campaigns using NaCl-KCl- MgCl2

  14. Uncertainties under emergency conditions in Hiroshima and Nagasaki in 1945 and Bikini accident in 1954

    Energy Technology Data Exchange (ETDEWEB)

    Nishiwaki, Y. [Universitaet Wien, Institut fuer Medizinische Physik, Vienna (Austria); Kawai, H. [Atomic Energy Research Institute of Kinki Univ., Osaka (Japan); Shono, N. [Hiroshima Jogakuin Univ., Hiroshima (Japan); Fujita, S. [Radiation Effects Research Foundation, Department of Statistics, Hiroshima (Japan); Matsuoka, H. [Japan Atomic Energy Research Institute, Earth Simulator Research and Development Center, Tokyo (Japan); Fujiwara, S. [Japan Nuclear Cycle Development Institute, Ibaraki (Japan); Hosoda, T. [Chiyoda Technol Corporation, Tokyo (Japan)

    2000-05-01

    In exploding an atomic bomb, in addition to ionizing radiation, strong non-ionizing radiation, such as infrared, ultraviolet light, visible light, electromagnetic pulse radiation, as well as heat and shock waves are produced. The survivors and those who visited Hiroshima immediately after the atomic bombing could have been subjected to a number of other possible noxious effects in addition to atomic radiation. Hospitals, laboratories, drugstores, pharmaceutical works, storehouses of chemicals, factories, etc. that were situated close to the hypocenter were all completely destroyed and various mutagenic, carcinogenic or teratogenic substances must have been released, many doctors, nurses and chemists were killed. There was no medical care and no food in the region of high dose exposure and the drinking water was contaminated. There would have been various possibilities of infection. Mental stress would also have been much higher in the survivors closer to the hypocenter. It is confusing which factor played a dominant role. In addition, there would be problems in accurately identifying the position of the exposed persons at the time of the atomic bombing and also in estimating the shielding factors. There may be considerable uncertainty in human memory under such conditions. It is also possible that there could have been a large storage of gasoline to be used for transportation of the army corps in Hiroshima. Therefore there is a possibility that various toxic substances, mutagenic or carcinogenic agents such as benzopyrene and other radiomimetic substances, chemical weapons (Yperit, Lewisite, etc.) could have been released from various facilities which were destroyed at the time of the atomic bombing. After the German surrender, in May 1945, it was reported in June, in Japan, that the USA might attempt landing on Japan mainland, and that they might be planning massive use of chemical weapons all over Japan on that occasion. Preparing for such case chemical officers

  15. Uncertainties under emergency conditions in Hiroshima and Nagasaki in 1945 and Bikini accident in 1954

    International Nuclear Information System (INIS)

    In exploding an atomic bomb, in addition to ionizing radiation, strong non-ionizing radiation, such as infrared, ultraviolet light, visible light, electromagnetic pulse radiation, as well as heat and shock waves are produced. The survivors and those who visited Hiroshima immediately after the atomic bombing could have been subjected to a number of other possible noxious effects in addition to atomic radiation. Hospitals, laboratories, drugstores, pharmaceutical works, storehouses of chemicals, factories, etc. that were situated close to the hypocenter were all completely destroyed and various mutagenic, carcinogenic or teratogenic substances must have been released, many doctors, nurses and chemists were killed. There was no medical care and no food in the region of high dose exposure and the drinking water was contaminated. There would have been various possibilities of infection. Mental stress would also have been much higher in the survivors closer to the hypocenter. It is confusing which factor played a dominant role. In addition, there would be problems in accurately identifying the position of the exposed persons at the time of the atomic bombing and also in estimating the shielding factors. There may be considerable uncertainty in human memory under such conditions. It is also possible that there could have been a large storage of gasoline to be used for transportation of the army corps in Hiroshima. Therefore there is a possibility that various toxic substances, mutagenic or carcinogenic agents such as benzopyrene and other radiomimetic substances, chemical weapons (Yperit, Lewisite, etc.) could have been released from various facilities which were destroyed at the time of the atomic bombing. After the German surrender, in May 1945, it was reported in June, in Japan, that the USA might attempt landing on Japan mainland, and that they might be planning massive use of chemical weapons all over Japan on that occasion. Preparing for such case chemical officers

  16. ANL proposal for investigaton of concepts for hydrogen control under LWR accident conditions

    International Nuclear Information System (INIS)

    A proposal for investigation of concepts for hydrogen control in degraded core LWR accidents which could release significant quantities of hydrogen to the containment building is presented. This proposed work includes studies on the combustion suppression mechanisms which would involve reaction kinetics experiments with addition of chemicals or ions to scavenge the intermediate (free-radical or other) combustion products. Several additives appear promising. Also several condensed-phase system concepts presently appear attractive for the longer-term hydrogen removal systems. The work would be complementary to other current programs on hydrogen control

  17. Criticality safety assessment of a TRIGA reactor spent fuel pool under accident conditions

    International Nuclear Information System (INIS)

    An overview paper on the criticality safety analysis of a pool type storage for a TRIGA spent fuel at the ''Jozef Stefan'' Institute in Ljubljana, Slovenia, is presented. It was shown in that subcriticality is not guaranteed for some postulated accidents (an earthquake with subsequent fuel rack disintegration resulting in contact fuel pitch). To mitigate this deficiency, a study was made about replacing a certain number of fuel elements in the rack with absorber rods in order to lower the probability for supercriticality to acceptable level. (author)

  18. Fission product release from UO/sub 2/ under LWR accident conditions: recent data compared with review values

    International Nuclear Information System (INIS)

    Studies of fission product release from commercial LWR fuel at temperatures up to 20000C in steam have shown that >50% of the Kr, I, and Cs may be released within 20 min. These data are in fairly good agreement with the results of a previous NRC review, but the influences of specific test/accident conditions other than temperature (which is the most important variable) on the behavior of these and other fission products are apparent. In particular, chemical effects related to the extent of cladding oxidation may dominate, as in the case of tellurium. 14 refs., 5 figs., 2 tabs

  19. Radiation conditions in the Oryol region territory impacted by radioactive contamination caused by the Chernobyl NPP accident

    Directory of Open Access Journals (Sweden)

    G. L. Zakharchenko

    2016-01-01

    Full Text Available Research objective is retrospective analysis of radiation conditions in the Oryol region during 1986- 2015 and assessment of efficacy of the carried out sanitary and preventive activities for population protection against radiation contamination caused by the Chernobyl NPP accident.Article materials were own memoirs of events participants, analysis of federal state statistic surveillance forms 3-DOZ across the Oryol region, f-35 “Data on patients with malignant neoplasms, f-12 “Report on MPI activities”. Risk assessment of oncological diseases occurrence is carried out on the basis of AAED for 1986- 2014 using the method of population exposure risk assessment due to long uniform man-made irradiation in small doses. Results of medical and sociological research of genetic, environmental, professional and lifestyle factors were obtained using the method of cancer patients’ anonymous survey. Data on "risk" factors were obtained from 467 patients hospitalized at the Budgetary Health Care Institution of the Oryol region “Oryol oncology clinic”; a specially developed questionnaire with 60 questions was filled out.The article employs the method of retrospective analysis of laboratory and tool research and calculation of dose loads on the Oryol region population, executed throughout the whole period after the accident.This article provides results of the carried out laboratory research of foodstuff, environment objects describing the radiation conditions in the Oryol region since the first days after the Chernobyl NPP accident in 1986 till 2015.We presented a number of activities aimed at liquidation of man-caused radiation accident consequences which were developed and executed by the experts of the Oryol region sanitary and epidemiology service in 1986-2015. On the basis of the above-stated one may draw the conclusions listed below. Due to interdepartmental interaction and active work of executive authorities in the Oryol region, the

  20. Ruthenium release modelling in air under severe accident conditions using the MAAP4 code

    Energy Technology Data Exchange (ETDEWEB)

    Beuzet, E.; Lamy, J.S. [EDF R and D, 1 avenue du General de Gaulle, F-92140 Clamart (France); Perron, H. [EDF R and D, Avenue des Renardieres, Ecuelles, F-77818 Moret sur Loing (France); Simoni, E. [Institut de Physique Nucleaire, Universite de Paris Sud XI, F-91406 Orsay (France)

    2010-07-01

    In a nuclear power plant (NPP), in some situations of low probability of severe accidents, an air ingress into the vessel occurs. Air is a highly oxidizing atmosphere that can lead to an enhanced core degradation affecting the release of Fission Products (FPs) to the environment (source term). Indeed, Zircaloy-4 cladding oxidation by air yields 85% more heat than by steam. Besides, UO{sub 2} can be oxidised to UO{sub 2+x} and mixed with Zr, which may lead to a decrease of the fuel melting temperature. Finally, air atmosphere can enhance the FPs release, noticeably that of ruthenium. Ruthenium is of particular interest for two main reasons: first, its high radiotoxicity due to its short and long half-life isotopes ({sup 103}Ru and {sup 106}Ru respectively) and second, its ability to form highly volatile compounds such as ruthenium gaseous tetra-oxide (RuO{sub 4}). Considering that the oxygen affinity decreases between cladding, fuel and ruthenium inclusions, it is of great need to understand the phenomena governing fuel oxidation by air and ruthenium release as prerequisites for the source term issues. A review of existing data on ruthenium release, controlled by fuel oxidation, leads us to implement a new model in the EDF version of MAAP4 severe accident code (Modular Accident Analysis Program). This model takes into account the fuel stoichiometric deviation and the oxygen partial pressure evolution inside the fuel to simulate its oxidation by air. Ruthenium is then oxidised. Its oxides are released by volatilisation above the fuel. All the different ruthenium oxides formed and released are taken into consideration in the model, in terms of their particular reaction constants. In this way, partial pressures of ruthenium oxides are given in the atmosphere so that it is possible to know the fraction of ruthenium released in the atmosphere. This new model has been assessed against an analytical test of FPs release in air atmosphere performed at CEA (VERCORS RT8). The

  1. Experiments to quantify airborne release from packages with dispersible radioactive materials under accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Martens, R.; Lange, F. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Schwertnergasse 1, 50667 Koeln (Germany); Koch, W.; Nolte, O. [Fraunhofer-Institut fuer Toxikologie und Experimentelle Medizin (ITEM), Nikolai-Fuchs-Str.1, 30625 Hannover (Germany)

    2005-07-01

    For transport or handling accidents involving packages with radioactive materials and the assessment of potential radiological consequences, for the review of current requirements of the IAEA Transport Regulations, and for their possible further development reliable release data following mechanical impact are required. Within this context a research project was carried out which extends the basis for a well-founded examination of the contemporary system of requirements of 'Low Specific Activity' (LSA)-type materials and allows for its further development where appropriate. This project comprises a prior system-analytical examination and an experimental programme aiming at improving the general physical understanding of the release process as well as the quantity and the characteristics of airborne released material for non-fixed dispersible LSA-II material upon mechanical impact. Impaction experiments applying small, medium and real sized specimens of different dispersible materials revealed that the release behaviour of dispersible powders strongly depends upon material properties, e.g. particle size distribution and cohesion forces. The highest experimentally determined release fraction of respirable mass (AED < 10 {mu}m) amounted to about 2 % and was obtained for 2 kg of un-contained easily dispersible pulverized fly ash (PFA). For larger un-contained PFA specimen the release fraction decreases. However, packaging containing powdery material substantially reduces the airborne release fraction. The measured airborne release fractions for a 200 l drum with Type A certificate containing PFA were about a factor of 50 to 100 lower than for un-contained material. For a drop height of 9 m the airborne release fraction amounted to about 4 x 10{sup -5}. This value should be applicable for most of transport and handling accidents with mechanical impact. For a metal container of Type IP-2 or better which contains powder masses of 100 kg or more this release

  2. The reaction between iodine and organic coatings under severe PWR accident conditions. An experimental parameter study

    Energy Technology Data Exchange (ETDEWEB)

    Hellmann, S.; Funke, F.; Greger, G.U.; Bleier, A.; Morell, W. [Siemens AG, Power Generation Group, Erlangen (Germany)

    1996-12-01

    An extensive experimental parameter study was performed on the deposition and on the resuspension kinetics in the reaction system iodine/organically coated surfaces. Both reactions in the gas phase and in the liquid phase were investigated and kinetic rate constants suitable for modelling were derived. Previous experimental studies on the reaction of iodine with organic coated surfaces were mostly limited to temperatures below 100{sup o}C. Thus, this parameter study aims at filling a gap and providing kinetic data on heterogeneous reactions with organic surfaces in the accident-relevant temperature range of 100-160{sup o}C. Two types of laboratory experiments carried out at Siemens/KWU using coatings representative for German power plants (epoxy-tape paint), namely gas phase tests and liquid phase tests. (author) 6 figs., 6 tabs., 5 refs.

  3. VICTORIA: A mechanistic model of radionuclide behavior in the reactor coolant system under severe accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Heames, T.J. (Science Applications International Corp., Albuquerque, NM (USA)); Williams, D.A.; Johns, N.A.; Chown, N.M. (UKAEA Atomic Energy Establishment, Winfrith (UK)); Bixler, N.E.; Grimley, A.J. (Sandia National Labs., Albuquerque, NM (USA)); Wheatley, C.J. (UKAEA Safety and Reliability Directorate, Culcheth (UK))

    1990-10-01

    This document provides a description of a model of the radionuclide behavior in the reactor coolant system (RCS) of a light water reactor during a severe accident. This document serves as the user's manual for the computer code called VICTORIA, based upon the model. The VICTORIA code predicts fission product release from the fuel, chemical reactions between fission products and structural materials, vapor and aerosol behavior, and fission product decay heating. This document provides a detailed description of each part of the implementation of the model into VICTORIA, the numerical algorithms used, and the correlations and thermochemical data necessary for determining a solution. A description of the code structure, input and output, and a sample problem are provided. The VICTORIA code was developed upon a CRAY-XMP at Sandia National Laboratories in the USA and a CRAY-2 and various SUN workstations at the Winfrith Technology Centre in England. 60 refs.

  4. The reaction between iodine and organic coatings under severe PWR accident conditions. An experimental parameter study

    International Nuclear Information System (INIS)

    An extensive experimental parameter study was performed on the deposition and on the resuspension kinetics in the reaction system iodine/organically coated surfaces. Both reactions in the gas phase and in the liquid phase were investigated and kinetic rate constants suitable for modelling were derived. Previous experimental studies on the reaction of iodine with organic coated surfaces were mostly limited to temperatures below 100oC. Thus, this parameter study aims at filling a gap and providing kinetic data on heterogeneous reactions with organic surfaces in the accident-relevant temperature range of 100-160oC. Two types of laboratory experiments carried out at Siemens/KWU using coatings representative for German power plants (epoxy-tape paint), namely gas phase tests and liquid phase tests. (author) 6 figs., 6 tabs., 5 refs

  5. Experimental analyses of iodine behavior under severe accident conditions with ART

    Energy Technology Data Exchange (ETDEWEB)

    Hidaka, A.; Sugimoto, J. [Japan Atomic Energy Res. Inst., Ibaraki (Japan); Igarashi, M. [Kawasaki Heavy Industries, Ltd., 4-25, 2-Chome, Minami-suna, Koto-ku, Tokyo, 136 (Japan); Hashimoto, K. [Nuclear Power Engineering Corporation, 17-1, 3-Chome, Toranomon, Minato-ku, Tokyo, 105 (Japan); Yoshino, T. [Toshiba Advanced System Corporation, 1-2-4 Isago Kawasaki-ku, Kawasaki-shi, Kanagawa-ken, 210 (Japan)

    1997-09-01

    The fission products (FP) behavior analysis code ART developed at JAERI simulates a FP transport and deposition in a reactor coolant system and containment during severe accidents. As part of the code development and verification, several experimental analyses have been conducted. In the JAERI`s WAVE experiment, the effect of nitrogen or steam carrier gases on the cesium iodide (CsI) behavior in piping was recently investigated. The ART analysis for nitrogen agreed with the experimental results by reflecting the detailed thermo-fluiddynamic calculation on the CsI aerosol behavior analysis. On the contrary, the analysis for steam did not agree well with the experimental results because observed enhancement of aerosol growth cannot be explained by existing models. Moreover, the newly developed empirical models on iodine chemistry in water were examined for the ACE/RTF 3B experiment. The analysis showed that those models have a fundamental analytical capability. (orig.).

  6. Angra 1 high burnup fuel behaviour under reactivity initiated accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Daniel de Souza; Silva, Antonio Teixeira e, E-mail: dsgomes@ipen.b, E-mail: teixeira@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The 16x16 NGF (Next Generation Fuel) fuel assembly, comprising of highly corrosive-resistant ZIRLO clad fuel rods, been replacing the current 16x16 Standard (16STD) fuel assembly in the Angra 1, a pressurized water reactor, with a net output of 626 MWe. The 16x16 NGF fuel assemblies are designed for a peak rod average burnup of up to 75 GWd/MTU, thus improving fuel utilization and reducing spent fuel storage issues. A design basis accident, the Reactivity Initiated Accident (RIA), became a concern for a further increase in burnup as the simulated RIA tests revealed a lower enthalpy threshold for fuel failure. Two fuel performance codes, FRAPCON and FRAPTRAN, were used to predict high burnup behavior of Angra 1, during an RIA. The maximum average linear fuel rating used was 17.62 KW/m. The FRAPCON 3.4 code was applied to simulate the steady-state performance of the 16 NGF fuel rods up to a burnup of 55 GWd/MTU. With FRAPTRAN-1.4 the fuel behavior was simulated for an RIA power pulse of 4.5 ms (FHWH), and enthalpy peak of 130 Cal/g. With FRAPCON-3.4, the corrosion and hydrogen pickup characteristics of the advanced ZIRLO clad fuel rods were added to the code by modifying the actual corrosion model for Zircaloy-4 through the multiplication of empirical factors, which were appropriate to each alloy, and by means of reducing the current hydrogen pickup fraction. (author)

  7. RAIM-A model for iodine behavior in containment under severe accident condition

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han Chul; Cho, Yeong Hun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-12-15

    Following a severe accident in a nuclear power plant, iodine is a major contributor to the potential health risks for the public. Because the amount of iodine released largely depends on its volatility, iodine's behavior in containment has been extensively studied in international programs such as International Source Term Programme-Experimental Program on Iodine Chemistry under Radiation (EPICUR), Organization for Economic Co-operation and Development (OECD)-Behaviour of Iodine Project, and OECD-Source Term Evaluation and Mitigation. Korea Institute of Nuclear Safety (KINS) has joined these programs and is developing a simplified, stand-alone iodine chemistry model, RAIM (Radio-Active Iodine chemistry Model), based on the IMOD methodology and other previous studies. This model deals with chemical reactions associated with the formation and destruction of iodine species and surface reactions in the containment atmosphere and the sump in a simple manner. RAIM was applied to a simulation of four EPICUR tests and one Radioiodine Test Facility test, which were carried out in aqueous or gaseous phases. After analysis, the results show a trend of underestimation of organic and molecular iodine for the gas-phase experiments, the opposite of that for the aqueous-phase ones, whereas the total amount of volatile iodine species agrees well between the experiment and the analysis result.

  8. Accidents - Chernobyl accident

    International Nuclear Information System (INIS)

    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.)

  9. Condition of organ of vision and free radical process parameters in liquidators of the Chernobyl accident

    International Nuclear Information System (INIS)

    84 liquidators of consequences of Chernobyl APS accident from the age of 28 to 58 were examined. The control group was made with 22 men from the age of 28 to 52. A certain increase of infringement of a transparency of lens without typical attributes of radiating cataract is revealed in the experimental group. Electrophysiological investigation (EPI) shows a certain reduction of amplitude of a wave ''a'' of macular electroretinogram (ERG) on green stimulus, amplitude of a main component and lengthening of an interpeak time interval of flicker ERG 10 Hz is revealed. These changes indicate the tendency to reduction of functional activity of a retina (first of all at a level of photoreceptors) in paramacular and in a smaller degree in peripheral zones among liquidators. The parameters of contrast sensitivity are definitely reduced in the experimental group for all stimuli on all spatial frequencies. Luminous and colour sensitivity to stimuli of different colour in the experimental group is definitely reduced in all central field of sight, but in paracentral zone the degree of reduction is higher. We investigated the parameters of oxidative stress in both groups. Definite increase of production of the reactive oxygen species and disbalance of a glutathione link of antioxidant protection are revealed. Authentic correlation dependences are revealed: moderate direct correlation - between a level of glutathione reductase and amplitude of a main component of flicker ERG 10 Hz, between a level of oxidized glutathione and interpeak time interval of flicker ERG 10 Hz, inverse correlation - between the level of oxidized glutathione and amplitude of a main component of flicker ERG 10 Hz. In view of large spontaneous activity of free radical processes in a retina in norm the received results can explain revealed changes of an organ of vision. (author)

  10. Performance evaluation of control room HVAC and air cleaning systems under accident conditions

    International Nuclear Information System (INIS)

    In light water reactors, control rooms and technical support centers must be designed to provide habitable environments in accordance with the requirements specified in General Design Criterion 19 of Appendix A, 10 CFR Part 50. Therefore, the effectiveness of HVAC and air cleaning system designs with respect to plant operator protection has to be evaluated by the system designer. Guidance for performing the analysis has been previously given in ANSI/ASME N509-1980 as well as in presentations at past Air Cleaning Conferences. The previous work is extended and the methodology used in a generic, interactive computer program that performs Main Control Room and Technical Support Center (TSC) habitability analyses for LWR nuclear power plants is presented. For given accident concentrations of radionuclides or hazardous gases in the outdoor air intakes and plant spaces surrounding the Main Control Room (or TSC), the program models the performance of the HVAC and air cleaning system designs, and determines control room (or TSC) contaminant concentrations and plant operator protection factors. Calculated or actual duct leakage, air cleaning efficiency, and airborne contamination are taken into account. Flexibility of the model allows for the representation of most control rooms (or TSC) and associated HVAC and air cleaning system conceptual designs that have been used by the US architect/engineers. The program replaced tedious calculations to determine the effects of HVAC ductwork and equipment leakage and permits (1) parametric analyses of various HVAC system design options early in the conceptual phase of a project, and (2) analysis of the effects of leakage test results on contaminant room concentrations, and therefore operator doses

  11. Study of Air Ingress Across the Duct During the Accident Conditions

    International Nuclear Information System (INIS)

    The goal of this project is to study the fundamental physical phenomena associated with air ingress in very high temperature reactors (VHTRs). Air ingress may occur due to a rupture of primary piping and a subsequent breach in the primary pressure boundary in helium-cooled and graphite-moderated VHTRs. Significant air ingress is a concern because it introduces potential to expose the fuel, graphite support rods, and core to a risk of severe graphite oxidation. Two of the most probable air ingress scenarios involve rupture of a control rod or fuel access standpipe, and rupture in the main coolant pipe on the lower part of the reactor pressure vessel. Therefore, establishing a fundamental understanding of air ingress phenomena is critical in order to rationally evaluate safety of existing VHTRs and develop new designs that minimize these risks. But despite this importance, progress toward development these predictive capabilities has been slowed by the complex nature of the underlying phenomena. The combination of inter-diffusion among multiple species, molecular diffusion, natural convection, and complex geometries, as well as the multiple chemical reactions involved, impose significant roadblocks to both modeling and experiment design. The project team will employ a coordinated experimental and computational effort that will help gain a deeper understanding of multiphased air ingress phenomena. This project will enhance advanced modeling and simulation methods, enabling calculation of nuclear power plant transients and accident scenarios with a high degree of confidence. The following are the project tasks: Perform particle image velocimetry measurement of multiphase air ingresses; and, Perform computational fluid dynamics analysis of air ingress phenomena.

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

    International Nuclear Information System (INIS)

    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)

  13. Study of Air Ingress Across the Duct During the Accident Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Yassin [Texas A & M Univ., College Station, TX (United States)

    2013-05-06

    The goal of this project is to study the fundamental physical phenomena associated with air ingress in very high temperature reactors (VHTRs). Air ingress may occur due to a rupture of primary piping and a subsequent breach in the primary pressure boundary in helium-cooled and graphite-moderated VHTRs. Significant air ingress is a concern because it introduces potential to expose the fuel, graphite support rods, and core to a risk of severe graphite oxidation. Two of the most probable air ingress scenarios involve rupture of a control rod or fuel access standpipe, and rupture in the main coolant pipe on the lower part of the reactor pressure vessel. Therefore, establishing a fundamental understanding of air ingress phenomena is critical in order to rationally evaluate safety of existing VHTRs and develop new designs that minimize these risks. But despite this importance, progress toward development these predictive capabilities has been slowed by the complex nature of the underlying phenomena. The combination of inter-diffusion among multiple species, molecular diffusion, natural convection, and complex geometries, as well as the multiple chemical reactions involved, impose significant roadblocks to both modeling and experiment design. The project team will employ a coordinated experimental and computational effort that will help gain a deeper understanding of multiphased air ingress phenomena. This project will enhance advanced modeling and simulation methods, enabling calculation of nuclear power plant transients and accident scenarios with a high degree of confidence. The following are the project tasks: Perform particle image velocimetry measurement of multiphase air ingresses; and, Perform computational fluid dynamics analysis of air ingress phenomena.

  14. CANSWEL-2: a computer model of the creep deformation of Zircaloy cladding under loss-of-coolant accident conditions

    International Nuclear Information System (INIS)

    The CANSWEL-2 code models cladding creep deformation under conditions relevant to a loss-of-coolant accident (LOCA) in a pressurised water reactor (PWR). It considers in detail the centre rod of a 3 x 3 nominally square array, taking into account azimuthal non-uniformities in cladding thickness and temperature, and the mechanical restraint imposed on contact with neighbouring rods. Any of the rods in the array may assume a non-circular shape. Models are included for primary and secondary creep, dynamic phase change and superplasticity when both alpha- and beta-phase Zircaloy are present. A simple treatment of oxidation strengthening is incorporated. Account is taken of the anisotropic creep behaviour of alpha-phase Zircaloy which leads to cladding bowing. The CANSWEL-2 model is used both as a stand-alone code and also as part of the LOCA analysis code MABEL-2. (author)

  15. Global estimates of fatal occupational accidents.

    Science.gov (United States)

    Takala, J

    1999-09-01

    Data on occupational accidents are not available from all countries in the world. Furthermore, underreporting, limited coverage by reporting and compensation schemes, and non-harmonized accident recording and notification systems undermine efforts to obtain worldwide information on occupational accidents. This paper presents a method and new estimated global figures of fatal accidents at work by region. The fatal occupational accident rates reported to the International Labour Office are extended to the total employed workforce in countries and regions. For areas not covered by the reported information, rates from other countries that have similar or comparable conditions are applied. In 1994, an average estimated fatal occupational accident rate in the whole world was 14.0 per 100,000 workers, and the total estimated number of fatal occupational accidents was 335,000. The rates are different for individual countries and regions and for separate branches of economic activity. In conclusion, fatal occupational accident figures are higher than previously estimated. The new estimates can be gradually improved by obtaining and adding data from countries where information is not yet available. Sectoral estimates for at least key economic branches in individual countries would further increase the accuracy.

  16. Khorasan wheat population researching (Triticum turgidum, ssp. Turanicum (McKey) in the minimum tillage conditions

    OpenAIRE

    Ikanović Jela; Popović Vera; Janković Snežana; Živanović Ljubiša; Rakić Sveto; Dončić Dalibor

    2014-01-01

    Khorasan wheat occupies a special place in the group of new-old cereals (Triticum turgidum, ssp. Turanicum McKey). It is an ancient species, native to eastern Persia, that is very close to durum wheat by morphological characteristics. Investigations were carried out in agro ecological conditions of the eastern Srem, with two wheat populations with dark and bright awns as objects of study. The following morphological and productive characteristics were inves...

  17. Framework for accident management

    International Nuclear Information System (INIS)

    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

  18. Assessing veld condition in the Kruger National Park using key grass species

    Directory of Open Access Journals (Sweden)

    W.S.W. Trollope

    1989-10-01

    Full Text Available Veld condition refers to the condition of the vegetation in relation to some functional characteristic. In the Kruger National Park important functional characteristics are the potential of the veld to produce grass forage and fuel and to resist soil erosion. Consequently a simplified technique based on 18 key grass species was developed for assessing veld conditon and monitoring the effects of wild life management practices like veld burning, development of watering points and culling. The technique has been specifically developed for use by wildlife managers and has the ability to indicate the potential of the veld to support bulk grazing animals, to carry a fire and to resist soil erosion.

  19. Ruthenium release modelling in air and steam atmospheres under severe accident conditions using the MAAP4 code

    International Nuclear Information System (INIS)

    Highlights: ► We developed a new modelling of fuel oxidation and ruthenium release in the EDF version of the MAAP4 code. ► We validated this model against some VERCORS experiments. ► Ruthenium release prediction quantitatively and qualitatively well reproduced under air and steam atmospheres. - Abstract: In a nuclear power plant (NPP), a severe accident is a low probability sequence that can lead to core fusion and fission product (FP) release to the environment (source term). For instance during a loss-of-coolant accident, water vaporization and core uncovery can occur due to decay heat. These phenomena enhance core degradation and, subsequently, molten materials can relocate to the lower head of the vessel. Heat exchange between the debris and the vessel may cause its rupture and air ingress. After lower head failure, steam and air entering in the vessel can lead to degradation and oxidation of materials that are still intact in the core. Indeed, Zircaloy-4 cladding oxidation is very exothermic and fuel interaction with the cladding material can decrease its melting temperature by several hundred of Kelvin. FP release can thus be increased, noticeably that of ruthenium under oxidizing conditions. Ruthenium is of particular interest because of its high radio-toxicity due to 103Ru and 106Ru isotopes and its ability to form highly volatile compounds, even at room temperature, such as gaseous ruthenium tetra-oxide (RuO4). It is consequently of great need to understand phenomena governing steam and air oxidation of the fuel and ruthenium release as prerequisites for the source term issues. A review of existing data on these phenomena shows relatively good understanding. In terms of oxygen affinity, the fuel is oxidized before ruthenium, from UO2 to UO2+x. Its oxidation is a rate-controlling surface exchange reaction with the atmosphere, so that the stoichiometric deviation and oxygen partial pressure increase. High temperatures combined with the presence of

  20. Which key properties controls the preferential transport in the vadose zone under transient hydrological conditions

    Science.gov (United States)

    Groh, J.; Vanderborght, J.; Puetz, T.; Gerke, H. H.; Rupp, H.; Wollschlaeger, U.; Stumpp, C.; Priesack, E.; Vereecken, H.

    2015-12-01

    % arrival time and potential key soil properties, site factors and boundary conditions will be presented in order to identify key properties which control the preferential transport in the vadose zone under transient hydrological conditions.

  1. CHF experiments under realistic severe accident condition for IVR-ERVC strategy

    International Nuclear Information System (INIS)

    This study describes critical heat flux (CHF) experiments using a 2-D curved test section with trisodium phosphate (TSP : Na3PO4) and boric acid (BA : H3BO5). The CHF values of TSP solution, BA solution, and TSP + BA solution were enhanced by as much as 50% for all experimental conditions except the condition of 150 mm radius with BA solution. The enhancement can be explained by wettability enhancement and decrease of bubble departure diameter. This CHF enhancement could provide additional thermal margin for the IVR-ERVC strategy. (author)

  2. Interpretation of test results performed with catalyst samples of passive autocatalytic recombiners (PAR) under realistic PWR severe accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Zeyen, Roland [European Commission Joint Research Centre, Saint-Paul-lez-Durance (France). Inst. for Energy (JRC/IE) de Cadarache; Payot, Frederic [Institut de Radioprotection et de Surete Nucleaire (IRSN), Saint-Paul-lez-Durance (France). Centre d' Etudes de Cadarache; Reinecke, Ernst-Arndt [Forschungszentrum Juelich GmbH (Germany). Inst. of Energy Research and Climate Research - Nuclear Waste Management and Reactor Safety (IEK-6)

    2013-06-15

    Passive Autocatalytic Recombiners (PAR) are used regularly in modern Pressurized Water Reactors as a particular feature in the event of severe accidents (core melting) accompanied by large releases of hydrogen into the reactor containment. One objective of the Phebus programme was to perform poisoning studies by inserting in the last test FPT3 a number of small recombiner coupons (30 x 30 mm) manufactured by among others AREVA-NP, NIS, AECL and IRSN/IRCELYON. The goal was to expose catalytic surfaces samples to the atmosphere of the Phebus model containment that collects fission products and aerosols released during the degradation of the Phebus FP pre-irradiated fuel bundle as representative as possible of a severe accidents, and in particular containing boron carbide resulting from the insertion of a B4C control rod into the small scale real irradiated fuel bundle. Before the Phebus FPT3 test, reference and qualification tests were performed in the H2PAR test facility at Cadarache in order to check if the coupon holding equipment was correctly designed with minimum thermal-hydraulic disturbance. The surface temperature of one coupon of each kind was measured by contact-miniature thermocouple during the experiment. This 'reference' temperature in the controlled H2PAR atmosphere was to be compared later to the temperatures reached in the Phebus FP conditions. The results coming from the coupon temperatures in FPT3 were quite un-expected. Therefore, supplementary small-scale tests were performed in the REKO-1 facility at Juelich to understand the relatively low temperatures and the particular behaviour of coupons coming from different manufacturers. (orig.)

  3. Operation behaviour of passive autocatalytic recombiners (PAR) for hydrogen mitigation in realistic containment conditions after a severe PWR accident

    Energy Technology Data Exchange (ETDEWEB)

    Zeyen, Roland [European Commission Joint Research Centre, Brussels (Belgium). Inst. for Energy (JRC/IE); Payot, Frederic [Institut de Radioprotection et de Surete Nucleaire (IRSN), Saint-Paul-Lez-Durance (France). Centre d' Etudes de Cadarache; Reinecke, Ernst-Arndt [Forschungszentrum Juelich (Germany). Inst. of Energy and Climate Research - Nuclear Waste Management and Reactor Safety (IEK-6)

    2012-11-01

    Passive Autocatalytic Recombiners (PAR) are used regularly in modern Pressurized Water Reactors as a particular feature in the event of severe accidents (core melting) accompanied by large releases of hydrogen into the reactor containment. One objective of the Phebus programme was to perform poisoning studies by inserting in the last test FPT3 a number of small recombiner coupons (30 x 30mm) manufactured by among others AREVANP, NIS, AECL and IRSN/IRCELYON. The goal was to expose catalytic surfaces samples to the atmosphere of the Phebus model containment that collects fission products and aerosols released during the degradation of the Phebus FP pre-irradiated fuel bundle as representative as possible of a severe accidents, and in particular containing boron carbide resulting from the insertion of a B4C control rod into the small scale real irradiated fuel bundle. Before the Phebus FPT3 test, reference and qualification tests were performed in the H2PAR test facility at Cadarache in order to check if the coupon holding equipment was correctly designed with minimum thermal-hydraulic disturbance. The surface temperature of one coupon of each kind was measured by contact-miniature thermocouple during the experiment. This ''reference'' temperature in the controlled H2PAR atmosphere was to be compared later to the temperatures reached in the Phebus FP conditions. The results coming from the coupon temperatures in FPT3 were quite un-expected: therefore it was thought that supplementary small-scale tests were needed (in 2010) to understand the relatively low temperatures and the particular behaviour of coupons coming from different manufacturers. The test results were supported and verified by dedicated code calculations. (orig.)

  4. Role of accident analysis in development of severe accident management guidance for multi-unit CANDU nuclear power plants

    International Nuclear Information System (INIS)

    This paper discusses the role of accident analysis in support of the development of Severe Accident Management Guidance for domestic CANDU reactors. In general, analysis can identify what types of challenges can be expected during accident progression but it cannot specify when and to what degree accident phenomena will occur. SAMG overcomes these limitations by monitoring the actual values of key plant indicators that can be used directly or indirectly to infer the condition of the plant and by establishing setpoints beyond which corrective action is required. Analysis can provide a means to correlate observed post-accident plant behavior against predicted behaviour to improve the confidence in and quality of accident mitigation decisions. (author)

  5. TRUMP-BD: A computer code for the analysis of nuclear fuel assemblies under severe accident conditions

    International Nuclear Information System (INIS)

    TRUMP-BD (Boil Down) is an extension of the TRUMP (Edwards 1972) computer program for the analysis of nuclear fuel assemblies under severe accident conditions. This extension allows prediction of the heat transfer rates, metal-water oxidation rates, fission product release rates, steam generation and consumption rates, and temperature distributions for nuclear fuel assemblies under core uncovery conditions. The heat transfer processes include conduction in solid structures, convection across fluid-solid boundaries, and radiation between interacting surfaces. Metal-water reaction kinetics are modeled with empirical relationships to predict the oxidation rates of steam-exposed Zircaloy and uranium metal. The metal-water oxidation models are parabolic in form with an Arrhenius temperature dependence. Uranium oxidation begins when fuel cladding failure occurs; Zircaloy oxidation occurs continuously at temperatures above 13000 degree F when metal and steam are available. From the metal-water reactions, the hydrogen generation rate, total hydrogen release, and temporal and spatial distribution of oxide formations are computed. Consumption of steam from the oxidation reactions and the effect of hydrogen on the coolant properties is modeled for independent coolant flow channels. Fission product release from exposed uranium metal Zircaloy-clad fuel is modeled using empirical time and temperature relationships that consider the release to be subject to oxidation and volitization/diffusion (''bake-out'') release mechanisms. Release of the volatile species of iodine (I), tellurium (Te), cesium (Ce), ruthenium (Ru), strontium (Sr), zirconium (Zr), cerium (Cr), and barium (Ba) from uranium metal fuel may be modeled

  6. Determination of transient radial-azimuthal temperature distributions in fuel bundles under loss-of-coolant-accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Saltos, N.T.; Christensen, R.N.; Aldemir, T.

    1988-10-01

    A methodology is presented to determine the transient temperature distributions in fuel bundles under loss-of-coolant accident (LOCA) conditions using a recently developed variational technique for the solution of radial-azimuthal heat conduction in the fuel rods and the modified view factor concept proposed by Uchida and Nakamure to model the radiative heat transfer between the rods. The variational technique is based on the Lebron-Labermont restricted variational principle and represents the temperature distribution in the rods at a given time during the LOCA via parabolic and circular trial functions in the radial and azimuthal directions, respectively. The methodology is implemented to a 4 x 4 boiling water reactor fuel bundle under typical LOCA conditions to investigate the effects of changes in rod heat transfer characteristics and simplifying modeling assumptions on predicted rod temperature distributions. The results show that these effects depend on the rod location in the assembly and LOCA phase under consideration and indicate that same degree of modelling detail may not be necessary for all the rods in the bundle at all times during the LOCA.

  7. Kinetics of iodine and cesium reactions in the CANDU reactor primary heat transport system under accident conditions

    International Nuclear Information System (INIS)

    Gas-phase reaction kinetics have been modelled for the release of cesium and iodine into steam and steam/hydrogen atmospheres. The conditions are those anticipated in a CANDU reactor fuel channel following some postulated loss-of-coolant accidents. A total of seventeen chemical species were used in the model, including all important cesium and iodine species. Reaction rate constants were taken from the literature, or calculated where possible, or estimated. The composition evolution of the system was calculated, following a burst release of cesium and iodine, as a function of total iodine and cesium concentrations, cesium/iodine release ratio, iodine release form (atomic I or CsI), fuel channel atmosphere, and radiolysis effects. In general, the calculation demonstrates that CsI and CsOH rapidly (-2 s) become the most important species in the system for virtually all conditions. Atomic I is found to be significant only for very low release concentrations, or for Cs:I ratios less than unity. The main body of the modelling was performed at 1000 K. Some calculations were also performed for a three-node temperature system - 1500 K, 1000 K and 750 K - with the fission products being transported from high to low temperature. Thus, a qualitative picture is provided of the evolution of the chemistry in the fuel channel as the fission products are swept out by the residual steam flow

  8. Strategies for operation of containment related ESFs in managing activity release to the environment during accident conditions

    International Nuclear Information System (INIS)

    In Indian PHWR design, a double containment concept with passive vapour suppression pool (to limit peak pressure) system has been adopted. In addition to it, various Engineered Safety Features (ESFs) have been incorporated to limit the release of radioactivity to the environment. They are: Reactor building emergency coolers for cooling which results in fast reduction of overpressure; Primary Containment Filtration and Pump Back System (PCFPBS) for reduction in iodine concentration inside RB atmosphere during post LOCA period; and, Primary Containment Controlled Discharge System (PCCDS) for the rapid reduction of over-pressure tail. Due to operation of secondary containment purge system, which maintain negative pressure in the annulus, the ground level release is negligibly small. However, if non- availability of negative pressure in secondary containment space is assumed, then operation of PCFPBS and PCCDS system reduces the ground level release significantly. In this situation, depending upon time of operation of the PCFPBS, it can effectively reduce the iodine release, both in stack level and ground level by trapping it in charcoal filters. It is seen that delay time of PCFPBS operation in conjunction with prevailing weather condition can be manipulated to reduce the effect of stack level release of iodine. In this paper the containment related ESFs used in Indian PHWR is discussed in brief and the effectiveness of operator actions and management strategies in actuation of the ESFs in reducing the activity release to environment (during postulated accident conditions) will be brought out. (author)

  9. FASTGRASS: A mechanistic model for the prediction of Xe, I, Cs, Te, Ba, and Sr release from nuclear fuel under normal and severe-accident conditions

    International Nuclear Information System (INIS)

    The primary physical/chemical models that form the basis of the FASTGRASS mechanistic computer model for calculating fission-product release from nuclear fuel are described. Calculated results are compared with test data and the major mechanisms affecting the transport of fission products during steady-state and accident conditions are identified

  10. Retention of iodine and other airborne radionuclides in nuclear facilities during abnormal and accident conditions

    International Nuclear Information System (INIS)

    Extensive research efforts have been undertaken in the world scientific community advancing the status of systems to maintain high air cleaning efficiency under the extreme abnormal conditions. The IAEA Co-ordinated Research Programme to upgrade technology in the area started in 1983 on the recommendations of a previous programme and the development covering a five year term is described in this document. Research laboratories from ten Member States participated, Belgium, German Democratic Republic, Hungary, India and Yugoslavia for three years with Austria, Canada, Federal Republic of Germany, Republic of Korea and UK for lesser periods. Research co-ordination meetings were held in Belgium (1984), Canada (1986) and Hungary (1988). A separate abstract was prepared for each of the 9 presentations from experts from the above mentioned Member States who participated in this research programme. Refs, figs and tabs

  11. Effects of temperature history during cooling process on cladding ductility reduction under lost of coolant accident conditions

    International Nuclear Information System (INIS)

    In a Loss-of-Coolant Accident (LOCA) of LWRs, heated fuel rods are quenched by water injected from the Emergency Core Cooling System. Existing analyses indicate that fuel rods are cooled slowly before the quench and the cooling rate at that stage depends on scenario of the accident. Microstructure can be different between fuel claddings quenched directly from high temperatures and those quenched after slow-cooling process. It has been suggested that ductility reduction is enhanced in the latter case. Although reduction in cladding ductility is important for reactor safety in a LOCA, the effects of cooling conditions on the cladding ductility reduction has not been sufficiently investigated and mechanism for the influence of cooling rate has not been clarified. In the present study, samples cut from non-irradiated 17x17-type Zircaloy-4 cladding tubes for PWRs were isothermally oxidized at 1373 and 1473 K, slowly cooled and then quenched, changing temperature at which quenching process is started and rate of the slow cooling. The oxidized and quenched samples were subjected to ring compression test in order to evaluate effects of the cooling conditions on the cladding ductility reduction. In addition, metallographic examination, Vickers hardness test and computer code analysis were conducted to examine the mechanisms. Due to oxidation, ZrO2 layer is formed at the cladding surface, oxygen-stabilized alpha phase layer is formed beneath the oxide layer, and oxygen concentration increases in the central metallic layer. As the metallic layer is cooled slowly from the isothermal oxidation temperatures, oxygen-rich α phase precipitates in the β phase layer. It was found out that reduction in cladding ductility strongly depends on area fraction of α phase region precipitated in the metallic layer. Both size and hardness of α-phase region are increased as the rate of the slow cooing decreases, while the area fraction is nearly constant. Accordingly, the reduction in

  12. Distribution of hydrogen within the HDR-containment under severe accident conditions. OECD standard problem. Final comparison report

    International Nuclear Information System (INIS)

    The present report summarizes the results of the International Standard Problem Exercise ISP-29, based on the HDR Hydrogen Distribution Experiment E11.2. Post-test analyses are compared to experimentally measured parameters, well-known to the analysis. This report has been prepared by the Institute for Reactor Dynamics and Reactor Safety of the Technical University Munich under contract with the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) which received funding for this activity from the German Ministry for Research and Technology (BMFT) under the research contract RS 792. The HDR experiment E11.2 has been performed by the Kernforschungszentrum Karlsruhe (KfK) in the frame of the project 'Projekt HDR-Sicherheitsprogramm' sponsored by the BMFT. Ten institutions from eight countries participated in the post-test analysis exercise which was focussing on the long-lasting gas distribution processes expected inside a PWR containment under severe accident conditions. The gas release experiment was coupled to a long-lasting steam release into the containment typical for an unmitigated small break loss-of-coolant accident. In lieu of pure hydrogen a gas mixture consisting of 15% hydrogen and 85% helium has been applied in order to avoid reaching flammability during the experiment. Of central importance are common overlay plots comparing calculated transients with measurements of the global pressure, the local temperature-, steam- and gas concentration distributions throughout the entire HDR containment. The comparisons indicate relatively large margins between most calculations and the experiment. Having in mind that this exercise was specified as an 'open post-test' analysis of well-known measured data the reasons for discrepancies between measurements and simulations were extensively discussed during a final workshop. It was concluded that analytical shortcomings as well as some uncertainties of experimental boundary conditions may be responsible for deviations

  13. What are the key conditions associated with lower limb amputations in a major Australian teaching hospital?

    Directory of Open Access Journals (Sweden)

    Lazzarini Peter A

    2012-05-01

    Full Text Available Abstract Background Lower extremity amputation results in significant global morbidity and mortality. Australia appears to have a paucity of studies investigating lower extremity amputation. The primary aim of this retrospective study was to investigate key conditions associated with lower extremity amputations in an Australian population. Secondary objectives were to determine the influence of age and sex on lower extremity amputations, and the reliability of hospital coded amputations. Methods Lower extremity amputation cases performed at the Princess Alexandra Hospital (Brisbane, Australia between July 2006 and June 2007 were identified through the relevant hospital discharge dataset (n = 197. All eligible clinical records were interrogated for age, sex, key condition associated with amputation, amputation site, first ever amputation status and the accuracy of the original hospital coding. Exclusion criteria included records unavailable for audit and cases where the key condition was unable to be determined. Chi-squared, t-tests, ANOVA and post hoc tests were used to determine differences between groups. Kappa statistics were used to measure reliability between coded and audited amputations. A minimum significance level of p  Results One hundred and eighty-six cases were eligible and audited. Overall 69% were male, 56% were first amputations, 54% were major amputations, and mean age was 62 ± 16 years. Key conditions associated included type 2 diabetes (53%, peripheral arterial disease (non-diabetes (18%, trauma (8%, type 1 diabetes (7% and malignant tumours (5%. Differences in ages at amputation were associated with trauma 36 ± 10 years, type 1 diabetes 52 ± 12 years and type 2 diabetes 67 ± 10 years (p  Conclusions This study, the first in over 20 years to report on all levels of lower extremity amputations in Australia, found that people undergoing amputation are more likely to be older, male and have

  14. Sensing controlled pulse key-holing condition in plasma arc welding

    Institute of Scientific and Technical Information of China (English)

    JIA Chuan-bao; WU Chuan-song; ZHANG Yu-ming

    2009-01-01

    According to the strategy of controlled pulse key-holing, a new sensing and control system was developed for monitoring and controlling the keyhole condition during plasma arc welding (PAW). Through sensing and processing the efflux plasma voltage signals, the quantitative relationship among the welding current, efflux plasma voltage and backside weld width of the weld was established. PAW experiments show that the efflux plasma voltage can reflect the state of keyhole and backside weld width accurately. The closed-loop control tests validate the stability and reliability of the developed keyhole PAW system.

  15. Understanding of Iodine Behavior Model Under Severe Accident Conditions in NPPs (I)

    International Nuclear Information System (INIS)

    Support from ISAAC code which is developed in Korea will be needed when a regulatory body (KINS) reviews Wolsong specific SAMG submitted by KHNP in late 2009. The SA research area can be divided into thermal hydraulic (T/H) and fission product (FP) areas and international evaluation shows an increasing opinion that past analysis has large uncertainty in the FP area. Using very small manpower (less than 0.5 MY for 3 year period (2007.3-2010.2)), this study reviewed EU results (BIP, ThAI) and ISAAC possibility for experiment simulation. As results, international and domestic technical status until early 2009 was investigated and input model modification based on these investigation was provided. Simulation possibility of EU experiments showed the Benchmark function in MAAP should be activated in ISAAC (by cooperation with MAAP developer, FAI) as a preliminary arrangement and independent model development reflecting those international results could be possible. This documentation will be referred from PHWR analysis for both source term and safety goal and will enhance the internal understanding for the necessity of iodine behavior study under SA conditions. FP (mainly iodine) model development in the next step using this study will contribute to keeping both improved quality and international competitiveness in ISAAC code

  16. Fission product release in conditions of a spent fuel pool severe accident

    International Nuclear Information System (INIS)

    Full text: Depending on the residence time, fuel burnup, and fuel rack configuration, there may be sufficient decay heat for the fuel clad to heat up, swell, and burst in case of a loss of pool water. Initiating event categories can be: loss of offsite power from events initiated by severe weather, internal fire, loss of pool cooling, loss of coolant inventory, seismic event, aircraft impact, tornado, missile attack. The breach in the clad releases the radioactive gases present in the gap between the fuel and clad, what is called 'gap release'. If the fuel continues to heat up, the zirconium clad will reach the point of rapid oxidation in air. This reaction of zirconium and air, or zirconium and steam is exothermic. The energy released from the reaction, combined with the fuel's decay energy, can cause the reaction to become self-sustaining and ignite the zirconium. The increase in heat from the oxidation reaction can also raise the temperature in adjacent fuel assemblies and propagate the oxidation reaction. Simultaneously, the sintered UO2 pellets resulting from pins destroying are oxidized. Due to the self-disintegration of pellets by oxidation, fission gases and low volatile fission products are released. The release rate, the chemical nature and the amount of fission products depend on powder granulation distribution and environmental conditions. The zirconium burning and pellets self-disintegration will result in a significant release of spent fuel fission products that will be dispersed from the reactor site. (author)

  17. Cloud conditions for low atmospheric electricity during disturbed period after the Fukushima nuclear accident

    Science.gov (United States)

    Yatagai, Akiyo; Yamauchi, Masatoshi; Ishihara, Masahito; Watanabe, Akira; Murata, Ken T.

    2016-04-01

    The vertical (downward) component of the atmospheric electric field, or potential gradient (PG) under cloud generally reflects the electric charge distribution in the cloud. The PG data at Kakioka, 150 km southwest of the Fukushima Dai-ichi Nuclear Power Plant (FNPP1) suggested that this relation can be modified when the radioactive dust was floating in the air, and the exact relation between the weather and this modification could lead to new insight in plasma physics in the wet atmosphere. Unfortunately the detailed weather data was not available above Kakioka (only the precipitation data was available). Therefore, estimation of the cloud condition during March 2011 was strongly needed. We have developed various meteorological information links (http://www.chikyu.ac.jp/akiyo/firis/) and original radar and precipitation data will be released from the page. Here we present various radar images that we have prepared for March 2011. We prepared three-dimensional radar reflectivity of the C-band radar of JMA in every 10 minutes over all Kanto Plain centered at Tokyo and Fukushima prefecture centered at Sendai. We have released images of each altitude (1km interval) for 15th - 16thand 21th March (http://sc-web.nict.go.jp/fukushima/). The vertical structure of the rainfall is almost the same at 4km with the surface and sporadic high precipitation is observed at 6 km height for 15-16th. While, generally precipitation pattern that is similar to the surface is observed at 5km height on 21th. On the other hand, an X-band radar centered at Fukushima university is also used to know more localized raindrop patterns at zenith angle of 4 degree. We prepared 10-minutes/120m mesh precipitation patterns for March 15th, 16th, 17th, 18th, 20th, 21th, 22th and 23th. Quantitative estimate is difficult from this X-band radar, but localized structure, especially for the rain-band along Nakadori (middle valley in Fukushima prefecture), that is considered to determine the highly

  18. Consideration of Command and Control Performance during Accident Management Process at the Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Nisrene M. [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Sok Chul [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    The accident at the Fukushima Daiichi nuclear power plants shifted the nuclear safety paradigm from risk management to on-site management capability during a severe accident. The kernel of on-site management capability during an accident at a nuclear power plant is situation awareness and agility of command and control. However, little consideration has been given to accident management. After the events of September 11, 2001 and the catastrophic Fukushima nuclear disaster, agility of command and control has emerged as a significant element for effective and efficient accident management, with many studies emphasizing accident management strategies, particularly man-machine interface, which is considered a key role in ensuring nuclear power plant safety during severe accident conditions. This paper proposes a conceptual model for evaluating command and control performance during the accident management process at a nuclear power plant. Communication and information processing while responding to an accident is one of the key issues needed to mitigate the accident. This model will give guidelines for accurate and fast communication response during accident conditions.

  19. Accidents at work and living conditions among solid waste segregators in the open dump of Distrito Federal

    OpenAIRE

    Maria da Graça Hoefel; Fernando Ferreira Carneiro; Leonor Maria Pacheco Santos; Muriel Bauerman Gubert; Elisa Maria Amate; Wallace dos Santos

    2013-01-01

    The work of recycling solid waste segregators allows a precarious livelihood, but triggers a disease process that exacerbates their health and well-being. This study aimed to estimate the prevalence of occupational accidents at the open dump in the Federal District and its associated factors. Most segregators have had an accident at work (55.5%), perceived the danger of their working environment (95.0%) and claimed they did not receive personal protective equipment (51.7%). Among other findin...

  20. Factors contributing to driver’s condition after fatal and injury vehicle accidents in North Khorasan province- New Year 1391

    Directory of Open Access Journals (Sweden)

    Javad Rezazadeh

    2013-01-01

    Full Text Available Abstract Background and Aim: Injuries from traffic accidents are a major public health problem, and the third leading cause of mortality in people aged 1 to 40 years. Each year 31.8 persons per hundred thousands of Iranians are killed in car accidents. Neighboring of North Khorasan province with Razavi Khorasan, a province with a lot of pilgrims caused a large number of passengers travel via North Khorasan province. This study aimed to evaluate the road accidents and its related factors in the city of bojnurd in March 2012. Materials and Methods: this cross-sectional study was done from … to … 2012(the New Year vacation in Iran. All injured or victims from car accidents who referred to the emergency department of the Imam Ali Hospital formed the research community. Data was gathered by a questionnaire consisting vehicle specification, driver and injured characteristics. For victims and those were not able to answer, we used the family members or relatives for gathering the data. All data analysis was done in SPSS version 19.Results: during the study period, 148 injured people were admitted to the hospital. Drivers’ mean age were 33.9 with the SD of 11.9 years; among them 43.2% were used seat belt. One driver and three passengers were killed immediately, and two drivers and three passengers died in the first 24 hours of admission. Fastening seat belt by drivers reduce the hospitalization rate significantly (p-value<0.0001. 50.7% of the accidents were head-on collisions. Violation from the speed limit (41.3%, indiscretions (25.4% and drowsiness were the most common causes of accident respectively. Conclusion: training the drivers, obligation for using seat belt by driver and passengers, rest after long hours driving , and more control of traffic police especially in two way roads could reduce the car accident or in case of accident help to prevent severe damage and injury.

  1. Accidents at work and living conditions among solid waste segregators in the open dump of Distrito Federal

    Directory of Open Access Journals (Sweden)

    Maria da Graça Hoefel

    2013-09-01

    Full Text Available The work of recycling solid waste segregators allows a precarious livelihood, but triggers a disease process that exacerbates their health and well-being. This study aimed to estimate the prevalence of occupational accidents at the open dump in the Federal District and its associated factors. Most segregators have had an accident at work (55.5%, perceived the danger of their working environment (95.0% and claimed they did not receive personal protective equipment (51.7%. Among other findings, 55.8% ate foods found in the trash, 50.0% experienced food insecurity at home and 44.8% received Bolsa Família. There was a statistically significant relationship between work accidents and perception of dangerous work environment, household food insecurity and the presence of fatigue, stress or sadness (p < 0.05. On the other hand, the fellowship between the segregators was associated with a lower prevalence of accidents (p < 0.006. Women are the majority of the segregators (56.5% and reported more accidents than men (p < 0.025. We conclude that the solid waste segregators constitute a vulnerable community, not only from the perspective of labor, but also from the social and environmental circumstances. To reverse this situation, effective implementation of the National Policy of Solid Wastes is imperative, in association with affirmative policies to grant economic emancipation for this population.

  2. Analyzing the causation of a railway accident based on a complex network

    International Nuclear Information System (INIS)

    In this paper, a new model is constructed for the causation analysis of railway accident based on the complex network theory. In the model, the nodes are defined as various manifest or latent accident causal factors. By employing the complex network theory, especially its statistical indicators, the railway accident as well as its key causations can be analyzed from the overall perspective. As a case, the “7.23” China—Yongwen railway accident is illustrated based on this model. The results show that the inspection of signals and the checking of line conditions before trains run played an important role in this railway accident. In conclusion, the constructed model gives a theoretical clue for railway accident prediction and, hence, greatly reduces the occurrence of railway accidents. (interdisciplinary physics and related areas of science and technology)

  3. Analyzing the causation of a railway accident based on a complex network

    Science.gov (United States)

    Ma, Xin; Li, Ke-Ping; Luo, Zi-Yan; Zhou, Jin

    2014-02-01

    In this paper, a new model is constructed for the causation analysis of railway accident based on the complex network theory. In the model, the nodes are defined as various manifest or latent accident causal factors. By employing the complex network theory, especially its statistical indicators, the railway accident as well as its key causations can be analyzed from the overall perspective. As a case, the “7.23” China—Yongwen railway accident is illustrated based on this model. The results show that the inspection of signals and the checking of line conditions before trains run played an important role in this railway accident. In conclusion, the constructed model gives a theoretical clue for railway accident prediction and, hence, greatly reduces the occurrence of railway accidents.

  4. VICTORIA: A mechanistic model of radionuclide behavior in the reactor coolant system under severe accident conditions. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Heams, T J [Science Applications International Corp., Albuquerque, NM (United States); Williams, D A; Johns, N A; Mason, A [UKAEA, Winfrith, (England); Bixler, N E; Grimley, A J [Sandia National Labs., Albuquerque, NM (United States); Wheatley, C J [UKAEA, Culcheth (England); Dickson, L W [Atomic Energy of Canada Ltd., Chalk River, ON (Canada); Osborn-Lee, I [Oak Ridge National Lab., TN (United States); Domagala, P; Zawadzki, S; Rest, J [Argonne National Lab., IL (United States); Alexander, C A [Battelle, Columbus, OH (United States); Lee, R Y [Nuclear Regulatory Commission, Washington, DC (United States)

    1992-12-01

    The VICTORIA model of radionuclide behavior in the reactor coolant system (RCS) of a light water reactor during a severe accident is described. It has been developed by the USNRC to define the radionuclide phenomena and processes that must be considered in systems-level models used for integrated analyses of severe accident source terms. The VICTORIA code, based upon this model, predicts fission product release from the fuel, chemical reactions involving fission products, vapor and aerosol behavior, and fission product decay heating. Also included is a detailed description of how the model is implemented in VICTORIA, the numerical algorithms used, and the correlations and thermochemical data necessary for determining a solution. A description of the code structure, input and output, and a sample problem are provided.

  5. Preclosure radiological safety analysis for accident conditions of the potential Yucca Mountain Repository: Underground facilities; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C.W.; Sit, R.C.; Zavoshy, S.J.; Jardine, L.J. [Bechtel National, Inc., San Francisco, CA (United States); Laub, T.W. [Sandia National Labs., Albuquerque, NM (United States)

    1992-06-01

    This preliminary preclosure radiological safety analysis assesses the scenarios, probabilities, and potential radiological consequences associated with postulated accidents in the underground facility of the potential Yucca Mountain repository. The analysis follows a probabilistic-risk-assessment approach. Twenty-one event trees resulting in 129 accident scenarios are developed. Most of the scenarios have estimated annual probabilities ranging from 10{sup {minus}11}/yr to 10{sup {minus}5}/yr. The study identifies 33 scenarios that could result in offsite doses over 50 mrem and that have annual probabilities greater than 10{sup {minus}9}/yr. The largest offsite dose is calculated to be 220 mrem, which is less than the 500 mrem value used to define items important to safety in 10 CFR 60. The study does not address an estimate of uncertainties, therefore conclusions or decisions made as a result of this report should be made with caution.

  6. Khorasan wheat population researching (Triticum turgidum, ssp. Turanicum (McKey in the minimum tillage conditions

    Directory of Open Access Journals (Sweden)

    Ikanović Jela

    2014-01-01

    Full Text Available Khorasan wheat occupies a special place in the group of new-old cereals (Triticum turgidum, ssp. Turanicum McKey. It is an ancient species, native to eastern Persia, that is very close to durum wheat by morphological characteristics. Investigations were carried out in agro ecological conditions of the eastern Srem, with two wheat populations with dark and bright awns as objects of study. The following morphological and productive characteristics were investigated: plant height (PH, spike length (SH, number of spikelets per spike (NSS, absolute weight (AW and grain weight per spike (GW, seed germination (G and grains yield (YG. Field micro-experiments were set on the carbonate chernozem soil type on loess plateau in 2011 and 2012. Hand wheat sowing was conducted in early March with drill row spacing of 12 cm. The experiment was established as complete randomized block system with four replications. Tending crops measures were not applied during the growing season. Plants were grown without usage of NPK mineral nutrients. Chemical crop protection measures were not applied, although powdery mildew (Erysiphe graminis was appeared before plants spike formation in a small extent. The results showed that both populations have a genetic yield potential. In general, both populations manifested a satisfactory tolerance on lodging and there was no seed dispersal. Plants from bright awns population were higher, had longer spikes and larger number of spikelet’s per spike. However, plants from dark awns population had higher absolute weight and grains weight per spike, as well as grain yield per plant. Strong correlation connections were identified among the investigated characteristics. The determination of correlations, as well as direct and indirect affects, enabled easier understanding of the mutual relationships and their balancing in order to improve the yield per unit area. [Projekat Ministarstva nauke Republike Srbije, br. TR 31078 i br. TR 31022

  7. Accidents at work and living conditions among solid waste segregators in the open dump of Distrito Federal.

    Science.gov (United States)

    Hoefel, Maria da Graça; Carneiro, Fernando Ferreira; Santos, Leonor Maria Pacheco; Gubert, Muriel Bauerman; Amate, Elisa Maria; dos Santos, Wallace

    2013-09-01

    The work of recycling solid waste segregators allows a precarious livelihood, but triggers a disease process that exacerbates their health and well-being. This study aimed to estimate the prevalence of occupational accidents at the open dump in the Federal District and its associated factors. Most segregators have had an accident at work (55.5%), perceived the danger of their working environment (95.0%) and claimed they did not receive personal protective equipment (51.7%). Among other findings, 55.8% ate foods found in the trash, 50.0% experienced food insecurity at home and 44.8% received Bolsa Família. There was a statistically significant relationship between work accidents and perception of dangerous work environment, household food insecurity and the presence of fatigue, stress or sadness (p waste segregators constitute a vulnerable community, not only from the perspective of labor, but also from the social and environmental circumstances. To reverse this situation, effective implementation of the National Policy of Solid Wastes is imperative, in association with affirmative policies to grant economic emancipation for this population. PMID:24896289

  8. The long-term cooling of the RU VVER in the conditions of design beyond basis accident

    International Nuclear Information System (INIS)

    MCC rupture on outlet, inlet the reactor (with coolant double end leakage); MCC rupture in the bottom part of a loop seal (with coolant double end leakage); Rupture of the connecting pipeline of HA (JNG10-40) of the ECCS (D = 300 mm); Loss of an alternating current sources, failure of safety active systems for more than 24 hours, failure of all diesel-generators; emergency supply from accumulators; Water injection from a fuel storage pool begins after emptying of tanks GE-2 (JNG50-80) with the total mass flow rate of 3.2 kg/s. The RELAP5/ANGAR code was used. The sequence of events and the work of the systems at a guillotine rupture of the MCC is described. The computing analysis of the beyond design accident which includes MCC rupture with loss of all sources of an alternating current, including diesel engines-generators, demonstrated the following: (i) the intervention of the safety systems of the NVNPP-2 project meets all Russian and international requirements to localizing functions by NVNPP-2 containment at beyond design accidents with leaks from the reactor facility; (ii) water injection from ST after the termination of work; (iii) GE-2 provides reliable core cooling for the beyond design basis accident scenarios during 74-88 hours in dependence on the leak size and location. (P.A.)

  9. Accidents at work and living conditions among solid waste segregators in the open dump of Distrito Federal.

    Science.gov (United States)

    Hoefel, Maria da Graça; Carneiro, Fernando Ferreira; Santos, Leonor Maria Pacheco; Gubert, Muriel Bauerman; Amate, Elisa Maria; dos Santos, Wallace

    2013-09-01

    The work of recycling solid waste segregators allows a precarious livelihood, but triggers a disease process that exacerbates their health and well-being. This study aimed to estimate the prevalence of occupational accidents at the open dump in the Federal District and its associated factors. Most segregators have had an accident at work (55.5%), perceived the danger of their working environment (95.0%) and claimed they did not receive personal protective equipment (51.7%). Among other findings, 55.8% ate foods found in the trash, 50.0% experienced food insecurity at home and 44.8% received Bolsa Família. There was a statistically significant relationship between work accidents and perception of dangerous work environment, household food insecurity and the presence of fatigue, stress or sadness (p solid waste segregators constitute a vulnerable community, not only from the perspective of labor, but also from the social and environmental circumstances. To reverse this situation, effective implementation of the National Policy of Solid Wastes is imperative, in association with affirmative policies to grant economic emancipation for this population.

  10. Monitoring transport conditions of key comparison travelling standards using a data logger. Experiences from key comparison CCAUV.U-K3.1

    Science.gov (United States)

    Haller, Julian; Koch, Christian

    2015-12-01

    In the framework of the international key comparison CCAUV.U-K3.1, a data logger was used to monitor temperature, pressure, humidity, and acceleration during transportation of an artefact travelling between participating laboratories. From the recorded data, environmental conditions of different kinds of transportation have been investigated and corresponding recommendations for the safe and proper transfer of artefacts between laboratories could be deduced. Transportation by courier services bears the risk of strong mechanical shocks and exposure to comparably high or low temperatures due to inappropriate handling or storage and is thus only suitable for insensitive or well-packed artefacts. Quite low temperatures (T  ≈  5 °C) have been observed in the cargo area during flights, so that hand-carrying of an artefact with transportation in the passenger cabin during flights is recommended, particularly for temperature-sensitive artefacts. Significant decreases of the pressure (p  ≈  750 mbar) have been recorded both for transportation in the passenger cabin and in the cargo area. Air-tight packing is thus recommended for pressure-sensitive devices. In general, the suitability of a data logger to provide evidence of the transport conditions during a key comparison has been demonstrated and the use of such a device is recommended for all key comparisons. The data logger has also been successfully employed to validate the protection properties of the passively insulating packaging of the artefact against pressure and temperature changes.

  11. Accidents - personal factors

    Energy Technology Data Exchange (ETDEWEB)

    Zaitsev, S.L.; Tsygankov, A.V.

    1982-03-01

    This paper evaluates influence of selected personal factors on accident rate in underground coal mines in the USSR. Investigations show that so-called organizational factors cause from 80 to 85% of all accidents. About 70% of the organizational factors is associated with social, personal and economic features of personnel. Selected results of the investigations carried out in Donbass mines are discussed. Causes of miner dissatisfaction are reviewed: 14% is caused by unsatisfactory working conditions, 21% by repeated machine failures, 16% by forced labor during days off, 14% by unsatisfactory material supply, 16% by hard physical labor, 19% by other reasons. About 25% of miners injured during work accidents are characterized as highly professionally qualified with automatic reactions, and about 41% by medium qualifications. About 60% of accidents is caused by miners with less than a 3 year period of service. About 15% of accidents occurs during the first month after a miner has returned from a leave. More than 30% of accidents occurs on the first work day after a day or days off. Distribution of accidents is also presented: 19% of accidents occurs during the first 2 hours of a shift, 36% from the second to the fourth hour, and 45% occurs after the fourth hour and before the shift ends.

  12. 核舰船核事故应急救援行动要点研究%Study on Key Points of Nuclear Accident Emergency Rescue Operation for Nuclear Powered Vessel

    Institute of Scientific and Technical Information of China (English)

    许明剑; 余刃; 寿宇强; 杨倩

    2015-01-01

    核动力舰船是移动的核设施,诱发核事故因素多,核应急救援组织指挥难度大。针对核动力舰船核事故特点,提出了迅速展开响应、严密组织指挥、注重技术救援、加强全局统筹等四个方面的行动要点,为组织开展核动力舰船核事故应急救援行动提供了参考。%Nuclear-powered vessels are mobile nuclear facilities. Multiple factors which may induce nuclear accident bring great difficulties to the organization and command of the nuclear emergency rescue. Based on the analysis of the characteristics of nuclear accidents on nuclear-powered vessels, the authors propose four key points of the rescue operation, i.e., rapid response, well-organized command, technical rescue and overall planning, which provide reference for the organization and implementation of the nuclear accident emergency rescue operation.

  13. Management of severe accidents

    International Nuclear Information System (INIS)

    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)

  14. Radio-contaminant behaviour in the cover-gas space and the containment building of a sodium-cooled fast reactor in accident conditions

    International Nuclear Information System (INIS)

    experiments chosen in the literature. The mass of oxide aerosols produced by a sodium spray fire can involve more than 60% of the ejected sodium. Then, we develop the numerical simulation STARK based on the Cooper model that model the physico-chemical transformations of the aerosols. However, this model has never been validated and the literature does not permit to do so. In these conditions, we designed and performed our own experiment to obtain the missing values of parameters that govern the Cooper model. The Cooper model has been improved with the results of this experimental study, ESSTIA, and we present a modified Cooper model that improves the accuracy of Cooper model to investigate the transformation of the sodium aerosols. The last part of the manuscript deals with the interaction between sodium aerosols (hydroxide) and a key fission product (iodine). We use density functional theory numerical simulation (the VASP code) to discover the affinities that can be identified. The results will facilitate simulation of the source term evolution because the sodium aerosols will interact with this FP. All the data and numerical simulations presented here will contribute to implementation of models in the future SFR SA numerical simulation of the IRSN, ASTEC-Na. (author)

  15. 49 CFR 195.54 - Accident reports.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Accident reports. 195.54 Section 195.54... PIPELINE Annual, Accident, and Safety-Related Condition Reporting § 195.54 Accident reports. (a) Each operator that experiences an accident that is required to be reported under § 195.50 shall as soon...

  16. Nuclear accidents

    International Nuclear Information System (INIS)

    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

  17. Bicycle accidents.

    Science.gov (United States)

    Lind, M G; Wollin, S

    1986-01-01

    Information concerning 520 bicycle accidents and their victims was obtained from medical records and the victims' replies to questionnaires. The analyzed aspects included risk of injury, completeness of accident registrations by police and in hospitals, types of injuries and influence of the cyclists' age and sex, alcohol, fatigue, hunger, haste, physical disability, purpose of cycling, wearing of protective helmet and other clothing, type and quality of road surface, site of accident (road junctions, separate cycle paths, etc.) and turning manoeuvres.

  18. An analysis of impact on the environmental pollution under accident conditions due to the disposal of ashes from the Nikola Tesla B thermal power plant

    International Nuclear Information System (INIS)

    The ash disposal area of Nikola Tesla B TPP is presenting considerable potential source of environmental pollution. Due to its vast area, that is for an effective plot of about 400 ha, under unfavorable meteorological conditions the emerging of ash cloud spreading over the surrounding area at distances of over 15 km could be produced. This paper deals with accident conditions at ash disposal area which, after stopping of sprinkling operation or in case of an inadequate sequence of ash tapping, when larger portions of disposal area are dried, turn into area of air polluting sources. Computations of particle dispersions under such conditions have been performed for different meteorological conditions and the results are represented as space distribution of particle deposition on the soil and their concentration in the air. (author). 5 figs., 4 refs

  19. Influence of aging on the retention of elemental radioiodine by deep bed carbon filters under accident conditions

    International Nuclear Information System (INIS)

    No significant difference was found in the retention of I-131 loaded as I2, by various impregnated activated carbons that had been aged in the containment exhaust air of a pressurized water reactor over a period of 12 months. In all the cases, the I-131 passing through deep beds of carbon was in a nonelemental form. It was concluded that a minimum retention of 99.99%, as required by new guidelines for certain accident filters, can be equally well achieved with various carbons in deep beds

  20. Report 1. An experiment model. Radiation loading in animals living in conditions of external and internal irradiation within the zone of Chernobyl accident

    International Nuclear Information System (INIS)

    Irradiation conditions in which laboratory animals were kept in experimental laboratories of Chernobyl and Kiev after the accident APS are described. The data are presented on the spectral structure and activity of radionuclides in the diet as well as in the organs and tissues of the animals. The radition loads have been estimated with regard to an external gamma-component and the internal one contributed by the incorporated radionuclides. It has been shown that radiation doses received by the animals during their lifetime due to these contributions do not exceed units of cGy

  1. The influence of the environmental and psychological factors of the Chernobyl' accident on the functional condition of regulatory hormone system in man

    International Nuclear Information System (INIS)

    The functional condition of the studied hormone systems (hormones in the periphery blood) in young men taken part in the accident liquidation and suffered from neuro-circulatory dystonia has been shown to have a number of peculiarities. In the bar period after leaving the 30-km zone the excess of adrenal cortex activity on the background of the impairment of the mechanism of the negative feedback in the hypothis-adrenal system has been registered. This fact is reflected in the state of the hormonal functions regulating the vessel tonus and hydrocarbon exchange resulting in the dystonia reaction of the hypertonia type. 12 refs.; 1 tab

  2. Key issues on safety design basis selection and safety assessment

    International Nuclear Information System (INIS)

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

  3. An Innovative Continuing Nursing Education Program Targeting Key Geriatric Conditions for Hospitalized Older People in China

    Science.gov (United States)

    Xiao, Lily Dongxia; Shen, Jun; Wu, Haifeng; Ding, Fu; He, Xizhen; Zhu, Yueping

    2013-01-01

    A lack of knowledge in registered nurses about geriatric conditions is one of the major factors that contribute to these conditions being overlooked in hospitalized older people. In China, an innovative geriatric continuing nursing education program aimed at developing registered nurses' understanding of the complex care needs of hospitalized…

  4. A Comprehensive Test of General Strain Theory: Key Strains, Situational- and Trait-Based Negative Emotions, Conditioning Factors, and Delinquency

    Science.gov (United States)

    Moon, Byongook; Morash, Merry; McCluskey, Cynthia Perez; Hwang, Hye-Won

    2009-01-01

    Using longitudinal data on South Korean youth, the authors addressed limitations of previous tests of general strain theory (GST), focusing on the relationships among key strains, situational- and trait-based negative emotions, conditioning factors, and delinquency. Eight types of strain previously shown most likely to result in delinquency,…

  5. Modelling the chemical behaviour of tellurium species in the reactor pressure vessel and the reactor cooling system under severe accident conditions

    International Nuclear Information System (INIS)

    This state of the art report contains information on the behaviour of tellurium and its compounds in the reactor pressure vessel and the reactor coolant system under light water reactor severe accident conditions. To characterise tellurium behaviour, it is necessary the previous knowledge of the species of tellurium released from the core, and simultaneity of its release with that of other materials which can alter the transport, for instance, control rod and structural materials. Release and transport experiments have been reviewed along with the models implemented in the codes which are used in the international community: TRAPMELT, RAFT, VICTORIA and SOPHIE. From the experiments, it can be concluded that other species different to Te2, such as tin telluride and cesium telluride, may be released from the fuel. That is why they must be considered in the transport phenomena. There is also experimental evidence of the strong interaction of Te2 with Inconel 600 and stainless steel of the pipe walls and structures, however this strong interaction is in competition with the interaction of tellurium with aerosols, which under severe accident conditions may represent an area greater than that of the primary system. It is for the absence of significant tellurium species in the transport models, and also for the interaction of tellurium with aerosols, for which some codes show the greatest deficiencies

  6. ROAD ACCIDENT AND SAFETY STUDY IN SYLHET REGION OF BANGLADESH

    Directory of Open Access Journals (Sweden)

    B. K. BANIK

    2011-08-01

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

  7. Research on Key Techniques of Condition Monitoring and Fault Diagnosing Systems of Machine Groups

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-kai; LIAO Ming-fu; WANG Si-ji

    2005-01-01

    This paper describes the development of the condition monitoring and fault diagnosing system of a group of rotating machinery. The data management is performed by means of double redundant data bases stored simultaneously in both the analyzing server and monitoring client. In this way, high reliability of the storage of data is guaranteed. Condensation of trend data releases much space resource of the hard disk. Diagnosing strategies orientated to different typical faults of rotating machinery are developed and incorporated into the system. Experimental verification shows that the system is suitable and effective for condition monitoring and fault diagnosing for a rotating machine group.

  8. Modelling of Zry-4 cladding oxidation by air, under severe accident conditions using the MAAP4 code

    Energy Technology Data Exchange (ETDEWEB)

    Beuzet, Emilie, E-mail: emilie.beuzet@edf.f [EDF R and D, 1 Avenue du General de Gaulle, F-92140 Clamart (France); Lamy, Jean-Sylvestre, E-mail: jean-sylvestre.lamy@edf.f [EDF R and D, 1 Avenue du General de Gaulle, F-92140 Clamart (France); Bretault, Armelle, E-mail: armelle.bretault@edf.f [EDF R and D, 1 Avenue du General de Gaulle, F-92140 Clamart (France); Simoni, Eric, E-mail: simoni@ipno.in2p3.f [Institut de Physique Nucleaire, Universite Paris Sud XI, F-91406 Orsay (France)

    2011-04-15

    In a nuclear power plant, a potential risk in some low probability situations in severe accidents is air ingress into the vessel. Air is a highly oxidizing atmosphere that can lead to an enhanced core oxidation and degradation affecting the release of Fission Products (FP), especially increasing that of ruthenium. This FP is of particular importance because of its high radio-toxicity and its ability to form highly volatile oxides. Oxygen affinity is decreasing between Zircaloy cladding, fuel and ruthenium inclusions in the fuel. It is consequently of great need to understand the phenomena governing cladding oxidation by air as a prerequisite for the source term issues. A review of existing data in the field of Zircaloy-4 oxidation in air-containing atmosphere shows that this phenomenon is quantitatively well understood. The cladding oxidation process can be divided into two kinetic regimes separated by a breakaway transition. Before transition, a protective dense zirconia scale grows following a solid state diffusion-limited regime for which experimental data are well fitted by a parabolic time dependence. For a given thickness, which depends mainly on temperature and the extent of pre-oxidation in steam, the dense scale can potentially breakdown. In case of breakaway combined with oxygen starvation, cladding oxidation can then be much faster because of the combined action of oxygen and nitrogen through a complex self sustaining nitriding-oxidation process. A review of the pre-existing correlations used to simulate zirconia scale growth under air atmospheres shows a high degree of variation from parabolic to accelerated time dependence. Variations also exist in the choice of the breakaway parameter based on zirconia phase change or oxide thickness. Several correlations and breakaway parameters found in the literature were implemented in the MAAP4.07 Severe Accident code. They were assessed by simulation of the QUENCH-10 test, which is a semi-integral test designed

  9. Modelling of Zry-4 cladding oxidation by air, under severe accident conditions using the MAAP4 code

    International Nuclear Information System (INIS)

    In a nuclear power plant, a potential risk in some low probability situations in severe accidents is air ingress into the vessel. Air is a highly oxidizing atmosphere that can lead to an enhanced core oxidation and degradation affecting the release of Fission Products (FP), especially increasing that of ruthenium. This FP is of particular importance because of its high radio-toxicity and its ability to form highly volatile oxides. Oxygen affinity is decreasing between Zircaloy cladding, fuel and ruthenium inclusions in the fuel. It is consequently of great need to understand the phenomena governing cladding oxidation by air as a prerequisite for the source term issues. A review of existing data in the field of Zircaloy-4 oxidation in air-containing atmosphere shows that this phenomenon is quantitatively well understood. The cladding oxidation process can be divided into two kinetic regimes separated by a breakaway transition. Before transition, a protective dense zirconia scale grows following a solid state diffusion-limited regime for which experimental data are well fitted by a parabolic time dependence. For a given thickness, which depends mainly on temperature and the extent of pre-oxidation in steam, the dense scale can potentially breakdown. In case of breakaway combined with oxygen starvation, cladding oxidation can then be much faster because of the combined action of oxygen and nitrogen through a complex self sustaining nitriding-oxidation process. A review of the pre-existing correlations used to simulate zirconia scale growth under air atmospheres shows a high degree of variation from parabolic to accelerated time dependence. Variations also exist in the choice of the breakaway parameter based on zirconia phase change or oxide thickness. Several correlations and breakaway parameters found in the literature were implemented in the MAAP4.07 Severe Accident code. They were assessed by simulation of the QUENCH-10 test, which is a semi-integral test designed

  10. Accident Statistics

    Data.gov (United States)

    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...

  11. Stakeholder involvement in the rehabilitation of living conditions in contaminated territories affected by the Chernobyl accident. The ETHOS Project in Belarus

    International Nuclear Information System (INIS)

    The management of the Chernobyl post-accident situation is a complex process comprising not only radiological protection but also psychological, social, economic, political and ethical dimensions. Involving in this process local communities who are directly concerned by the consequences of the accident is a strong lever in improving their living conditions as well as restoring their confidence in experts and the authorities. This paper presents the experience of the involvement of a group of mothers from a village in the Republic of Belarus in activities to improve the radiological protection of their children. This experience took place in the framework of the ETHOS Project supported by the radiation protection research programme of the European Commission with the objective of implementing an alternative approach to the rehabilitation strategies adopted so far in the contaminated territories of the CIS. The first part of the paper presents briefly the main features of the methodological and practical approach of the ETHOS Project. The second part describes in more detail how the mothers voluntarily got involved in a working group set up within the framework of the Project, the characterization of the radiological situation they carried out, the concrete approach they developed to regain control of the situation, the way the health care system has been involved in the process and finally, the results they achieved in reducing the internal contamination of their children. (author)

  12. Sports Accidents

    CERN Multimedia

    Kiebel

    1972-01-01

    Le Docteur Kiebel, chirurgien à Genève, est aussi un grand ami de sport et de temps en temps médecin des classes genevoises de ski et également médecin de l'équipe de hockey sur glace de Genève Servette. Il est bien qualifié pour nous parler d'accidents de sport et surtout d'accidents de ski.

  13. Mycobacterium tuberculosis Adaptation to Gradually Oxygen Depletion Condition Is a Key Factor for Latency of Tuberculosis

    Directory of Open Access Journals (Sweden)

    M NajafiMosleh

    2007-06-01

    Full Text Available Background: There is ample evidence that the basis for latent tuberculosis infection in humans is persistence of tubercle bacilli for long periods of time even though lifetime. This status is currently defined as non-replicating persistence (NRP. Documented evidence from both macrophage physiology & the nature of TB granuloumas in human lungs suggests that gradually depletion of oxygen, hypoxia and micro aerobic condition is a major factor in inducing NRP state of tubercle bacilli. Methods: 100 clinically isolated tubercle bacilli were examined by the slowly stirred head space ratio method (0.5 HSR, which involve a slow depletion of oxygen within a sealed, slow stirred culture tube. The in-vitro induced hypoxically different stages of NRP was setting up, and the expression of the alpha-crystalline chaperone protein that are expressed when MTB undergoes to NRP srate was detected. Indeed the activity of rifampin, isoniazide, pyrazynamide, ciprofloxacin and meteronidazole were evaluated against two NRP stages of MTB. Results: During oxygen shift-down bacterial physiology changes from active growth to a NRP state. Two characteristic stages of NRP are seen; NRP-1 occurs when the oxygen concentration gradually dropped to microaerophilic condition. The 16 KD α- crystalline protein was expressed at just beginning of NRP-1 stage. The NRP-2 stages occur when the oxygen concentration dropped to anaerobic condition. When the NRP-2 state transferred to an oxygen – reach fresh medium the bacteria consume oxygen and resume growth in a synchronized replication manner from NRP-2 state. Conclusion: slow depletion of O2 appears to permit the occurrence of adaptations that favor long-term non replicating persistence of tubercle bacilli under microaerophilic conditions and also enhance the ability of the bacilli to survive in anaerobic conditions. This versatility could account for long-term latency of tuberculosis in the human host. The model presented here

  14. Accident management information needs

    International Nuclear Information System (INIS)

    In support of the US Nuclear Regulatory Commission (NRC) Accident Management Research Program, a methodology has been developed for identifying the plant information needs necessary for personnel involved in the management of an accident to diagnose that an accident is in progress, select and implement strategies to prevent or mitigate the accident, and monitor the effectiveness of these strategies. This report describes the methodology and presents an application of this methodology to a Pressurized Water Reactor (PWR) with a large dry containment. A risk-important severe accident sequence for a PWR is used to examine the capability of the existing measurements to supply the necessary information. The method includes an assessment of the effects of the sequence on the measurement availability including the effects of environmental conditions. The information needs and capabilities identified using this approach are also intended to form the basis for more comprehensive information needs assessment performed during the analyses and development of specific strategies for use in accident management prevention and mitigation. 3 refs., 16 figs., 7 tabs

  15. Nitrogen assimilation and transpiration: key processes conditioning responsiveness of wheat to elevated [CO2] and temperature.

    Science.gov (United States)

    Jauregui, Iván; Aroca, Ricardo; Garnica, María; Zamarreño, Ángel M; García-Mina, José M; Serret, Maria D; Parry, Martin; Irigoyen, Juan J; Aranjuelo, Iker

    2015-11-01

    Although climate scenarios have predicted an increase in [CO(2)] and temperature conditions, to date few experiments have focused on the interaction of [CO(2)] and temperature effects in wheat development. Recent evidence suggests that photosynthetic acclimation is linked to the photorespiration and N assimilation inhibition of plants exposed to elevated CO(2). The main goal of this study was to analyze the effect of interacting [CO(2)] and temperature on leaf photorespiration, C/N metabolism and N transport in wheat plants exposed to elevated [CO(2)] and temperature conditions. For this purpose, wheat plants were exposed to elevated [CO(2)] (400 vs 700 µmol mol(-1)) and temperature (ambient vs ambient + 4°C) in CO(2) gradient greenhouses during the entire life cycle. Although at the agronomic level, elevated temperature had no effect on plant biomass, physiological analyses revealed that combined elevated [CO(2)] and temperature negatively affected photosynthetic performance. The limited energy levels resulting from the reduced respiratory and photorespiration rates of such plants were apparently inadequate to sustain nitrate reductase activity. Inhibited N assimilation was associated with a strong reduction in amino acid content, conditioned leaf soluble protein content and constrained leaf N status. Therefore, the plant response to elevated [CO(2)] and elevated temperature resulted in photosynthetic acclimation. The reduction in transpiration rates induced limitations in nutrient transport in leaves of plants exposed to elevated [CO(2)] and temperature, led to mineral depletion and therefore contributed to the inhibition of photosynthetic activity. PMID:25958969

  16. Full-scale modelling of the MNSR reactor to simulate normal operation, transients and reactivity insertion accidents under natural circulation conditions using the thermal hydraulic code ATHLET

    International Nuclear Information System (INIS)

    A full-scale ATHLET system model for the Syrian miniature neutron source reactor (MNSR) has been developed. The model represents all reactor components of primary and secondary loops with the corresponding neutronics and thermal hydraulic characteristics. Under the MNSR operation conditions of natural circulation, normal operation, step reactivity transients and reactivity insertion accidents have been simulated. The analyses indicate the capability of ATHLET to simulate MNSR dynamic and thermal hydraulic behaviour and particularly to calculate the core coolant velocity of prevailing natural circulation in presence of the strong negative reactivity feed back of coolant temperature. The predicted time distribution of reactor power, core inlet and outlet coolant temperature follow closely the measured data for the quasi steady and transient states. However, sensitivity analyses indicate the influence of pressure form loss coefficients at core inlet and outlet on the results. The analysis of reactivity accidents represented by the insertion of large reactivity, demonstrates the high inherent safety features of MNSR. Even in case of insertion of total available cold excess reactivity without scram, the high negative reactivity feedback of moderator temperature limits power excursion and avoids consequently the escalation of clad temperature to the level of onset of sub-cooled void formation. The calculated peak power in this case agrees well with the data reported in the safety analysis report. The ATHLET code had not previously been assessed under these conditions. The results of this comprehensive analysis ensure the ability of the code to test some conceptual design modifications of MNSR's cooling system aiming the improvement of core cooling conditions to increase the maximum continuous reactor operation time allowing more effective use of MNSR for irradiation purposes

  17. Full-scale modelling of the MNSR reactor to simulate normal operation, transients and reactivity insertion accidents under natural circulation conditions using the thermal hydraulic code ATHLET

    Energy Technology Data Exchange (ETDEWEB)

    Hainoun, A. [Department of Nuclear Engineering, Atomic Energy Commission, P.O. Box 6091, Damascus (Syrian Arab Republic)]. E-mail: ahainoun@aec.org.sy; Alissa, S. [Department of Nuclear Engineering, Atomic Energy Commission, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2005-01-01

    A full-scale ATHLET system model for the Syrian miniature neutron source reactor (MNSR) has been developed. The model represents all reactor components of primary and secondary loops with the corresponding neutronics and thermal hydraulic characteristics. Under the MNSR operation conditions of natural circulation, normal operation, step reactivity transients and reactivity insertion accidents have been simulated. The analyses indicate the capability of ATHLET to simulate MNSR dynamic and thermal hydraulic behaviour and particularly to calculate the core coolant velocity of prevailing natural circulation in presence of the strong negative reactivity feed back of coolant temperature. The predicted time distribution of reactor power, core inlet and outlet coolant temperature follow closely the measured data for the quasi steady and transient states. However, sensitivity analyses indicate the influence of pressure form loss coefficients at core inlet and outlet on the results. The analysis of reactivity accidents represented by the insertion of large reactivity, demonstrates the high inherent safety features of MNSR. Even in case of insertion of total available cold excess reactivity without scram, the high negative reactivity feedback of moderator temperature limits power excursion and avoids consequently the escalation of clad temperature to the level of onset of sub-cooled void formation. The calculated peak power in this case agrees well with the data reported in the safety analysis report. The ATHLET code had not previously been assessed under these conditions. The results of this comprehensive analysis ensure the ability of the code to test some conceptual design modifications of MNSR's cooling system aiming the improvement of core cooling conditions to increase the maximum continuous reactor operation time allowing more effective use of MNSR for irradiation purposes.

  18. Reducing conditions are the key for efficient production of active ribonuclease inhibitor in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Neubauer Peter

    2011-05-01

    Full Text Available Abstract Background The eukaryotic RNase ribonuclease/angiogenin inhibitors (RI are a protein group distinguished by a unique structure - they are composed of hydrophobic leucine-rich repeat motifs (LRR and contain a high amount of reduced cysteine residues. The members of this group are difficult to produce in E. coli and other recombinant hosts due to their high aggregation tendency. Results In this work dithiothreitol (DTT was successfully applied for improving the yield of correctly folded ribonuclease/angiogenin inhibitor in E. coli K12 periplasmic and cytoplasmic compartments. The feasibility of the in vivo folding concepts for cytoplasmic and periplasmic production were demonstrated at batch and fed-batch cultivation modes in shake flasks and at the bioreactor scale. Firstly, the best secretion conditions of RI in the periplasmic space were evaluated by using a high throughput multifactorial screening approach of a vector library, directly with the Enbase fed-batch production mode in 96-well plates. Secondly, the effect of the redox environment was evaluated in isogenic dsbA+ and dsbA- strains at the various cultivation conditions with reducing agents in the cultivation medium. Despite the fusion to the signal peptide, highest activities were found in the cytoplasmic fraction. Thus by removing the signal peptide the positive effect of the reducing agent DTT was clearly proven also for the cytoplasmic compartment. Finally, optimal periplasmic and cytoplasmic RI fed-batch production processes involving externally added DTT were developed in shake flasks and scaled up to the bioreactor scale. Conclusions DTT highly improved both, periplasmic and cytoplasmic accumulation and activity of RI at low synthesis rate, i.e. in constructs harbouring weak recombinant synthesis rate stipulating genetic elements together with cultivation at low temperature. In a stirred bioreactor environment RI folding was strongly improved by repeated pulse addition

  19. An international standard problem: analysis of 1:4-scale prestressed concrete containment vessel model under severe accident conditions

    International Nuclear Information System (INIS)

    In June 2002, The OECD-NEA Committee on the Safety of Nuclear Installations (CSNI), with the encouragement of the US NRC, initiated an International Standard Problem on containment integrity (ISP 48) based on the NRC/NUPEC/Sandia test. The objectives of the ISP are to extend the understanding of capacities of actual containment structures based on results of the recent PCCV Model test and other previous research. From 1997 through 2001 Sandia National Laboratories (SNL) conducted a Cooperative Containment Integrity Program under the joint sponsorship of the Nuclear Power Engineering Corporation (NUPEC) of Japan, and the NRC Office of Nuclear Regulatory Research. The purpose of the program was to investigate the response of representative models of nuclear containment structures to pressure loading beyond the design basis accident and to compare analytical predictions to measured behavior. A uniform 1:4-scale model of a prestressed concrete containment vessel (PCCV) was constructed and tested at SNL. This model was representative of the containment structure of an actual pressurized-water reactor plant in Japan. The ISP consists of four phases over a period of 2 years: Phase 1: Data Collection and Identification Phase 2: Calculation of the Limit State Test (LST), i.e. static pressure loading Phase 3: Calculation of response to both Thermal and Mechanical Loadings Phase 4: Reporting Workshop Eleven organizations (or teams) from nine OECD member countries accepted the invitation to participate in the ISP and perform calculations to predict the structural response of the PCCV model to static and transient pressure and thermal loading. Each participating organization was provided with the model and loading data and was asked to perform independent analyses to simulate the response of the PCCV model. The results of each team's calculations were compiled and the results presented at a final workshop in April 2005. These results and the conclusions and insights gained from

  20. The Key Role of Government in Addressing the Pandemic of Micronutrient Deficiency Conditions in Southeast Asia

    Directory of Open Access Journals (Sweden)

    Theodore H. Tulchinsky

    2015-04-01

    Full Text Available Micronutrient deficiency conditions are a major global public health problem. While the private sector has an important role in addressing this problem, the main responsibility lies with national governments, in cooperation with international agencies and donors. Mandatory fortification of basic foods provides a basic necessary intake for the majority and needs to be supported by provision of essential vitamin and mineral supplements for mothers and children and other high risk groups. Fortification by government mandate and regulation is essential with cooperation by private sector food manufacturers, and in the context of broader policies for poverty reduction, education and agricultural reform. Iron, iodine, vitamin A, vitamin B complex, folic acid, zinc, vitamin D and vitamin B12 are prime examples of international fortification experience achieved by proactive governmental nutrition policies. These are essential to achieve the Millennium Development Goals and their follow-up sustainable global health targets. National governmental policies for nutritional security and initiatives are essential to implement both food fortification and targeted supplementation policies to reduce the huge burden of micronutrient deficiency conditions in Southeast Asia and other parts of the world.

  1. Licensing topical report: the measurement and modelling of time-dependent fission product release from failed HTGR fuel particles under accident conditions

    International Nuclear Information System (INIS)

    The release of fission products from failed fuel particles was measured under simulated accident (core heatup) conditions. A generic model and specific model parameters that describe delayed fission product release from the kernels of failed HTGR fuel particles were developed from the experimental results. The release of fission products was measured from laser-failed BISO ThO2 and highly enriched (HEU) TRISO UC2 particles that had been irradiated to a range of kernel burnups. The burnups were 0.25, 1.4, and 15.7% FIMA for ThO2 particles and 23.5 and 74% FIMA for UC2 particles. The fission products measured were nuclides of xenon, iodine, krypton, tellurium, and cesium

  2. [Psychogenesis of accidents].

    Science.gov (United States)

    Giannattasio, E; Nencini, R; Nicolosi, N

    1988-01-01

    After having carried out a historical review of industrial psychology with specific attention to the evolution of the concept of causality in accidents, the Authors formulate their work hypothesis from that research which take into highest consideration the executives' attitudes in the genesis of the accidents. As dogmatism appears to be one of the most negative of executives' attitudes, the Authors administered Rockeach's Scale to 130 intermediate executives from 6 industries in Latium and observed the frequency index for accidents and the morbidity index (absenteeism) of the 2149 workhand. The Authors assumed that to high degree of dogmatism on the executives' side should correspond o a higher level of accidents and absenteeism among the staff. The data processing revealed that, due to the type of machinery employed, three of the industries examined should be considered as High Risk Industrie (HRI), while the remaining three could be considered as Low Risk Industries (LRI): in fact, due to the different working conditions, a significant lower number of accidents occurred in last the three. A statistically significant correlation between the executives' dogmatism and the number of accidents among their workhand in the HRI has been noticed, while this has not been observed in the LRI. This confirms, as had already been pointed out by Gemelli in 1944, that some "objective conditions" are requested so that the accident may actually take place. On the other hand the morbidity index has not shown any difference related to the different kind of industries (HRI, LRI): in both cases statistically significant correlations were obtained between the executives' dogmatism and the staff's absenteeism. absenteeism.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3154344

  3. A key role of transversality condition in quantization of photon orbital angular momentum

    CERN Document Server

    Li, Chun-Fang

    2016-01-01

    The effect of the constraint of transversality condition on the quantization of the photon orbital angular momentum is studied. From the point of view of quantum mechanics, the constraint expresses an entanglement between the intrinsic canonical variable, the polarization, and the extrinsic canonical variables. More importantly, its invariance under the rotation transformation of the vector wavefunction about the momentum turns out to mean the existence of degree of freedom of the Berry gauge, which appears as a constant unit vector. Because in each Berry-gauge representation, a two-component representation, the polarization is represented independently of the extrinsic canonical variables, the Berry-gauge degree of freedom has observable quantum effects. When the Berry-gauge degree of freedom of a paraxial beam is perpendicular to the propagation direction, the orbital angular momentum about the origin of the laboratory reference system reduces to its canonical part. Since the constraint together with the Sc...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-03-01

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

  5. Estimation of thermal loads on the VVER vessel under conditions of inversion of the stratified molten pool in a severe accident

    Science.gov (United States)

    Loktionov, V. D.; Mukhtarov, E. S.

    2016-09-01

    Analysis of the thermal state of molten pools that can be formed on the vessel bottom of the VVER-600 medium-power reactor during a severe anticipated accident with melting of the core is represented. Two types of the molten pool of core materials, with the two-layer and inverse three-layer stratification, are considered. Thermal loads acting on the reactor vessel from the melt are estimated depending on its formation time. Features of the thermal state of the melt in the case of its inverse stratification are analyzed. It is shown that thermal loads on the reactor vessel exceed the critical heat flux (CHF) when forming the two-layer stratified molten pool 10 and 24 h after its shutdown, and the thermal load is close to the corresponding CHF or somewhat exceeds it in 72 h. In the case of the formation of the inverse structure of the melt, one can observe a decrease by more than 2.5 times (in comparison with the two-layer stratified structure) in the thermal load on the reactor vessel in the region of its contact with the upper layer of the steel melt. Analysis of results showed that maximum densities of heat flux to the reactor vessel from the bottom metallic layer with the melt inversion did not exceed corresponding CHFs 24 and 72 h after the reactor shutdown. Because the thermal load on the reactor vessel can be localized in the region of its bottom, where the CHF is relatively small, during the inverse stratification of the melt, there is a need to carry out further in-depth experimental and analytical investigations of conditions for formation of the stratified molten pool and to obtain corrected experimental CHFs for conditions and outlines of cooling the external surface of the VVER-600 vessel in a severe accident.

  6. Plant cell death and cellular alterations induced by ozone: Key studies in Mediterranean conditions

    Energy Technology Data Exchange (ETDEWEB)

    Faoro, Franco, E-mail: franco.faoro@unimi.i [Istituto di Patologia Vegetale, Universita di Milano and CNR, Istituto di Virologia Vegetale, U.O.T di Milano, Via Celoria 2, 20133 Milan (Italy); Iriti, Marcello [Istituto di Patologia Vegetale, Universita di Milano and CNR, Istituto di Virologia Vegetale, U.O.T di Milano, Via Celoria 2, 20133 Milan (Italy)

    2009-05-15

    An account of histo-cytological and ultrastructural studies on ozone effect on crop and forest species in Italy is given, with emphasis on induced cell death and the underlying mechanisms. Cell death phenomena possibly due to ambient O{sub 3} were recorded in crop and forest species. In contrast, visible O{sub 3} effects on Mediterranean vegetation are often unclear. Microscopy is thus suggested as an effective tool to validate and evaluate O{sub 3} injury to Mediterranean vegetation. A DAB-Evans blue staining was proposed to validate O{sub 3} symptoms at the microscopic level and for a pre-visual diagnosis of O{sub 3} injury. The method has been positively tested in some of the most important crop species, such as wheat, tomato, bean and onion and, with some restriction, in forest species, and it also allows one to gain some very useful insights into the mechanisms at the base of O{sub 3} sensitivity or tolerance. - Ozone-induced cell death is a frequent phenomenon in Mediterranean conditions, not only in the most sensitive crops but also in forest species.

  7. Bacterial assisted degradation of chlorpyrifos: The key role of environmental conditions, trace metals and organic solvents.

    Science.gov (United States)

    Khalid, Saira; Hashmi, Imran; Khan, Sher Jamal

    2016-03-01

    Wastewater from pesticide industries, agricultural or surface runoff containing pesticides and their residues has adverse environmental impacts. Present study demonstrates effect of petrochemicals and trace metals on chlorpyrifos (CP) biotransformation often released in wastewater of agrochemical industry. Biodegradation was investigated using bacterial strain Pseudomonas kilonensis SRK1 isolated from wastewater spiked with CP. Optimal environmental conditions for CP removal were CFU (306 × 10(6)), pH (8); initial CP concentration (150 mg/L) and glucose as additional carbon source. Among various organic solvents (petrochemicals) used in this study toluene has stimulatory effect on CP degradation process using SRK1, contrary to this benzene and phenol negatively inhibited degradation process. Application of metal ions (Cu (II), Fe (II) Zn (II) at low concentration (1 mg/L) took part in biochemical reaction and positively stimulated CP degradation process. Metal ions at high concentrations have inhibitory effect on degradation process. A first order growth model was shown to fit the data. It could be concluded that both type and concentration of metal ions and petrochemicals can affect CP degradation process. PMID:26692411

  8. Bacterial assisted degradation of chlorpyrifos: The key role of environmental conditions, trace metals and organic solvents.

    Science.gov (United States)

    Khalid, Saira; Hashmi, Imran; Khan, Sher Jamal

    2016-03-01

    Wastewater from pesticide industries, agricultural or surface runoff containing pesticides and their residues has adverse environmental impacts. Present study demonstrates effect of petrochemicals and trace metals on chlorpyrifos (CP) biotransformation often released in wastewater of agrochemical industry. Biodegradation was investigated using bacterial strain Pseudomonas kilonensis SRK1 isolated from wastewater spiked with CP. Optimal environmental conditions for CP removal were CFU (306 × 10(6)), pH (8); initial CP concentration (150 mg/L) and glucose as additional carbon source. Among various organic solvents (petrochemicals) used in this study toluene has stimulatory effect on CP degradation process using SRK1, contrary to this benzene and phenol negatively inhibited degradation process. Application of metal ions (Cu (II), Fe (II) Zn (II) at low concentration (1 mg/L) took part in biochemical reaction and positively stimulated CP degradation process. Metal ions at high concentrations have inhibitory effect on degradation process. A first order growth model was shown to fit the data. It could be concluded that both type and concentration of metal ions and petrochemicals can affect CP degradation process.

  9. A preliminary study for the implementation of general accident management strategies

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Soo Hyung; Kim, Soo Hyung; Jeong, Young Hoon; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    To enhance the safety of nuclear power plants, implementation of accident management has been suggested as one of most important programs. Specially, accident management strategies are suggested as one of key elements considered in development of the accident management program. In this study, generally applicable accident management strategies to domestic nuclear power plants are identified through reviewing several accident management programs for the other countries and considering domestic conditions. Identified strategies are as follows; 1) Injection into the Reactor Coolant System, 2) Depressurize the Reactor Coolant System, 3) Depressurize the Steam Generator, 4) Injection into the Steam Generator, 5) Injection into the Containment, 6) Spray into the Containment, 7) Control Hydrogen in the Containment. In addition, the systems and instrumentation necessary for the implementation of each strategy are also investigated. 11 refs., 3 figs., 3 tabs. (Author)

  10. SUBSTANTIATION OF THE CONCEPT OF TRANSFER TO CONDITIONS OF NORMAL POPULATION ACTIVITY OF THE SETTLEMENTS CONSIDERED TO BE ZONES OF RADIOACTIVE CONTAMINATION AFTER THE CHERNOBYL NPP ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. K. Romanovich

    2016-01-01

    Full Text Available The article contains substantiation of criteria of return of territories with radioactive pollution caused by Chernobyl NPP accident to conditions of normal population activity. It is established that in 12 entities of the Russian Federation (except Bryansk and Kaluga regions all agricultural food produce, including that from the personal part-time farms, corresponds to hygienic specifications. Non- corresponding to the standard SanPiN 2.3.2.1078-01 on 137Cs are part of the milk samples produced at personal part-time farms of the Bryansk region and most of natural foodstuff samples (berries, mushrooms, fish and wild animals meat in Bryansk and Kaluga regions. The content of 137Cs both in agricultural and in wild-growing foodstuff produced at radioactively contaminated territories depends not only on the density of radioactive pollution, but also on the types of soil. The average settlement annual effective dose of population irradiation (AAED90 in the 3700 among 4413 settlements as of 2014 was below 0.3 mSv/year. Only in 713 settlements of Bryansk, Kaluga, Oryol and Tula regions the AAED90 exceeds 0.3 mSv/year. In the Bryansk region, once subject to the greatest radioactive contamination, in 276 settlements AAED90 exceeds 1 mSv/year, and in 8 of them - 5 mSv/year.The legislation of the Russian Federation defines only criteria and requirements for consideration of the suffered territories as zones of radioactive contamination. Requirements on transfer of territories polluted by radiation accidents and their population to normal life activity conditions (regarding the radiological factor are not developed.Radiological criteria are suggested for transfer of the settlements considered to be the zone of radioactive pollution to conditions of normal life activity: average irradiation dose of critical population group: 1.0 mSv per year and lower (AAED crit; decrease of radionuclide soil contamination density to the level enabling to use the territory

  11. Modelling of behaviour of 37 fuel rod assembly with Zr1%Nb-alloy simulators cladding under loss-of-coolant accident conditions on PARAMETR-M facility

    International Nuclear Information System (INIS)

    The experiment described in this report involves the implementation of conditions complying with the second stage of LOCA accident, for representative group of WWER-1000 fuel rods with relative heat generation rate in the range of 1.2-1.4 from the average one: maximal cladding temperature up to 9000C. The testing of experimental fuel rod assembly consisting of 37 fuel elements with Zr1%Nb-alloyed claddings has been made for representative group of heat-stressed fuel rods of the WWER-1000 type reactor on the electro heated PARAMETR-M facility under LOCA simulating conditions. The cladding rupture of fuel rods took place at the heating-up stage within the stated temperature interval 800-9000C. There were identified the basic cladding deformation and rupture parameters: temperature, pressure, axial distribution of hoop strain, and azimuthal distributions of radial deformation in rupture section. The experimental and calculated value of cross section blockage in the assembly under testing was 38%. The calculated values of cladding deformation and rupture parameters determined using RAPTA-5 Code agree well with experimental ones

  12. 基于事故/事件的民机人因防错设计关键因素研究%Research on key factors of human error proofing design for civil aircraft based on accidents/incidents

    Institute of Scientific and Technical Information of China (English)

    高扬; 王向章; 李晓旭

    2015-01-01

    Aiming at the influence of human error proofing design for civil aircraft on flight safety, 92 typical acci-dents cases by human factors were selected from the world civil aviation safety accidents/incidents database.The element incident analysis method was applied to conduct deep analysis, then the important design factors which need to be considered in the human error proofing design for civil aircraft was summarized, and the important design factor set was established.Based on the man-machine-environment model in systems engineering, and combined with the relevant standards for aircrafts design at home and abroad, an index system of important factors about hu-man error proofing design for civil aircraft was built.The FAHP method was used to calculate the weight of inde-xes, and 14 key factors of human error proofing design that influence the flight safety were determined.Finally, the general requirements of human error proofing design for civil aircraft were proposed against the key factors.It can provide reference for the human error proofing design for civil aircraft to better meet the requirements of initial air-worthiness.%针对民机人因防错设计对飞行安全的影响,从世界民航安全事故/事件数据库中筛选出92起典型的人为因素事故案例,采用基元事件分析法进行深度分析,提炼出民机人因防错设计需要考虑的重要设计因素,并建立重要设计因素集。基于系统工程学的“人机环”模型,结合国内外飞机设计相关标准,建立民机人因防错设计重要因素指标体系。运用模糊层次分析法对因素指标进行权重计算,确立影响飞行安全的14项人因防错设计关键因素,并针对这些关键因素提出民机人因防错设计通用要求,以期为民机人因防错设计满足初始适航要求提供参考。

  13. Computer system for the assessment of radiation situation in the cases of radiological accidents and extreme weather conditions in the Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    Radiation situation within the Chernobyl Exclusion Zone (ChEZ) is determined by high radionuclides contamination of the land surface formed after the 1986 accident, as well as the presence of a number of potentially hazardous objects (the 'Shelter' object, the Interim Spent Nuclear Fuel Dry Storage Facility ISF-1, radioactive waste disposal sites, radioactive waste temporary localization sites etc.). The air concentration of radionuclides over the ChEZ territory and radiation exposure of personnel are influenced by natural and anthropogenic factors: variable weather conditions, forest fires, construction and excavation activity etc. The comprehensive radiation monitoring and early warning system in the ChEZ was established under financial support of European Commission in 2011. It involves the computer system developed for assessment and prediction of radiological emergencies consequences in the ChEZ ensuring the protection of personnel and the population living near its borders. The system assesses radiation situation under both normal conditions in the ChEZ and radiological emergencies which result in considerable radionuclides emission into the air (accidents at radiation hazardous objects, extreme weather conditions). Three different types of radionuclides release sources can be considered in the software package. So it is based on a set of different models of emission, atmospheric transport and deposition of radionuclides: 1) mesoscale model of radionuclide atmospheric transport LEDI for calculations of the radionuclides emission from stacks and buildings; 2) model of atmospheric transport and deposition of radionuclides due to anthropogenic resuspension from contaminated area (area surface source model) as a result of construction and excavation activity, heavy traffic etc.; 3) model of resuspension, atmospheric transport and deposition of radionuclides during grassland and forest fires in the ChEZ. The system calculates the volume and surface specific

  14. Computer system for the assessment of radiation situation in the cases of radiological accidents and extreme weather conditions in the Chernobyl exclusion zone

    Energy Technology Data Exchange (ETDEWEB)

    Talerko, M.; Garger, E.; Kuzmenko, A. [Institute for Safety Problems of Nuclear Power Plants (Ukraine)

    2014-07-01

    Radiation situation within the Chernobyl Exclusion Zone (ChEZ) is determined by high radionuclides contamination of the land surface formed after the 1986 accident, as well as the presence of a number of potentially hazardous objects (the 'Shelter' object, the Interim Spent Nuclear Fuel Dry Storage Facility ISF-1, radioactive waste disposal sites, radioactive waste temporary localization sites etc.). The air concentration of radionuclides over the ChEZ territory and radiation exposure of personnel are influenced by natural and anthropogenic factors: variable weather conditions, forest fires, construction and excavation activity etc. The comprehensive radiation monitoring and early warning system in the ChEZ was established under financial support of European Commission in 2011. It involves the computer system developed for assessment and prediction of radiological emergencies consequences in the ChEZ ensuring the protection of personnel and the population living near its borders. The system assesses radiation situation under both normal conditions in the ChEZ and radiological emergencies which result in considerable radionuclides emission into the air (accidents at radiation hazardous objects, extreme weather conditions). Three different types of radionuclides release sources can be considered in the software package. So it is based on a set of different models of emission, atmospheric transport and deposition of radionuclides: 1) mesoscale model of radionuclide atmospheric transport LEDI for calculations of the radionuclides emission from stacks and buildings; 2) model of atmospheric transport and deposition of radionuclides due to anthropogenic resuspension from contaminated area (area surface source model) as a result of construction and excavation activity, heavy traffic etc.; 3) model of resuspension, atmospheric transport and deposition of radionuclides during grassland and forest fires in the ChEZ. The system calculates the volume and surface

  15. Irradiated fuel behavior under accident heating conditions and correlation with fission gas release and swelling model (Chicago)

    International Nuclear Information System (INIS)

    We analyse the mixed oxide fast fuel response to off normal conditions obtained by means of an out-of-pile transient simulation apparatus designed to provide direct observations (temperature, pressure, fuel motion) of fuel fission gas phenomena that might occur during the transients. The results are concerning fast transient tests (0,1 to 1 second) obtained with high gas concentration irradiated fuel (4 to 7 at % burn up, 0,4 cm3Xe + Kr /g.UPuO2). The kinetics of fission gas release during the transients have been directly measured and then compared with the calculated results issued of the Chicago model. This model agrees, quite well, with other experiments done in the silene prompt reactor. Other gases than xenon and krypton (such as hydrogen and carbon monoxide) do not play any role in fuel behavior, since they have been completely ruled out

  16. Tchernobyl accident

    International Nuclear Information System (INIS)

    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

  17. Accident: Reminder

    CERN Multimedia

    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

  18. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis

    Directory of Open Access Journals (Sweden)

    Eleni Tani

    2016-04-01

    Full Text Available Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11 on glyphosate susceptible (GS and glyphosate resistant (GR horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha−1 and high rates (4×, 8×, measured at an early one day after treatment (DAT and a later stage (four DAT of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C. GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation and molecularly (expression of EPSPS and ABC-genes like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance.

  19. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis.

    Science.gov (United States)

    Tani, Eleni; Chachalis, Demosthenis; Travlos, Ilias S; Bilalis, Dimitrios

    2016-04-20

    Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light) on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11) on glyphosate susceptible (GS) and glyphosate resistant (GR) horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha(-1)) and high rates (4×, 8×), measured at an early one day after treatment (DAT) and a later stage (four DAT) of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C). GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation) and molecularly (expression of EPSPS and ABC-genes) like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance.

  20. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis

    Science.gov (United States)

    Tani, Eleni; Chachalis, Demosthenis; Travlos, Ilias S.; Bilalis, Dimitrios

    2016-01-01

    Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light) on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11) on glyphosate susceptible (GS) and glyphosate resistant (GR) horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha−1) and high rates (4×, 8×), measured at an early one day after treatment (DAT) and a later stage (four DAT) of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C). GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation) and molecularly (expression of EPSPS and ABC-genes) like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance. PMID:27104532

  1. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis.

    Science.gov (United States)

    Tani, Eleni; Chachalis, Demosthenis; Travlos, Ilias S; Bilalis, Dimitrios

    2016-01-01

    Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light) on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11) on glyphosate susceptible (GS) and glyphosate resistant (GR) horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha(-1)) and high rates (4×, 8×), measured at an early one day after treatment (DAT) and a later stage (four DAT) of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C). GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation) and molecularly (expression of EPSPS and ABC-genes) like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance. PMID:27104532

  2. The Role of Trace Evidence in the Identification of Air-Conditioning Leakage Accident%微量物证在空调漏电事故鉴定中的作用

    Institute of Scientific and Technical Information of China (English)

    沈胜凡; 张旭; 孙芳荣; 陈鹏浩; 高伟

    2014-01-01

    通过对事故现场勘验、检测,找出了空调漏电的原因。表明空调故障检修时必须按章操作,同时强调空调安装系统接地是必须的。%We invest the accident scene,detect the air conditioning,and find the reason for the air conditioning leakage accidents.Through the process of the investing,we know that we must go by the operating system when the air conditioning maintenance.While it is necessary for the air conditioning system gets ground.

  3. Modeling alternative clad behavior for accident tolerant systems

    International Nuclear Information System (INIS)

    The US Department of Energy Fuel Cycle Research and Development program has a key goal of helping develop accident tolerant fuels (ATF) through investigating fuel and clad forms. In the current work thermochemical modeling and experiment are being used to assess fuel and clad alternatives. Cladding alternatives that have promise to improve fuel performance under accident conditions include the FeCrAl family of alloys and SiC-based composites. These are high strength and radiation resistant alloys and ceramics that have increased resistance to oxidation as compared to zirconium alloys. Accident modeling codes have indicated substantially increased time to failure and resulting effects. In the current work the thermochemical behavior of these materials are being assessed and the work reported here. (author)

  4. Models and criteria for prediction of Deflagration-to-Detonation Transition (DDT) in hydrogen-air-steam systems under severe accident conditions. Final report

    International Nuclear Information System (INIS)

    The European Commission in Brussels supported a joint project on Deflagration-to-Detonation Transition (DDT) studies for hydrogen safety within the framework programme on nuclear fission safety. The project was initiated by the Forschungszentrum Juelich based on the results of a pilot project. The following main project was coordinated by the Freie Universitaet Berlin involving seven european partners. The partners came from universities, research centers and industry, as follows: FU-Berlin, RWTH-Aachen, CNRS-Marseille, IPSN-Saclay, FZ-Juelich, FZ-Karlsruhe, and NNC-Knutsford, which worked closely together. The working period was two years (1997-1998). The aim of the project was to develop models and criteria for prediction of deflagration-to-detonation transition (DDT) in hydrogen-air-steam systems under severe accident conditions. The results obtained are documented in this final report, which was finished in 1999. The report consists of seven chapters, concerning: - Introduction - Experimental Investigations - Modelling and Numerics - Validation - Mitigation - Further Deliverables - Summary and Conclusion. The final report presents special experimental, theoretical, and computational aspects of the complex DDT phenomena for hydrogen safety studies, and it should be a solid basis for end user applications and further developments. (orig.)

  5. Transportation accidents

    International Nuclear Information System (INIS)

    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

  6. Proceedings of the CSNI workshop on International Standard Problem 48 - Analysis of 1:4-scale prestressed concrete containment vessel model under severe accident conditions

    International Nuclear Information System (INIS)

    At the CSNI meeting in June 2002, the proposal for an International Standard Problem on containment integrity (ISP 48) based on the NRC/NUPEC/Sandia test was approved. Objectives were to extend the understanding of capacities of actual containment structures based on results of the recent PCCV Model test and other previous research. The ISP was sponsored by the USNRC, and results had been made available thanks to NUPEC and to the USNRC. Sandia National Laboratory was contracted to manage the technical aspects of the ISP. At the end of the ISP48, a workshop was organized in Lyon, France on April 6-7, 2005 hosted by Electricite de France. Its overall objective was to present results obtained by participants in the ISP 48 and to assess the current practices and the state of the art with respect to the calculation of concrete structures under severe accident conditions. Experience from other areas in civil engineering related to the modelling of complex structures was greatly beneficial to all. Information obtained as a result of this assessment were utilized to develop a consensus on these calculations and identify issues or 'gaps' in the present knowledge for the primary purpose of formulating and prioritizing research needs on this topic. The ISP48 exercise was published in the report referenced NEA/CSNI/R(2005)5 in 3 volumes. Volume 1 contains the synthesis of the exercise; Volumes 2 and 3 contain individual contributions of participating organizations. The CSNI Working Group on the Integrity and Ageing and in particular its sub-group on the behaviour of concrete structures has produced extensive material over the last few years. The complete list of references is given in this document. These proceedings gather the papers and presentations given by the participants at the Lyon workshop

  7. Reactor accident in Chernobyl

    International Nuclear Information System (INIS)

    The bibliography contains 1568 descriptions of papers devoted to Chernobylsk accident and recorded in ''INIS Atomindex'' to 30 June 1990. The descriptions were taken from ''INIS Atomindex'' and are presented in accordance with volumes of this journal (chronology of recording). Therefore all descriptions have numbers showing first the number of volume and then the number of record. The bibliography has at the end the detailed subject index consisting of 465 main headings and a lot of qualifiers. Some of them are descriptors taken from ''INIS Atomindex'' and some are key words taken from natural language. The index is in English as descriptions in the bibliography. (author)

  8. Effect of culturing conditions on the expression of key enzymes in the proteolytic system of Lactobacillus bulgaricus.

    Science.gov (United States)

    Hou, Jun-cai; Liu, Fei; Ren, Da-xi; Han, Wei-wei; Du, Yue-ou

    2015-04-01

    The proteolytic system of Lactobacillus bulgaricus breaks down milk proteins into peptides and amino acids, which are essential for the growth of the bacteria. The aim of this study was to determine the expressions of seven key genes in the proteolytic system under different culturing conditions (different phases, initial pH values, temperatures, and nitrogen sources) using real-time polymerase chain reaction (RT-PCR). The transcriptions of the seven genes were reduced by 30-fold on average in the stationary phase compared with the exponential growth phase. The transcriptions of the seven genes were reduced by 62.5-, 15.0-, and 59.0-fold in the strains KLDS 08006, KLDS 08007, and KLDS 08012, respectively, indicating that the expressions of the seven genes were significantly different among strains. In addition, the expressions of the seven genes were repressed in the MRS medium containing casein peptone. The effect of peptone supply on PepX transcription was the weakest compared with the other six genes, and the impact on OppD transcription was the strongest. Moreover, the expressions of the seven genes were significantly different among different strains (PLactobacillus bulgaricus at the transcription level.

  9. A Narrow-Linewidth Atomic Line Filter for Free Space Quantum Key Distribution under Daytime Atmospheric Conditions

    Science.gov (United States)

    Brown, Justin; Woolf, David; Hensley, Joel

    2016-05-01

    Quantum key distribution can provide secure optical data links using the established BB84 protocol, though solar backgrounds severely limit the performance through free space. Several approaches to reduce the solar background include time-gating the photon signal, limiting the field of view through geometrical design of the optical system, and spectral rejection using interference filters. Despite optimization of these parameters, the solar background continues to dominate under daytime atmospheric conditions. We demonstrate an improved spectral filter by replacing the interference filter (Δν ~ 50 GHz) with an atomic line filter (Δν ~ 1 GHz) based on optical rotation of linearly polarized light through a warm Rb vapor. By controlling the magnetic field and the optical depth of the vapor, a spectrally narrow region can be transmitted between crossed polarizers. We find that the transmission is more complex than a single peak and evaluate peak transmission as well as a ratio of peak transmission to average transmission of the local spectrum. We compare filters containing a natural abundance of Rb with those containing isotopically pure 87 Rb and 85 Rb. A filter providing > 95 % transmission and Δν ~ 1.1 GHz is achieved.

  10. Methodological basis for qualification of the main steam line isolation valve in the beyond design basis accident conditions of expiration of steam-water mixture

    International Nuclear Information System (INIS)

    The work presents the computational and empirical methods and performance criteria for qualification of the main steam-isolation valve (MSIV) in accident scenarios with the expiration of steam-water mixture from the steam generator. Expiration of steam mixture through MSIV is possible in the beyond design basis accidents with inter loop leaks with full failure of functions of pressure control and/or isolation for emergency steam generator feed water. As a result of the preliminary analysis by the proposed method, the qualification criteria were determined for the modes of steam-water mixture expiration through MSIV at stable processes and surge

  11. Guidelines for calculating radiation doses to the public from a release of airborne radioactive material under hypothetical accident conditions in nuclear reactors

    International Nuclear Information System (INIS)

    This Standard provides guidelines and a methodology for calculating effective doses and thyroid doses to people (either individually or collectively) in the path of airborne radioactive material released from a nuclear facility following a hypothetical accident. The specific radionuclides considered in the Standard are those associated with substances having the greatest potential for becoming airborne in reactor accidents (eg, tritium (HTO), noble gases and their daughters (Kr-Rb, Xe-Cs), and radioiodines (I)); and certain radioactive particulates (eg, Cs, Ru, Sr, Te) that may become airborne under exceptional circumstances

  12. Systematics of Reconstructed Process Facility Criticality Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Pruvost, N.L.; McLaughlin, T.P.; Monahan, S.P.

    1999-09-19

    The systematics of the characteristics of twenty-one criticality accidents occurring in nuclear processing facilities of the Russian Federation, the United States, and the United Kingdom are examined. By systematics the authors mean the degree of consistency or agreement between the factual parameters reported for the accidents and the experimentally known conditions for criticality. The twenty-one reported process criticality accidents are not sufficiently well described to justify attempting detailed neutronic modeling. However, results of classic hand calculations confirm the credibility of the reported accident conditions.

  13. The role of radiation protection in the rehabilitation of living conditions in contaminated territories after a nuclear accident or a radiological event

    International Nuclear Information System (INIS)

    The implementation of radiation protection programmes in long -term contaminated territories is raising difficult technical, methodological, but also ethical questions, which commit the responsibility of the radiation protection professionals and the way they are exercising their expertise in such situation. The presence of contamination in the environment is a new reality which is profoundly affecting the living conditions of the population in all aspects: health, environment but also the psychological, social and economical cultural dimensions of daily life. In such a context, the classical radiation protection approach is inoperative to restore the normality of the ante accident situation On the contrary, the scientific and technological expertise and the prescriptive administrative arrangements, including the radiation protection ones, which are heavily mobilized to respond to the many challenges facing the society induce a progressive de -qualification of the environment and goods and a loss of control of the situation by the population which turn into a social depression. The paper illustrates how radiation protection programmes for managing long term contaminated territories have an ambivalent impact: on the one hand they ensure the protection of the population against the potential health impacts of radiations, on the other hand they re -enforce the loss of control, de-qualification and exclusion processes which results in a weakening of the resilience capacity of the population and the territories. The recent experience of co-expertise and co-operation implemented in the contaminated territories of Belarus have demonstrated that the direct engagement of local professionals and the population in the daily management of the radiological situation is not only feasible but also necessary to stop this vicious circle of loss of control and exclusion. To be effective and sustainable this engagement must rely on the diffusion among the population of a 'practical

  14. Guidelines for calculating radiation doses to the public from a release of airborne radioactive material under hypothetical accident conditions in nuclear reactors

    International Nuclear Information System (INIS)

    This standard provides guidelines and a methodology for calculating effective doses and thyroid doses to people (either individually or collectively) in the path of airborne radioactive material released from a nuclear facility following a hypothetical accident. The radionuclides considered are those associated with substances having the greatest potential for becoming airborne in reactor accidents: tritium (HTO), noble gases and their daughters, radioiodines, and certain radioactive particulates (Cs, Ru, Sr, Te). The standard focuses on the calculation of radiation doses for external exposures from radioactive material in the cloud; internal exposures for inhalation of radioactive material in the cloud and skin penetration of tritium; and external exposures from radionuclides deposited on the ground. It uses as modified Gaussian plume model to evaluate the time-integrated concentration downwind. (52 refs., 12 tabs., 21 figs.)

  15. Occupational Radiation Protection in Severe Accident Management

    International Nuclear Information System (INIS)

    protection job coverage during severe accident response. The IAEA defines a 'Severe Accident' as a beyond design basis accident comprising of accident conditions more severe than a design basis accident, involving significant core degradation. Preparation of the report The expert group met several times to share their experience and develop an interim (preliminary) report by the end of 2013. The content of the report is thus based on current reflections and action plans undertaken by the ISOE participating utilities and regulatory authorities to improve the emergency response plans in the event of a severe nuclear accident from the point of view of occupational radiation protection. A specific attention has been given to the analysis of past nuclear accidents (TMI-2, USA-1979; Chernobyl, USSR-1986 and Fukushima Daiichi, Japan-2011) and to the integration of the occupational radiation protection (ORP) lessons learned from these accidents into the various chapters of the report (See synthesis of these lessons learned in Appendix-1). To finalize the report, an international workshop was organized in 2014 to present and discuss the content of the interim version and share national experiences on best occupational RP management practices and protocols for optimum RP job coverage during severe accident, initial response and recovery efforts (see Appendix-2). The workshop notably allowed to improve and complete the report which has then be submitted to the ISOE Management Board for approval. This report comprises five main chapters. Chapter 2 provides essential information on radiation protection management and organisation. Chapter 3 establishes the goal of radiation protection training and exercises related to severe accident management. Chapter 4 discusses facility characteristics that must be considered when planning actions in response to a severe accident. Chapter 5 introduces an overall approach for the protection of workers / responders with its interpretation and

  16. Kiche; A Simulation tool for kinetics of iodine chemistry in the containment of light water reactors under severe accident conditions (Contract research)

    OpenAIRE

    森山 清史; 丸山 結; 中村 秀夫

    2011-01-01

    An iodine chemistry simulation tool, Kiche, was developed for analyses of chemical kinetics relevant to iodine volatilization in the containment vessel of light water reactors (LWRs) during a severe accident. It consists of a Fortran code to solve chemical kinetics models, reaction databases written in plain text format, and peripheral tools to convert the reaction databases into Fortran codes. Potential advantages of Kiche are the text format reaction database separated from the code that pr...

  17. Accident knowledge and emergency management

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Accident knowledge and emergency management

    International Nuclear Information System (INIS)

    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

  19. Accidents and human factors

    International Nuclear Information System (INIS)

    When the TMI accident occurred it was 4 a.m., an hour when the error potential of the operators would have been very high. The frequency of car and train accidents in Japan is also highest between 4 a.m. and 6 a.m. The error potential may be classified into five phases corresponding to the electroencephalogramic pattern (EEG). At phase 0, when the delta wave appears, a person is unconscious and in deep sleep; at phase I, when the theta wave appears, he is very tired, sleepy and subnormal; at phase II, when the alpha wave appears, he is normal, relaxed and passive; at phase III, when the beta wave appears, he is normal, clear-minded and active; at phase IV, when the strong beta or epileptic wave appears, he is hypernormal, excited and incapable of normal judgement. Should an accident occur at phase II, the brain condition may jump to phase IV. At this phase the error or accident potential is maximum. The response of the human brain to different types of noises and signals may vary somewhat for different individuals and for different groups of people. Therefore, the possibility that such differences in brain functions may influence the mental structure would be worthy of consideration in human factors and in the design of man-machine systems. Human reliability and performance would be affected by many factors: medical, physiological and psychological, etc. The uncertainty involved in human factors may not necessarily be probabilistic, but fuzzy. Therefore, it would be important to develop a theory by which both non-probabilistic uncertainties, or fuzziness, of human factors and the probabilistic properties of machines can be treated consistently. From the mathematical point of view, probabilistic measure is considered a special case of fuzzy measure. Therefore, fuzzy set theory seems to be an effective tool for analysing man-machine systems. To minimize human error and the possibility of accidents, new safety systems should not only back up man and make up for his

  20. Nuclear accident dosimetry intercomparison studies.

    Science.gov (United States)

    Sims, C S

    1989-09-01

    Twenty-two nuclear accident dosimetry intercomparison studies utilizing the fast-pulse Health Physics Research Reactor at the Oak Ridge National Laboratory have been conducted since 1965. These studies have provided a total of 62 different organizations a forum for discussion of criticality accident dosimetry, an opportunity to test their neutron and gamma-ray dosimetry systems under a variety of simulated criticality accident conditions, and the experience of comparing results with reference dose values as well as with the measured results obtained by others making measurements under identical conditions. Sixty-nine nuclear accidents (27 with unmoderated neutron energy spectra and 42 with eight different shielded spectra) have been simulated in the studies. Neutron doses were in the 0.2-8.5 Gy range and gamma doses in the 0.1-2.0 Gy range. A total of 2,289 dose measurements (1,311 neutron, 978 gamma) were made during the intercomparisons. The primary methods of neutron dosimetry were activation foils, thermoluminescent dosimeters, and blood sodium activation. The main methods of gamma dose measurement were thermoluminescent dosimeters, radiophotoluminescent glass, and film. About 68% of the neutron measurements met the accuracy guidelines (+/- 25%) and about 52% of the gamma measurements met the accuracy criterion (+/- 20%) for accident dosimetry. PMID:2777549

  1. Estimation of molecular carriers of electrons in mitochondria of adrenal cortex under conditions of long-term permanent action of low-intensive ionizing radiation after the accident at the Chernobyl NPP

    International Nuclear Information System (INIS)

    By EPR at 77K, we study molecular carriers of electrons in mitochondria of adrenal cortex in animals under conditions of the chronic action of low-dose ionizing irradiation from incorporated radionuclides related to the accident at the Chernobyl NPP and have found a significant decrease in the content of adrenodoxine which is a molecular carrier of electrons in the system of steroid hydroxylation. The last can play an important role in the mechanism of growth of neoplasms in adrenal glands, ovarial, and mammary glands

  2. Monitoring severe accidents using AI techniques

    International Nuclear Information System (INIS)

    After the Fukushima nuclear accident in 2011, there has been increasing concern regarding severe accidents in nuclear facilities. Severe accident scenarios are difficult for operators to monitor and identify. Therefore, accurate prediction of a severe accident is important in order to manage it appropriately in the unfavorable conditions. In this study, artificial intelligence (AI) techniques, such as support vector classification (SVC), probabilistic neural network (PNN), group method of data handling (GMDH), and fuzzy neural network (FNN), were used to monitor the major transient scenarios of a severe accident caused by three different initiating events, the hot-leg loss of coolant accident (LOCA), the cold-leg LOCA, and the steam generator tube rupture in pressurized water reactors (PWRs). The SVC and PNN models were used for the event classification. The GMDH and FNN models were employed to accurately predict the important timing representing severe accident scenarios. In addition, in order to verify the proposed algorithm, data from a number of numerical simulations were required in order to train the AI techniques due to the shortage of real LOCA data. The data was acquired by performing simulations using the MAAP4 code. The prediction accuracy of the three types of initiating events was sufficiently high to predict severe accident scenarios. Therefore, the AI techniques can be applied successfully in the identification and monitoring of severe accident scenarios in real PWRs.

  3. Simulations of the design basis accident at conditions of power increase and the o transient of MSIV at overpressure conditions of the Laguna Verde Power Station; Simulaciones del accidente base de diseno a condiciones de aumento de potencia y del transitorio de cierre de MSIV a condiciones de sobrepresion de la Central Laguna Verde

    Energy Technology Data Exchange (ETDEWEB)

    Araiza M, E.; Nunez C, A. [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico)

    2001-07-01

    This document presents the analysis of the simulation of the loss of coolant accident at uprate power conditions, that is 2027 MWt (105% of the current rated power of 1931MWt). This power was reached allowing an increase in the turbine steam flow rate without changing the steam dome pressure value at its rated conditions (1020 psiaJ. There are also presented the results of the simulation of the main steam isolation va/ve transient at overpressure conditions 1065 psia and 1067 MWt), for Laguna Verde Nuclear Power Station. Both simulations were performed with the best estimate computer code TRA C BF1. The results obtained in the loss of coolant accident show that the emergency core coolant systems can recover the water level in the core before fuel temperature increases excessively, and that the peak pressure reached in the drywell is always below its design pressure. Therefore it is concluded that the integrity of the containment is not challenged during a loss of coolant accident at uprate power conditions.The analysis of the main steam isolation valve transients at overpressure conditions, and the analysis of the particular cases of the failure of one to six safety relief valves to open, show that the vessel peak pressures are below the design pressure and have no significant effect on vessel integrity. (Author)

  4. Fukushima accident study using MELCOR

    Institute of Scientific and Technical Information of China (English)

    Randall O Gauntt

    2013-01-01

    The accidents at the Fukushima Daiichi nuclear power station stunned the world as the sequences played out over severals days and videos of hydrogen explosions were televised as they took place.The accidents all resulted in severe damage to the reactor cores and releases of radioactivity to the environment despite heroic measures had taken by the operating personnel.The following paper provides some background into the development of these accidents and their root causes,chief among them,the prolonged station blackout conditions that isolated the reactors from their ultimate heat sink — the ocean.The interpretations given in this paper are summarized from a recently completed report funded by the United States Department of Energy (USDOE).

  5. 10 CFR 50.67 - Accident source term.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Accident source term. 50.67 Section 50.67 Energy NUCLEAR... Conditions of Licenses and Construction Permits § 50.67 Accident source term. (a) Applicability. The... to January 10, 1997, who seek to revise the current accident source term used in their design...

  6. Nuclear accident impact on the ecological environment

    International Nuclear Information System (INIS)

    This article reviewed the eco-environmental behavior of radionuclides released into the environment by nuclear explosion and nuclear accidents, especially of several key radionuclides with biological significance, including 137Cs, 95Zr, 90Sr, 131I, 3H and 14C, in order to correctly understand the case of nuclear accidents and its pollution, maintain the social stable, and provide suitable measures for environmental protection and safety. (author)

  7. Porosity effects during a severe accident

    Energy Technology Data Exchange (ETDEWEB)

    Cazares R, R. I. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Posgrado en Energia y Medio Ambiente, San Rafael Atlixco 186, Col. Vicentina, 09340 Ciudad de Mexico (Mexico); Espinosa P, G.; Vazquez R, A., E-mail: ricardo-cazares@hotmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Area de Ingenieria en Recursos Energeticos, San Rafael Atlixco 186, Col. Vicentina, 09340 Ciudad de Mexico (Mexico)

    2015-09-15

    The aim of this work is to study the behaviour of porosity effects on the temporal evolution of the distributions of hydrogen concentration and temperature profiles in a fuel assembly where a stream of steam is flowing. The analysis considers the fuel element without mitigation effects. The mass transfer phenomenon considers that the hydrogen generated diffuses in the steam by convection and diffusion. Oxidation of the cladding, rods and other components in the core constructed in zirconium base alloy by steam is a critical issue in LWR accident producing severe core damage. The oxygen consumed by the zirconium is supplied by the up flow of steam from the water pool below the uncovered core, supplemented in the case of PWR by gas recirculation from the cooler outer regions of the core to hotter zones. Fuel rod cladding oxidation is then one of the key phenomena influencing the core behavior under high-temperature accident conditions. The chemical reaction of oxidation is highly exothermic, which determines the hydrogen rate generation and the cladding brittleness and degradation. The heat transfer process in the fuel assembly is considered with a reduced order model. The Boussinesq approximation was applied in the momentum equations for multicomponent flow analysis that considers natural convection due to buoyancy forces, which is related with thermal and hydrogen concentration effects. The numerical simulation was carried out in an averaging channel that represents a core reactor with the fuel rod with its gap and cladding and cooling steam of a BWR. (Author)

  8. Supervisor's accident investigation handbook

    International Nuclear Information System (INIS)

    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

  9. Technical Requirements and Principles for the Standards Development of the Key Parts for Rotor Air-conditioning Compressors

    Institute of Scientific and Technical Information of China (English)

    Sun Min; Wen Yun; Fan Zhangzeng

    2011-01-01

    ntroductionSince 2000,air-conditioning sales continues to grow,and the development of air-conditioning market makes a booming market of compressor.At the present time,compressor production rising all the way,and the sales steps up the new steps constantly.Tendency chart is shown in figure 1.Rotor compressor with its simple structure,small volume,light weight,easy processed mechanical parts,reliable operation and other excellent characteristics occupied the dominant position in the market.Compared with reciprocating compressor on the same application situation,decreased in the size by 40%~50%,weight was reduced by 40%~50%.But there were also disadvantages,mainly large friction loss,friction power consumption was about 10%of compressor's total power input.

  10. General Aspects of the JCO Criticality Accident

    International Nuclear Information System (INIS)

    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

  11. Business incubation in a university as a key condition for the formation of innovational micro entrepreneurship in a region

    Directory of Open Access Journals (Sweden)

    Anatoliy Viktorovich Grebenkin

    2012-09-01

    Full Text Available This paper substantiates the hypothesis of the special role of universities in creating an environment of innovational micro entrepreneurship in a region. The role of business incubators is allocated; the algorithm for selecting projects is described. The results of a three-year organizational and economic experiment (with the changing conditions on the functioning of the student business incubator in the Ural State University are shown. Various models of the selection of ideas and projects for different cycles of incubation areimplemented. A decision on theestablishment of the Entrepreneurship Center in theInstitute of Management and Entrepreneurship is made. The Center’s main task is to form a series of events to support continuous generation of students’ business ideas, finding resonant response with the University experts and representatives of business environment in the region. A student in the business incubation system plays a new role for a Russian university — a role of a catalyst, i.e., directly acts as an element of positive feedback in the innovational system. It is shown that the catalytic path of the establishment and development of small high-tech business — Science to Business (StB — leads to the phenomenon of resonance, i.e., sustainable innovation flow generated by the business incubator of the University. The poll of the USU students in 2009-2011 (a sample from 660 to 854 respondents confirmed their positive attitude towards entrepreneurship and allowed to estimate the structure of the factors that hamper to increase student participation in the innovational business. Three blocks of factors were identified: the reluctance to take risks, inaccessibility of material and financial resources and the turbulence of the environment. A system of monitoring students' attitudes towards entrepreneurship, which allows adjusting the curriculum and creating institutional conditions for activation of innovative entrepreneurship

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-01-31

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

  13. Framework for accident management

    International Nuclear Information System (INIS)

    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

  14. Application of Induced Containment Therapy with adapted protocol for home care and its contributions to the motor condition and patient rehabilitation after encephalic vascular accident

    Directory of Open Access Journals (Sweden)

    Daniela Tonús

    2015-09-01

    Full Text Available Introduction: Encephalic Vascular Accident (EVA is among the most important diseases that cause physical and functional limitations. Hemiplegia is the most common physical changes post-EVA, as compromises the upper and lower limbs at the same side of the body, characterized by a rigid pattern of the flexor muscles of the upper limb and the extensor muscles of the lower limb. The Induced Containment Therapy has been a major rehabilitation technique recently aiming to promote functional improvement of the hemiplegic limb of those who suffered EVA and enable performance and quality of life of the individual. Objective: This study aimed to identify the possible contributions of Induced Containment Therapy using a protocol adapted to technique application to the hemiplegic limb. Moreover, this research points out the influence of the environment interventions, which on the present study, occurred in the participant’s home. Method: this is a case study with exploratory feature. Results and Conclusion: The results indicated improvements in functional ability at the time of execution of the tasks and increased use of hemiplegic limb, increasing motor performance after applying the Induced Containment Therapy adapted protocol compared to the start of treatment

  15. Drilling the Mediterranean Messinian Evaporites to Answer Key Questions Related to Massive Microbial Dolomite Formation under Hypersaline Alkaline Conditions

    Science.gov (United States)

    McKenzie, Judith A.; Bontognali, Tomaso R. R.; Vasconcelos, Crisogono

    2014-05-01

    Deep-sea drilling in the Mediterranean during DSSP Leg 13 in 1970 revealed the basin-wide occurrence of a Messinian evaporite formation. This spectacular discovery was pursued further during a subsequent drilling program, DSDP Leg 42A, in 1975, which was designed, in part, to obtain continuous cores to study the evolution of the salinity crisis itself (Hsü, Montadert, et al., 1978). Specifically, drilling at a water depth of 4,088 m in the Ionian Sea, DSDP Site 374: Messina Abyssal Plain, penetrated about 80 m into the uppermost part of the Messinian upper evaporite formation. The sedimentary sequence comprises dolomitic mudstone overlying dolomitic mudstone/gypsum cycles, which in turn overlie anhydrite and halite. The non-fossiliferous dolomitic mudstone is generally rich in organic carbon, with TOC values ranging from 0.9% to 5.3%, of possible marine origin with a good source rock potential. Commonly laminated dolomitic mudstones contain preserved filamentous cyanobacterial remains suggesting that conditions were conducive for microbial mat growth. The Ca-dolomite, composed of fine-grained anhedral crystals in the size range of 2-4 μm, is probably a primary precipitate. The unusual interstitial brines of the dolomitic mudstone units have very high alkalinities with a low pH of 5 to 6. The Mg concentration (2250 mmoles/l) is extremely elevated, whereas the Ca concentration is nearly zero. Finally, the drilled evaporite sedimentary sequence was interpreted as being deposited in an alkaline lake/sea ("Lago Mare"), which covered the area during the latest Messinian. Projecting forward 40 years since the DSDP Leg 42A drilling campaign, research into the factors controlling dolomite precipitation under Earth surface conditions has led to the development of new models involving the metabolism of microorganisms and associated biofilms to overcome the kinetic inhibitions associated with primary dolomite precipitation. Together with laboratory experiments, microbial

  16. Compilation and response key points of emergency plan for dangerous chemical poisoning accident attention and response points%危险化学品中毒事故应急预案编制与响应关注要点

    Institute of Scientific and Technical Information of China (English)

    邢娟娟

    2011-01-01

    大工业的发展导致各类职业中毒事件的发生日益严重,除人员伤亡等影响外,也会对于社会公众安全带来影响.应急预案编制中强调应急准备的重要性和针对性.职业危害事故识别和分类分级处理以及对于社会公共安全影响的危机处理能力是应急工作中应该关注的重要内容.应急响应中强调第一目击者的处理能力的培养、现场的实时监测、事故报告与事态演变的持续预警、有效应急资源应对危机处理的能力.%The development of great industry lead to the occurrence of all kinds of occupational poisoning event, in addition to the increasingly serious casualties, the social public security will also be affected. Emergency plancom-pilation stressed in the the importance and relevance of emergency preparedness. Occupational hazard accidents I-dentification, classification and grading disposal, and the ability of handling crisis for public safety influence were the important content that should be focused on in emergency work. Emergency response stressed in the training of first witnesses processing ability that should be focused on in emergency work, on-site real-time monitoring, the accident report and the early warning of evolution, and the ability to effectively deal with crisis disposal of emergency resources.

  17. Laser accidents: Being Prepared

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Communication and industrial accidents

    OpenAIRE

    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...

  19. The Chernobyl accident consequences

    International Nuclear Information System (INIS)

    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.)

  20. Deepwater Horizon Accident Investigation Report

    Energy Technology Data Exchange (ETDEWEB)

    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

  1. Nuclear accidents and epidemiology

    International Nuclear Information System (INIS)

    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

  2. TMI-2 accident: core heat-up analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ardron, K.H.; Cain, D.G.

    1981-01-01

    This report summarizes NSAC study of reactor core thermal conditions during the accident at Three Mile Island, Unit 2. The study focuses primarily on the time period from core uncovery (approximately 113 minutes after turbine trip) through the initiation of sustained high pressure injection (after 202 minutes). The transient analysis is based upon established sequences of events; plant data; post-accident measurements; interpretation or indirect use of instrument responses to accident conditions.

  3. TMI-2 accident: core heat-up analysis

    International Nuclear Information System (INIS)

    This report summarizes NSAC study of reactor core thermal conditions during the accident at Three Mile Island, Unit 2. The study focuses primarily on the time period from core uncovery (approximately 113 minutes after turbine trip) through the initiation of sustained high pressure injection (after 202 minutes). The transient analysis is based upon established sequences of events; plant data; post-accident measurements; interpretation or indirect use of instrument responses to accident conditions

  4. Vehicle accidents related to sleep: a review

    OpenAIRE

    Horne, J.; Reyner, L.

    1999-01-01

    Falling asleep while driving accounts for a considerable proportion of vehicle accidents under monotonous driving conditions. Many of these accidents are related to work--for example, drivers of lorries, goods vehicles, and company cars. Time of day (circadian) effects are profound, with sleepiness being particularly evident during night shift work, and driving home afterwards. Circadian factors are as important in determining driver sleepiness as is the duration of the drive, but only ...

  5. Accident analysis in nuclear power plants

    International Nuclear Information System (INIS)

    The way the philosophy of Safety in Depth can be verified through the analysis of simulated accidents is shown. This can be achieved by verifying that the integrity of the protection barriers against the release of radioactivity to the environment is preserved even during accident conditions. The simulation of LOCA is focalized as an example, including a study about the associated environmental radiological consequences. (Author)

  6. Unconventional sources of plant information for accident management

    International Nuclear Information System (INIS)

    value and rate of change of key plant parameters can be directly measured or inferred from plant instrumentation. Even when the actual measured values for a particular instrument are less accurate than normally required, valuable information may still be obtained. Trends observed in the time-dependent behavior of that instrument can provide valuable information in how the accident is progressing. The failure of instruments themselves (especially those for which defined service condition requirements exist ) can yield information about plant status. Selected plant-specific examples of unconventional uses of plant information sources will be discussed in detail. Monitoring of secondary side cooling water system temperature can be used to infer core status and the ability to successfully remove heat to the ultimate heat sink. Containment/reactor vessel temperature can be used to infer core status and heat removal requirements. Tank pressure indication (e.g. pressurizer relief tank, waste gas surge tank) can be used to infer containment status. Tank level indication can be used to infer loss of inventory, system or containment over-pressurization. Water temperature increases, pump discharge pressures and pressure drops across pumps can be used to infer containment status. Use of process or area radiation monitors can be used to infer core status and fission product releases. Considerations regarding the use of unconventional information sources will be discussed. Plant- specific operator actions and procedural requirements may have significant impact on assessment of plant status. Instrument range capabilities may be significantly larger than the required/indicated range. Instrument accuracy requirements during an accident may be less stringent, allowing the use of marginally functional instruments. Information from locally indicated instrumentation may be unavailable due to harsh environments. (However, the presence of such environments would represent additional valuable

  7. Comparison of HRA methods based on WWER-1000 NPP real and simulated accident scenarios

    International Nuclear Information System (INIS)

    Full text: Adequate treatment of human interactions in probabilistic safety analysis (PSA) studies is a key to the understanding of accident sequences and their relative importance in overall risk. Human interactions with machines have long been recognized as important contributors to the safe operation of nuclear power plants (NPP). Human interactions affect the ordering of dominant accident sequences and hence have a significant effect on the risk of NPP. By virtue of the ability to combine the treatment of both human and hardware reliability in real accidents, NPP fullscope, multifunctional and computer-based simulators provide a unique way of developing an understanding of the importance of specific human actions for overall plant safety. Context dependent human reliability assessment (HRA) models, such as the holistic decision tree (HDT) and performance evaluation of teamwork (PET) methods, are the so-called second generation HRA techniques. The HDT model has been used for a number of PSA studies. The PET method reflects promising prospects for dealing with dynamic aspects of human performance. The paper presents a comparison of the two HRA techniques for calculation of post-accident human error probability in the PSA. The real and simulated event training scenario 'turbine's stop after loss of feedwater' based on standard PSA model assumptions is designed for WWER-1000 computer simulator and their detailed boundary conditions are described and analyzed. The error probability of post-accident individual actions will be calculated by means of each investigated technique based on student's computer simulator training archives

  8. Communication and industrial accidents

    NARCIS (Netherlands)

    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

  9. Accident investigation and analysis

    NARCIS (Netherlands)

    Kampen, J. van; Drupsteen, L.

    2013-01-01

    Many organisations and companies take extensive proactive measures to identify, evaluate and reduce occupational risks. However, despite these efforts things still go wrong and unintended events occur. After a major incident or accident, conducting an accident investigation is generally the next ste

  10. Severe accident testing of electrical penetration assemblies

    International Nuclear Information System (INIS)

    This report describes the results of tests conducted on three different designs of full-size electrical penetration assemblies (EPAs) that are used in the containment buildings of nuclear power plants. The objective of the tests was to evaluate the behavior of the EPAs under simulated severe accident conditions using steam at elevated temperature and pressure. Leakage, temperature, and cable insulation resistance were monitored throughout the tests. Nuclear-qualified EPAs were produced from D. G. O'Brien, Westinghouse, and Conax. Severe-accident-sequence analysis was used to generate the severe accident conditions (SAC) for a large dry pressurized-water reactor (PWR), a boiling-water reactor (BWR) Mark I drywell, and a BWR Mark III wetwell. Based on a survey conducted by Sandia, each EPA was matched with the severe accident conditions for a specific reactor type. This included the type of containment that a particular EPA design was used in most frequently. Thus, the D. G. O'Brien EPA was chosen for the PWR SAC test, the Westinghouse was chosen for the Mark III test, and the Conax was chosen for the Mark I test. The EPAs were radiation and thermal aged to simulate the effects of a 40-year service life and loss-of-coolant accident (LOCA) before the SAC tests were conducted. The design, test preparations, conduct of the severe accident test, experimental results, posttest observations, and conclusions about the integrity and electrical performance of each EPA tested in this program are described in this report. In general, the leak integrity of the EPAs tested in this program was not compromised by severe accident loads. However, there was significant degradation in the insulation resistance of the cables, which could affect the electrical performance of equipment and devices inside containment at some point during the progression of a severe accident. 10 refs., 165 figs., 16 tabs

  11. Severe accident testing of electrical penetration assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Clauss, D.B. (Sandia National Labs., Albuquerque, NM (USA))

    1989-11-01

    This report describes the results of tests conducted on three different designs of full-size electrical penetration assemblies (EPAs) that are used in the containment buildings of nuclear power plants. The objective of the tests was to evaluate the behavior of the EPAs under simulated severe accident conditions using steam at elevated temperature and pressure. Leakage, temperature, and cable insulation resistance were monitored throughout the tests. Nuclear-qualified EPAs were produced from D. G. O'Brien, Westinghouse, and Conax. Severe-accident-sequence analysis was used to generate the severe accident conditions (SAC) for a large dry pressurized-water reactor (PWR), a boiling-water reactor (BWR) Mark I drywell, and a BWR Mark III wetwell. Based on a survey conducted by Sandia, each EPA was matched with the severe accident conditions for a specific reactor type. This included the type of containment that a particular EPA design was used in most frequently. Thus, the D. G. O'Brien EPA was chosen for the PWR SAC test, the Westinghouse was chosen for the Mark III test, and the Conax was chosen for the Mark I test. The EPAs were radiation and thermal aged to simulate the effects of a 40-year service life and loss-of-coolant accident (LOCA) before the SAC tests were conducted. The design, test preparations, conduct of the severe accident test, experimental results, posttest observations, and conclusions about the integrity and electrical performance of each EPA tested in this program are described in this report. In general, the leak integrity of the EPAs tested in this program was not compromised by severe accident loads. However, there was significant degradation in the insulation resistance of the cables, which could affect the electrical performance of equipment and devices inside containment at some point during the progression of a severe accident. 10 refs., 165 figs., 16 tabs.

  12. The nuclear accident risk: a territorial approach

    International Nuclear Information System (INIS)

    How many people live in the vicinity of French nuclear power stations? Recent events - notably in Japan, but also in France - highlight the urgent need to be able to predict the possible effects of a nuclear accident on surrounding territories. Here, Ambroise Pascal identifies two key criteria for such an estimation: residential density and land use. (author)

  13. A Confirmatory Factor Analysis of Accidents Caused by the Motorcycle Aspect in Urban Area

    OpenAIRE

    Aji Suraji; Ngudi Tjahjono

    2012-01-01

    Traffic safety should be given the highest priority in order to reduce accidents. It seems that motorcycles give the most contribution to accidents than other vehicles, especially in urban area. The accidents are caused by poor condition factors of the motorcycles. Therefore, it is important to know the motorcycle aspect as a base to implement an action program to reduce accident risks. The objectives of this research were to analyze motorcycle aspect on accident risks including tires, brakes...

  14. Accidents with sulfuric acid

    Directory of Open Access Journals (Sweden)

    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.

  15. Persistence of airline accidents.

    Science.gov (United States)

    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.

  16. Accidents, risks and consequences

    International Nuclear Information System (INIS)

    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.)

  17. Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Appendix XI. Analysis of comments on the draft WASH-1400 report

    International Nuclear Information System (INIS)

    Information is presented concerning comments on reactor safety by governmental agencies and civilian organizations; reactor safety study methodology; consequence model; probability of accident sequences; and various accident conditions

  18. Strategy generator in computerized accident management support system

    International Nuclear Information System (INIS)

    An increased interest for research in the field of accident management of nuclear power plants can be noted. Several international programmes have been started in order to be able to understand the basic physical and chemical phenomena in accident conditions. A feasibility study has shown that it would be possible to design and develop a computerized support system for plant staff in accident situations. To achieve this goal the Halden Project has initiated a research programme on Computerized Accident Management Support (CAMS project). The aim is to utilize the capabilities of computerized tools to support the plant staff during the various accident stages. The system will include identification of the accident state, assessment of the future development of the accident and planning of accident mitigation strategies. A prototype is developed to support operators and the Technical Support Centre in decision making during serious accidents in nuclear power plants. A rule based system has been built to take care of the strategy generation. This system assists plant personnel in planning control proposals and mitigation strategies from normal operation to severe accident conditions. The idea of a safety objective tree and knowledge from the emergency procedures have been used. Future prediction requires good state identification of the plant status and some knowledge about the history of some critical variables. The information needs to be validated as well. Accurate calculations in simulators and a large database including all important information from the plant will help the strategy planning. (orig.). (40 refs., 20 figs.)

  19. Short-term selective alleviation of glucotoxicity and lipotoxicity ameliorates the suppressed expression of key β-cell factors under diabetic conditions.

    Science.gov (United States)

    Shimo, Naoki; Matsuoka, Taka-aki; Miyatsuka, Takeshi; Takebe, Satomi; Tochino, Yoshihiro; Takahara, Mitsuyoshi; Kaneto, Hideaki; Shimomura, Iichiro

    2015-11-27

    Alleviation of hyperglycaemia and hyperlipidemia improves pancreatic β-cell function in type 2 diabetes. However, the underlying molecular mechanisms are still not well clarified. In this study, we aimed to elucidate how the expression alterations of key β-cell factors are altered by the short-term selective alleviation of glucotoxicity or lipotoxicity. We treated db/db mice for one week with empagliflozin and/or bezafibrate to alleviate glucotoxicity and/or liptotoxicity, respectively. The gene expression levels of Pdx1 and Mafa, and their potential targets, insulin 1, Slc2a2, and Glp1r, were higher in the islets of empagliflozin-treated mice, and levels of insulin 2 were higher in mice treated with both reagents, than in untreated mice. Moreover, compared to the pretreatment levels, Mafa and insulin 1 expression increased in empagliflozin-treated mice, and Slc2a2 increased in combination-treated mice. In addition, empagliflozin treatment enhanced β-cell proliferation assessed by Ki-67 immunostaining. Our date clearly demonstrated that the one-week selective alleviation of glucotoxicity led to the better expression levels of the key β-cell factors critical for β-cell function over pretreatment levels, and that the alleviation of lipotoxicity along with glucotoxicity augmented the favorable effects under diabetic conditions. PMID:26471305

  20. ASTEC V2 severe accident integral code main features, current V2.0 modelling status, perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Chatelard, P., E-mail: patrick.chatelard@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSN-RES, B.250, Cadarache BP3 13115, Saint-Paul-lez-Durance, Cedex (France); Reinke, N.; Arndt, S. [Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbH, Schwertnergasse 1, 50677 Köln (Germany); Belon, S.; Cantrel, L.; Carenini, L.; Chevalier-Jabet, K.; Cousin, F. [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSN-RES, B.250, Cadarache BP3 13115, Saint-Paul-lez-Durance, Cedex (France); Eckel, J. [Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbH, Schwertnergasse 1, 50677 Köln (Germany); Jacq, F.; Marchetto, C.; Mun, C.; Piar, L. [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSN-RES, B.250, Cadarache BP3 13115, Saint-Paul-lez-Durance, Cedex (France)

    2014-06-01

    The severe accident integral code ASTEC, jointly developed since almost 20 years by IRSN and GRS, simulates the behaviour of a whole nuclear power plant under severe accident conditions, including severe accident management by engineering systems and procedures. Since 2004, the ASTEC code is progressively becoming the reference European severe accident integral code through in particular the intensification of research activities carried out in the frame of the SARNET European network of excellence. The first version of the new series ASTEC V2 was released in 2009 to about 30 organizations worldwide and in particular to SARNET partners. With respect to the previous V1 series, this new V2 series includes advanced core degradation models (issued from the ICARE2 IRSN mechanistic code) and necessary extensions to be applicable to Gen. III reactor designs, notably a description of the core catcher component to simulate severe accidents transients applied to the EPR reactor. Besides these two key-evolutions, most of the other physical modules have also been improved and ASTEC V2 is now coupled to the SUNSET statistical tool to make easier the uncertainty and sensitivity analyses. The ASTEC models are today at the state of the art (in particular fission product models with respect to source term evaluation), except for quenching of a severely damage core. Beyond the need to develop an adequate model for the reflooding of a degraded core, the main other mean-term objectives are to further progress on the on-going extension of the scope of application to BWR and CANDU reactors, to spent fuel pool accidents as well as to accidents in both the ITER Fusion facility and Gen. IV reactors (in priority on sodium-cooled fast reactors) while making ASTEC evolving towards a severe accident simulator constitutes the main long-term objective. This paper presents the status of the ASTEC V2 versions, focussing on the description of V2.0 models for water-cooled nuclear plants.

  1. Accident Tolerant Fuel Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Curtis Smith; Heather Chichester; Jesse Johns; Melissa Teague; Michael Tonks; Robert Youngblood

    2014-09-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about light water reactor design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway research and development (R&D) is to support plant decisions for risk-informed margins management by improving economics and reliability, and sustaining safety, of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced “RISMC toolkit” that enables more accurate representation of NPP safety margin. In order to carry out the R&D needed for the Pathway, the Idaho National Laboratory is performing a series of case studies that will explore methods- and tools-development issues, in addition to being of current interest in their own right. One such study is a comparative analysis of safety margins of plants using different fuel cladding types: specifically, a comparison between current-technology Zircaloy cladding and a notional “accident-tolerant” (e.g., SiC-based) cladding. The present report begins the process of applying capabilities that are still under development to the problem of assessing new fuel designs. The approach and lessons learned from this case study will be included in future Technical Basis Guides produced by the RISMC Pathway. These guides will be the mechanism for developing the specifications for RISMC tools and for defining how plant decision makers should propose and

  2. Accident tolerant fuel analysis

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis [Idaho National Laboratory; Chichester, Heather [Idaho National Laboratory; Johns, Jesse [Texas A& M University; Teague, Melissa [Idaho National Laboratory; Tonks, Michael Idaho National Laboratory; Youngblood, Robert [Idaho National Laboratory

    2014-09-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about light water reactor design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway research and development (R&D) is to support plant decisions for risk-informed margins management by improving economics and reliability, and sustaining safety, of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced ''RISMC toolkit'' that enables more accurate representation of NPP safety margin. In order to carry out the R&D needed for the Pathway, the Idaho National Laboratory is performing a series of case studies that will explore methods- and tools-development issues, in addition to being of current interest in their own right. One such study is a comparative analysis of safety margins of plants using different fuel cladding types: specifically, a comparison between current-technology Zircaloy cladding and a notional ''accident-tolerant'' (e.g., SiC-based) cladding. The present report begins the process of applying capabilities that are still under development to the problem of assessing new fuel designs. The approach and lessons learned from this case study will be included in future Technical Basis Guides produced by the RISMC Pathway. These guides will be the mechanism for developing the specifications for RISMC tools and for defining how plant

  3. REFORMATION OF THE GRAIN EXCHANGE OF RUSSIA, AS A KEY ELEMENT OF ADAPTATION OF GRAIN MULTINATIONAL CORPORATIONS IN THE CONDITIONS OF THE RUSSIAN ECONOMY

    Directory of Open Access Journals (Sweden)

    Dudinova E. E.

    2014-04-01

    Full Text Available Reformation of the grain exchange of Russia becomes a key aspect of strengthening of the reached line items, and also an entry into the new regional markets due to the need of development of an export potential of Russia within the international grain market. In this work basic elements of upgrade of the existing grain mechanism are considered (on basis of JSC National Mercantile Exchange, examples are given from practical operating activities of CME Group Inc (Group of the Chicago board of trade. The conclusion that consolidation of the Russian Federation, Ukraine and the Republic of Kazakhstan under the auspices of a single grain platform becomes a priority in development of export trade in the Black Sea pool, especially in the conditions of the fixed competition for the markets

  4. Modelling and analysis of severe accidents for VVER-1000 reactors

    OpenAIRE

    Tusheva, Polina

    2013-01-01

    Accident conditions involving significant core degradation are termed severe accidents /IAEA: NS-G-2.15/. Despite the low probability of occurrence of such events, the investigation of severe accident scenarios is an important part of the nuclear safety research. Considering a hypothetical core melt down scenario in a VVER-1000 light water reactor, the early in-vessel phase focusing on the thermal-hydraulic phenomena, and the late in-vessel phase focusing on the melt relocation into the re...

  5. Mapping patterns and characteristics of fatal road accidents in Israel

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Gitelman, Victoria; Bekhor, Shlomo

    2010-01-01

    elderly pedestrians crossed in urban areas; (v) accidents where mostly young children and teenagers cross roads in small villages. Feed-forward back-propagation neural networks indicate that demographic characteristics of both victims and drivers are the most relevant determinants, and other significant...... factors are the road conditions, the accident location in either urban or rural areas, the accident location in either sections or intersections, and the period of the day when the crash occurs....

  6. Soviet submarine accidents

    International Nuclear Information System (INIS)

    Although the Soviet Union has more submarines than the NATO navies combined, and the technological superiority of western submarines is diminishing, there is evidence that there are more accidents with Soviet submarines than with western submarine fleets. Whether this is due to inadequate crews or lower standards of maintenance and overhaul procedures is discussed. In particular, it is suggested that since the introduction of nuclear powered submarines, the Soviet submarine safety record has deteriorated. Information on Soviet submarine accidents is difficult to come by, but a list of some 23 accidents, mostly in nuclear submarines, between 1966 and 1986, has been compiled. The approximate date, class or type of submarine, the nature and location of the accident, the casualties and damage and the source of information are tabulated. (U.K.)

  7. Accident resistant transport container

    Science.gov (United States)

    Anderson, J.A.; Cole, K.K.

    The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

  8. Boating Accident Statistics

    Data.gov (United States)

    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...

  9. Analysis of Maximum Reasonably Foreseeable Accidents for the Yucca Mountain Draft Environmental Impact Statement (DEIS)

    Energy Technology Data Exchange (ETDEWEB)

    S.B. Ross; R.E. Best; S.J. Maheras; T.I. McSweeney

    2001-08-17

    Accidents could occur during the transportation of spent nuclear fuel and high-level radioactive waste. This paper describes the risks and consequences to the public from accidents that are highly unlikely but that could have severe consequences. The impact of these accidents would include those to a collective population and to hypothetical maximally exposed individuals (MEIs). This document discusses accidents with conditions that have a chance of occurring more often than 1 in 10 million times in a year, called ''maximum reasonably foreseeable accidents''. Accidents and conditions less likely than this are not considered to be reasonably foreseeable.

  10. FATAL ACCIDENT REPORTING SYSTEM (FARS)

    Science.gov (United States)

    The Fatal Accident Reporting System (FARS) database consist of three relational tables, containing data on automobile accidents on public U.S. roads that resulted in the death of one or more people within 30 days of the accident. Truck and trailer accidents are also included.

  11. Traffic Accidents on Slippery Roads

    DEFF Research Database (Denmark)

    Fonnesbech, J. K.; Bolet, Lars

    2014-01-01

    Police registrations from 65 accidents on slippery roads in normally Danish winters have been studied. The study showed: • 1 accident per 100 km when using brine spread with nozzles • 2 accidents per 100 km when using pre wetted salt • 3 accidents per 100 km when using kombi spreaders The results...

  12. Accident and emergency management

    International Nuclear Information System (INIS)

    There is an increasing potential for severe accidents as the industrial development tends towards large, centralised production units. In several industries this has led to the formation of large organisations which are prepared for accidents fighting and for emergency management. The functioning of these organisations critically depends upon efficient decision making and exchange of information. This project is aimed at securing and possibly improving the functionality and efficiency of the accident and emergency management by verifying, demonstrating, and validating the possible use of advanced information technology in the organisations mentioned above. With the nuclear industry in focus the project consists of five main activities: 1) The study and detailed analysis of accident and emergency scenarios based on records from incidents and rills in nuclear installations. 2) Development of a conceptual understanding of accident and emergency management with emphasis on distributed decision making, information flow, and control structure sthat are involved. 3) Development of a general experimental methodology for evaluating the effects of different kinds of decision aids and forms of organisation for emergency management systems with distributed decision making. 4) Development and test of a prototype system for a limited part of an accident and emergency organisation to demonstrate the potential use of computer and communication systems, data-base and knowledge base technology, and applications of expert systems and methods used in artificial intelligence. 5) Production of guidelines for the introduction of advanced information technology in the organisations based on evaluation and validation of the prototype system. (author)

  13. FUNDING OF ACCIDENT INSURANCE IN UKRAINE

    Directory of Open Access Journals (Sweden)

    O. Gamankova

    2016-03-01

    Full Text Available The paper deals with the peculiarities of financial provision of public and private accident insurance. Analyzes the methodology of forming insurance premium rates in private accident insurance. The study examines the practice of reforming the financial security of the state social insurance against accidents. The results show need to implement scientifically proven approach to determining premium rates in the state social insurance based on mathematical statistics and actuarial calculations to ensure that such conditions on the one hand, can insure the risk, and the other - to provide the insurer the ability to perform insurance obligations' commitments. One of the promising areas of improvement Accident Insurance determines to define increasing the role of the private sector to create and attraction of investments, financing, reduce costs, and provision of insurance services on insurance against accidents at a qualitatively higher level. The results show the need to consider the usefulness of a mixed provision of services to accident insurance under state or non-state system, and the viability and effectiveness of the combination of these systems.

  14. Cyclical Fluctuations in Workplace Accidents

    OpenAIRE

    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...

  15. Calculation of relative tube/tube support plate displacements in steam generators under accident condition loads using non-linear dynamic analysis methodologies

    International Nuclear Information System (INIS)

    A non-linear analysis has been performed to determine relative motions between tubes and tube support plates (TSP) during a steam line break (SLB) event for steam generators. The SLB event results in blowdown of steam and water out of the steam generator. The fluid blowdown generates pressure drops across the TSPS, resulting in out-of-plane motion. The SLB induced pressure loads are calculated with a computer program that uses a drift-flux modeling of the two-phase flow. In order to determine the relative tube/TSP motions, a nonlinear dynamic time-history analysis is performed using a structural model that considers all of the significant component members relative to the tube support system. The dynamic response of the structure to the pressure loads is calculated using a special purpose computer program. This program links the various substructures at common degrees of freedom into a combined mass and stiffness matrix. The program accounts for structural non-linearities, including potential tube and TSP interaction at any given tube position. The program also accounts for structural damping as part of the dynamic response. Incorporating all of the above effects, the equations of motion are solved to give TSP displacements at the reduced set of DOF. Using the displacement results from the dynamic analysis, plate stresses are then calculated using the detailed component models. Displacements form the dynamic analysis are imposed as boundary conditions at the DOF locations, and the finite element program then solves for the overall distorted geometry. Calculations are also performed to assure that assumptions regarding elastic response of the various structural members and support points are valid

  16. Radiation accidents and defence of population

    International Nuclear Information System (INIS)

    , harmonisation of loading, guarantee of people with remedies of individual defence, sanitary treatment, deactivation and etc.), radiation-dose metrical control, lowering of radioactive pollution level, special treatment apartments, technic, people, animals; radio metrical control of foodstuffs, water, evacuation of people; limitation and prohibition of living, economic activity and ets. It should be note, that is a danger of origin of radiation accident not connected with NPP in our Republic. Utilization of radiation in the different branches of our country national economy including in oil industry can create danger for irradiation of population and radioactive pollution of surroundings. That situation has been also redoubled by the Baku's oil supports concerning more quality of natural radioactive matters. For that reason in the industry environment oil and gas-extracting, oil refining enterprises there are radioactive pollution exceeding permissible levels. Such state stipulates irradiation of personal over NPP. At the same time radioactive pollution industry zone also can promote to radioactive pollution of adjoining living zone and there to exert unhealthy to population. Consequently, existing ecological conditions with such radiation accident can complicate radiation situation and so demand additional arrangement for defence of population. Transit transportation of radioactive matters via our territory is radioecological danger for our Republic. Some origins of radiation accidents could not happen with such transportation. An important danger for population's health of our Republic and its surroundings are possible accidents in Armenian NPP. As a result of work that NPP forms radioactive waste products. They can be buried on border territories and so through underground water can promote radioactive pollution of our Republic surroundings. Thus, questions of defence of population by radiation accidents are also actual for Azerbaijan

  17. Occupational Accidents: A Perspective of Pakistan Construction Industry

    Directory of Open Access Journals (Sweden)

    Tauha Hussain Ali

    2014-07-01

    Full Text Available It has been observed that the construction industry is one of the notorious industry having higher rate of fatalities and injuries. Resulting in higher financial losses and work hour losses, which are normally faced by this industry due to occuptional accidents. Construction industry has the highest occupational accidents rate recorded throughout the world after agriculture industry. The construction work site is often a busy place having an incredibly high account of activities taking place, where everyone is moving in frenzy having particular task assigned. In such an environment, occupational accidents do occur. This paper gives information about different types of occupational accidents & their causes in the construction industry of Pakistan. A survey has been carried out to identify the types of occupational accidents often occur at construction site. The impact of each occupational accident has also been identified. The input from the different stakeholders involved on the work site was analyzed using RIW (Relative Importance Weight method. The findings of this research show that ?fall from elevation, electrocution from building power and snake bite? are the frequent occupational accidents occur within the work site where as ?fall from elevation, struck by, snake bite and electrocution from faulty tool? are the occupational accident with high impact within the construction industry of Pakistan. The results also shows the final ranking of the accidents based on higher frequency and higher impact. Poor Management, Human Element and Poor Site Condition are found as the root causes leading to such occupational accidents. Hence, this paper

  18. Behaviour of fission products under severe PWR accident conditions. The VERCORS experimental programme-Part 3: Release of low-volatile fission products and actinides

    International Nuclear Information System (INIS)

    The VERCORS analytical programme consisted of a series of tests carried out on irradiated PWR fuel samples. The tests - funded jointly by EDF and IRSN - were carried out by the Commissariat a l'Energie Atomique (CEA) at their Grenoble site. They were performed in a hot cell belonging to the Active Materials Analysis Laboratory (LAMA). The general outline of the programme was set out in a first article (of a series of 3), which described the different levels of fission products (FP) volatility and their characteristics. This led to a classification into five main categories of volatility and/or behaviour: (1) Volatile FP including fission gases, iodine, caesium, antimony, tellurium, cadmium, rubidium and silver; (2) Semi-volatile FP, a category made up of molybdenum, rhodium, barium, palladium and technetium; (3) Low-volatile FP comprising ruthenium, cerium, strontium, yttrium, europium, niobium and lanthanum with generally low but significant release; (4) Non-volatile FP including zirconium, neodymium and praseodymium; and lastly (5) Actinides which group together uranium, plutonium, neptunium, americium and curium. The specific behaviour of fission gases and volatile FP is dealt with in the second article, which also includes the specific characteristics of volatile FP regarding transport. The main variables (i.e. temperature, which is the main variable at least until loss of sample geometry, oxidising-reducing conditions, burn-up, interactions with the cladding and/or the structural components, the nature of the fuel, and finally the state of the fuel) affecting the kinetics and/or the released fraction of these same FP could also be identified. This final article represents the Third Part of the series. It concerns the release of actinides and less volatile FP, in keeping with the classification by categories previously identified, which are as follows: (1) semi-volatile FP, comprising of Mo, Ba, Rh, Pd, Tc, (2) low-volatile FP, comprising of Sr, Y, Nb, Ru, La

  19. Interventions after serious reactor accidents

    International Nuclear Information System (INIS)

    Manifold and promising approaches to active measures to be taken during accidents were studied hypothetically at the HTR which already has outstanding inherent safety properties in respect of afterheat removal. Based on incident scenarios prepared for hypothetical air inleakage incidents, in particular into the core of the HTR module reactor, many and various peripheral conditions for intervention possibilities could be studied. In addition, intervention possibilities appropriate for the respective incidents were examined as to their feasibility and consequences to be expected after their application. From these studies suggestions were derived for verifying experiments. (orig./HP) With 66 refs., 24 tabs., 79 figs

  20. Accidents in nuclear ships

    Energy Technology Data Exchange (ETDEWEB)

    Oelgaard, P.L. [Risoe National Lab., Roskilde (Denmark)]|[Technical Univ. of Denmark, Lyngby (Denmark)

    1996-12-01

    This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10{sup -3} per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au).

  1. Accidents in nuclear ships

    International Nuclear Information System (INIS)

    This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10-3 per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au)

  2. Accident progression event tree analysis for postulated severe accidents at N Reactor

    International Nuclear Information System (INIS)

    A Level II/III probabilistic risk assessment (PRA) has been performed for N Reactor, a Department of Energy (DOE) production reactor located on the Hanford reservation in Washington. The accident progression analysis documented in this report determines how core damage accidents identified in the Level I PRA progress from fuel damage to confinement response and potential releases the environment. The objectives of the study are to generate accident progression data for the Level II/III PRA source term model and to identify changes that could improve plant response under accident conditions. The scope of the analysis is comprehensive, excluding only sabotage and operator errors of commission. State-of-the-art methodology is employed based largely on the methods developed by Sandia for the US Nuclear Regulatory Commission in support of the NUREG-1150 study. The accident progression model allows complex interactions and dependencies between systems to be explicitly considered. Latin Hypecube sampling was used to assess the phenomenological and systemic uncertainties associated with the primary and confinement system responses to the core damage accident. The results of the analysis show that the N Reactor confinement concept provides significant radiological protection for most of the accident progression pathways studied

  3. Modeling accident frequency in Denmark for improving road safety

    DEFF Research Database (Denmark)

    Lyckegaard, Allan; Hels, Tove; Kaplan, Sigal;

    the infrastructure characteristics and the traffic conditions of the road. The model can be used to point out high risk road segments and support road authorities in planning interventions for the improvement of road safety on Danish roads. The number of accidents on a road link was modeled using a count model after......Traffic accidents result in huge costs to society in terms of death, injury, lost productivity, and property damage. The main objective of the current study is the development of an accident frequency model that predicts the expected number of accidents on a given road segment, provided...... verifying the presence of overdispersion in the variance of the counts. The model relates the number of accidents to the characteristics of the infrastructure in terms of geometry and traffic in order to identify which risk factors and at which degree relate to the possibility of accident occurrence. Data...

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

    International Nuclear Information System (INIS)

    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.)

  5. Cause Analysis of Wuhan Tianheng Building Pile Accident

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The geological condition and the original structure feature and foundation design of Wuhan Tianheng building are described. The accident appearance of pile foundation in the construction execution of work is illustrated. The generating source of this pile foundation accident is analyzed in great details.``

  6. Scoping accident(s) for emergency planning

    International Nuclear Information System (INIS)

    At the request of the Conference of State Radiation Control Program Director's (CRCPD), in November 1976 the U.S. Nuclear Regulatory Commission formed a joint Task Force with representatives of the U.S. Environmental Protection Agency to answer a number of questions posed by the States regarding emergency planning. This Task Force held monthly meetings through November 1977. In December 1977 a draft report was prepared for limited distribution for review and comment by selected State and local organizations. The NRC/EPA Task Force deliberations centered on the CRCPD request for '... a determination of the most severe accident basis for which radiological emergency response plans should be developed by offsite agencies...' in the vicinity of nuclear power plants. Federal Interagency guidance to the States in this regard has been that the scoping accident should be the most serious conservatively analyzed accident considered for siting purposes, as exemplified in the Commission's Regulations at 10 CFR Part 100 and the NRC staffs Regulatory Guides 1.3 and 1.4, and as presented in license applicant's Safety Analysis Reports and the USNRC Staffs Safety Evaluation Reports. The draft report of the Task Force amplifies on this recommendation: to present a clearer picture of its import and introduces the concept of protective action zones (PAZs) within which detailed emergency plans should be developed; one zone for the plume exposure pathway and a second, larger zone for contamination pathways. The time dependence of potential releases and atmospheric transport, and important radionuclide groups of possible import are also discussed in the draft Task Force report. A status report regarding this effort, as of June 1978, will be presented. (author)

  7. conditions

    Directory of Open Access Journals (Sweden)

    M. Venkatesulu

    1996-01-01

    Full Text Available Solutions of initial value problems associated with a pair of ordinary differential systems (L1,L2 defined on two adjacent intervals I1 and I2 and satisfying certain interface-spatial conditions at the common end (interface point are studied.

  8. Dementia and Traffic Accidents

    DEFF Research Database (Denmark)

    Petersen, Jindong Ding; Siersma, Volkert; Nielsen, Connie Thurøe;

    2016-01-01

    BACKGROUND: As a consequence of a rapid growth of an ageing population, more people with dementia are expected on the roads. Little is known about whether these people are at increased risk of road traffic-related accidents. OBJECTIVE: Our study aims to investigate the risk of road traffic...... Central Research Register, and/or (2) at least one dementia diagnosis-related drug prescription registration in the Danish National Prescription Registry. Police-, hospital-, and emergency room-reported road traffic-related accidents occurred within the study follow-up are defined as the study outcome...... selection bias due to nonparticipation and loss to follow-up. Furthermore, this ensures that the study results are reliable and generalizable. However, underreporting of traffic-related accidents may occur, which will limit estimation of absolute risks....

  9. Psychical and social effects related to post-accident situations: some training of Chernobyl accident

    International Nuclear Information System (INIS)

    Some preliminary considerations on the psychic and societal dimensions related to post-accident situations connected to large scale and heavy land contamination are presented. This is done with the objective of exploring the role that these dimensions could play in the elaboration of new radiological protection principles and concepts in order to restore confidence among affected populations after a nuclear accident. It is important to facilitate the return to normal or, at least, acceptable living conditions, as soon as reasonably achievable, and to prevent the possible emergence of a post-accident crisis. A scheme is proposed for understanding the dynamics of the various phases after an accident, taking into account the collective response to the consequences as well as, the response to the countermeasures. (Author)

  10. A case study of electrostatic accidents in the process of oil-gas storage and transportation

    Science.gov (United States)

    Hu, Yuqin; Wang, Diansheng; Liu, Jinyu; Gao, Jianshen

    2013-03-01

    Ninety nine electrostatic accidents were reviewed, based on information collected from published literature. All the accidents over the last 30 years occurred during the process of oil-gas storage and transportation. Statistical analysis of these accidents was performed based on the type of complex conditions where accidents occurred, type of tanks and contents, and type of accidents. It is shown that about 85% of the accidents occurred in tank farms, gas stations or petroleum refineries, and 96% of the accidents included fire or explosion. The fishbone diagram was used to summarize the effects and the causes of the effects. The results show that three major reasons were responsible for accidents, including improper operation during loading and unloading oil, poor grounding and static electricity on human bodies, which accounted for 29%, 24% and 13% of the accidents, respectively. Safety actions are suggested to help operating engineers to handle similar situations in the future.

  11. A case study of electrostatic accidents in the process of oil-gas storage and transportation

    International Nuclear Information System (INIS)

    Ninety nine electrostatic accidents were reviewed, based on information collected from published literature. All the accidents over the last 30 years occurred during the process of oil-gas storage and transportation. Statistical analysis of these accidents was performed based on the type of complex conditions where accidents occurred, type of tanks and contents, and type of accidents. It is shown that about 85% of the accidents occurred in tank farms, gas stations or petroleum refineries, and 96% of the accidents included fire or explosion. The fishbone diagram was used to summarize the effects and the causes of the effects. The results show that three major reasons were responsible for accidents, including improper operation during loading and unloading oil, poor grounding and static electricity on human bodies, which accounted for 29%, 24% and 13% of the accidents, respectively. Safety actions are suggested to help operating engineers to handle similar situations in the future.

  12. Severe Accident Recriticality Analyses (SARA)

    Energy Technology Data Exchange (ETDEWEB)

    Frid, W. [Swedish Nuclear Power Inspectorate, Stockholm (Sweden); Hoejerup, F. [Risoe National Lab. (Denmark); Lindholm, I.; Miettinen, J.; Puska, E.K. [VTT Energy, Helsinki (Finland); Nilsson, Lars [Studsvik Eco and Safety AB, Nykoeping (Sweden); Sjoevall, H. [Teoliisuuden Voima Oy (Finland)

    1999-11-01

    Recriticality in a BWR has been studied for a total loss of electric power accident scenario. In a BWR, the B{sub 4}C control rods would melt and relocate from the core before the fuel during core uncovery and heat-up. If electric power returns during this time-window unborated water from ECCS systems will start to reflood the partly control rod free core. Recriticality might take place for which the only mitigating mechanisms are the Doppler effect and void formation. In order to assess the impact of recriticality on reactor safety, including accident management measures, the following issues have been investigated in the SARA project: 1. the energy deposition in the fuel during super-prompt power burst, 2. the quasi steady-state reactor power following the initial power burst and 3. containment response to elevated quasi steady-state reactor power. The approach was to use three computer codes and to further develop and adapt them for the task. The codes were SIMULATE-3K, APROS and RECRIT. Recriticality analyses were carried out for a number of selected reflooding transients for the Oskarshamn 3 plant in Sweden with SIMULATE-3K and for the Olkiluoto 1 plant in Finland with all three codes. The core state initial and boundary conditions prior to recriticality have been studied with the severe accident codes SCDAP/RELAP5, MELCOR and MAAP4. The results of the analyses show that all three codes predict recriticality - both superprompt power bursts and quasi steady-state power generation - for the studied range of parameters, i. e. with core uncovery and heat-up to maximum core temperatures around 1800 K and water flow rates of 45 kg/s to 2000 kg/s injected into the downcomer. Since the recriticality takes place in a small fraction of the core the power densities are high which results in large energy deposition in the fuel during power burst in some accident scenarios. The highest value, 418 cal/g, was obtained with SIMULATE-3K for an Oskarshamn 3 case with reflooding

  13. Instrumentation availability during severe accidents for a boiling water reactor with a Mark I containment

    International Nuclear Information System (INIS)

    In support of the US Nuclear Regulatory Commission Accident Management Research Program, the availability of instruments to supply accident management information during a broad range of severe accidents is evaluated for a Boiling Water Reactor with a Mark I containment. Results from this evaluation include: (1) the identification of plant conditions that would impact instrument performance and information needs during severe accidents; (2) the definition of envelopes of parameters that would be important in assessing the performance of plant instrumentation for a broad range of severe accident sequences; and (3) assessment of the availability of plant instrumentation during severe accidents

  14. Medical emergency provisions in case of large-scale radiation accidents (literature review)

    International Nuclear Information System (INIS)

    Problems of planning population protection in case of severe radiation accidents are considered. Attention is paid to the state of these problems in the USSR and other contries as well as to IAEA directives. The Three Mile Island and Chernobyl accidents are used for illustration purposes. Organization of medical help during radiation accidents, provided for in national regulations and experience gained during Chernobyl NPP accident are considered. Conclusion is made on the necessity of forcasting accident consequences with regard to local, social, economical, geographic and other conditions. Availability of medical provision plans, related to elimination of accident aftereffects and skill training, is obligatory

  15. Use of decision trees for evaluating severe accident management strategies in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Jae, Moosung [Hanyang Univ., Seoul (Korea, Republic of). Dept. of Nuclerar Engineering; Lee, Yongjin; Jerng, Dong Wook [Chung-Ang Univ., Seoul (Korea, Republic of). School of Energy Systems Engineering

    2016-07-15

    Accident management strategies are defined to innovative actions taken by plant operators to prevent core damage or to maintain the sound containment integrity. Such actions minimize the chance of offsite radioactive substance leaks that lead to and intensify core damage under power plant accident conditions. Accident management extends the concept of Defense in Depth against core meltdown accidents. In pressurized water reactors, emergency operating procedures are performed to extend the core cooling time. The effectiveness of Severe Accident Management Guidance (SAMG) became an important issue. Severe accident management strategies are evaluated with a methodology utilizing the decision tree technique.

  16. The management of accidents

    Directory of Open Access Journals (Sweden)

    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.

  17. Source term evaluation for accident conditions

    International Nuclear Information System (INIS)

    The Symposium presentations were divided into 5 sessions devoted to the following topics: in-vessel-release (12 papers), retention in the primary circuit (9 papers), ex-vessel release (6 papers), retention in containment (8 papers) and release from the plant (9 papers). In addition, a poster session was held (8 papers) as well as two panel discussions on the following subjects: containment challenges and regulatory implications. The Proceedings contain all the introductory summaries, papers and posters that were presented during the Symposium. A separate abstract was prepared for each of these papers

  18. The TMI-2 accident

    International Nuclear Information System (INIS)

    A critical study about the technical and man-related facts in order to establish what is considered the worst commercial nuclear power accident until 1986. Radiological consequences and stress to the public are considered in contrast to antinuclear groups. This descriptive and technical study has the purpose to document written and oral opinions obtained abroad and then explain to the public in an easy language terminology. Preliminary study describing safety related systems fails and the accident itself with minute to minute description, conduct to the consequences and then, to learned lessons

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  20. Lessons Learned from the Past Accidents for Safety Culture Development

    International Nuclear Information System (INIS)

    All nuclear organizations strive to sustain and improve safety. There is diversity in the way organizations understand the concept of safety and the actions that can help to drive improvements. This paper presents an overview of the lessons to be learned from past nuclear accidents and their relevance for the development of nuclear safety culture. Although the term Safety Culture emerged after the Chernobyl accident, the factors that contributed to earlier accidents, of which the most notable was the accident of Three Mile Island Unit 2 , are also relevant for nuclear safety culture. As regards the Fukushima accident from 2011, safety culture was once again brought into discussion. It is easier to manage the workplaces and the organizations than the minds of employees, as it is not possible to change the human condition, but changing the conditions under which people work. For this, the commitment of the top management is important, without which, it is not possible to make the necessary changes. (author)

  1. AP-1000 passive in-vessel retention design for a severe accident

    International Nuclear Information System (INIS)

    The AP-1000 is a Westinghouse two-loop 1100 MWe advanced pressurized water reactor (PWR) that uses passive safety features to enhance plant safety and to provide significant and measurable improvements in plant simplification, reliability, investment protection and plant costs. One of the passive safety features of the AP-1000 is In-Vessel Retention. In-Vessel Retention passively provides sufficient external cooling of the reactor vessel to retain a molten core inside the vessel in the unlikely event of a severe accident. This concept was proven by a series of tests and analyses, and offers numerous advantages over other severe accident core management designs. The testing that proved the In-Vessel Retention Concept for AP-1000 also identified a series of features and functions for the reactor vessel insulation, making it different from the reactor vessel insulation in any other nuclear power plant. This paper presents the key functional and interface requirements for the AP-1000 reactor vessel insulation and the design configuration that meets those requirements. Requirements are identified for both normal and severe accident conditions. The requirements for normal conditions are similar to those for any other reactor vessel insulation. The severe accident requirements include features that passively allow containment flood water in the reactor cavity to freely flow between the insulation and reactor vessel and other features that passively allow the resulting steam to freely vent. The AP-1000 reactor vessel insulation must also provide the appropriate annulus to optimally cool the reactor vessel and be structurally adequate to withstand the loads that occur during the severe accident and during certain pipe breaks in containment. (authors)

  2. Responding to the Fukushima Daiichi nuclear accident

    International Nuclear Information System (INIS)

    This article proposes a summary of the content of a report published by the OECD's NEA (Nuclear Energy Agency) in response to the Fukushima-Daiichi nuclear power plant accident. This report outlines international efforts to strengthen nuclear regulation, safety, research and radiological protection in the post-Fukushima context. It describes work on new reactors and legal frameworks, highlights key messages and lessons learnt, shared responsibilities, human and organisational factors, defence-in-depth, stakeholders engagement, crisis communication and emergency preparedness

  3. Development of Database for Accident Analysis in Indian Mines

    Science.gov (United States)

    Tripathy, Debi Prasad; Guru Raghavendra Reddy, K.

    2015-08-01

    Mining is a hazardous industry and high accident rates associated with underground mining is a cause of deep concern. Technological developments notwithstanding, rate of fatal accidents and reportable incidents have not shown corresponding levels of decline. This paper argues that adoption of appropriate safety standards by both mine management and the government may result in appreciable reduction in accident frequency. This can be achieved by using the technology in improving the working conditions, sensitising workers and managers about causes and prevention of accidents. Inputs required for a detailed analysis of an accident include information on location, time, type, cost of accident, victim, nature of injury, personal and environmental factors etc. Such information can be generated from data available in the standard coded accident report form. This paper presents a web based application for accident analysis in Indian mines during 2001-2013. An accident database (SafeStat) prototype based on Intranet of the TCP/IP agreement, as developed by the authors, is also discussed.

  4. AN IMPROVED MODEL FOR ESTIMATING RUNWAY ACCIDENT COST IN NIGERIA

    Directory of Open Access Journals (Sweden)

    Akinyemi Olasunkanmi Oriola

    2016-03-01

    Full Text Available This research proposes an improved model for estimating runway accident cost in the aviation industry in Nigeria. Bayesian Network was used to model the probability of consequences of runway accidents and subsequently the cost of the potential consequences. The Bayesian Network was also used to implement causal and diagnostic inference. Market interest rate which incorporates the effect of inflation was included to relax the assumption of constant economic value. The three classes of consequences of runway accidents identified in this study were fatal, serious, and minor. Domain experts were used to obtain relevant Bayesian causes and evidences related to the occurrence of consequence of runway accident. A mathematical equation was developed to solve the Bayesian Network influence diagram to obtain the probability of minor runway accident, serious runway accident and fatal runway accident as 0.7603, 0.1547 and 0.0850 respectively. Consequently, the estimated cost of runway accident (minor, serious and fatal was $23, 813.52, $20, 052.64 and $772, 856.06 respectively. The Bayesian Network diagnostic inference reveals the close relation of runway accidents in Nigeria aviation sector with aircraft system failure, approach/takeoff procedures, human factors, weather conditions and collision risk.

  5. Occupational accidents aboard merchant ships

    DEFF Research Database (Denmark)

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

    2002-01-01

    aboard. Relative risks for notified accidents and accidents causing permanent disability of 5% or more were calculated in a multivariate analysis including ship type, occupation, age, time on board, change of ship since last employment period, and nationality. Foreigners had a considerably lower recorded...... 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...... rate of accidents than Danish citizens. Age was a major risk factor for accidents causing permanent disability. Change of ship and the first period aboard a particular ship were identified as risk factors. Walking from one place to another aboard the ship caused serious accidents. The most serious...

  6. Occupational accidents: a perspective of pakistan construction industry

    International Nuclear Information System (INIS)

    It has been observed that the construction industry is one of the notorious industry having higher rate of facilities and injuries. Resulting in higher financial losses and work hour losses, which are normally faced by this industry due to occupational accidents. Construction industry has the highest occupational accidents rate recorded throughout the world after agriculture industry. The construction work site is often a busy place having an incredibly high account of activities taking place, where everyone is moving in frenzy having particular task assigned. In such an environment, occupational accidents do occur. This paper gives information about different types of occupational accidents and their causes in the construction industry of Pakistan. A survey has been carried out to identify the types of occupational accidents often occur at construction site. The impact of each occupational accident has also been identified. The input from the different stakeholders involved on the work site was analyzed using RIW (Relative Importance Weight) method. The findings of this research show that fall from elevation, electrocution from building power and snake bite are the frequent occupational accidents occur within the work site where as fall from elevation, struck by, snake bite and electrocution from faulty tool are the occupational accident with high impact within the construction industry of Pakistan. The results also shows the final ranking of the accidents based on higher frequency and higher impact. Poor Management, Human Element and Poor Site Condition are found as the root causes leading to such occupational accidents. Hence, this paper identify that what type of occupational accidents occur at the work place in construction industry of pakistan, in order to develop the corrective actions which should be adequate enough to prevent the re-occurrence of such accidents at work site. (author)

  7. Enhanced Accident Tolerant LWR Fuels: Metrics Development

    Energy Technology Data Exchange (ETDEWEB)

    Shannon Bragg-Sitton; Lori Braase; Rose Montgomery; Chris Stanek; Robert Montgomery; Lance Snead; Larry Ott; Mike Billone

    2013-09-01

    The Department of Energy (DOE) Fuel Cycle Research and Development (FCRD) Advanced Fuels Campaign (AFC) is conducting research and development on enhanced Accident Tolerant Fuels (ATF) for light water reactors (LWRs). This mission emphasizes the development of novel fuel and cladding concepts to replace the current zirconium alloy-uranium dioxide (UO2) fuel system. The overall mission of the ATF research is to develop advanced fuels/cladding with improved performance, reliability and safety characteristics during normal operations and accident conditions, while minimizing waste generation. The initial effort will focus on implementation in operating reactors or reactors with design certifications. To initiate the development of quantitative metrics for ATR, a LWR Enhanced Accident Tolerant Fuels Metrics Development Workshop was held in October 2012 in Germantown, MD. This paper summarizes the outcome of that workshop and the current status of metrics development for LWR ATF.

  8. Radiological consequences of the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The reactor accident at unit 4 of the Chernobyl nuclear power plant in Ukraine has deeply affected the living conditions of millions of people. Especially the health consequences have been of public concern up to the present and also been the subject of sometimes absurd claims. The current knowledge on the radiological consequences of the accident is reviewed. Though an increased hazard for some risk groups with high radiation exposure, e.g., liquidators, still cannot be totally excluded for the future, the majority of the population shows no statistically significant indication of radiation-induced illnesses. The contribution of the Research Center Juelich to the assessment of the post-accidental situation and psychological relief of the population is reported. The population groups still requiring special attention include, in particular, children growing up in highly contaminated regions and the liquidators of the years 1986 and 1987 deployed immediately after the accident. (author)

  9. Description of the accident

    International Nuclear Information System (INIS)

    The TMI-2 accident occurred in March 1979. The accident started with a simple and fairly common steam power plant failure--loss of feedwater to the steam generators. Because of a combination of design, training, regulatory policies, mechanical failures and human error, the accident progressed to the point where it eventually produced the worst known core damage in large nuclear power reactors. Core temperatures locally reached UO2 fuel liquefaction (metallic solution with Zr) and even fuel melt (3800-51000F). Extensive fission product release and Zircaloy cladding oxidation and embrittlement occurred. At least the upper 1/2 of the core fractured and crumbled upon quenching. The lower central portion of the core apparently had a delayed heatup and then portions of it collapsed into the reactor vessel lower head. The lower outer portion of the core may be relatively undamaged. Outside of the core boundary, only those steel components directly above and adjacent to the core (≤1 foot) are known to have suffered significant damage (localized oxidation and melting). Other portions of the primary system outside of the reactor vessel apparently had little chance of damage or even notable overheating. The demonstrated coolability of the severely damaged TMI-2 core, once adequate water injection began, was one of the most substantial and important results of the TMI-2 accident

  10. The Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The documentation abstracted contains a complete survey of the broadcasts transmitted by the Russian wire service of the Deutsche Welle radio station between April 28 and Mai 15, 1986 on the occasion of the Chernobyl reactor accident. Access is given to extracts of the remarkable eastern and western echoes on the broadcasts of the Deutsche Welle. (HP)

  11. Measures against nuclear accidents

    International Nuclear Information System (INIS)

    A select committee appointed by the Norwegian Ministry of Social Affairs put forward proposals concerning measures for the improvement of radiation protection preparedness in Norway. On the basis on an assessment of the potential radiation accident threat, the report examines the process of response, and identifies the organizational and management factors that influence that process

  12. Road Traffic Accidents in Kazakhstan

    OpenAIRE

    Alma Aubakirova; Alibek Kossumov; Nurbek Igissinov

    2013-01-01

    Background: The article provides the analysis of death rates in road traffic accidents in Kazakhstan from 2004 to 2010 and explores the use of sanitary aviation. Methods: Data of fatalities caused by road traffic accidents were collected and analysed. Descriptive and analytical methods of epidemiology and biomedical statistics were applied. Results: Totaly 27,003 people died as a result of road traffic accidents in this period. The death rate for the total population due to road traffic accid...

  13. The psychology of nuclear accidents

    International Nuclear Information System (INIS)

    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. (U.K.)

  14. Authority structure and industrial accidents

    NARCIS (Netherlands)

    As, Sicco van

    2001-01-01

    This paper deals with the influence of organizational characteristics on safety. Accidents are actually caused by individual mistakes. However the underlying causes of accidents are often organizational. The general hypothesis is that the authority structure is a main cause of accident-proneness wit

  15. A Study on the Operation Strategy for Combined Accident including TLOFW accident

    International Nuclear Information System (INIS)

    It is difficult for operators to recognize the necessity of a feed-and-bleed (F-B) operation when the loss of coolant accident and failure of secondary side occur. An F-B operation directly cools down the reactor coolant system (RCS) using the primary cooling system when residual heat removal by the secondary cooling system is not available. The plant is not always necessary the F-B operation when the secondary side is failed. It is not necessary to initiate an F-B operation in the case of a medium or large break because these cases correspond to low RCS pressure sequences when the secondary side is failed. If the break size is too small to sufficiently decrease the RCS pressure, the F-B operation is necessary. Therefore, in the case of a combined accident including a secondary cooling system failure, the provision of clear information will play a critical role in the operators' decision to initiate an F-B operation. This study focuses on the how we establish the operation strategy for combined accident including the failure of secondary side in consideration of plant and operating conditions. Previous studies have usually focused on accidents involving a TLOFW accident. The plant conditions to make the operators confused seriously are usually the combined accident because the ORP only focuses on a single accident and FRP is less familiar with operators. The relationship between CET and PCT under various plant conditions is important to decide the limitation of initiating the F-B operation to prevent core damage

  16. A Study on the Operation Strategy for Combined Accident including TLOFW accident

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bo Gyung; Kang, Gook Young [KAIST, Daejeon (Korea, Republic of); Yoon, Ho Joon [Khalifa University, Abu Dhabi (United Arab Emirates)

    2014-10-15

    It is difficult for operators to recognize the necessity of a feed-and-bleed (F-B) operation when the loss of coolant accident and failure of secondary side occur. An F-B operation directly cools down the reactor coolant system (RCS) using the primary cooling system when residual heat removal by the secondary cooling system is not available. The plant is not always necessary the F-B operation when the secondary side is failed. It is not necessary to initiate an F-B operation in the case of a medium or large break because these cases correspond to low RCS pressure sequences when the secondary side is failed. If the break size is too small to sufficiently decrease the RCS pressure, the F-B operation is necessary. Therefore, in the case of a combined accident including a secondary cooling system failure, the provision of clear information will play a critical role in the operators' decision to initiate an F-B operation. This study focuses on the how we establish the operation strategy for combined accident including the failure of secondary side in consideration of plant and operating conditions. Previous studies have usually focused on accidents involving a TLOFW accident. The plant conditions to make the operators confused seriously are usually the combined accident because the ORP only focuses on a single accident and FRP is less familiar with operators. The relationship between CET and PCT under various plant conditions is important to decide the limitation of initiating the F-B operation to prevent core damage.

  17. The spatial distribution of workplace accidents in Spain: assessing the role of workplace inspections

    OpenAIRE

    Bande, Roberto; López-Mourelo, Elva

    2014-01-01

    This paper analyses the spatial distribution of workplace accidents in Spain and analyses the role of economic and institutional variables in this geographical outcome. After estimating an econometric model that explains regional variation in job accidents incidence, we compute conditional regional distributions of workplace accidents under the assumption of no regional variation in workplace inspections. Results show that much of the regional differences in severe and fatal accidents are exp...

  18. Benchmarking Severe Accident Computer Codes for Heavy Water Reactor Applications

    International Nuclear Information System (INIS)

    Requests for severe accident investigations and assurance of mitigation measures have increased for operating nuclear power plants and the design of advanced nuclear power plants. Severe accident analysis investigations necessitate the analysis of the very complex physical phenomena that occur sequentially during various stages of accident progression. Computer codes are essential tools for understanding how the reactor and its containment might respond under severe accident conditions. The IAEA organizes coordinated research projects (CRPs) to facilitate technology development through international collaboration among Member States. The CRP on Benchmarking Severe Accident Computer Codes for HWR Applications was planned on the advice and with the support of the IAEA Nuclear Energy Department's Technical Working Group on Advanced Technologies for HWRs (the TWG-HWR). This publication summarizes the results from the CRP participants. The CRP promoted international collaboration among Member States to improve the phenomenological understanding of severe core damage accidents and the capability to analyse them. The CRP scope included the identification and selection of a severe accident sequence, selection of appropriate geometrical and boundary conditions, conduct of benchmark analyses, comparison of the results of all code outputs, evaluation of the capabilities of computer codes to predict important severe accident phenomena, and the proposal of necessary code improvements and/or new experiments to reduce uncertainties. Seven institutes from five countries with HWRs participated in this CRP

  19. Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendix XI. Analysis of comments on the draft WASH-1400 report. [PWR and BWR

    Energy Technology Data Exchange (ETDEWEB)

    1975-10-01

    Information is presented concerning comments on reactor safety by governmental agencies and civilian organizations; reactor safety study methodology; consequence model; probability of accident sequences; and various accident conditions.

  20. Tractor accidents in Swedish traffic.

    Science.gov (United States)

    Pinzke, Stefan; Nilsson, Kerstin; Lundqvist, Peter

    2012-01-01

    The objective of this study is to reach a better understanding of accidents on Swedish roads involving tractors and to suggest ways of preventing them. In an earlier study we analyzed police-reported fatal accidents and accidents that led to physical injuries from 1992 to 2005. During each year of this period, tractors were involved in 128 traffic accidents on average, an average of 7 people were killed, 44 sustained serious injuries, and 143 sustained slight injuries. The number of fatalities in these tractor accidents was about 1.3% of all deaths in traffic accidents in Sweden. Cars were most often involved in the tractor accidents (58%) and 15% were single vehicle accidents. The mean age of the tractor driver involved was 39.8 years and young drivers (15-24 years) were overrepresented (30%). We are now increasing the data collected with the years 2006-2010 in order to study the changes in the number of accidents. Special attention will be given to the younger drivers and to single vehicle accidents. Based on the results we aim to develop suggestions for reducing road accidents, e.g. including measures for making farm vehicles more visible and improvement of the training provided at driving schools. PMID:22317543

  1. The size-dependent charge fraction of sub-3-nm particles as a key diagnostic of competitive nucleation mechanisms under atmospheric conditions

    Science.gov (United States)

    Yu, F.; Turco, R. P.

    2011-09-01

    A clear physical understanding of atmospheric particle nucleation mechanisms is critical in assessing the influences of aerosols on climate and climate variability. Currently, several mechanisms have been proposed and are being employed to interpret field observations of nucleation events. Roughly speaking, the two most likely candidates are neutral cluster nucleation (NCN) and ion-mediated nucleation (IMN). Detailed nucleation event data has been obtained in boreal forests. In one set of analyses of these measurements, NCN was suggested as the dominant formation mode, while in another, it was IMN. Information on the electrical charge distribution carried by the nucleating clusters is one key for identifying the relative contributions of neutral and ion-mediated processes under various conditions. Fortunately, ground-breaking measurements of the charged states or fractions of ambient nanometer-sized particles soon after undergoing nucleation are now available to help resolve the main pathways. In the present study, the size-dependent "apparent" formation rates and fractions of charged and neutral particles in a boreal forest setting are simulated with a detailed kinetic model. We show that the predicted "apparent" formation rates of charged and neutral particles at 2 nm for eight representative case study days agree well with the corresponding values based on observations. In the simulations, the "apparent" contribution of ion-based nucleation increases by up to ~one order of magnitude as the size of "sampled" particles is decreased from 2 nm to ~1.5 nm. These results suggest that most of the neutral particles sampled in the field at sizes around 2 nm are in reality initially formed on ionic cores that are neutralized before the particles grow to this size. Thus, although the apparent rate of formation of neutral 2-nm particles might seem to be dominated by a neutral clustering process, in fact those particles may be largely the result of an ion-induced nucleation

  2. The Key Indicator Method for Manual Handling Operations (KIM-MHO - evaluation of a new method for the assessment of working conditions within a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Gebhardt Hansjürgen

    2010-11-01

    Full Text Available Abstract Background Upper extremity musculoskeletal symptoms and disorders are common in the working population. The economic and social impact of such disorders is considerable. Long-time, dynamic repetitive exposure of the hand-arm system during manual handling operations (MHO alone or in combination with static and postural effort are recognised as causes of musculoskeletal symptoms and disorders. The assessment of these manual work tasks is crucial to estimate health risks of exposed employees. For these work tasks, a new method for the assessment of the working conditions was developed by the Federal Institute for Occupational Safety and Health (BAuA and released as a draft in the year 2007. The draft of the so-called Key Indicator Method for Manual Handling Operations (KIM-MHO was developed in analogy with the existing KIM for Lifting/Holding/Carrying (KIM-LHC and Pulling/Pushing (KIM-PP of loads. The KIM-MHO is designed to fill the gap existing in risk assessment of manual work processes, since the existing KIMs deal only with manual handling of loads. This research project focused on the following: - Examination of the validity of workplace assessment with the KIM-MHO comparing expert ratings with the results of the observations. - Examination of the objectivity of workplace assessment with the KIM-MHO applied by different examiners. - Examination of the criterion validity of the risk assessment provided by KIM-MHO with respect to the association between exposure and the occurrence and prevalence of health related outcomes. Methods/Design To determine the objectivity and validity of workplace assessment, the KIM-MHO is applied by occupational health and safety officers at different workplaces involving manual handling operations. To determine the criterion validity of risk assessment, a survey of employees at different workplaces takes place with standardised questionnaires and interviews about symptoms in the neck and upper extremities

  3. [Drowning accidents in childhood].

    Science.gov (United States)

    Krandick, G; Mantel, K

    1990-09-30

    This is a report on five boys aged between 1 and 5 years who, after prolonged submersion in cold water, were treated at our department. On being taken out of the water, all the patients were clinically dead. After 1- to 3-hour successful cardiopulmonary resuscitation, with a rectal temperature of about 27 degrees C, they were rewarmed at a rate of 1 degree/hour. Two patients died within a few hours after the accident. One patient survived with an apallic syndrome, 2 children survived with no sequelae. In the event of a water-related accident associated with hypothermia, we consider suitable resuscitation to have preference over rewarming measures. The most important treatment guidelines and prognostic factors are discussed.

  4. Nuclear ship accidents

    International Nuclear Information System (INIS)

    In this report available information on 28 nuclear ship accident and incidents is considered. Of these 5 deals with U.S. ships and 23 with USSR ships. The ships are in almost all cases nuclear submarines. Only events that involve the nuclear propulsion plants, radiation exposures, fires/explosions and sea water leaks into the submarines are considered. Comments are made on each of the events, and at the end of the report an attempt is made to point out the weaknesses of the submarine designs which have resulted in the accidents. It is emphasized that much of the available information is of a rather dubious nature. consequently some of the assessments made may not be correct. (au)

  5. Farm accidents in children.

    Science.gov (United States)

    Cogbill, T H; Busch, H M; Stiers, G R

    1985-10-01

    During a 6 1/2 year period, 105 children were admitted to the hospital as the result of trauma that occurred on farms. The mechanism of injury was animal related in 42 (40%), tractor or wagon accident in 28 (26%), farm machinery in 21 (20%), fall from farm building in six (6%), and miscellaneous in eight (8%). Injury Severity Score was calculated for each patient. An Injury Severity Score of greater than or equal to 25 was determined for 11 children (11%). Life-threatening injuries, therefore, are frequently the result of childhood activities that take place in agricultural environments. The most common injuries were orthopedic, neurologic, thoracoabdominal, and maxillofacial. There was one death in the series, and only one survivor sustained major long-term disability. Such injuries are managed with optimal outcome in a regional trauma center. Educational programs with an emphasis on prevention and safety measures may reduce the incidence of farm accidents. PMID:4047799

  6. Dementia and Traffic Accidents

    DEFF Research Database (Denmark)

    Petersen, Jindong Ding; Siersma, Volkert; Nielsen, Connie Thurøe;

    2016-01-01

    BACKGROUND: As a consequence of a rapid growth of an ageing population, more people with dementia are expected on the roads. Little is known about whether these people are at increased risk of road traffic-related accidents. OBJECTIVE: Our study aims to investigate the risk of road traffic......-related accidents for people aged 65 years or older with a diagnosis of dementia in Denmark. METHODS: We will conduct a nationwide population-based cohort study consisting of Danish people aged 65 or older living in Denmark as of January 1, 2008. The cohort is followed for 7 years (2008-2014). Individual's personal...... data are available in Danish registers and can be linked using a unique personal identification number. A person is identified with dementia if the person meets at least one of the following criteria: (1) a diagnosis of the disease in the Danish National Patient Register or in the Danish Psychiatric...

  7. Fukushima Accident: Was it preventable or unavoidable? - A sociological perspective

    International Nuclear Information System (INIS)

    Global renaissance of nuclear energy was widely predicted and accepted before the Fukushima accident of March 11, 2011. The prospects for nuclear energy now appear to face a turn-around point. Serious debates about the adequacy of nuclear power utilization and safety regulation are underway in many national and/or international settings. Many investigations and analyses have been and will be conducted to identify the causes and consequences and to seek lessons to be taken into account in their own nuclear power programs. These efforts evidently will contribute to preventing accidents caused by such extreme damage conditions as Fukushima desperately encountered. But, in order to discuss the future of nuclear energy, new approach to the nature of the accident needs to be sought rather than the usual and conventional way of viewing the accidents with the benefit of hindsight. This paper examines institutional and sociological aspects of Fukushima accident to get some clues as to whether it was preventable or unavoidable

  8. ACTIVITIES OF THE ADMINISTRATION OF FEDERAL SERVICE FOR SURVEILLANCE ON CONSUMER RIGHTS PROTECTION AND HUMAN WELL-BEING IN KHABAROVSKY KRAI IN CONDITIONS OF THE FUKUSHIMA ACCIDENT AND MEASURES UNDERTAKEN TO PROTECT THE TERRITORY AND POPULATION THE REGION

    Directory of Open Access Journals (Sweden)

    V. A. Ott

    2011-01-01

    Full Text Available The article analyzes activities of the Administration of Federal Service for Surveillance on Consumer Rights Protection and Human Well-being in Khabarovsky Krai and the Federal Health Organization "Center of Hygiene and Epidemiology in Khabarovsky Krai" in the situation related to the Fukushima accident in Japan

  9. Severe Accident Test Station Design Document

    Energy Technology Data Exchange (ETDEWEB)

    Snead, Mary A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yan, Yong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howell, Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Keiser, James R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Terrani, Kurt A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    The purpose of the ORNL severe accident test station (SATS) is to provide a platform for evaluation of advanced fuels under projected beyond design basis accident (BDBA) conditions. The SATS delivers the capability to map the behavior of advanced fuels concepts under accident scenarios across various temperature and pressure profiles, steam and steam-hydrogen gas mixtures, and thermal shock. The overall facility will include parallel capabilities for examination of fuels and irradiated materials (in-cell) and non-irradiated materials (out-of-cell) at BDBA conditions as well as design basis accident (DBA) or loss of coolant accident (LOCA) conditions. Also, a supporting analytical infrastructure to provide the data-needs for the fuel-modeling components of the Fuel Cycle Research and Development (FCRD) program will be put in place in a parallel manner. This design report contains the information for the first, second and third phases of design and construction of the SATS. The first phase consisted of the design and construction of an out-of-cell BDBA module intended for examination of non-irradiated materials. The second phase of this work was to construct the BDBA in-cell module to test irradiated fuels and materials as well as the module for DBA (i.e. LOCA) testing out-of-cell, The third phase was to build the in-cell DBA module. The details of the design constraints and requirements for the in-cell facility have been closely captured during the deployment of the out-of-cell SATS modules to ensure effective future implementation of the in-cell modules.

  10. 49 CFR 835.11 - Obtaining Board accident reports, factual accident reports, and supporting information.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Obtaining Board accident reports, factual accident... Board accident reports, factual accident reports, and supporting information. It is the responsibility... obtain Board accident reports, factual accident reports, and accompanying accident docket files....

  11. Time analysis of fatal traffic accidents in Fars Province of Iran

    Directory of Open Access Journals (Sweden)

    Heydari Seyed Taghi

    2013-04-01

    Full Text Available 【Abstract】 Objective: To analyze the time factor in road traffic accidents (RTAs in Fars Province of Iran. Methods: This study was conducted in Fars Province, Iran from November 22, 2009 to November 21, 2011. Victims’ information consisted of age, sex, death toll involving dri-vers or passengers of cars, motorcycles and pedestrians, and site of injury etc. Accidents were analyzed in relation to hour of the day, season of the year, lighting condition in-cluding sunrise, sunset, daytime and nighttime. Results: A total of 3 642 deaths (78.3% were males, and the ratio of males to females was about 3.6:1 were studied regarding their autopsy records. There was a steady in-crease in fatal accidents occurring at midnight to 15:59. The risk of being involved in a fatal traffic accident was higher for those injured between 4:00 to 7:59 than at other times (OR=2.13, 95% CI 1.85-2.44. The greatest number of fatal RTAs took place in summer. Mortalities due to RTA during spring and summer were more pronounced at 20:00 to 23:59 and midnight to 3:59, whereas mortalities in fall and winter were more pronounced from 12:00 to 15:59. Conclusion: The high mortality rate of RTA is a major public health problem in Fars Province. Our results indicate that the time is an important factor which contributes to road traffic deaths. Key words: Accidents, traffic; Epidemiology; Mortality; Iran

  12. ASSESSMENT OF RUNWAY ACCIDENT HAZARDS IN NIGERIA AVIATION SECTOR

    Directory of Open Access Journals (Sweden)

    Akinyemi Olasunkanmi Oriola

    2015-06-01

    Full Text Available Aviation crashes all over the world have recently been on the high rise, stemming from negligence, mechanical faults, weather, ground control errors, pilot errors, taxing and maintenance crew errors as probable reasons for such accidents. This study models the probabilistic risk assessment of runway accident hazards in Nigeria aviation sector. Six categories of runway accident hazards with their corresponding basic events were identified and modeled using fault tree analysis method of probabilistic risk assessment. The six categories of runway accident hazards are runway surface conditions, weather conditions, collision risk, aircraft system failure, approach/takeoff procedures and human factors. The Fault Tree developed is a system of OR-gates and the weights for each hazard were derived through a domain/expert opinion. The estimated probability of occurrence of runway accident which is the top event of the Fault Tree model is 0.2624. Fault Tree Analysis; thus, identifies the most likely root causes of runway accident through importance measures. The results of the analysis show close relationship of runway accidents in Nigeria aviation sector with aircraft system failure, approach/takeoff procedures, human factor, weather conditions and collision risk.

  13. Development Process of Plant-specific Severe Accident Management Guidelines for Wolsong Nuclear Power Plants

    International Nuclear Information System (INIS)

    A severe accident, which occurred at the TMI in 1979 and Chernobyl in 1986, is an accident that exceeds design basis accidents and leads to significant core damage. The severe accident is the low possibility of occurrence but the high severity. To mitigate the consequences of the severe accidents, Korean Nuclear Safety Committee declared the Severe Accident Policy in 2001, which requested the development of Severe Accident Management Guidelines (SAMGs) for operating plants. SAMG is a symptom-based guidance that takes a set of actions to alleviate the outcomes of severe accidents and to get into the safe stable plant condition. The purpose of this paper is to presents the strategic development process of the PHWR SAMG. The guidelines consist of 5 categories: an emergency guide for the main control room (MCR) operators, a strategy implementing guide for the technical support center (TSC), six mitigation guides, a monitoring guide, and a termination guide

  14. A study on PHWR moderator and severe accident analysis system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Tae; Rhee, B. W.; Kim, D. H. [KAERI, Daejeon (Korea, Republic of); and others

    2012-04-15

    For the purpose of establishment of PHWR moderator and severe accident analysis system, the following works are performed. The main thermal-hydraulic phenomena are investigated and scaling analysis of the scaled down test facility design and fabrication are done to determine the scaling ratio based on the scaling law and practical constraints of the test facility. Theoretical background of the commercial CFD codes has been found out and their applicability and application conditions for the moderator circulation analysis are reviewed to develop the computer code requirement for the moderator 3-D analysis codes. Satisfactory analysis results against the STERN Lab. experiment showed the applicability of OpenFOAM and CUPID codes to moderator circulation analysis. For the development of various accident scenarios for establishing the DB for severe accident phenomena/progression, the level 1 and the level 2 PSA analysis results for Wolsong Unit 1 are reviewed and the most probable accident scenarios from the PDS event trees are selected. The latest ISAAC 4.03 version is used to predict the basic accident progression and the improvement items for the most up-to-date severe accident analysis issues analyzing function are derived. A basic system for the PHWR severe accident management decision making support system, SAMEX-CR is set up and requirement for the DB management system, SARDB-CR is derived to develop the implementation methodology for severe accident analysis DB management system.

  15. The study of core melting phenomena in reactor severe accident of PWR

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hong; Jeun, Gyoo Dong; Park, Seh In; Lim, Jae Hyuck; Park, Seong Yong [Hanyang Univ., Seoul (Korea, Republic of); Bang, Kwang Hyun; Kim, Ki Yong [Korea Maritime Univ., Busan (Korea, Republic of)

    1999-03-15

    After TMI-2 accident, it has been paid much attention to severe accidents beyond the design basis accidents and the research on the progress of severe accidents and mitigation and the closure of severe accidents has been actively performed. In particular, a great deal of uncertainties yet exist in the phase of late core melt progression and thus the research on this phase of severe accident progress has a key role in obtaining confidence in severe accident mitigation and nuclear reactor safety. In the present study, physics of late core melt progression, experimental data and the major phenomenological models of computer codes are reviewed and a direction of reducing the uncertainties in the late core melt progression is proposed.

  16. Radiation accident/disaster

    International Nuclear Information System (INIS)

    Described are the course of medical measures following Fukushima Daiichi Nuclear Power Plant (FNPP) Accident after the quake and tsunami (Mar. 11, 2011) and the future task for radiation accident/disaster. By the first hydrogen explosion in FNPP (Mar. 12), evacuation of residents within 20 km zone was instructed, and the primary base for measures of nuclear disaster (Off-site Center) 5 km afar from FNPP had to work as a front base because of damage of communicating ways, of saving of injured persons and of elevation of dose. On Mar. 13, the medical arrangement council consisting from stuff of Fukushima Medical University (FMU), National Institute of Radiological Sciences, Nuclear Safety Research Association and Prefectural officers was setup in residents' hall of Fukushima City, and worked for correspondence to persons injured or exposed, where communication about radiation and between related organizations was still poor. The Off-site Center's head section moved to Prefectural Office on Mar. 15 as headquarters. Early in the period, all residents evacuated from the 20 km zone, and in-hospital patients and nursed elderly were transported with vehicles, >50 persons of whom reportedly died mainly by their base diseases. The nation system of medicare for emergent exposure had consisted from the network of the primary to third facilities; there were 5 facilities in the Prefecture, 3 of which were localized at 4-9 km distance from FNPP and closed early after the Accident; and the secondary facility of FMU became responsible to all exposed persons. There was no death of workers of FNPP. Medical stuff also measured the ambient dose at various places near FNPP, having had risk of exposure. At the Accident, the important system of command, control and communication was found fragile and measures hereafter should be planned on assumption of the worst scenario of complete damage of the infrastructure and communication. It is desirable for Disaster Medical Assistance Team which

  17. Systematic register of nuclear accidents

    International Nuclear Information System (INIS)

    The Systematic Register of Nuclear Accidents is a consolidation of important accidents occurred in the world during the period 1945-1984. Important accidents can be defined as those involving high radiation doses, which require the exposed individuals to undergo medical treatment. The organization and structuring of this register rests on the necessity for the availability of a database specifically oriented to researchers interested in studying the different nuclear accidents reported. Approximately 150 accidents in that period are presented in a summary form; these accidents had been described or reported in the scientific literature or made known through informal communications of Brazilian and foreign institutions and researchers. This register can be of interest particularly to all professionals who either directly of indirectly work in the area of nuclear or radioactive installations safety. In order to facilitate analysis by the researcher, that casuistic system was divided into 3 groups: criticality accidents (table I), fall-out on Marshall Islands (table II) and external irradiation accidents (table III). It is also included an overview of accidents in that period, indicating the total number of victims, fatal cases, and number of survivors. The author offers to the reader an extensive bibliography on the accidents described. (Author)

  18. Accidents caused by electric currents; Unfaelle durch elektrischen Strom

    Energy Technology Data Exchange (ETDEWEB)

    Juehling, J. [Berufsgenossenschaft der Feinmechanik und Elektrotechnik, Koeln (Germany). Inst. zur Erforschung Elektrischer Unfaelle

    1998-12-31

    The present evaluation only refers to accidents caused by electric currents in member companies of the employees` industrial compensation society of the fine mechanics and electrical engineering professions (BGFE). In some cases the institute also publishes statistics on the frequency time course of electrical accidents which deviate from those the relevant annual report. This is mainly due to the fact that these statistics also contain non-notifiable accidents communicated via medical reports and the supplementary report on electrical accidents. They further contain keyed data on electrical accidents reported by other employees` industrial compensation societies. Inquiries made to the institute may therefore be answered on the basis of all the above-mentioned data on electrical accidents as well as on the overall accident statistics of the BGFE. [Deutsch] Die nachfolgenden Auswertungen beziehen sich nur auf Unfaelle in Mitgliedsbetrieben der BG F und E, verursacht durch den elektrischen Strom. Zum Teil veroeffentlicht aber das Institut Zahlen ueber die zeitliche Entwicklung von Stromunfaellen, die nicht immer mit den Angaben der jeweiligen Jahresberichte uebereinstimmen muessen. Das liegt vor allem daran, dass auch nicht-meldepflichtige Unfaelle ueber den D-Arztbericht und ueber den Ergaenzungsbericht bei Unfaellen durch elektrischen Strom - also ueber aerztliche Erhebungsformulare - erfasst werden. Ausserdem werden auch von anderen Berufsgenossenschaften eingehende Stromunfaelle verschluesselt. Zur Beantwortung von Anfragen an das Institut koennen also all die vorgenannten Daten zu elektrischen Unfaellen und natuerlich auch die Zahlen zum Gesamtunfallgeschehen der BG F und E herangezogen werden. (orig.)

  19. Development of Parameter Network for Accident Management Applications

    Energy Technology Data Exchange (ETDEWEB)

    Pak, Sukyoung; Ahemd, Rizwan; Heo, Gyunyoung [Kyung Hee Univ., Yongin (Korea, Republic of); Kim, Jung Taek; Park, Soo Yong; Ahn, Kwang Il [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    When a severe accident happens, it is hard to obtain the necessary information to understand of internal status because of the failure or damage of instrumentation and control systems. We learned the lessons from Fukushima accident that internal instrumentation system should be secured and must have ability to react in serious conditions. While there might be a number of methods to reinforce the integrity of instrumentation systems, we focused on the use of redundant behavior of plant parameters without additional hardware installation. Specifically, the objective of this study is to estimate the replaced value which is able to identify internal status by using set of available signals when it is impossible to use instrumentation information in a severe accident, which is the continuation of the paper which was submitted at the last KNS meeting. The concept of the VPN was suggested to improve the quality of parameters particularly to be logged during severe accidents in NPPs using a software based approach, and quantize the importance of each parameter for further maintenance. In the future, we will continue to perform the same analysis to other accident scenarios and extend the spectrum of initial conditions so that we are able to get more sets of VPNs and ANN models to predict the behavior of accident scenarios. The suggested method has the uncertainty underlain in the analysis code for severe accidents. However, In case of failure to the safety critical instrumentation, the information from the VPN would be available to carry out safety management operation.

  20. JCO criticality accident as POST-LOCA: Poor structure induced loss of organizational control accident

    International Nuclear Information System (INIS)

    Some problems in operation and business management of JCO (Japan Nuclear Fuel Conversion Co.) have been studied as background factors of the criticality accident. Open information about business conditions of JCO suggests that the cause of the accident is not so simple as to be attributed only to economic pressure, but includes immanent problems in JCO. We investigate the problems from five viewpoints, organization of safety management, system of operation management, activities for business improvement, risk awareness, and restructuring of business, and discuss the effects and causality of background factors as well as remedies for them. (author)

  1. Development of the severe accident risk information database management system SARD

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Kwang Il; Kim, Dong Ha

    2003-01-01

    The main purpose of this report is to introduce essential features and functions of a severe accident risk information management system, SARD (Severe Accident Risk Database Management System) version 1.0, which has been developed in Korea Atomic Energy Research Institute, and database management and data retrieval procedures through the system. The present database management system has powerful capabilities that can store automatically and manage systematically the plant-specific severe accident analysis results for core damage sequences leading to severe accidents, and search intelligently the related severe accident risk information. For that purpose, the present database system mainly takes into account the plant-specific severe accident sequences obtained from the Level 2 Probabilistic Safety Assessments (PSAs), base case analysis results for various severe accident sequences (such as code responses and summary for key-event timings), and related sensitivity analysis results for key input parameters/models employed in the severe accident codes. Accordingly, the present database system can be effectively applied in supporting the Level 2 PSA of similar plants, for fast prediction and intelligent retrieval of the required severe accident risk information for the specific plant whose information was previously stored in the database system, and development of plant-specific severe accident management strategies.

  2. Development of the severe accident risk information database management system SARD

    International Nuclear Information System (INIS)

    The main purpose of this report is to introduce essential features and functions of a severe accident risk information management system, SARD (Severe Accident Risk Database Management System) version 1.0, which has been developed in Korea Atomic Energy Research Institute, and database management and data retrieval procedures through the system. The present database management system has powerful capabilities that can store automatically and manage systematically the plant-specific severe accident analysis results for core damage sequences leading to severe accidents, and search intelligently the related severe accident risk information. For that purpose, the present database system mainly takes into account the plant-specific severe accident sequences obtained from the Level 2 Probabilistic Safety Assessments (PSAs), base case analysis results for various severe accident sequences (such as code responses and summary for key-event timings), and related sensitivity analysis results for key input parameters/models employed in the severe accident codes. Accordingly, the present database system can be effectively applied in supporting the Level 2 PSA of similar plants, for fast prediction and intelligent retrieval of the required severe accident risk information for the specific plant whose information was previously stored in the database system, and development of plant-specific severe accident management strategies

  3. Accident management insights after the Fukushima Daiichi NPP accident

    International Nuclear Information System (INIS)

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

  4. Authority structure and industrial accidents

    OpenAIRE

    As, Sicco van

    2001-01-01

    This paper deals with the influence of organizational characteristics on safety. Accidents are actually caused by individual mistakes. However the underlying causes of accidents are often organizational. The general hypothesis is that the authority structure is a main cause of accident-proneness within organizations. On one side, the most obvious model for a safe organization would be the ideal-typical bureaucracy. On the other side, potential problems are little flexibility and control is ba...

  5. Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Following the accident at Chernobyl nuclear reactor, WHO organized on 6 May 1986 in Copenhagen a one day consultation of experts with knowledge in the fields of meteorology, radiation protection, biological effects, reactor technology, emergency procedures, public health and psychology in order to analyse the development of events and their consequences and to provide guidance as to the needs for immediate public health action. The present report provides detailed information on the transportation and dispersion of the radioactive material in the atmosphere, especially volatile elements, during the release period 26 April - 5 May. Presented are the calculated directions and locations of the radioactive plume over Europe in the first 5 days after the accident, submitted by the Swedish Meteorological and Hydrological Institute. The calculations have been made for two heights, 1500m and 750m and the plume directions are grouped into five periods, covering five European areas. The consequences of the accident inside the USSR and the radiological consequences outside the USSR are presented including the exposure routes and the biological effects, paying particular attention to iodine-131 effects. Summarized are the first reported measured exposure rates above background, iodine-131 deposition and concentrations in milk and the remedial actions taken in various European countries. Concerning the cesium-137 problem, based on the UNSCEAR assessment of the consequences of the nuclear fallout, one concludes that the cesium contamination outside the USSR is not likely to cause any serious problems. Finally, the conclusions and the recommendations of the meeting, taking into account both the short-term and longer term considerations are presented

  6. Comparative Assessment Of Natural Gas Accident Risks

    Energy Technology Data Exchange (ETDEWEB)

    Burgherr, P.; Hirschberg, S

    2005-01-01

    The study utilizes a hierarchical approach including (1) comparative analyses of different energy chains, (2) specific evaluations for the natural gas chain, and (3) a detailed overview of the German situation, based on an extensive data set provided by Deutsche Vereinigung des Gas- und Wasserfaches (DVGW). According to SVGW-expertise DVGW-data can be regarded as fully representative for Swiss conditions due to very similar technologies, management, regulations and safety culture, but has a substantially stronger statistical basis because the German gas grid is about 30 times larger compared to Switzerland. Specifically, the following tasks were carried out by PSI to accomplish the objectives of this project: (1) Consolidation of existing ENSAD data, (2) identification and evaluation of additional sources, (3) comparative assessment of accident risks, and (4) detailed evaluations of specific issues and technical aspects for severe and smaller accidents in the natural gas chain that are relevant under Swiss conditions. (author)

  7. 中国百万千瓦级核电站严重事故下堆芯损伤评价%Core Damage Assessment for Chinese 1 000 MWe NPP Under Severe Accident Conditions

    Institute of Scientific and Technical Information of China (English)

    魏玮; 周志伟

    2011-01-01

    By simulation analysis with the integral severe accident analysis code MELCOR1.8.5, the applicability of the Westinghouse Owners Group Core Damage Assessment Guidance (CDAG) to estimate the status and extent of the core damage in the early phase of the accident for a typical Chinese 1 000 MWe NPP was investigated. The preliminary analysis results show that CDAG can reasonably evaluate the core damage status and extent for the 1 000 MWe NPP in a loss of coolant accident (LOCA) without mitigation measures. The insights gained from the present study are of significant values for further studing and validating the comprehensive assessment capability and applicability of the CDAG, and for advancing the establishment of the severe accident management guidelines (SAMGs) of existing plants in China.%应用-体化严重事故分析程序MELCORL 8.5进行模拟分析,研究了由西屋公司制定、经美国NRC(Nuclear Regulatory Commission)认证的"堆芯损伤评价导则(CDAG )"应用于中国百万千瓦级核电站在严重事故初期评价堆芯损伤状态和程度的有效性.初步分析结果表明,CDAG可较好地评价百万千瓦级核电站无缓解措施的冷却剂丧失事故(LOCA)堆芯损伤状况和损伤程度,对进-步研究和验证CDAG的综合评价能力和适用性、推进现有核电厂建立严重事故管理导则具有重要的参考价值.

  8. The accident of Chernobyl

    International Nuclear Information System (INIS)

    RBMK reactors (reactor control, protection systems, containment) and the nuclear power plant of Chernobyl are first presented. The scenario of the accident is given with a detailed chronology. The actions and consequences on the site are reviewed. This report then give the results of the source term estimation (fision product release, core inventory, trajectories, meteorological data...), the radioactivity measurements obtained in France. Health consequences for the French population are evoked. The medical consequences for the population who have received a high level of doses are reviewed

  9. Serious accident in Peru

    International Nuclear Information System (INIS)

    A peruvian man, victim of an important accidental irradiation arrived on the Saturday twenty ninth of may 1999 to the centre of treatment of serious burns at the Percy military hospital (Clamart -France). The accident spent on the twentieth of February 1999, on the site of a hydroelectric power plant, in construction at 300 km at the East of Lima. The victim has picked up an industrial source of iridium devoted to gamma-graphy operations and put it in his back pocket; of trousers. The workman has serious radiation burns. (N.C.)

  10. Accident prevention programme

    International Nuclear Information System (INIS)

    This study by the Steel Industry Safety and Health Commission was made within the context of the application by undertakings of the principles of accident and disease prevention previously adopted by the said Commission. It puts forward recommendations for the effective and gradual implementation of a programme of action on occupational health and safety in the various departments of an undertaking and in the undertaking as a whole. The methods proposed in this study are likely to be of interest to all undertakings in the metallurgical industry and other industrial sectors

  11. Guidance on accidents involving radioactivity

    International Nuclear Information System (INIS)

    This annex contains advice to Health Authorities on their response to accidents involving radioactivity. The guidance is in six parts:-(1) planning the response required to nuclear accidents overseas, (2) planning the response required to UK nuclear accidents a) emergency plans for nuclear installations b) nuclear powered satellites, (3) the handling of casualties contaminated with radioactive substances, (4) background information for dealing with queries from the public in the event of an accident, (5) the national arrangements for incident involving radioactivity (NAIR), (6) administrative arrangements. (author)

  12. The expert assistant in accident management

    International Nuclear Information System (INIS)

    In the event of a nuclear accident in proximity to an urban area, the consequences resulting from the complex processes of environmental transport of radioactivity would require complex countermeasures. Emphasis has been placed on either modelling the potential effects of such an event on the population, or on attempting to predict the geographical evolution of the release. Less emphasis has been placed on the development of accident management aids with a in-built data acquisition capability. Given the problems of predicting the evolution of an accidental release of activity, more emphasis should be placed on the development of small regional systems specifically engineered to acquire and display environmental data in the most efficaceous form possible. A wealth of information can be obtained from appropriately-sited outstations which can aid those responsible for countermeasures in their decision making processes. The substantial volume of data which would arrive within the duration and during the aftermath of an accident requires skilled interpretation under conditions of considerable stress. It is necessary that a management aid notonly presents these data in a rapidly assimilable form, but is capable of making intelligent decisions of its own, on such matters as information display priority and the polling frequency of outstations. The requirement is for an expert assistant. The XERSES accident management aid has been designed with the foregoing features in mind. Intended for covering regions up to approximately 100 kms square, it links with between 1 and 64 outstations supplying a variety of environmental data. Under quiescent conditions the system will operate unattended, raising alarms remotely only when detecting abnormal conditions. Under emergency conditions, the system automatically adjusts such operating parameters as data acquisition rate

  13. Spent fuel shipping cask accident evaluation

    International Nuclear Information System (INIS)

    Mathematical models have been developed to simulate the dynamic behavior, following a hypothetical accident and fire, of typical casks designed for the rail shipment of spent fuel from nuclear reactors, and to determine the extent of radioactive releases under postulated conditions. The casks modeled were the IF-300, designed by the General Electric Company for the shipment of spent LWR fuel, and a cask designed by the Aerojet Manufacturing Company for the shipment of spent LMFBR fuel

  14. 1976 Hanford americium accident

    Energy Technology Data Exchange (ETDEWEB)

    Heid, K R; Breitenstein, B D; Palmer, H E; McMurray, B J; Wald, N

    1979-01-01

    This report presents the 2.5-year medical course of a 64-year-old Hanford nuclear chemical operator who was involved in an accident in an americium recovery facility in August 1976. He was heavily externally contaminated with americium, sustained a substantial internal deposition of this isotope, and was burned with concentrated nitric acid and injured by flying debris about the face and neck. The medical care given the patient, including the decontamination efforts and clinical laboratory studies, are discussed. In-vivo measurements were used to estimate the dose rates and the accumulated doses to body organs. Urinary and fecal excreta were collected and analyzed for americium content. Interpretation of these data was complicated by the fact that the intake resulted both from inhalation and from solubilization of the americium embedded in facial tissues. A total of 1100 ..mu..Ci was excreted in urine and feces during the first 2 years following the accident. The long-term use of diethylenetriaminepentate (DTPA), used principally as the zinc salt, is discussed including the method, route of administration, and effectiveness. To date, the patient has apparently experienced no complications attributable to this extensive course of therapy, even though he has been given approximately 560 grams of DTPA. 4 figures, 1 table.

  15. Lessons of the Chernobyl Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Insensitivity of radiation without measuring apparatus and health outcome observed in the atomic bomb survivors of Hiroshima and Nagasaki are major sources that make people fear the possible late effects of radiation exposure attributable to nuclear power plant accident. However, the health conditions of people in the last 20 years around Chernobyl indicated the necessity to review the risk assessment suggesting that effects of radiation exposure may considerably be different between the atomic bombing and nuclear power plant accident. (author)

  16. Planning the medical response to radiological accidents

    International Nuclear Information System (INIS)

    Radioactive substances and other sources of ionizing radiation are used to assist in diagnosing and treating diseases, improving agricultural yields, producing electricity and expanding scientific knowledge. The application of sources of radiation is growing daily, and consequently the need to plan for radiological accidents is growing. While the risk of such accidents cannot be entirely eliminated, experience shows that most of the rare cases that have occurred could have been prevented, as they are often caused by human error. Recent radiological accidents such as those at Chernobyl (Ukraine 1986), Goiania (Brazil 1987), San Salvador (El Salvador 1989), Sor-Van (Israel 1990), Hanoi (Viet Nam 1992) and Tammiku (Estonia 1994) have demonstrated the importance of adequate preparation for dealing with such emergencies. Medical preparedness for radiological accidents must be considered an integral part of general emergency planning and preparedness and established within the national framework for radiation protection and safety. An IAEA Technical Committee meeting held in Istanbul in 1988 produced some initial guidance on the subject, which was subsequently developed, reviewed and updated by groups of consultants in 1989, 1992 and 1996. Special comments were provided by WHO, as co-sponsor of this publication, in 1997. This Safety Report outlines the roles and tasks of health authorities and hospital administrators in emergency preparedness for radiological accidents. Health authorities may use this document as the basis for their medical management in a radiological emergency, bearing in mind that adaptations will almost certainly be necessary to take into account the local conditions. This publication also provides information relevant to the integration of medical preparedness into emergency plans

  17. Explaining the road accident risk: weather effects.

    Science.gov (United States)

    Bergel-Hayat, Ruth; Debbarh, Mohammed; Antoniou, Constantinos; Yannis, George

    2013-11-01

    This research aims to highlight the link between weather conditions and road accident risk at an aggregate level and on a monthly basis, in order to improve road safety monitoring at a national level. It is based on some case studies carried out in Work Package 7 on "Data analysis and synthesis" of the EU-FP6 project "SafetyNet-Building the European Road Safety Observatory", which illustrate the use of weather variables for analysing changes in the number of road injury accidents. Time series analysis models with explanatory variables that measure the weather quantitatively were used and applied to aggregate datasets of injury accidents for France, the Netherlands and the Athens region, over periods of more than 20 years. The main results reveal significant correlations on a monthly basis between weather variables and the aggregate number of injury accidents, but the magnitude and even the sign of these correlations vary according to the type of road (motorways, rural roads or urban roads). Moreover, in the case of the interurban network in France, it appears that the rainfall effect is mainly direct on motorways--exposure being unchanged, and partly indirect on main roads--as a result of changes in exposure. Additional results obtained on a daily basis for the Athens region indicate that capturing the within-the-month variability of the weather variables and including it in a monthly model highlights the effects of extreme weather. Such findings are consistent with previous results obtained for France using a similar approach, with the exception of the negative correlation between precipitation and the number of injury accidents found for the Athens region, which is further investigated. The outlook for the approach and its added value are discussed in the conclusion. PMID:23928504

  18. 叶片断裂事故条件下直驱式风电机组动态特性分析%Dynamic Characteristics Analyzed of Large Scale Directly-driven Wind Turbines under Blade Fracture Accident Condition

    Institute of Scientific and Technical Information of China (English)

    戴巨川

    2013-01-01

    以兆瓦级直驱式风电机组为研究对象,进行叶片断裂事故发生后风电机组动态特性分析.通过将风轮载荷模型、机电耦合模型和变桨距控制等多个风电机组子系统模型进行集成,得到较完整的系统整体模型.在风轮载荷模型中,不但考虑气动载荷,也考虑惯性载荷和重力载荷等;变桨距控制充分考虑变桨距机构动力学特性.在Simulink环境下建立风电机组数值仿真模型,并假定叶片断裂后几秒内风电机组尚未停机进行仿真研究.研究结果发现,一个叶片断裂后,风轮旋转力矩出现突变,发电机电磁力矩快速响应风轮机械旋转力矩,风轮转速能控制在设定值附近波动;风电机组能量捕获与转换出现失衡,变流器直流电压、输入电网有功功率和无功功率等都出现大幅度波动,造成对电网的冲击.通过分析叶片断裂后风电机组动态特性,能够为风电机组结构设计、运行控制等提供有益的参考.%Million watt scale directly-driven wind turbines are chosen as the study object and its dynamic characteristics are analyzed at the condition of a blade fracture accident happening. By integrating the wind rotor loads sub-model, electromechanical coupling sub-model and pitch control sub-model, the system models of wind turbines are obtained. In the wind rotor loads sub-model, not only the aerodynamic force but also the inertia force and gravity force are considered; in the pitch actuator sub-model, the dynamic characteristics are considered. According to the established wind turbine models, the corresponding numerical simulation models are constructed in Simulink; the simulation is carried out assuming that wind turbines have yet to be stopped after a few seconds of blade fracture. The research results show that when a blade fracture happening, the wind rotor mechanical rotational torque mutates. Since the generator electromagnetic torque tracks quickly the wind rotor

  19. Containment building hydrogen control methods related to degraded core accidents

    International Nuclear Information System (INIS)

    Degraded core accident-related release of hydrogen under some circumstances may threaten the integrity of pressurized water reactor containment buildings. This report provides a preliminary survey of a spectrum of possible approaches which could be adopted to maintain containment building integrity under accident conditions which lead to the release of hydrogen. Particular attention is directed to large, dry containment of the Zion and Indian Point designs. For any such possible accident, there exists a sequence of time intervals characterizing the accident scenario. This report considers the generic features of these intervals and discusses the suitability of various approaches to hydrogen accident control as related to the characteristics of the interval during which they are applied. It was found that various options exist for hydrogen control strategies and that their usefulness depends on the particular accident scenarios to be considered. Of all the hydrogen control approaches considered, a strategy of continuous inerting of the containment building is the only one which clearly eliminates the combustion hazard, does not involve adverse environmental effects, and succeeds in a way that is independent of the accident scenario

  20. The Fukushima accident: radiological consequences and first lessons. Proceedings

    International Nuclear Information System (INIS)

    This document brings together the available presentations given at the conference organised by the French society of radiation protection about the Fukushima accident, its radiological consequences and the first lessons learnt. Sixteen presentations (slides) are compiled in this document and deal with: 1 - Accident progress and first actions (Thierry Charles, IRSN); 2 - Conditions and health monitoring of the Japanese intervention teams (Bernard Le Guen, EDF); 3 - The Intra Group action after the Fukushima accident (Michel Chevallier, Groupe Intra; Frederic Mariotte, CEA); 4 - Processing of effluents (Georges Pagis, Areva); 5 - Fukushima accident: impact on the terrestrial environment in Japan (Didier Champion, IRSN); 6 - Consequences of the Fukushima accident on the marine environment (Dominique Boust, IRSN); 7 - Territories decontamination perspectives (Pierre Chagvardieff, CEA); 8 - Actions undertaken by Japanese authorities (Florence Gallay, ASN); 9 - Japanese population monitoring and health stakes (Philippe Pirard, InVS); 10 - Citizen oversight actions implemented in Japan (David Boilley, ACRO); 11 - Implementation of ICRP's (International Commission on Radiological Protection) recommendations by Japanese authorities: first analysis (Jacques Lochard, CIPR); 12 - Control of Japan imported food stuff (David Brouque, DGAL); 13 - Questions asked by populations in France and in Germany (Florence-Nathalie Sentuc, GRS; Pascale Monti, IRSN); 14 - Labour law applicable to French workers working abroad (Thierry Lahaye, DGT); 15 - Protection of French workers working in Japan, Areva's experience (Patrick Devin, Areva); 16 - Fukushima accident experience feedback and post-accident nuclear doctrine (Jean-Luc Godet, ASN)

  1. Health Problems in Radiation Accidents

    International Nuclear Information System (INIS)

    The authors define a radiation accident as a situation which has led or could have led to the unexpected irradiation of persons or contamination of the environment over and above the levels accepted as safe. Several categories of accidents are distinguished as a function of the consequences to be expected. The suggested system of classifying accidents makes it possible to plan post-accident measures within a single system of 'concentric circles', taking into account at the same time whether it will be possible to carry out the post-accident measures unaided or whether it will be necessary to bring in additional manpower and resources from outside. The authors consider the possibility of countering the effects of accidents as a function of their nature, with reference to the biological, economic and psychological aspects. They evaluate the part played by the health service in planning and carrying out accident prevention measures, and consider the function of radiological units attached to epidemiological health stations ; these units are essentially centres providing for precautionary measures to avert accidents and action to counter their effects. (author)

  2. Preventing accidents at intake towers

    Energy Technology Data Exchange (ETDEWEB)

    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)

  3. Probability of spent fuel transportation accidents

    Energy Technology Data Exchange (ETDEWEB)

    McClure, J. D.

    1981-07-01

    The transported volume of spent fuel, incident/accident experience and accident environment probabilities were reviewed in order to provide an estimate of spent fuel accident probabilities. In particular, the accident review assessed the accident experience for large casks of the type that could transport spent (irradiated) nuclear fuel. This review determined that since 1971, the beginning of official US Department of Transportation record keeping for accidents/incidents, there has been one spent fuel transportation accident. This information, coupled with estimated annual shipping volumes for spent fuel, indicated an estimated annual probability of a spent fuel transport accident of 5 x 10/sup -7/ spent fuel accidents per mile. This is consistent with ordinary truck accident rates. A comparison of accident environments and regulatory test environments suggests that the probability of truck accidents exceeding regulatory test for impact is approximately 10/sup -9//mile.

  4. Analyse des conditions de travail des travailleurs intérimaires Analysis of the Working Conditions of Temporary Workers. Explaining These Workers’ Vulnerability to Occupational Accidents Análisis de las condiciones de trabajo de los trabajadores temporales. Cómo explicar la vulnerabilidad de estos trabajadores a los accidentes laborales ?

    Directory of Open Access Journals (Sweden)

    Rachid Belkacem

    2012-11-01

    Full Text Available Cet article analyse les conditions de travail des intérimaires. Il s’appuie sur les résultats d’une étude réalisée en 2008/2009 et financée par la Direction régionale du travail, de l’emploi et de la formation professionnelle – région Lorraine. Cette recherche a été organisée autour de deux travaux de terrain : une enquête par questionnaires et des entretiens semi-directifs menés auprès d’intérimaires détachés dans l’industrie et/ou le BTP. Cet article montre que la vulnérabilité des intérimaires aux accidents du travail est forte comparativement aux salariés permanents des entreprises. Cette dernière s’explique par des conditions de travail relativement plus difficiles. Ces travailleurs doivent s’adapter très souvent dans l’urgence à des contextes de travail différents et évolutifs.This paper analyzes the main characteristics of the working conditions of temporary workers in France. It examines the data from a large study conducted in 2008/2009 and financed by the Regional Labor Department of Lorraine (DRTEFP- Lorraine. Our research was organized around two surveys involving temporary workers in industry and/or construction and civil engineering. This article shows that temporary employees’ vulnerability to occupational accidents is higher than that of companies’ permanent employees. This vulnerability can be explained by relatively more difficult working conditions. Quite often, these workers must quickly adapt to different and evolving work contexts.Este artículo analiza las condiciones de trabajo de los trabajadores temporales en Francia. El mismo se apoya en los resultados de un estudio realizado en 2008/2009, financiado por la Dirección Regional del Trabajo, Empleo y Formación Profesional –Región Lorraine. Esta investigación ha sido organizada sobre la base de dos trabajos de terreno : encuesta y entrevistas a trabajadores temporales vinculados a la industria y/o al BTP. Este art

  5. Sleep apnea and occupational accidents: Are oral appliances the solution?

    Directory of Open Access Journals (Sweden)

    Maria De Lourdes Rabelo Guimarães

    2014-01-01

    Full Text Available Background: Dental practitioners have a key role in the quality of life and prevention of occupational accidents of workers with Obstructive Sleep Apnea Syndrome (OSAS. Aim: The aim of this study was to review the impact of OSAS, the Continuous Positive Airway Pressure (CPAP therapy, and the evidence regarding the use of oral appliances (OA on the health and safety of workers. Materials and Methods: Searches were conducted in MEDLINE (PubMed, Lilacs and Sci ELO. Articles published from January 1980 to June 2014 were included. Results: The research retrieved 2188 articles and 99 met the inclusion criteria. An increase in occupational accidents due to reduced vigilance and attention in snorers and patients with OSAS was observed. Such involvements were related to excessive daytime sleepiness and neurocognitive function impairments. The use of OA are less effective when compared with CPAP, but the results related to excessive sleepiness and cognitive performance showed improvements similar to CPAP. Treatments with OA showed greater patient compliance than the CPAP therapy. Conclusion: OSAS is a prevalent disorder among workers, leads to increased risk of occupational accidents, and has a significant impact on the economy. The CPAP therapy reduces the risk of occupational accidents. The OA can improve the work performance; but there is no scientific evidence associating its use with occupational accidents reduction. Future research should focus on determining the cost-effectiveness of OA as well as its influence and efficacy in preventing occupational accidents.

  6. Evaluation Metrics Applied to Accident Tolerant Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Shannon M. Bragg-Sitton; Jon Carmack; Frank Goldner

    2014-10-01

    The safe, reliable, and economic operation of the nation’s nuclear power reactor fleet has always been a top priority for the United States’ nuclear industry. Continual improvement of technology, including advanced materials and nuclear fuels, remains central to the industry’s success. Decades of research combined with continual operation have produced steady advancements in technology and have yielded an extensive base of data, experience, and knowledge on light water reactor (LWR) fuel performance under both normal and accident conditions. One of the current missions of the U.S. Department of Energy’s (DOE) Office of Nuclear Energy (NE) is to develop nuclear fuels and claddings with enhanced accident tolerance for use in the current fleet of commercial LWRs or in reactor concepts with design certifications (GEN-III+). Accident tolerance became a focus within advanced LWR research upon direction from Congress following the 2011 Great East Japan Earthquake, resulting tsunami, and subsequent damage to the Fukushima Daiichi nuclear power plant complex. The overall goal of ATF development is to identify alternative fuel system technologies to further enhance the safety, competitiveness and economics of commercial nuclear power. Enhanced accident tolerant fuels would endure loss of active cooling in the reactor core for a considerably longer period of time than the current fuel system while maintaining or improving performance during normal operations. The U.S. DOE is supporting multiple teams to investigate a number of technologies that may improve fuel system response and behavior in accident conditions, with team leadership provided by DOE national laboratories, universities, and the nuclear industry. Concepts under consideration offer both evolutionary and revolutionary changes to the current nuclear fuel system. Mature concepts will be tested in the Advanced Test Reactor at Idaho National Laboratory beginning in Summer 2014 with additional concepts being

  7. Evaluation Metrics Applied to Accident Tolerant Fuels

    International Nuclear Information System (INIS)

    The safe, reliable, and economic operation of the nation’s nuclear power reactor fleet has always been a top priority for the United States’ nuclear industry. Continual improvement of technology, including advanced materials and nuclear fuels, remains central to the industry’s success. Decades of research combined with continual operation have produced steady advancements in technology and have yielded an extensive base of data, experience, and knowledge on light water reactor (LWR) fuel performance under both normal and accident conditions. One of the current missions of the US. Department of Energy’s (DOE) Office of Nuclear Energy (NE) is to develop nuclear fuels and claddings with enhanced accident tolerance characteristics for use in the current fleet of commercial LWRs or in reactor concepts with design certifications (GEN-III+). LWR fuel with accident tolerant characteristics became a focus within advanced LWR research following the 2011 Great East Japan Earthquake, resulting tsunami, and subsequent damage to the Fukushima Daiichi nuclear power plant complex, and upon receiving direction from Congress. The overall goal of ATF development is to identify alternative fuel system technologies to further enhance the safety, competitiveness and economics of commercial nuclear power. Enhanced accident tolerant fuels would endure loss of active cooling in the reactor core for a considerably longer period of time than the current fuel system while maintaining or improving performance during normal operations. The US. DOE is supporting multiple teams to investigate a number of technologies that may improve fuel system response and behaviour in accident conditions, with team leadership provided by DOE national laboratories, universities, and the nuclear industry. Concepts under consideration offer both evolutionary and revolutionary changes to the current nuclear fuel system. Mature concepts will be tested in the Advanced Test Reactor at Idaho National

  8. Improvement of Severe Accident Analysis Computer Code and Development of Accident Management Guidance for Heavy Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soo Yong; Kim, Ko Ryu; Kim, Dong Ha; Kim, See Darl; Song, Yong Mann; Choi, Young; Jin, Young Ho

    2005-03-15

    The objective of the project is to develop a generic severe accident management guidance(SAMG) applicable to Korean PHWR and the objective of this 3 year continued phase is to construct a base of the generic SAMG. Another objective is to improve a domestic computer code, ISAAC (Integrated Severe Accident Analysis code for CANDU), which still has many deficiencies to be improved in order to apply for the SAMG development. The scope and contents performed in this Phase-2 are as follows: The characteristics of major design and operation for the domestic Wolsong NPP are analyzed from the severe accident aspects. On the basis, preliminary strategies for SAM of PHWR are selected. The information needed for SAM and the methods to get that information are analyzed. Both the individual strategies applicable for accident mitigation under PHWR severe accident conditions and the technical background for those strategies are developed. A new version of ISAAC 2.0 has been developed after analyzing and modifying the existing models of ISAAC 1.0. The general SAMG applicable for PHWRs confirms severe accident management techniques for emergencies, provides the base technique to develop the plant specific SAMG by utility company and finally contributes to the public safety enhancement as a NPP safety assuring step. The ISAAC code will be used inevitably for the PSA, living PSA, severe accident analysis, SAM program development and operator training in PHWR.

  9. Artificial intelligence applications in accident management

    International Nuclear Information System (INIS)

    For nuclear power plant accident management, there are some addition concerns: linking AI systems to live data streams must be mastered; techniques for processing sensor inputs with varying data quality need to be provided; systems responsiveness to changing plant conditions and multiple user requests should, in general, be improved; there is a need for porting applications from specialized AI machines onto conventional computer hardware without incurring unacceptable performance penalties; human factors guidelines are required for new user interfaces in AI applications; methods for verification and validation of AI-based systems must be developed; and, finally, there is a need for proven methods to evaluate use effectiveness and firmly establish the benefits of AI-based accident management systems. (orig./GL)

  10. A framework for assessing severe accident management strategies

    International Nuclear Information System (INIS)

    Accident management can be defined as the innovative use of existing and or alternative resources, systems and actions to prevent or mitigate a severe accident. Together with risk management (changes in plant operation and/or addition of equipment) and emergency planning (off-site actions), accident management provides an extension of the defense-in-depth safety philosophy for severe accidents. A significant number of probabilistic safety assessments (PSA) have been completed which yield the principal plant vulnerabilities. For each sequence/threat and each combination of strategy there may be several options available to the operator. Each strategy/option involves phenomenological and operational considerations regarding uncertainty. These considerations include uncertainty in key phenomena, uncertainty in operator behavior, uncertainty in system availability and behavior, and uncertainty in available information (i.e., instrumentation). The objective of this project is to develop a methodology for assessing severe accident management strategies given the key uncertainties mentioned above. Based on Decision Trees and Influence Diagrams, the methodology is currently being applied to two case studies: cavity flooding in a PWR to prevent vessel penetration or failure, and drywell flooding in a BWR to prevent containment failure

  11. An analysis of accident data for franchised public buses in Hong Kong.

    Science.gov (United States)

    Evans, W A; Courtney, A J

    1985-10-01

    This paper analyses data on accidents involving franchised public buses operating in Hong Kong. The data were obtained from the Royal Hong Kong Police, the Hong Kong Government Transport Department, the two major franchised bus operators and international sources. The analysis includes an international comparison of accidents with emphasis on the situation in Hong Kong compared to urban areas in the United Kingdom. An attempt has been made to identify the characteristics of bus accidents; accident incidence has been related to time of day, day of the week, time of year, weather conditions, driver's age and experience, hours on duty and policy-reported cause. The results indicate that Hong Kong has a high accident rate compared to Japan, the U.K. and the U.S.A., with particularly high pedestrian involvement rates. Bus accidents peak at around 9:00 AM and 4:00 PM but the accident rate is high throughout the day. Monday and Saturday appear to have a higher than average accident rate. The variability of accident rate throughout the year does not seem to be significant and the accident rate does not appear to be influenced by weather conditions. Older, more experienced drivers generally have a safer driving record than their younger, less experienced colleagues. Accident occurrence is related to the time the driver has been on duty. The paper questions the reliability of police-reported accident causation data and suggests improvements in the design of the accident report form and in the training of police investigators. The relevance of the Hong Kong study for accident research in general is also discussed. PMID:4096796

  12. Recent Developments in Level 2 PSA and Severe Accident Management

    International Nuclear Information System (INIS)

    In 1997, CSNI WGRISK produced a report on the state of the art in Level 2 PSA and severe accident management - NEA/CSNI/R(1997)11. Since then, there have been significant developments in that more Level 2 PSAs have been carried out worldwide for a variety of nuclear power plant designs including some that were not addressed in the original report. In addition, there is now a better understanding of the severe accident phenomena that can occur following core damage and the way that they should be modelled in the PSA. As requested by CSNI in December 2005, the objective of this study was to produce a report that updates the original report and gives an account of the developments that have taken place since 1997. The aim has been to capture the most significant new developments that have occurred rather than to provide a full update of the original report, most of which is still valid. This report is organised using the same structure as the original report as follows: Chapter 2: Summary on state of application, results and insights from recent Level 2 PSAs. Chapter 3: Discussion on key severe accident phenomena and modelling issues, identification of severe accident issues that should be treated in Level 2 PSAs for accident management applications, review of severe accident computer codes and the use of these codes in Level 2 PSAs. Chapter 4: Review of approaches and practices for accident management and SAM, evaluation of actions in Level 2 PSAs. Chapter 5: Review of available Level 2 PSA methodologies, including accident progression event tree / containment event tree development. Chapter 6: Aspects important to quantification, including the use of expert judgement and treatment of uncertainties. Chapter 7: Examples of the use of the results and insights from the Level 2 PSA in the context of an integrated (risk informed) decision making process

  13. EPIDEMIOGY OF TRAFFIC ACCIDENTS IN TEHRAN 1.EVENT: THE ACCIDENTS

    Directory of Open Access Journals (Sweden)

    K Nasseri

    1977-11-01

    Full Text Available A total of 38, 300 traffic collisions have occurred in Tehran, the capital of Iran, during 1973. 5, 655 of these collisions in 6, 700 injuries and 560 deaths are selected and discussed. There has been no difference between the accident rates in working and holidays. Winter has had the lowest rate, and accidents have been in direct relationship with the crowdedness and heavy traffic periods. Ninety – eight per cent of the accidents have been caused by either the drivers or the pedestrians’ negligence. These and other findings are discussed.

  14. Economic development, mobility and traffic accidents in Algeria.

    Science.gov (United States)

    Bougueroua, M; Carnis, L

    2016-07-01

    The aim of this contribution is to estimate the impact of road economic conditions and mobility on traffic accidents for the case of Algeria. Using the cointegration approach and vector error correction model (VECM), we will examine simultaneously short term and long-term impacts between the number of traffic accidents, fuel consumption and gross domestic product (GDP) per capital, over the period 1970-2013. The main results of the estimation show that the number of traffic accidents in Algeria is positively influenced by the GDP per capita in the short and long term. It implies that a higher economic development worsens the road safety situation. However, the new traffic rules adopted in 2009 have an impact on the forecast trend of traffic accidents, meaning efficient public policy could improve the situation. This result calls for a strong political commitment with effective countermeasures for avoiding the further deterioration of road safety record in Algeria. PMID:27070081

  15. Applying Functional Modeling for Accident Management of Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lind, Morten; Zhang Xinxin [Harbin Engineering University, Harbin (China)

    2014-08-15

    The paper investigate applications of functional modeling for accident management in complex industrial plant with special reference to nuclear power production. Main applications for information sharing among decision makers and decision support are identified. An overview of Multilevel Flow Modeling is given and a detailed presentation of the foundational means-end concepts is presented and the conditions for proper use in modelling accidents are identified. It is shown that Multilevel Flow Modeling can be used for modelling and reasoning about design basis accidents. Its possible role for information sharing and decision support in accidents beyond design basis is also indicated. A modelling example demonstrating the application of Multilevel Flow Modelling and reasoning for a PWR LOCA is presented.

  16. A database system for the management of severe accident risk information, SARD

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, K. I.; Kim, D. H. [KAERI, Taejon (Korea, Republic of)

    2003-10-01

    The purpose of this paper is to introduce main features and functions of a PC Windows-based database management system, SARD, which has been developed at Korea Atomic Energy Research Institute for automatic management and search of the severe accident risk information. Main functions of the present database system are implemented by three closely related, but distinctive modules: (1) fixing of an initial environment for data storage and retrieval, (2) automatic loading and management of accident information, and (3) automatic search and retrieval of accident information. For this, the present database system manipulates various form of the plant-specific severe accident risk information, such as dominant severe accident sequences identified from the plant-specific Level 2 Probabilistic Safety Assessment (PSA) and accident sequence-specific information obtained from the representative severe accident codes (e.g., base case and sensitivity analysis results, and summary for key plant responses). The present database system makes it possible to implement fast prediction and intelligent retrieval of the required severe accident risk information for various accident sequences, and in turn it can be used for the support of the Level 2 PSA of similar plants and for the development of plant-specific severe accident management strategies.

  17. Factors contributing to young moped rider accidents in Denmark

    DEFF Research Database (Denmark)

    Møller, Mette; Haustein, Sonja

    2016-01-01

    Young road users still constitute a high-risk group with regard to road traffic accidents. The crash rate of a moped is four times greater than that of a motorcycle, and the likelihood of being injured in a road traffic accident is 10-20 times higher among moped riders compared to car drivers. Ne...... and awareness of mopeds among other road users. Due to their young age the effect of such measures could be enhanced by infrastructural measures facilitating safe interaction between mopeds and other road users.......Young road users still constitute a high-risk group with regard to road traffic accidents. The crash rate of a moped is four times greater than that of a motorcycle, and the likelihood of being injured in a road traffic accident is 10-20 times higher among moped riders compared to car drivers...... was made between accident factors related to (1) the road and its surroundings, (2) the vehicle, and (3) the reported behaviour and condition of the road user. Thirteen accident factors were identified with the majority concerning the reported behaviour and condition of the road user. The average number...

  18. Passive depressurization accident management strategy for boiling water reactors

    International Nuclear Information System (INIS)

    Highlights: • We proposed two passive depressurization systems for BWR severe accident management. • Sensitivity analysis of the passive depressurization systems with different leakage area. • Passive depressurization strategies can prevent direct containment heating. - Abstract: According to the current severe accident management guidance, operators are required to depressurize the reactor coolant system to prevent or mitigate the effects of direct containment heating using the safety/relief valves. During the course of a severe accident, the pressure boundary might fail prematurely, resulting in a rapid depressurization of the reactor cooling system before the startup of SRV operation. In this study, we demonstrated that a passive depressurization system could be used as a severe accident management tool under the severe accident conditions to depressurize the reactor coolant system and to prevent an additional devastating sequence of events and direct containment heating. The sensitivity analysis performed with SAMPSON code also demonstrated that the passive depressurization system with an optimized leakage area and failure condition is more efficient in managing a severe accident

  19. Working condition: A key factor in increasing occupational hazard among bidi rollers: A population health research with respect to DNA damage

    Directory of Open Access Journals (Sweden)

    Poonam Shukla

    2011-01-01

    Full Text Available The present investigation was undertaken to study the role of working conditions in occupational hazards among bidi rollers occupationally exposed to tobacco dust with reference to DNA damage in peripheral blood lymphocytes. Initially, biomonitoring was conducted by estimating urinary thioether to detect the extent of xenobiotic exposure, and genotoxicity was evaluated by assessing DNA damage and micronucleus frequency in buccal epithelial cells in female bidi rollers occupationally exposed to bidi tobacco dust. Student′s t-test was used to test the significance between the means. Results showed a significant increase in urinary thioether level in during-shift urine samples as compared to pre-shift samples, which indicated exposure of bidi rollers to xenobiotic compounds. A significant increase in DNA damage was observed in the rollers working in confined environment as compared to those who worked in open and mixed kind of working conditions. Keeping in view the adverse effects of tobacco inhalation on the genotoxic effects in bidi rollers as an occupational hazard and in order to minimize the hazardous effects, it is recommended that masks should be worn by the bidi rollers during work to minimize inhalation of tobacco dust. Gloves should be worn particularly if there are bruises etc. in the palm. To minimize the absorption through eyes, covered glasses should be worn. The entire process of bidi rolling may be done preferably under well ventilated conditions. Due care to be taken to sit in the direction facing the direction of wind to avoid inhalation of blown away tobacco dust.

  20. International aspects of nuclear accidents

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  2. Regulatory impact of nuclear reactor accident source term assumptions. Technical report

    International Nuclear Information System (INIS)

    This report addresses the reactor accident source term implications on accident evaluations, regulations and regulatory requirements, engineered safety features, emergency planning, probabilistic risk assessment, and licensing practice. Assessment of the impact of source term modifications and evaluation of the effects in Design Basis Accident analyses, assuming a change of the chemical form of iodine from elemental to cesium iodide, has been provided. Engineered safety features used in current LWR designs are found to be effective for all postulated combinations of iodine source terms under DBA conditions. In terms of potential accident consequences, it is not expected that the difference in chemical form between elemental iodine and cesium iodide would be significant. In order to account for the current information on source terms, a spectrum of accident scenerios is discussed to realistically estimate the source terms resulting from a range of potential accident conditions

  3. Preliminary analysis of loss-of-coolant accident in Fukushima nuclear accident

    Science.gov (United States)

    Su'ud, Zaki; Anshari, Rio

    2012-06-01

    Loss-of-Coolant Accident (LOCA) in Boiling Water Reactor (BWR) especially on Fukushima Nuclear Accident will be discussed in this paper. The Tohoku earthquake triggered the shutdown of nuclear power reactors at Fukushima Nuclear Power station. Though shutdown process has been completely performed, cooling process, at much smaller level than in normal operation, is needed to remove decay heat from the reactor core until the reactor reach cold-shutdown condition. If LOCA happen at this condition, it will cause the increase of reactor fuel and other core temperatures and can lead to reactor core meltdown and exposure of radioactive material to the environment such as in the Fukushima Dai Ichi nuclear accident case. In this study numerical simulation has been performed to calculate pressure composition, water level and temperature distribution on reactor during this accident. There are two coolant regulating system that operational on reactor unit 1 at this accident, Isolation Condensers (IC) system and Safety Relief Valves (SRV) system. Average mass flow of steam to the IC system in this event is 10 kg/s and could keep reactor core from uncovered about 3,2 hours and fully uncovered in 4,7 hours later. There are two coolant regulating system at operational on reactor unit 2, Reactor Core Isolation Condenser (RCIC) System and Safety Relief Valves (SRV). Average mass flow of coolant that correspond this event is 20 kg/s and could keep reactor core from uncovered about 73 hours and fully uncovered in 75 hours later. There are three coolant regulating system at operational on reactor unit 3, Reactor Core Isolation Condenser (RCIC) system, High Pressure Coolant Injection (HPCI) system and Safety Relief Valves (SRV). Average mass flow of water that correspond this event is 15 kg/s and could keep reactor core from uncovered about 37 hours and fully uncovered in 40 hours later.

  4. [Prevention of bicycle accidents].

    Science.gov (United States)

    Zwipp, H; Barthel, P; Bönninger, J; Bürkle, H; Hagemeister, C; Hannawald, L; Huhn, R; Kühn, M; Liers, H; Maier, R; Otte, D; Prokop, G; Seeck, A; Sturm, J; Unger, T

    2015-04-01

    For a very precise analysis of all injured bicyclists in Germany it would be important to have definitions for "severely injured", "seriously injured" and "critically injured". By this, e.g., two-thirds of surgically treated bicyclists who are not registered by the police could become available for a general analysis. Elderly bicyclists (> 60 years) are a minority (10 %) but represent a majority (50 %) of all fatalities. They profit most by wearing a helmet and would be less injured by using special bicycle bags, switching on their hearing aids and following all traffic rules. E-bikes are used more and more (145 % more in 2012 vs. 2011) with 600,000 at the end of 2011 and are increasingly involved in accidents but still have a lack of legislation. So even for pedelecs 45 with 500 W and a possible speed of 45 km/h there is still no legislative demand for the use of a protecting helmet. 96 % of all injured cyclists in Germany had more than 0.5 ‰ alcohol in their blood, 86 % more than 1.1 ‰ and 59 % more than 1.7 ‰. Fatalities are seen in 24.2 % of cases without any collision partner. Therefore the ADFC calls for a limit of 1.1 ‰. Some virtual studies conclude that integrated sensors in bicycle helmets which would interact with sensors in cars could prevent collisions or reduce the severity of injury by stopping the cars automatically. Integrated sensors in cars with opening angles of 180° enable about 93 % of all bicyclists to be detected leading to a high rate of injury avoidance and/or mitigation. Hanging lamps reduce with 35 % significantly bicycle accidents for children, traffic education for children and special trainings for elderly bicyclists are also recommended as prevention tools. As long as helmet use for bicyclists in Germany rates only 9 % on average and legislative orders for using a helmet will not be in force in the near future, coming up campaigns seem to be necessary to be promoted by the Deutscher

  5. [Prevention of bicycle accidents].

    Science.gov (United States)

    Zwipp, H; Barthel, P; Bönninger, J; Bürkle, H; Hagemeister, C; Hannawald, L; Huhn, R; Kühn, M; Liers, H; Maier, R; Otte, D; Prokop, G; Seeck, A; Sturm, J; Unger, T

    2015-04-01

    For a very precise analysis of all injured bicyclists in Germany it would be important to have definitions for "severely injured", "seriously injured" and "critically injured". By this, e.g., two-thirds of surgically treated bicyclists who are not registered by the police could become available for a general analysis. Elderly bicyclists (> 60 years) are a minority (10 %) but represent a majority (50 %) of all fatalities. They profit most by wearing a helmet and would be less injured by using special bicycle bags, switching on their hearing aids and following all traffic rules. E-bikes are used more and more (145 % more in 2012 vs. 2011) with 600,000 at the end of 2011 and are increasingly involved in accidents but still have a lack of legislation. So even for pedelecs 45 with 500 W and a possible speed of 45 km/h there is still no legislative demand for the use of a protecting helmet. 96 % of all injured cyclists in Germany had more than 0.5 ‰ alcohol in their blood, 86 % more than 1.1 ‰ and 59 % more than 1.7 ‰. Fatalities are seen in 24.2 % of cases without any collision partner. Therefore the ADFC calls for a limit of 1.1 ‰. Some virtual studies conclude that integrated sensors in bicycle helmets which would interact with sensors in cars could prevent collisions or reduce the severity of injury by stopping the cars automatically. Integrated sensors in cars with opening angles of 180° enable about 93 % of all bicyclists to be detected leading to a high rate of injury avoidance and/or mitigation. Hanging lamps reduce with 35 % significantly bicycle accidents for children, traffic education for children and special trainings for elderly bicyclists are also recommended as prevention tools. As long as helmet use for bicyclists in Germany rates only 9 % on average and legislative orders for using a helmet will not be in force in the near future, coming up campaigns seem to be necessary to be promoted by the Deutscher

  6. Transcriptional profiling of human breast cancer cells cultured under microgravity conditions revealed the key role of genetic gravity sensors previously detected in Drosophila melanogaster

    Science.gov (United States)

    Valdivia-Silva, Julio E.; Lavan, David; Diego Orihuela-Tacuri, M.; Sanabria, Gabriela

    2016-07-01

    Currently, studies in Drosophila melanogaster has shown emerging evidence that microgravity stimuli can be detected at the genetic level. Analysis of the transcriptome in the pupal stage of the fruit flies under microgravity conditions versus ground controls has suggested the presence of a few candidate genes as "gravity sensors" which are experimentally validated. Additionally, several studies have shown that microgravity causes inhibitory effects in different types of cancer cells, although the genes involved and responsible for these effects are still unknown. Here, we demonstrate that the genes suggested as the sensors of gravitational waves in Drosophila melanogaster and their human counterpart (orthologous genes) are highly involved in carcinogenesis, proliferation, anti-apoptotic signals, invasiveness, and metastatic potential of breast cancer cell tumors. The transcriptome analyses suggested that the observed inhibitory effect in cancer cells could be due to changes in the genetic expression of these candidates. These results encourage the possibility of new therapeutic targets managed together and not in isolation.

  7. The evolution of computerized displays in accident management

    International Nuclear Information System (INIS)

    Key regulations implemented by the NRC in 1982, which included requirements such as upgraded emergency operating procedures, detailed control room design reviews, the addition of a safety parameter display system, and the inclusion of a degreed shift technical advisor as part of the operating staff, have enabled the use of computerized displays to evolve as an integral part of accident management within each of the four main vendor groups. Problems, however, remain to be resolved in the area of technical content, information reliability, and rules for use in order to achieve the goal of more reliable accident management in nuclear power plants

  8. OSSA - An optimized approach to severe accident management: EPR application

    International Nuclear Information System (INIS)

    There is a recognized need to provide nuclear power plant technical staff with structured guidance for response to a potential severe accident condition involving core damage and potential release of fission products to the environment. Over the past ten years, many plants worldwide have implemented such guidance for their emergency technical support center teams either by following one of the generic approaches, or by developing fully independent approaches. There are many lessons to be learned from the experience of the past decade, in developing, implementing, and validating severe accident management guidance. Also, though numerous basic approaches exist which share common principles, there are differences in the methodology and application of the guidelines. AREVA/Framatome-ANP is developing an optimized approach to severe accident management guidance in a project called OSSA ('Operating Strategies for Severe Accidents'). There are still numerous operating power plants which have yet to implement severe accident management programs. For these, the option to use an updated approach which makes full use of lessons learned and experience, is seen as a major advantage. Very few of the current approaches covers all operating plant states, including shutdown states with the primary system closed and open. Although it is not necessary to develop an entirely new approach in order to add this capability, the opportunity has been taken to develop revised full scope guidance covering all plant states in addition to the fuel in the fuel building. The EPR includes at the design phase systems and measures to minimize the risk of severe accident and to mitigate such potential scenarios. This presents a difference in comparison with existing plant, for which severe accidents where not considered in the design. Thought developed for all type of plants, OSSA will also be applied on the EPR, with adaptations designed to take into account its favourable situation in that field

  9. Chernobyl accident: lessons learned for radiation protection

    International Nuclear Information System (INIS)

    implementation of good known effective countermeasures at early stage could have substantially reduced the number of thyroid cancer cases after accident. U N Chernobyl Forum recommended long-term activity for mitigation Chernobyl's consequences - A Strategy for Recovery. For improvement this strategy must be create the modern system of the radiation protection based on the new international and national recommendations. The key issues of the Belarusian experience is discussed. (author)

  10. Biogenesis of Fe/S proteins and pathogenicity: IscR plays a key role in allowing Erwinia chrysanthemi to adapt to hostile conditions.

    Science.gov (United States)

    Rincon-Enriquez, Gabriel; Crété, Patrice; Barras, Frédéric; Py, Béatrice

    2008-03-01

    The Erwinia chrysanthemi genome is predicted to encode three systems, Nif, Isc and Suf, known to assist Fe/S cluster biogenesis and the CsdAE cysteine desulphurase. Single iscU, hscA and fdx mutants were found sensitive to paraquat and exhibited reduced virulence on both chicory leaves and Arabidopsis thaliana. Depletion of the whole Isc system led to a pleiotropic phenotype, including sensitivity to both paraquat and 2,2'-dipyridyl, auxotrophies for branched-chain amino acids, thiamine, nicotinic acid, and drastic alteration in virulence. IscR was able to suppress all of the phenotypes listed above in a sufC-dependent manner while depletion of the Isc system led to IscR-dependent activation of the suf operon. No virulence defects were found associated with csdA or nifS mutations. Surprisingly, we found that the sufC mutant was virulent against A. thaliana, whereas its virulence had been found altered in Saintpaulia. Collectively, these results lead us to propose that E. chrysanthemi possess the Fe/S biogenesis strategy suited to the physico-chemical conditions encountered in its host upon infection. In this view, the IscR regulator, which controls both Isc and Suf, is predicted to play a major role in the ability of E. chrysanthemi to colonize a wide array of different plants. PMID:18284573

  11. Three Mile Island Accident Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Three Mile Island Accident Data consists of mostly upper air and wind observations immediately following the nuclear meltdown occurring on March 28, 1979, near...

  12. Enhancement of organizational resilience in light of the Fukushima Dai-ichi Nuclear Power Plant accident (1). Analysis of responding structure

    International Nuclear Information System (INIS)

    Through the critical situations experienced at the Fukushima Daiichi Nuclear Power Plant accident, it became evident that plant personnel are the essential driving force toward resilience for mitigating the severe nuclear accident. In such situation, the key factors are skill and attitude of human operators who struggled sincerely against the accident. It is also evident that future nuclear safety needs to aim at Safety- which is a newly introduced notion of safety proposed in conjunction with resilience engineering. Safety-I was defined as a condition where as little as possible went wrong;. Safety-II is defined as a condition where as much as possible goes wright. Among the four core capabilities (i.e. Learning, Responding, Monitoring, Anticipating) proposed in the framework of resilience engineering, the constituents of 'Responding' is mainly studied in this paper. Four constituents such as Skill Attitude, Health and Environment have been identified through in-depth reviewing of accident reports and reflection of one of the authors who served as a unit director of Fukushima Daiichi Nuclear Power Plant. (author)

  13. 29 CFR 1960.29 - Accident investigation.

    Science.gov (United States)

    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...

  14. 49 CFR 801.32 - Accident reports.

    Science.gov (United States)

    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...

  15. The measurement of accident-proneness

    NARCIS (Netherlands)

    As, Sicco van

    2001-01-01

    This paper deals with the measurement of accident-proneness. Accidents seem easy to observe, however accident-proneness is difficult to measure. In this paper I first define the concept of accident-proneness, and I develop an instrument to measure it. The research is mainly executed within chemical

  16. 49 CFR 230.22 - Accident reports.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Accident reports. 230.22 Section 230.22... Requirements § 230.22 Accident reports. In the case of an accident due to failure, from any cause, of a steam... persons, the railroad on whose line the accident occurred shall immediately make a telephone report of...

  17. 49 CFR 845.40 - Accident report.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Accident report. 845.40 Section 845.40... RULES OF PRACTICE IN TRANSPORTATION; ACCIDENT/INCIDENT HEARINGS AND REPORTS Board Reports § 845.40 Accident report. (a) The Board will issue a detailed narrative accident report in connection with...

  18. New approach to optimize operational conditions for the biological treatment of a high-strength thiocyanate and ammonium waste: pH as key factor.

    Science.gov (United States)

    Lay-Son, Meiling; Drakides, Christian

    2008-02-01

    Biological treatment of coke and steel-processing wastewaters has to satisfy both industrial economic needs and environmental protection regulations. Nevertheless, as some of the pollutants contained in these waters or produced during the treatment are highly toxic, an effective and safe treatment has proved to be difficult to obtain. This paper reports the study of a biological method for the treatment of wastewaters containing free cyanide, thiocyanate and ammonium (NH4). Laboratory-scale activated-sludge reactors were fed with a synthetic solution reproducing a steel-processing industrial wastewater and inoculated with the same industrial bacterial seeding used on-site (Ecosynergie Inc.). The results demonstrated that free cyanide and thiocyanate were efficiently degraded. Nevertheless, thiocyanate degradation and nitrification processes were actually inhibited by the free ammonia form (NH3) in place of the ionized NH4 form (NH4+) currently dosed and often unproperly named "ammonia" [IUPAC, 1997. In: McNaught, A.D., Wilkinson, A. (compilers). Compendium of Chemical Terminology. Royal Society of Chemistry, Cambridge, UK]. Optimum degradation rates were obtained for very narrow ranges of ammonia nitrogen (NH3-N) concentrations. This result can be explained by the role of pH, which mainly controls the NH3/NH4 equilibrium. Pollutants and NH3 concentrations influenced degradation rates of main pollutants. This influence was determined and expressed through elementary equations. Although the Michaelis-Menten equation could have been used to describe thiocyanate degradation, a Haldane-inhibition model was used to satisfactorily describe cyanide degradation. On the other hand, a slightly modified Haldane model was applied to describe both NH4 oxidation using NH3-N as substrate and thiocyanate degradation using NH3-N as inhibitor. These findings emphasize the role of pH on degradation rates and allow one to optimize operational conditions in the biological treatment of

  19. Nuclear fuel cycle facility accident analysis handbook

    International Nuclear Information System (INIS)

    The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the radiological risk from accidents in nuclear fuel cycle facility operations. The AAH will enable the user to calculate source term releases from accident scenarios manually or by computer. A major feature of the AAH is development of accident sample problems to provide input to source term analysis methods and transport computer codes. Sample problems and illustrative examples for different accident types are included in the AAH

  20. Nuclear fuel cycle facility accident analysis handbook

    Energy Technology Data Exchange (ETDEWEB)

    Ayer, J E; Clark, A T; Loysen, P; Ballinger, M Y; Mishima, J; Owczarski, P C; Gregory, W S; Nichols, B D

    1988-05-01

    The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the radiological risk from accidents in nuclear fuel cycle facility operations. The AAH will enable the user to calculate source term releases from accident scenarios manually or by computer. A major feature of the AAH is development of accident sample problems to provide input to source term analysis methods and transport computer codes. Sample problems and illustrative examples for different accident types are included in the AAH.

  1. CARNSORE: Hypothetical reactor accident study

    International Nuclear Information System (INIS)

    Two types of design-basis accident and a series of hypothetical core-melt accidents to a 600 MWe reactor are described and their consequences assessed. The PLUCON 2 model was used to calculate the consequences which are presented in terms of individual and collective doses, as well as early and late health consequences. The site proposed for the nucelar power station is Carnsore Point, County Wexford, south-east Ireland. The release fractions for the accidents described are those given in WASH-1400. The analyses are based on the resident population as given in the 1979 census and on 20 years of data from the meteorological stations at Rosslare Harbour, 8.5 km north of the site. The consequences of one of the hypothetical core-melt accidents are described in detail in a meteorological parametric study. Likewise the consequences of the worst conceivable combination of situations are described. Finally, the release fraction in one accident is varied and the consequences of a proposed, more probable ''Class 9 accident'' are presented. (author)

  2. OFFSITE RADIOLOGICAL CONSEQUENCE ANALYSIS FOR THE BOUNDING FLAMMABLE GAS ACCIDENT

    International Nuclear Information System (INIS)

    This document quantifies the offsite radiological consequences of the bounding flammable gas accident for comparison with the 25 rem Evaluation Guideline established in DOE-STD-3009, Appendix A. The bounding flammable gas accident is a detonation in a SST. The calculation applies reasonably conservative input parameters in accordance with guidance in DOE-STD-3009, Appendix A. The purpose of this analysis is to calculate the offsite radiological consequence of the bounding flammable gas accident. DOE-STD-3009-94, ''Preparation Guide for US. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', requires the formal quantification of a limited subset of accidents representing a complete set of bounding conditions. The results of these analyses are then evaluated to determine if they challenge the DOE-STD-3009-94, Appendix A, ''Evaluation Guideline,'' of 25 rem total effective dose equivalent in order to identify and evaluate safety-class structures, systems, and components. The bounding flammable gas accident is a detonation in a single-shell tank (SST). A detonation versus a deflagration was selected for analysis because the faster flame speed of a detonation can potentially result in a larger release of respirable material. A detonation in an SST versus a double-shell tank (DST) was selected as the bounding accident because the estimated respirable release masses are the same and because the doses per unit quantity of waste inhaled are greater for SSTs than for DSTs. Appendix A contains a DST analysis for comparison purposes

  3. The computer aided education and training system for accident management

    International Nuclear Information System (INIS)

    Under severe accident conditions of a nuclear power plant, plant operators and technical support center (TSC) staffs will be under a amount of stress. Therefore, those individuals responsible for managing the plant should promote their understanding about the accident management and operations. Moreover, it is also important to train in ordinary times, so that they can carry out accident management operations effectively on severe accidents. Therefore, the education and training system which works on personal computers was developed by Japanese BWR group (Tokyo Electric Power Co.,Inc., Tohoku Electric Power Co. ,Inc., Chubu Electric Power Co. ,Inc., Hokuriku Electric Power Co.,Inc., Chugoku Electric Power Co.,Inc., Japan Atomic Power Co.,Inc.), and Hitachi, Ltd. The education and training system is composed of two systems. One is computer aided instruction (CAI) education system and the other is education and training system with a computer simulation. Both systems are designed to execute on MS-Windows(R) platform of personal computers. These systems provide plant operators and technical support center staffs with an effective education and training tool for accident management. TEPCO used the simulation system for the emergency exercise assuming the occurrence of hypothetical severe accident, and have performed an effective exercise in March, 2000. (author)

  4. Psychological distress and post-traumatic symptoms following occupational accidents.

    Science.gov (United States)

    Ghisi, Marta; Novara, Caterina; Buodo, Giulia; Kimble, Matthew O; Scozzari, Simona; Di Natale, Arianna; Sanavio, Ezio; Palomba, Daniela

    2013-12-01

    Depression and post-traumatic stress disorder frequently occur as a consequence of occupational accidents. To date, research has been primarily focused on high-risk workers, such as police officers or firefighters, and has rarely considered individuals whose occupational environment involves the risk of severe, but not necessarily life-threatening, injury. Therefore, the present study was aimed at assessing the psychological consequences of accidents occurring in several occupational settings (e.g., construction and industry). Thirty-eight victims of occupational accidents (injured workers) and 38 gender-, age-, and years of education-matched workers who never experienced a work accident (control group) were recruited. All participants underwent a semi-structured interview administered by a trained psychologist, and then were requested to fill in the questionnaires. Injured workers reported more severe anxious, post-traumatic and depressive symptoms, and poorer coping skills, as compared to controls. In the injured group low levels of resilience predicted post-traumatic symptomatology, whereas the degree of physical injury and the length of time since the accident did not play a predictive role. The results suggest that occupational accidents may result in a disabling psychopathological condition, and that a brief psychological evaluation should be included in the assessment of seriously injured workers. PMID:25379258

  5. Radiological accidents: education for prevention and confrontation

    International Nuclear Information System (INIS)

    The purpose of this work is to train and inform on radiological accidents as a preventive measure to improve the people life quality. Radiological accidents are part of the events of technological origin which are composed of nuclear and radiological accidents. As a notable figure is determined that there have been 423 radiological accidents from 1944 to 2005 and among the causes prevail industrial accidents, by irradiations, medical accidents and of laboratories, among others. Latin American countries such as Argentina, Brazil, Mexico and Peru are some where most accidents have occurred by radioactivity. The radiological accidents can have sociological, environmental, economic, social and political consequences. In addition, there are scenarios of potential nuclear accidents and in them the potential human consequences. Also, the importance of the organization and planning in a nuclear emergency is highlighted. Finally, the experience that Cuba has lived on the subject of radiological accidents is described

  6. Geochemistry of rare earth elements in the Baba Ali magnetite skarn deposit, western Iran – a key to determine conditions of mineralisation

    Directory of Open Access Journals (Sweden)

    Zamanian Hassan

    2016-03-01

    Full Text Available The Baba Ali skarn deposit, situated 39 km to the northwest of Hamadan (Iran, is the result of a syenitic pluton that intruded and metamorphosed the diorite host rock. Rare earth element (REE values in the quartz syenite and diorite range between 35.4 and 560 ppm. Although the distribution pattern of REEs is more and less flat and smooth, light REEs (LREEs in general show higher concentrations than heavy REEs (HREEs in different lithounits. The skarn zone reveals the highest REE-enriched pattern, while the ore zone shows the maximum depletion pattern. A comparison of the concentration variations of LREEs (La–Nd, middle REEs (MREEs; Sm–Ho and HREEs (Er–Lu of the ore zone samples to the other zones elucidates two important points for the distribution of REEs: 1 the distribution patterns of LREEs and MREEs show a distinct depletion in the ore zone while representing a great enrichment in the skarn facies neighbouring the ore body border and decreasing towards the altered diorite host rock; 2 HREEs show the same pattern, but in the exoskarn do not reveal any distinct increase as observed for LREEs and MREEs. The ratio of La/Y in the Baba Ali skarn ranges from 0.37 to 2.89. The ore zone has the highest La/Y ratio. In this regard the skarn zones exhibit two distinctive portions: 1 one that has La/Y >1 beingadjacent to the ore body and; 2 another one with La/Y < 1 neighbouring altered diorite. Accordingly, the Baba Ali profile, from the quartz syenite to the middle part of the exoskarn, demonstrates chiefly alkaline conditions of formation, with a gradual change to acidic towards the altered diorite host rocks. Utilising three parameters, Ce/Ce*, Eu/Eu* and (Pr/Ybn, in different minerals implies that the hydrothermal fluids responsible for epidote and garnet were mostly of magmatic origin and for magnetite, actinolite and phlogopite these were of magmatic origin with low REE concentration or meteoric water involved.

  7. Geochemistry of rare earth elements in the Baba Ali magnetite skarn deposit, western Iran - a key to determine conditions of mineralisation

    Science.gov (United States)

    Zamanian, Hassan; Radmard, Kaikosrov

    2016-03-01

    The Baba Ali skarn deposit, situated 39 km to the northwest of Hamadan (Iran), is the result of a syenitic pluton that intruded and metamorphosed the diorite host rock. Rare earth element (REE) values in the quartz syenite and diorite range between 35.4 and 560 ppm. Although the distribution pattern of REEs is more and less flat and smooth, light REEs (LREEs) in general show higher concentrations than heavy REEs (HREEs) in different lithounits. The skarn zone reveals the highest REE-enriched pattern, while the ore zone shows the maximum depletion pattern. A comparison of the concentration variations of LREEs (La-Nd), middle REEs (MREEs; Sm-Ho) and HREEs (Er-Lu) of the ore zone samples to the other zones elucidates two important points for the distribution of REEs: 1) the distribution patterns of LREEs and MREEs show a distinct depletion in the ore zone while representing a great enrichment in the skarn facies neighbouring the ore body border and decreasing towards the altered diorite host rock; 2) HREEs show the same pattern, but in the exoskarn do not reveal any distinct increase as observed for LREEs and MREEs. The ratio of La/Y in the Baba Ali skarn ranges from 0.37 to 2.89. The ore zone has the highest La/Y ratio. In this regard the skarn zones exhibit two distinctive portions: 1) one that has La/Y >1 beingadjacent to the ore body and; 2) another one with La/Y < 1 neighbouring altered diorite. Accordingly, the Baba Ali profile, from the quartz syenite to the middle part of the exoskarn, demonstrates chiefly alkaline conditions of formation, with a gradual change to acidic towards the altered diorite host rocks. Utilising three parameters, Ce/Ce*, Eu/Eu* and (Pr/Yb)n, in different minerals implies that the hydrothermal fluids responsible for epidote and garnet were mostly of magmatic origin and for magnetite, actinolite and phlogopite these were of magmatic origin with low REE concentration or meteoric water involved.

  8. Severe accidents due to windsurfing in the Aegean Sea.

    Science.gov (United States)

    Kalogeromitros, A; Tsangaris, H; Bilalis, D; Karabinis, A

    2002-06-01

    Windsurfing is a popular sport and has recently become an Olympic event. As an open-air water activity that requires the participant to be in perfect physical condition, windsurfers may be prone to accidents when certain basic rules or procedures are violated. The current study monitored severe injuries due to windsurfing over a period of 12 months in the Aegean Sea in Greece. Our study revealed 22 cases of severe accidents due to windsurfing, with a wide range of injuries including head injuries, spinal cord injuries, and severe fractures of the extremities. Prolonged hospitalization, severe disability and two deaths occurred as consequences of these accidents. The study examined the characteristics of these patients and the possible risk factors and conditions associated with the accidents. We also focused on the most common types of injuries and reviewed the mechanisms that may provoke them. Water sports and particularly windsurfing represent a major challenge for the emergency medical system, especially in the Aegean Sea. Hundreds of islands, kilometres of isolated coasts, millions of tourists, an extended summer period and rapidly changing weather create conditions that constantly test the efficacy of the emergency services. The development of an appropriate infrastructure and maximum control of the risk factors causing these accidents could reduce the morbidity and mortality that, unfortunately but rather predictably, accompany this popular summer activity. PMID:12131638

  9. Waste form characterization and its relationship to transportation accident analysis

    International Nuclear Information System (INIS)

    The response of potential waste forms should be determined for extreme transportation environments that must be postulated for environmental impact analysis and also for hypothetical accident conditions to which packagings and contents must be subjected for licensing purposes. The best approach may be to test materials up to and beyond their failure point; such an approach would establish failure thresholds. Specification of what denotes failure would be defined by existing or proposed regulations or dictated by requirements developed from accident analysis. Responses to physical and thermal insults are the most important for licensing or analysis and need to be thoroughly characterized. Others in need of characterization might be responses to extreme chemical environments and to intense and prolonged radiation exposure. A complete characterization of waste-form responses would be desirable for environments that are considered extreme for transportation accidents but which may be typical for processing or disposal environments. In addition, the characterizations that are performed must be completed in laboratory environments which can be readily correlated to accident environments and must be meaningfully conveyed to a transportation impact analyst. As an example, leaching data as commonly presented are not usable to the analyst and are obtained under conditions that are not directly applicable to conditions of most transportation accidents. Transportation analysts are in need of data useful for calculating environmental impacts and for licensing of packagings. Future waste form development programs and associated decisions should consider the needs of transportation analysts

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

    Science.gov (United States)

    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.

  11. [Accidents of fulguration].

    Science.gov (United States)

    Virenque, C; Laguerre, J

    1976-01-01

    Fulguration, first electric accident in which the man was a victim, is to day better known. A clap of thunder is decomposed in two elements: lightning, and thunder. Lightning is caused by an electrical discharge, either within a cloud, or between two clouds, or, above all, between a cloud and the surface of the ground. Experimental equipments owned by the French Electricity Company and by the Atomic Energy Commission, have allowed to photograph lightnings and to measure certain physical characteristics (Intensity variable between 25 to 100 kA, voltage variable between 20 to 1 000 kV). The frequency of storms was learned: the isokeraunic level, in France, is about 20, meaning that thunder is heard twenty days during one year. Man may be stricken by thunder by direct hit, by sudden bursting, by earth current, or through various conductors. The electric charge which reached him may go to the earth directly by contact with the ground or may dissipate in the air through a bony promontory (elbow). The total number of victims, "wounded" or deceased, is not now known by statistics. Death comes by insulation breakdown of one of several anatomic cephalic formations: skull, meninx, brain. Many various lesions may happen in survivors: loss of consciousness, more or less long, sensorial or motion deficiencies. All these signs are momentary and generally reversible. Besides one may observe much more intense lesions on the skin: burns and, over all, characteristic aborescence (skin effect by high frequency current). The heart is protected, contrarily to what happens with industrial electrocution. The curative treatment is merely symptomatic : reanimation, surgery for burns or associated traumatic lesions. A prevention is researched to help the lonely man, in the country or in the mountains in the houses (lightning conductor, Faraday cage), in vehicles (aircraft, cars, ships). The mysterious and unforseeable character of lightning still stays, leaving a door opened for numerous

  12. Quantifying safety benefit of winter road maintenance: accident frequency modeling.

    Science.gov (United States)

    Usman, Taimur; Fu, Liping; Miranda-Moreno, Luis F

    2010-11-01

    This research presents a modeling approach to investigate the association of the accident frequency during a snow storm event with road surface conditions, visibility and other influencing factors controlling for traffic exposure. The results have the premise to be applied for evaluating different maintenance strategies using safety as a performance measure. As part of this approach, this research introduces a road surface condition index as a surrogate measure of the commonly used friction measure to capture different road surface conditions. Data from various data sources, such as weather, road condition observations, traffic counts and accidents, are integrated and used to test three event-based models including the Negative Binomial model, the generalized NB model and the zero inflated NB model. These models are compared for their capability to explain differences in accident frequencies between individual snow storms. It was found that the generalized NB model best fits the data, and is most capable of capturing heterogeneity other than excess zeros. Among the main results, it was found that the road surface condition index was statistically significant influencing the accident occurrence. This research is the first showing the empirical relationship between safety and road surface conditions at a disaggregate level (event-based), making it feasible to quantify the safety benefits of alternative maintenance goals and methods.

  13. Attenuation of airborne debris from LMFBR accidents

    International Nuclear Information System (INIS)

    Experimental and theoretical studies have been performed to characterize the behavior of airborne particulates (aerosols) expected to be produced by hypothetical core disassembly accidents (HCDA's) in liquid metal fast breeder reactors (LMFBR's). These aerosol studies include work on aerosol transport in a 20-m high, 850-m3 closed vessel at moderate concentrations; aerosol transport in a small vessel under conditions of high concentration (approximately 1,000 g/m3), high turbulence, and high temperature (approximately 20000C); and aerosol transport through various leak paths. These studies have shown that tittle, if any, airborne debris from LMFBR HCDA's would reach the atmosphere exterior to an intact reactor containment building. (author)

  14. Attenuation of airborne debris from LMFBR accidents

    International Nuclear Information System (INIS)

    Experimental and theoretical studies have been performed to characterize the behavior of airborne particulates (aerosols) expected to be produced by hypothetical core disassembly accidents (HCDA's) in liquid metal fast breeder reactors (LMFBR's). These aerosol studies include work on aerosol transport in a 20-m high, 850-m3 closed vessel at moderate concentrations; aerosol transport in a small vessel under conditions of high concentration (approx. 1000 g/m3), high turbulence, and high temperature (approx. 20000C); and aerosol transport through various leak paths. These studies have shown that little, if any, airborne debris from LMFBR HCDA's would reach the atmosphere exterior to an intact reactor containment building

  15. The Fukushima Daiichi Accident. Technical Volume 1/5. Description and Context of the Accident

    International Nuclear Information System (INIS)

    This volume presents the key events that happened before, during and after the accident at the Fukushima Daiichi nuclear power plant (NPP), operated by the Tokyo Electric Power Company (TEPCO). The description of the event in this volume is based on objective and factual information, and is presented largely in a chronological manner. The volume also describes the Fukushima Daiichi NPP site, the reactor designs, the structure of the nuclear industry in Japan and the Japanese regulatory framework at the time of the accident. It describes in detail the earthquake, the tsunami, the events at the Fukushima Daiichi NPP and the actions taken there and elsewhere for post-accident management up to December 2014. The description of the events is largely based on information provided by the Government of Japan to the IAEA; reports of the investigation committees established by the Japanese Government, the National Diet of Japan and TEPCO, including updates and supplements by TEPCO; the regulatory body; and the IAEA missions listed in Section 1.6.5. Information is provided without judgement and evaluation, unless it is necessary to clarify a certain occurrence assessments are contained in Technical Volumes 2 to 5

  16. Implications for accident management of adding water to a degrading reactor core

    International Nuclear Information System (INIS)

    This report evaluates both the positive and negative consequences of adding water to a degraded reactor core during a severe accident. The evaluation discusses the earliest possible stage at which an accident can be terminated and how plant personnel can best respond to undesired results. Specifically discussed are (a) the potential for plant personnel to add water for a range of severe accidents, (b) the time available for plant personnel to act, (c) possible plant responses to water added during the various stages of core degradation, (d) plant instrumentation available to understand the core condition and (e) the expected response of the instrumentation during the various stages of severe accidents

  17. Implications for accident management of adding water to a degrading reactor core

    Energy Technology Data Exchange (ETDEWEB)

    Kuan, P.; Hanson, D.J.; Pafford, D.J.; Quick, K.S.; Witt, R.J. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1994-02-01

    This report evaluates both the positive and negative consequences of adding water to a degraded reactor core during a severe accident. The evaluation discusses the earliest possible stage at which an accident can be terminated and how plant personnel can best respond to undesired results. Specifically discussed are (a) the potential for plant personnel to add water for a range of severe accidents, (b) the time available for plant personnel to act, (c) possible plant responses to water added during the various stages of core degradation, (d) plant instrumentation available to understand the core condition and (e) the expected response of the instrumentation during the various stages of severe accidents.

  18. Multiscale Multiphysics Developments for Accident Tolerant Fuel Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Gamble, K. A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hales, J. D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Yu, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhang, Y. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bai, X. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Andersson, D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Patra, A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wen, W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tome, C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baskes, M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Martinez, E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stanek, C. R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Miao, Y. [Argonne National Lab. (ANL), Argonne, IL (United States); Ye, B. [Argonne National Lab. (ANL), Argonne, IL (United States); Hofman, G. L. [Argonne National Lab. (ANL), Argonne, IL (United States); Yacout, A. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Liu, W. [ANATECH Corp., San Diego, CA (United States)

    2015-09-01

    U3Si2 and iron-chromium-aluminum (Fe-Cr-Al) alloys are two of many proposed accident-tolerant fuel concepts for the fuel and cladding, respectively. The behavior of these materials under normal operating and accident reactor conditions is not well known. As part of the Department of Energy’s Accident Tolerant Fuel High Impact Problem program significant work has been conducted to investigate the U3Si2 and FeCrAl behavior under reactor conditions. This report presents the multiscale and multiphysics effort completed in fiscal year 2015. The report is split into four major categories including Density Functional Theory Developments, Molecular Dynamics Developments, Mesoscale Developments, and Engineering Scale Developments. The work shown here is a compilation of a collaborative effort between Idaho National Laboratory, Los Alamos National Laboratory, Argonne National Laboratory and Anatech Corp.

  19. Safety and reliability in industrial organizations - The key factors

    International Nuclear Information System (INIS)

    A survey-based technique has been developed that measures and generates comparative data on important organizational, work group, and job-level variables that are directly related to on-the-job accidents. This paper describes the results of an analysis of data from more than 2,700 employees in the chemical, oil, construction, and wood products industries. These analyses indicate that several key variables are significantly related to accidents in the workplace

  20. Environmental consequences of releases from nuclear accidents

    International Nuclear Information System (INIS)

    The report presents the results of a four-year Nordic cooperation project (AKTU-200). The results have impact upon many facets of accident consequence assessment, ranging from new computational tools to recommendations concerning food preparation methods to be utilized in a fallout situation. Some of the subprojects have approached areas where little or no research has been performed previously, like the project on winter conditions, the project on the physico/chemical form of radionuclides in the Chernobyl fallout, and the project on resuspension. The conclusion from the first of these projects is that the impact of an accident or fallout situation occuring during winter may be considerable smaller than in a similar situation during summer conditions. The most important conclusion from the second of these projects is that bioavailability of radiocesium in soil is significantly lower than that of radiocesium in plant material taken up via the roots. In the third project is was found that the resuspension factor is several orders of magnitude lower than the values traditionally cited, and that resuspension is a local phenomenon in a majority of weather conditions. The development of large-scale testing of mitigating actions to prevent uptake of radiocesium in animals in a fallout situation is also one of the projects where new ground has been sucessfully broken. 189 refs., 89 figs., 55 tabs

  1. Effect of steam-exhaust operation of secondary coolant circuit on ship reactor blackout accident

    International Nuclear Information System (INIS)

    Highlights: • The ship reactor blackout accident (SRBA) is simulated by the RELAP5/MOD3.2 code. • The mitigation effect of steam-exhaust-operation (SEO) on the SRBA is analyzed. • Reasonable SEO scheme can obviously mitigate the accident for several hours. • The SEO scheme without feed water device can hardly mitigate the SRBA. • The failure of intercurrent steam flux control valve will result in the decrease of mitigation time. - Abstract: The ship reactor blackout accident can potentially lead to the severe accident and the radioactive fission product release. In the absence of auxiliary electrical source, the effective mitigation of the accident aftereffect is very important. As the exclusive heat trap in the reactor coolant system, the steam-exhaust operation (SEO) in the secondary coolant circuit (SCC) plays an important role in the accident mitigation. In view of the character of ship nuclear power plant (NPP), the ship reactor blackout accident (SRBA) under the typical operating conditions is simulated by the RELAP5/MOD3.2 code, and the mitigation of SEO on the accident is analyzed. It is found that (1) reasonable SEO can obviously mitigate the accident for several hours, the SEO with 1% rated steam flux of secondary coolant circuit provides about 7 h for the mitigation of accident, (2) a less steam flux of SCC during the SEO means a slower pressure drop of steam generation (SG) and a more time we can mitigate the accident, there are 1.5 h between the SEO with 1% rated steam flux and that with 3% rated steam flux, (3) the SEO without the feed water device can hardly mitigate the accident, and (4) during the blackout accident, the SEO with intercurrent steam flux control valve failure will result in the decrease of mitigation time because of the quick decrease of SG pressure, but the mitigation effect is also obvious

  2. [Diagnosis and treatment of diving accidents. New German guidelines for diving accidents 2014-2017].

    Science.gov (United States)

    Jüttner, B; Wölfel, C; Liedtke, H; Meyne, K; Werr, H; Bräuer, T; Kemmerer, M; Schmeißer, G; Piepho, T; Müller, O; Schöppenthau, H

    2015-06-01

    In 2015 the German Society for Diving and Hyperbaric Medicine (GTÜM) and the Swiss Underwater and Hyperbaric Medical Society (SUHMS) published the updated guidelines on diving accidents 2014-2017. These multidisciplinary guidelines were developed within a structured consensus process by members of the German Interdisciplinary Association for Intensive Care and Emergency Medicine (DIVI), the Sports Divers Association (VDST), the Naval Medical Institute (SchiffMedInst), the Social Accident Insurance Institution for the Building Trade (BG BAU), the Association of Hyperbaric Treatment Centers (VDD) and the Society of Occupational and Environmental Medicine (DGAUM). This consensus-based guidelines project (development grade S2k) with a representative group of developers was conducted by the Association of Scientific Medical Societies in Germany. It provides information and instructions according to up to date evidence to all divers and other lay persons for first aid recommendations to physician first responders and emergency physicians as well as paramedics and all physicians at therapeutic hyperbaric chambers for the diagnostics and treatment of diving accidents. To assist in implementing the guideline recommendations, this article summarizes the rationale, purpose and the following key action statements: on-site 100% oxygen first aid treatment, still patient positioning and fluid administration are recommended. Hyperbaric oxygen (HBO) recompression remains unchanged the established treatment in severe cases with no therapeutic alternatives. The basic treatment scheme recommended for diving accidents is hyperbaric oxygenation at 280 kPa. For quality management purposes there is a need in the future for a nationwide register of hyperbaric therapy.

  3. Nuclear installations abroad the accident risks and their potential consequences

    International Nuclear Information System (INIS)

    This paper endeavors to assess the threat to Ireland from severe accidents at civil nuclear installations. Among the various types of nuclear installations worldwide, reactors and reprocessing plants are considered to be the most threatening and so the paper focuses on these. The threat is assumed to be a function of the risk of severe accidents at the above types of installations and the probability of unfavourable weather conditions carrying the radioactive releases to Ireland. Although nuclear installations designed in eastern Europe and Asia are less safe than others, the greatest threat to Ireland arises from nearby installations in the UK. The difficulty of measuring the probabilities and consequences of severe nuclear accidents at nuclear installations in general is explained. In the case of the UK installations, this difficulty is overcome to some degree by using values of 'tolerable' risk adopted by the national nuclear regulator to define the radiotoxic releases from nuclear accidents. These are used as input to atmospheric dispersion models in which unfavourable weather conditions for Ireland are assumed and radiation doses are calculated to members of the Irish public. No countermeasures, such as sheltering, are assumed. In the worst cast scenario no deaths would be expected in Ireland in the immediate aftermath of the accident however, an increase in cancers over a period of 25 years or so would be expected assuming present-day models for the effect of low level radiation are valid

  4. RETRAC, Reactor Core Accident Simulation

    International Nuclear Information System (INIS)

    1 - Description of program or function: The RETRAC code uses a set of coupled neutron point-kinetics equations and thermal-hydraulic conservation laws to simulate nuclear reactor core behaviour under transient or accident conditions. The reactor core is represented by single equivalent unit cells composed of three regions: fuel, clad, and moderator (coolant). 2 - Method of solution: At each time step, core thermal power is calculated by solving a set of six delayed neutron group kinetics equations with adjusted reactivity feedbacks. The numerical resolution is performed by using the Runge-Kutta-Gill method. The externally inserted reactivity is specified in the input data file, whereas Doppler, fuel, clad, and water temperature reactivity feedbacks are calculated by the code itself. Core cooling is treated as a homogeneous one-dimensional fluid flow through a representative unit cell composed of three successive regions: fuel, clad, and coolant. Several flow regime models are considered for both single- and two-phase states of the coolant. The conservation laws are solved by the method of characteristics coupled with an implicit finite difference scheme to ensure stability and convergence of the numerical algorithm. Validation tests of the RETRAC code were performed by using the International Atomic Energy Agency 10-MW benchmark cores, for protected transients. Further assessment studies are in progress using experimental data. 3 - Restrictions on the complexity of the problem: The RETRAC code uses steady-state thermal-hydraulic correlations. Their use is not always justified, but it seems to be quite useful in quasi-steady cases such as as loss-of-flow transients

  5. Radioactive materials transport accident analysis

    Energy Technology Data Exchange (ETDEWEB)

    McSweeney, T.I.; Maheras, S.J.; Ross, S.B. [Battelle Memorial Inst. (United States)

    2004-07-01

    Over the last 25 years, one of the major issues raised regarding radioactive material transportation has been the risk of severe accidents. While numerous studies have shown that traffic fatalities dominate the risk, modeling the risk of severe accidents has remained one of the most difficult analysis problems. This paper will show how models that were developed for nuclear spent fuel transport accident analysis can be adopted to obtain estimates of release fractions for other types of radioactive material such as vitrified highlevel radioactive waste. The paper will also show how some experimental results from fire experiments involving low level waste packaging can be used in modeling transport accident analysis with this waste form. The results of the analysis enable an analyst to clearly show the differences in the release fractions as a function of accident severity. The paper will also show that by placing the data in a database such as ACCESS trademark, it is possible to obtain risk measures for transporting the waste forms along proposed routes from the generator site to potential final disposal sites.

  6. Nuclear law and radiological accidents

    International Nuclear Information System (INIS)

    Nuclear activities in Brazil, and particularly the radiological accident of Goiania, are examined in the light of the environmental and nuclear laws of Brazil and the issue of responsibility. The absence of legislation covering radioactive wastes as well as the restrictions on Brazilian States to issue regulations covering nuclear activities are reviewed. The radiological accident and its consequences, including the protection and compensation of the victims, the responsibility of the shareholders of the Instituto Goiano de Radioterapia, operator of the radioactive source, the provisional storage and the final disposal at Abadia de Goias of the radioactive waste generated by the accident are reviewed. Finally, nuclear responsibility, the inapplicability of the Law 6453/77 which deals with nuclear damages, and the state liability regime are analysed in accordance with the principles of the Brazilian Federal Constitution. (author)

  7. Severe accident management guidelines tool

    International Nuclear Information System (INIS)

    Severe Accident is addressed by means of a great number of documents such as guidelines, calculation aids and diagnostic trees. The response methodology often requires the use of several documents at the same time while Technical Support Centre members need to assess the appropriate set of equipment within the adequate mitigation strategies. In order to facilitate the response, TECNATOM has developed SAMG TOOL, initially named GGAS TOOL, which is an easy to use computer program that clearly improves and accelerates the severe accident management. The software is designed with powerful features that allow the users to focus on the decision-making process. Consequently, SAMG TOOL significantly improves the severe accident training, ensuring a better response under a real situation. The software is already installed in several Spanish Nuclear Power Plants and trainees claim that the methodology can be followed easier with it, especially because guidelines, calculation aids, equipment information and strategies availability can be accessed immediately (authors)

  8. Severe accident simulation at Olkiuoto

    Energy Technology Data Exchange (ETDEWEB)

    Tirkkonen, H.; Saarenpaeae, T. [Teollisuuden Voima Oy (TVO), Olkiluoto (Finland); Cliff Po, L.C. [Micro-Simulation Technology, Montville, NJ (United States)

    1995-09-01

    A personal computer-based simulator was developed for the Olkiluoto nuclear plant in Finland for training in severe accident management. The generic software PCTRAN was expanded to model the plant-specific features of the ABB Atom designed BWR including its containment over-pressure protection and filtered vent systems. Scenarios including core heat-up, hydrogen generation, core melt and vessel penetration were developed in this work. Radiation leakage paths and dose rate distribution are presented graphically for operator use in diagnosis and mitigation of accidents. Operating on an graphically for operator use in diagnosis and mitigation of accidents. Operating on an 486 DX2-66, PCTRAN-TVO achieves a speed about 15 times faster than real-time. A convenient and user-friendly graphic interface allows full interactive control. In this paper a review of the component models and verification runs are presented.

  9. Internal Accident Report on EDH

    CERN Multimedia

    SC Department

    2006-01-01

    The A2 Safety Code requires that, the Internal Accident Report form must be filled in by the person concerned or any witness to ensure that all the relevant services are informed. Please note that an electronic version of this form has been elaborated in collaboration with SC-IE, HR-OPS-OP and IT-AIS. Whenever possible, the electronic form shall be used. The relative icon is available on the EDH Desktop, Other tasks page, under the Safety heading, or directly here: https://edh.cern.ch/Document/Accident/. If you have any questions, please contact the SC Secretariat, tel. 75097 Please notice that the Internal Accident Report is an integral part of the Safety Code A2 and does not replace the HS50.

  10. Corporate Cost of Occupational Accidents

    DEFF Research Database (Denmark)

    Rikhardsson, Pall M.; Impgaard, M.

    2004-01-01

    for a company with 3.600 employees was estimated to approximately US$ 682.000. The paper includes an introduction regarding accident cost analysis in companies, a presentation of the SACA project methodology and the SACA method itself, a short overview of some of the results of the SACA project and a conclusion......The systematic accident cost analysis (SACA) project was carried out during 2001 by The Aarhus School of Business and PricewaterhouseCoopers Denmark with financial support from The Danish National Working Environment Authority. Its focused on developing and testing a method for evaluating...... occupational costs of companies for use by occupational health and safety professionals. The method was tested in nine Danish companies within three different industry sectors and the costs of 27 selected occupational accidents in these companies were calculated. One of the main conclusions is that the SACA...

  11. Road characteristics and bicycle accidents.

    Science.gov (United States)

    Nyberg, P; Björnstig, U; Bygren, L O

    1996-12-01

    In Umeå, Sweden, defects in the physical road surface contributed to nearly half of the single bicycle accidents. The total social cost of these injuries to people amount to at least SEK 20 million (SEK 60,000 or about USD 8,500 per accident), which corresponds to the estimated loss of "eight life equivalents a year". Improved winter maintenance seems to have the greatest injury prevention potential and would probably reduce the number of injuries considerably, whereas improved road quality and modification of kerbs would reduce the most severe injuries. A local traffic safety program should try to prevent road accidents instead of handling the consequences of them. In accordance with Parliament decisions on traffic we would like to see increased investment in measures favoring bicycle traffic, where cycling is seen as a solution, not as a problem.

  12. Hindsight Bias in Cause Analysis of Accident

    Institute of Scientific and Technical Information of China (English)

    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.

  13. The child accident repeater: a review.

    Science.gov (United States)

    Jones, J G

    1980-04-01

    The child accident repeater is defined as one who has at least three accidents that come to medical attention within a year. The accident situation has features in common with those of the child who has a single accident through simple "bad luck", but other factors predispose him to repeated injury. In the child who has a susceptible personality, a tendency for accident repetition may be due to a breakdown in adjustment to a stressful environment. Prevention of repeat accidents should involve the usual measures considered appropriate for all children as well as an attempt to provide treatment of significant maladjustment and modification of a stressful environment.

  14. JCO criticality accident termination operation

    International Nuclear Information System (INIS)

    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)

  15. Road Traffic Accidents in Kazakhstan

    Directory of Open Access Journals (Sweden)

    Alma Aubakirova

    2013-03-01

    Full Text Available Background: The article provides the analysis of death rates in road traffic accidents in Kazakhstan from 2004 to 2010 and explores the use of sanitary aviation.Methods: Data of fatalities caused by road traffic accidents were collected and analysed. Descriptive and analytical methods of epidemiology and biomedical statistics were applied.Results: Totaly 27,003 people died as a result of road traffic accidents in this period. The death rate for the total population due to road traffic accidents was 25.0±2.10/0000. The death rate for men was (38.3±3.20/0000, which was higher (P<0.05 than that for women (12.6±1.10/0000. High death rates in the entire male population were identified among men of 30-39 years old, whereas the highest rates for women were attributed to the groups of 50-59 years old and 70-79 years old. In time dynamics, death rates tended to decrease: the total population (Тdec=−2.4%, men (Тdec=−2.3% and women (Тdec=−1.4%. When researching territorial relevance, the rates were established as low (to 18.30/0000, average (between18.3 and24.00/0000 and high (from 24.00/0000 and above. Thus, the regions with high rates included Akmola region (24.30/0000, Mangistau region (25.90/0000, Zhambyl region (27.30/0000, Almaty region (29.30/0000 and South Kazakhstan region (32.40/0000.Conclusion: The identified epidemiological characteristics of the population deaths rates from road traffic accidents should be used in integrated and targeted interventions to enhance prevention of injuries in accidents.

  16. Analysis on Causes of Electrical Shock Accident of Fountain%喷水池电击事故起因简析

    Institute of Scientific and Technical Information of China (English)

    王厚余

    2012-01-01

    Electrical shock accident of fountain occurs frequently in China. Electrical equipments with a voltage of 220 V and above should be used for fountain and over-high voltage will result in electrical shock accident underwater. The author believes that different from that above ground, the electrical shock accident of fountain is mainly caused by underground voltage gradient or electric field. Therefore, relevant analysis is conducted and key points to prevent electrical shock accident during electrical design under the current conditions in China are presented.%我国喷水池电击事故屡有发生。喷水池内电气设备需采用220V及以上电压,过高电压在水下很易引发电击事故。作者认为喷水池内电击事故的发生与地面上不同,它主要由水下电压梯度或电场引起。故对此进行分析,并提出在我国现时条件下喷水池电气设计中防电击的要点。

  17. Fatal motorcycle accidents and alcohol

    DEFF Research Database (Denmark)

    Larsen, C F; Hardt-Madsen, M

    1987-01-01

    A series of fatal motorcycle accidents from a 7-year period (1977-1983) has been analyzed. Of the fatalities 30 were operators of the motorcycle, 11 pillion passengers and 8 counterparts. Of 41 operators 37% were sober at the time of accident, 66% had measurable blood alcohol concentration (BAC......); 59% above 0.08%. In all cases where a pillion passenger was killed, the operator of the motorcycle had a BAC greater than 0.08%. Of the killed counterparts 2 were non-intoxicated, 2 had a BAC greater than 0.08%, and 4 were not tested. The results advocate that the law should restrict alcohol...

  18. Brookhaven lecture series No. 227: The Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Kouts, H.

    1986-09-24

    This lecture discusses the events leading to, during, and following the Chernobyl Reactor number 4 accident. A description of the light water cooled, graphite moderated reactor, the reactor site conditions leading to meltdown is presented. The emission of radioactive effluents and the biological radiation effects is also discussed. (FI)

  19. Planning and modalities of intervention in case of transportation accidents

    International Nuclear Information System (INIS)

    An accident occurring during the transportation of radioactive materials may entail various consequences for the population and the environment. Intervention handling in case of an accident may involve a previsional aspect of assessment of the possible consequences and an operational phase of application of conservation measures. Following a transportation accident it is very important to quickly localize the place of the accident and to make a rapid assessment of the probable consequences. This is the role of the intervention teams. First of all, they should be able to arrive as quickly as possible on the spot and to limit the consequences, so the intervention teams should be located in centers not too far away from the frequented itineraries and have a perimeter or operating radius well defined. Second, they should dispose of adequate equipment as remote handling equipment for hostile environment if required. Terrestrial transportation (rail and road) represent the major part of radioactive transportations. The consequences of an accident have been quickly evaluated in the case of spent fuels transportation. It shall be noticed that some provisions of the international regulations may be interpreted in a more or less restrictive manner and that results in various evaluations of the risk. In the case of an accident occurring during sea transportation, it seems that the accidental conditions should be different and sometimes more severe than those usually considered for the testing and certification of the casks. It is the case for the duration of a fire and temperature attained during a fire. Thus the intervention may be more difficult and necessitate more important means and international coordination. Borderline accidents will need previous concertation between potential concerned countries and coordination of emergency places

  20. Hull loss accident model for narrow body commercial aircraft

    Directory of Open Access Journals (Sweden)

    Somchanok Tiabtiamrat

    2010-10-01

    Full Text Available Accidents with narrow body aircraft were statistically evaluated covering six families of commercial aircraft includingBoeing B737, Airbus A320, McDonnell Douglas MD80, Tupolev TU134/TU154 and Antonov AN124. A risk indicator for eachflight phase was developed based on motion characteristics, duration time, and the presence of adverse weather conditions.The estimated risk levels based on these risk indicators then developed from the risk indicator. Regression analysis indicatedvery good agreement between the estimated risk level and the accident ratio of hull loss cases per number of delivered aircraft.The effect of time on the hull loss accident ratio per delivered aircraft was assessed for B737, A320 and MD80. Equationsrepresenting the effect of time on hull loss accident ratio per delivered aircraft were proposed for B737, A320, and MD80,while average values of hull loss accident ratio per delivered aircraft were found for TU134, TU154, and AN 124. Accidentprobability equations were then developed for each family of aircraft that the probability of an aircraft in a hull loss accidentcould be estimated for any aircraft family, flight phase, presence of adverse weather factor, hour of day, day of week, monthof year, pilot age, and pilot flight hour experience. A simplified relationship between estimated hull loss accident probabilityand unsafe acts by human was proposed. Numerical investigation of the relationship between unsafe acts by human andfatality ratio suggested that the fatality ratio in hull loss accident was dominated primarily by the flight phase media.

  1. Post-accident gas generation from radiolysis of organic materials

    International Nuclear Information System (INIS)

    This report presents a methodology for estimating the gas generation rates resulting from radiolysis of organic materials in paints and electrical cable insulation inside a nuclear reactor containment building under design basis accident conditions. The methodology was based on absorption of the radiation energies from the post-accident fission products and the assumed gas yields of the irradiated materials. A sample calculation was made using conservative assumptions, plant-specific data of a nuclear power plant, and a radiation source term which took into account the time-dependent release and physico-chemical behavior of the fission products

  2. Proceedings of the Specialist Meeting on Severe Accident Management Programme Development

    International Nuclear Information System (INIS)

    Effective Accident Management planning can produce both a reduction in the frequency of severe accidents at nuclear power plants as well as the ability to mitigate a severe accident. The purpose of an accident management programme is to provide to the responsible plant staff the capability to cope with the complete range of credible severe accidents. This requires that appropriate instrumentation and equipment are available within the plant to enable plant staff to diagnose the faults and to implement appropriate strategies. The programme must also provide the necessary guidance, procedures, and training to assure that appropriate corrective actions will be implemented. One of the key issues to be discussed is the transition from control room operations and the associated emergency operating procedures to a technical support team approach (and the associated severe accident management strategies). Following a proposal made by the Senior Group of Experts on Severe Accident Management (SESAM), the Committee on the Safety of Nuclear Installations decided to sponsor a Specialist Meeting on Severe Accident Management Programme Development. The general objectives of the Specialist Meeting were to exchange experience, views, and information among the participants and to discuss the status of severe accident management programmes. The meeting brought together utilities, accident management programme developers, personnel training programme developers, regulators, and researchers. In general, the tone of the Specialist Meeting - designed to promote progress, as contrasted with conferences or symposia where the state-of-the-art is presented - was to be rather practical, and focus on accident management programme development, applications, results, difficulties and improvements. As shown by the conclusions of the meeting, there is no doubt that this objective was widely attained

  3. Radiation protection experience in Yugoslavia from the Vinca accident to nowadays

    International Nuclear Information System (INIS)

    This Paper is the expression of the author opinion about development of radiation protection in Yugoslavia from its beginning forty years ago, which might affect its status in the foreseeable future at the first decades of the 21st century. It focuses on key events in this field starting from the Vinca Accident, which happened in the October 1958, to nowadays. Shortly reviewed some of key events are: Vinca Accident; Foundation of the Radiation Protection Laboratory in the Vinca Institute; International Vinca Dosimetry Experiment; First National Symposium and foundation of the Yugoslav Radiation Protection Association; International Intercomparison Experiment on Nuclear Accident Dosimetry and, International Summer Schools and Symposium on Radiation Protection organized in Yugoslavia. Finally, some specific experimental data obtained during and after Chernobyl Accident up to nowadays in radiation protection action in Yugoslavia are presented also. (author)

  4. Feasibility of Accident-Tolerant FCM Replacement Fuel for CANDUs

    International Nuclear Information System (INIS)

    For enhanced accident tolerance, an innovative fuel concept, the fully ceramic microencapsulated (FCM) fuel based on the particle fuel concept of a gas-cooled reactor, is proposed to replace the conventional UO2 fuel bundle of existing and advanced CANDU reactors. In this study, the feasibility of replacing conventional UO2 fuel bundle with the accident-tolerant FCM fuel bundle has been assessed in view of core neutronics compatibility, accident-tolerance, and fuel cycle management. From the study, it was demonstrated that the FCM replacement fuel can provide resolution to CANDU generic issues by ensuring not only enhanced accident tolerance, but also an improved fuel cycle management. The accident-tolerant FCM fuel concept is proposed for replacing the conventional UO2 fuel bundle in CANDUs. The FCM fuel is shown to be neutronically compatible with existing core and the core residence time can be increased by more than 100 days. Accident-tolerance is remarkably enhanced by key features of the FCM fuel: it is refractory, thermo-mechanically and chemically stable, and fission product retentive. Less fuel feed and discharge obtained with the FCM fuel provide large savings in the spent fuel management burden charge and reduces the burden to the spent fuel storage facility in the long run. The smaller amount of minor actinides in the discharge bundles, together with the fission product retention and corrosion resistant features of the FCM fuel, should facilitate the long-term dry disposals of the spent fuel. From this study, it has been demonstrated that the CANDU FCM fuel is a feasible and viable option for CANDU reactors. The technology readiness level of the FCM fuel design and manufacturing is close to a lead test bundle loading for near-term deployment

  5. Industrial accidents in nuclear power plants

    International Nuclear Information System (INIS)

    In 12 nuclear power plants in the Federal Republic of Germany with a total of 3678 employees, 25 notifiable company personnel accidents and 46 notifiable outside personnel accidents were reported for an 18-month period. (orig./HP)

  6. Road Accident Trends in Africa and Europe

    DEFF Research Database (Denmark)

    Jørgensen, N O

    1997-01-01

    The paper decribes trends and suggests prediction models for accident risks in African and European countries......The paper decribes trends and suggests prediction models for accident risks in African and European countries...

  7. 49 CFR 229.17 - Accident reports.

    Science.gov (United States)

    2010-10-01

    ... CFR part 225. ... 49 Transportation 4 2010-10-01 2010-10-01 false Accident reports. 229.17 Section 229.17..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS General § 229.17 Accident reports. (a)...

  8. How to reduce the number of accidents

    CERN Multimedia

    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

  9. Independent accident investigation: a modern safety tool

    International Nuclear Information System (INIS)

    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. Neutronic static analysis of Chernobyl accident

    International Nuclear Information System (INIS)

    In the present analysis, estimates were made of the positive reactivity introduced through the growth of the coolant void fraction in a Graphite-water steam-generating reactor both at the average value of burnup given by the Soviets and at the maximum value. Using Monte Carlo models, various possible axial distribution of burnup, displacer models, conditions in the control channels and positions of the control rods were considered in calculating the insertion of positive reactivity with the fall of the manual and emergency control rods; that is the positive scram. The possibility of positive reactivity insertion due to the creation of a mixture of fuel, water and cladding in a number of central fuel channels has been examined. This situation corresponds to the explosion of these channels, and is considered in the present work as the cause of the second reactivity peak. At the level of the data presented in this study, vaporization of cooling water in the fuel channels can be considered as the cause of the Chernobyl accident. The accident began in the region of the channels close to the axis of the reactor and spread to its periphery. The positive reactivity due to insertion of the manual and emergency control rods - positive scram -played a marginal role in the development of the accident. Fracture of the fuel followed by bursting of the channels around the axis of the reactor, due to contact between the hot UO2 particles and the cooling water at th end of the first peak, could have started a mechanism capable of producing a second peak in reactivity, in the case of fuel damage extended to a sufficiently large portion of the core

  11. Best practices to reduce the accident rate hotel

    Science.gov (United States)

    García Revilla, M. R.; Kahale Carrillo, D. T.

    2014-10-01

    Examining the available databases and existing tourism organizations can conclude that appear studies on accidents and their relationship with other variables. But in our case we want to assess this relationship in the performance of the hotel in relation to lower the accident rate. The Industrial Safety studies analyzing this accident causes (why they happen), their sources (committed activities), their agents (participants work means), its type (how the events occur or develop), all in order to develop prevention. In our case, as accidents happen because people commit wrongful acts or because the equipment, tools, machinery or workplaces are not in proper conditions, the preventive point of view we analyze through the incidence of workplace accidents hotel subsector. The crash occurs because there is a risk, so that adequate control of it would avoid despite individual factors. Absenteeism or absence from work was taken into account first by Dubois in 1977, as he realized the time lost in the nineteenth century due to the long working hours, which included the holidays. Motivation and job satisfaction were the elements that have been most important in the phenomenon of social psychology.

  12. Consequence of potential accidents in heavy water plants

    International Nuclear Information System (INIS)

    Heavy water plants realize the primary isotopic concentrations of water using H2O-H2S chemical exchange and they are chemical plants. As these plants are handling and spreading large quantities of hydrogen sulphide (high toxic, corrosive, flammable and explosive as) maintained in the process at relative high temperatures and pressures, it is required an assessing of risks associated with the potential accidents. The H2S released in atmosphere as a result of an accident will have negative consequences to property, population and environment. This paper presents a model of consequences quantitative assessment and its outcome for the most dangerous accident in heavy water plants. Several states of the art risk based methods were modified and linked together to form a proper model for this analyse. Five basic steps to identify the risks involved in operating the plants are followed: hazard identification, accident sequence development, H2S emissions calculus, dispersion analyses and consequences determination. A brief description of each step and some information of analysis results are provided. The accident proportions, the atmospheric conditions and the population density in the respective area were accounted for consequences calculus. The specific results of the consequences analysis allow to develop the plant's operating safety requirements so that the risk remain at an acceptable level. (authors)

  13. Development of emergency response support system for accident management

    International Nuclear Information System (INIS)

    Specific measures for the accident management (AM) are proposed to prevent the severe accident and to mitigate their effects in order to upgrade the safety of nuclear power plants even further. To ensure accident management effective, it is essential to grasp the plant status accurately. In consideration of the above mentioned background, the Emergency Response Support System (ERSS) was developed as a computer assisted prototype system by a joint study of Japanese BWR group. This system judges and predicts the plant status at the emergency condition in a nuclear power plant. This system displays the results of judgment and prediction. The effectiveness of the system was verified through the test and good prospects for applying the system to a plant was obtained. 7 refs., 10 figs

  14. Tourist visitation impacts of the accident at Three Mile Island

    International Nuclear Information System (INIS)

    This paper analyzes tourist visitation impacts of the March 27, 1979 accident at Three Mile Island. A review of the literature, supplemented with recollections from Pennsylvanian public officials, are used to specify a conventional tourism impact model which holds that depressed 1979 summer tourism season was more influenced by gasoline shortages and possibly other confounding variables (such as rainy local weather conditions and a polio outbreak) than by the nuclear accident. Regression analysis using monthly visitation data for Hershey Chocolate World, Gettysburg National Park, The Pennsylvania Dutch Convention and Visitor Bureau, and several state parks as dependent variables provide support for this model. Potential tourism implications of an accident at Yucca Mountain are briefly discussed in light of our findings

  15. Long term cooling analysis after Fukushima Daiichi accident

    International Nuclear Information System (INIS)

    The objective of this study is to analyze of the long term cooling after Fukushima Daiichi accident by RELAP5mode3.3 code and to check the validity of the cooling method. In order to simulate the cooling conditions in Fukushima plants after accident, the model is nodalized on the assumption of the existence of steam/liquid leak position from RPV/PCV and the variety of debris distribution in RPV/PCV. As a result, we estimated the debris distribution in RPV by referring plant parameter such as reactor pressure and temperature. In addition, we performed the analysis of the loss of injection water accident for the current cooling system installed in Fukushima Daiichi cite after the earthquake. In this case, we develop simplified nodalization of RPV to analyze temperature behavior of reactor structural materials by using the radiation heat transfer model. (author)

  16. Cesium-137 accident lessons in Goiania, Goias State, Brazil

    International Nuclear Information System (INIS)

    This document relates the experience obtained by several professionals which had an important role in the cesium-137 accident occurred in Goiania, Goias State, Brazil in September, 1987. It's divided into chapters, according to the action area - medical, nursing, social assistance, odontological and psychological. At first, some notions of radioprotection are explained, followed by the accident history and by the doctors and nurses action during the emergency phase and the medical, odontological, social and psychological assistance to the victims. The social assistance report shows some statistical data about the economic, occupational and social conditions of the accident victims. It is shown some information about the health institutions and the sanitary care in the ionizing radiation and about the occupational radiological protection in Goiania

  17. Factors Associated with Road Accidents among Brazilian Motorcycle Couriers

    Directory of Open Access Journals (Sweden)

    Daniela Wosiack da Silva

    2012-01-01

    , were included in the study. Young age (18 to 24 years compared to ≥25 years, odds ratio [OR]=1.77 speeding (OR=1.48, and use of cell phones while driving (OR=1.43 were factors independently associated with reports of accidents. For serious accidents, there was an association with alternation of work shifts (OR=1.91 and speeding (OR=1.67. The characteristics associated with accidents—personal (young age, behavioral (use of cell phones while driving and speeding, and professional (speeding and alternation of work shifts—reveal the need to adopt wide-ranging strategies to reduce these accidents, including better work conditions for these motorcyclists.

  18. Response of personal radiation detectors to simulated criticality accident pulses

    International Nuclear Information System (INIS)

    Personal radiation detection instruments (PRDIs) are often used to augment the protection provided by the installed criticality accident alarm system (CAAS). ANSI/ANS-8.3-1997 provides examples of situations when PRDIs could be used, including hor ellipsisalarm system maintenance or testing, evacuation drills, activities in areas not normally occupied by personnel, or other special operations. These instruments were designed for use in radiological control applications. Consequently, documented performance capabilities under conditions typical of the initial pulse from a criticality accident are not readily available. This paper describes testing performed to demonstrate the capability of the PRDIs to respond to radiation pulses similar to that which would be expected to occur in the event of a criticality accident. Detector responses for low-power, oscillating, or slow excursions were either available from manufacturing data or bounded by the initial pulse

  19. Accident consequence assessment code development

    International Nuclear Information System (INIS)

    This paper describes the new computer code system, OSCAAR developed for off-site consequence assessment of a potential nuclear accident. OSCAAR consists of several modules which have modeling capabilities in atmospheric transport, foodchain transport, dosimetry, emergency response and radiological health effects. The major modules of the consequence assessment code are described, highlighting the validation and verification of the models. (author)

  20. New technology for accident prevention

    Energy Technology Data Exchange (ETDEWEB)

    Byne, P. [Shiftwork Solutions, Vancouver, BC (Canada)

    2006-07-01

    This power point presentation examined the effects of fatigue in the workplace and presented 3 technologies designed to prevent or monitor fatigue. The relationship between mental fatigue, circadian rhythms and cognitive performance was explored. Details of vigilance related degradations in the workplace were presented, as well as data on fatigue-related accidents and a time-line of meter-reading errors. It was noted that the direct cause of the Exxon Valdez disaster was sleep deprivation. Fatigue related accidents during the Gulf War were reviewed. The effects of fatigue on workplace performance include impaired logical reasoning and decision-making; impaired vigilance and attention; slowed mental operations; loss of situational awareness; slowed reaction time; and short cuts and lapses in optional or self-paced behaviours. New technologies to prevent fatigue-related accidents include (1) the driver fatigue monitor, an infra-red camera and computer that tracks a driver's slow eye-lid closures to prevent fatigue related accidents; (2) a fatigue avoidance scheduling tool (FAST) which collects actigraphs of sleep activity; and (3) SAFTE, a sleep, activity, fatigue and effectiveness model. refs., tabs., figs.

  1. Consequences of the Chernobyl accident

    International Nuclear Information System (INIS)

    A collection of three papers about the fallout in Austria from the 1986 Chernobyl reactor accident is given: 1. An overview of the research projects in Austria; 2. On the transfer into and uptake by crops and animal fodder; 3. On the reduction of cesium concentration in food. 18 tabs., 21 figs., 69 refs

  2. EAC european accident code. A modular system of computer programs to simulate LMFBR hypothetical accidents

    International Nuclear Information System (INIS)

    One aspect of fast reactor safety analysis consists of calculating the strongly coupled system of physical phenomena which contribute to the reactivity balance in hypothetical whole-core accidents: these phenomena are neutronics, fuel behaviour and heat transfer together with coolant thermohydraulics in single- and two-phase flow. Temperature variations in fuel, coolant and neighbouring structures induce, in fact, thermal reactivity feedbacks which are added up and put in the neutronics calculation to predict the neutron flux and the subsequent heat generation in the reactor. At this point a whole-core analysis code is necessary to examine for any hypothetical transient whether the various feedbacks result effectively in a negative balance, which is the basis condition to ensure stability and safety. The European Accident Code (EAC), developed at the Joint Research Centre of the CEC at Ispra (Italy), fulfills this objective. It is a modular informatics structure (quasi 2-D multichannel approach) aimed at collecting stand-alone computer codes of neutronics, fuel pin mechanics and hydrodynamics, developed both in national laboratories and in the JRC itself. EAC makes these modules interact with each other and produces results for these hypothetical accidents in terms of core damage and total energy release. 10 refs

  3. Safety against releases in severe accidents. Final report

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-01

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

  4. Safety against releases in severe accidents. Final report

    International Nuclear Information System (INIS)

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

  5. Trismus: An unusual presentation following road accident

    Directory of Open Access Journals (Sweden)

    Thakur Jagdeep

    2007-01-01

    Full Text Available Trismus due to trauma usually follows road accidents leading to massive faciomaxillary injury. In the literature there is no report of a foreign body causing trismus following a road accident, this rare case is an exception. We present a case of isolated presentation of trismus following a road accident. This case report stresses on the thorough evaluation of patients presenting with trismus following a road accident.

  6. Calculating nuclear accident probabilities from empirical frequencies

    OpenAIRE

    Ha-Duong, Minh; Journé, V.

    2014-01-01

    International audience Since there is no authoritative, comprehensive and public historical record of nuclear power plant accidents, we reconstructed a nuclear accident data set from peer-reviewed and other literature. We found that, in a sample of five random years, the worldwide historical frequency of a nuclear major accident, defined as an INES level 7 event, is 14 %. The probability of at least one nuclear accident rated at level ≥4 on the INES scale is 67 %. These numbers are subject...

  7. Effect of free media on views regarding nuclear energy after the Fukushima accident

    OpenAIRE

    YAMAMURA, Eiji

    2011-01-01

    Using cross-country data, this paper investigates how governance influenced views regarding the security of nuclear energy after the Fukushima accident in Japan. Key findings are: (1) citizens are less likely to agree that nuclear power plants are properly secured against accidents with the presence of a free media and higher levels of freedom of expression; and (2) freedom of expression and free media are positively associated with the presence of nuclear plants. These findings indicate that...

  8. Detection and analysis of accident black spots with even small accident figures.

    NARCIS (Netherlands)

    Oppe, S.

    1982-01-01

    Accident black spots are usually defined as road locations with high accident potentials. In order to detect such hazardous locations we have to know the probability of an accident for a traffic situation of some kind, or the mean number of accidents for some unit of time. In almost all procedures

  9. [Risk factors for accidents during sports while serving in German armed forces].

    Science.gov (United States)

    Gundlach, N; Sammito, S; Böckelmann, I

    2012-03-01

    In the German Armed Forces sports activities should bring the benefits of good health and trained fitness which are the hallmarks of sportsmen. In order to achieve this aim it is important to avoid accidents which negate the benefit of sports. Until today there appear to be no studies in existence which demonstrate the risk factors of sports activities undertaken while in military service. Equivalent studies on civilian sport activities are scarcely comparable. To find out risk factors for accidents with any period of recovery we followed sports accidents while on duty in a German barracks with 4,300 soldiers over a two-year period. Additionally we asked about the time needed for recovery from each accident, parameters of lifestyle, the body mass index and the possibility of a nightshift before each accident. We examined a minimum of 410 accidents. We found associations between the accidents studied and particular risk factors, including doing sports more than two times a week, being active in a fitness or sports club, having the accident together with another sportsman and doing a nightshift before the day of the accident. Bad ground conditions contributed to a large number of accidents. A body mass index of 25 and higher had a significantly prolonged time for recovery. To avoid accidents, sport and ground conditions should be adapted to each other. In addition, overweight people are not only compromised for cardiovascular and neurological diseases but also have a higher risk of needing a prolonged time for recovery, thus it is important that overweight should be avoided and not only just be treated. PMID:22422284

  10. Severe Accident Analysis for Combustible Gas Risk Evaluation inside CFVS

    Energy Technology Data Exchange (ETDEWEB)

    Lee, NaRae; Lee, JinYong; Bang, YoungSuk; Lee, DooYong [FNC Technology Co. Ltd., Yongin (Korea, Republic of); Kim, HyeongTaek [KHNP-Central Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The purpose of this study is to identify the composition of gases discharged into the containment filtered venting system by analyzing severe accidents. The accident scenarios which could be significant with respect to containment pressurization and hydrogen generation are derived and composition of containment atmosphere and possible discharged gas mixtures are estimated. In order to ensure the safety of the public and environment, the ventilation system should be designed properly by considering discharged gas flow rate, aerosol loads, radiation level, etc. One of considerations to be resolved is the risk due to combustible gas, especially hydrogen. Hydrogen can be generated largely by oxidation of cladding and decomposition of concrete. If the hydrogen concentration is high enough and other conditions like oxygen and steam concentration is met, the hydrogen can burn, deflagrate or detonate, which result in the damage the structural components. In particularly, after Fukushima accident, the hydrogen risk has been emphasized as an important contributor threatening the integrity of nuclear power plant during the severe accident. These results will be used to analyze the risk of hydrogen combustion inside the CFVS as boundary conditions. Severe accident simulation results are presented and discussed qualitatively with respect to hydrogen combustion. The hydrogen combustion risk inside of the CFVS has been examined qualitatively by investigating the discharge flow characteristics. Because the composition of the discharge flow to CFVS would be determined by the containment atmosphere, the severe accident progression and containment atmosphere composition have been investigated. Due to PAR operation, the hydrogen concentration in the containment would be decreased until the oxygen is depleted. After the oxygen is depleted, the hydrogen concentration would be increased. As a result, depending on the vent initiation timing (i.e. vent initiation pressure), the important

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 48 CFR 836.513 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Accident prevention. 836... prevention. The contracting officer must insert the clause at 852.236-87, Accident Prevention, in solicitations and contracts for construction that contain the clause at FAR 52.236-13, Accident Prevention....

  13. 48 CFR 1836.513 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Accident prevention. 1836... 1836.513 Accident prevention. The contracting officer must insert the clause at 1852.223-70, Safety and Health, in lieu of FAR clause 52.236-13, Accident Prevention, and its Alternate I....

  14. 48 CFR 636.513 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Accident prevention. 636... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 636.513 Accident prevention. (a) In... contracting activities shall insert DOSAR 652.236-70, Accident Prevention, in lieu of FAR clause...

  15. Severe Accidents in the Energy Sector

    Energy Technology Data Exchange (ETDEWEB)

    Hirschberg, S.; Spiekerman, G.; Dones, R

    1998-11-01

    A comprehensive database on severe accidents, with main emphasis on the ones associated with the energy sector, has been established by the Paul Scherrer Institute (PSI). Fossil energy carriers, nuclear power and hydro power are covered in ENSAD (Energy related Severe Accident Database), and the scope of work includes all stages of the analysed energy chains, i.e. exploration, extraction, transports, processing, storage and waste disposal. The database has been developed using a wide variety of sources. As opposed to the previous studies the ambition of the present work has been, whenever feasible, to cover a relatively broad spectrum of damage categories of interest. This includes apart from fatalities also serious injuries, evacuations, land or water contamination, and economic losses. Currently, ENSAD covers 13,914 accidents, of which 4290 are energy related, and 1943 are considered as severe accidents. Significant effort has been directed towards the examination of the relevance of the worldwide accident records to the Swiss specific conditions, particularly in the context of nuclear and hydro power. For example, a detailed investigation of large dam failures and their consequences was carried out. Generally, while Swiss specific aspects are emphasised, the major part of the collected and analysed data, as well as the insights gained, are considered to be of general interest. In particular, three sets of the aggregated results are provided based on world wide occurrence, on OECD countries, and on non OECD countries, respectively. Significant differences exist between the aggregated, normalised damage rates assessed for the various energy carriers: On the world wide basis, the broader picture obtained by coverage of full energy chains leads to aggregated immediate fatality rates being much higher for the fossil fuels than what one would expect if power plants only were considered. The highest rates apply to LPG, followed by hydro, oil, coal, natural gas and

  16. Severe Accidents in the Energy Sector

    International Nuclear Information System (INIS)

    A comprehensive database on severe accidents, with main emphasis on the ones associated with the energy sector, has been established by the Paul Scherrer Institute (PSI). Fossil energy carriers, nuclear power and hydro power are covered in ENSAD (Energy related Severe Accident Database), and the scope of work includes all stages of the analysed energy chains, i.e. exploration, extraction, transports, processing, storage and waste disposal. The database has been developed using a wide variety of sources. As opposed to the previous studies the ambition of the present work has been, whenever feasible, to cover a relatively broad spectrum of damage categories of interest. This includes apart from fatalities also serious injuries, evacuations, land or water contamination, and economic losses. Currently, ENSAD covers 13,914 accidents, of which 4290 are energy related, and 1943 are considered as severe accidents. Significant effort has been directed towards the examination of the relevance of the worldwide accident records to the Swiss specific conditions, particularly in the context of nuclear and hydro power. For example, a detailed investigation of large dam failures and their consequences was carried out. Generally, while Swiss specific aspects are emphasised, the major part of the collected and analysed data, as well as the insights gained, are considered to be of general interest. In particular, three sets of the aggregated results are provided based on world wide occurrence, on OECD countries, and on non OECD countries, respectively. Significant differences exist between the aggregated, normalised damage rates assessed for the various energy carriers: On the world wide basis, the broader picture obtained by coverage of full energy chains leads to aggregated immediate fatality rates being much higher for the fossil fuels than what one would expect if power plants only were considered. The highest rates apply to LPG, followed by hydro, oil, coal, natural gas and

  17. Fukushima nuclear power plant accident was preventable

    Science.gov (United States)

    Kanoglu, Utku; Synolakis, Costas

    2015-04-01

    , insufficient attention was paid to evidence of large tsunamis inundating the region, i.e., AD 869 Jogan and 1677 Empo Boso-oki tsunamis, and the 1896 Sanriku tsunami maximum height in eastern Japan whose maximum runup was 38m. Two, the design safety conditions were different in Onagawa, Fukushima and Tokai NPPs. It is inconceivable to have had different earthquake scenarios for the NPPs at such close distance from each other. Three, studying the sub-standard TEPCO analysis performed only months before the accident shows that it is not the accuracy of numerical computations or the veracity of the computational model that doomed the NPP, but the lack of familiarity with the context of numerical predictions. Inundation projections, even if correct for one particular scenario, need to always be put in context of similar studies and events elsewhere. To put it in colloquial terms, following a recipe from a great cookbook and having great cookware does not always result in great food, if the cook is an amateur. The Fukushima accident was preventable. Had the plant's owner TEPCO and NISA followed international best practices and standards, they would had predicted the possibility of the plant being struck by the size of tsunami that materialized in 2011. If the EDGs had been relocated inland or higher, there would have been no loss of power. A clear chance to have reduced the impact of the tsunami at Fukushima was lost after the 2010 Chilean tsunami. Standards are not only needed for evaluating the vulnerability of NPPs against tsunami attack, but also for evaluating the competence of modelers and evaluators. Acknowledgment: This work is partially supported by the project ASTARTE (Assessment, STrategy And Risk Reduction for Tsunamis in Europe) FP7-ENV2013 6.4-3, Grant 603839 to the Technical University of Crete and the Middle East Technical University.

  18. Influências das condições e organização do trabalho de uma indústria de transformação de cana-de-açúcar na ocorrência de acidentes de trabalho Influences of working conditions and organization in a sugar cane transformation industry in the event of accidents at work

    Directory of Open Access Journals (Sweden)

    Cassiano Ricardo Rumin

    2008-12-01

    Full Text Available Este estudo discute a relação entre as condições e a organização do trabalho como elementos que contribuem para a ocorrência de acidentes do trabalho. Os dados foram coletados em uma indústria produtora de açúcar, álcool e derivados, situada no Estado de São Paulo. Para a coleta dos dados utilizamos a observação direta do trabalho e realizamos entrevistas semidirigidas individuais como 22 trabalhadores do setor de produção de açúcar. A produção de açúcar foi indicada pela Equipe de Segurança e Higiene no Trabalho como o setor em que havia a maior ocorrência de acidentes. Por destacar o papel que a relação homem-trabalho desempenha na saúde física e psíquica dos trabalhadores, utilizamos a Psicodinâmica do Trabalho (Dejours, 1994 como referencial teórico para a análise dos dados obtidos nas entrevistas. A análise das entrevistas envolveu três aspectos: condições e organização do trabalho e insatisfação. Os resultados revelaram que o ambiente estudado apresenta fatores físicos, químicos e biológicos desfavoráveis à saúde dos trabalhadores. Quanto à organização do trabalho, os dados revelaram que a divisão do trabalho bem como o conteúdo das tarefas determinavam sobrecarga aos trabalhadores. O relato sobre a insatisfação envolveu: ausência de perspectiva para progressão profissional, falta de treinamento técnico, dificuldade em manejar equipamentos e inadequação dos equipamentos de proteção. Destaca-se também no discurso dos trabalhadores a ineficiência das ações organizacionais para a eliminação ou a neutralização dos riscos de acidentes do trabalho e a predominância da teoria do "Ato inseguro" na apuração da causalidade dos acidentes do trabalho.The present study is about the relationship between the work conditions and organization as elements that contribute to work accidents. The data were collected in a sugar cane industry that produces sugar, alcohol and other derivates

  19. Scratch Behaviors of Cr-Coated Zr-Based Fuel Claddings for Accident-Tolerant Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young-Ho; Kim, Il-Hyun; Kim, Hyun-Gil; Kim, Hyung-Kyu; Koo, Yang-Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    As the progression of Fukushima accident is worsened by the runaway reaction at a high temperature above 1200 .deg. C, it is essential to ensure the stabilities of coating layers on conventional Zr-based alloys during normal operations as well as severe accident conditions. This is because the failures of coating layer result in galvanic corrosion phenomenon by potential difference between coating layer and Zr alloy. Also, it is possible to damage the coating layer during handling and manufacturing process by contacting structural components of a fuel assembly. So, adhesion strength is one of the key factors determining the reliability of the coating layer on conventional Zr-based alloy. In this study, two kinds of Cr-coated Zr-based claddings were prepared using arc ion plating (AIP) and direct laser (DL) coating methods. The objective is to evaluate the scratch deformation behaviors of each coating layers on Zr alloys. Large area spallation below normal load of about 15 N appeared to be the predominant mode of failure in the AIP coating during scratch test. However, no tensile crack were found in entire stroke length. In DL coating, small plastic deformation and grooving behavior are more dominant scratching results. It was observed that the change of the slope of the COF curve did not coincide with the failure of coating layer.

  20. Comparative risk assessment of severe accidents in the energy sector

    International Nuclear Information System (INIS)

    Comparative assessment of accident risks in the energy sector is a key aspect in a comprehensive evaluation of sustainability and energy security concerns. Safety performance of energy systems can have important implications on the environmental, economic and social dimensions of sustainability as well as availability, acceptability and accessibility aspects of energy security. Therefore, this study provides a broad comparison of energy technologies based on the objective expression of accident risks for complete energy chains. For fossil chains and hydropower the extensive historical experience available in PSI's Energy-related Severe Accident Database (ENSAD) is used, whereas for nuclear a simplified probabilistic safety assessment (PSA) is applied, and evaluations of new renewables are based on a combination of available data, modeling, and expert judgment. Generally, OECD and EU 27 countries perform better than non-OECD. Fatality rates are lowest for Western hydropower and nuclear as well as for new renewables. In contrast, maximum consequences can be by far highest for nuclear and hydro, intermediate for fossil, and very small for new renewables, which are less prone to severe accidents. Centralized, low-carbon technology options could generally contribute to achieve large reductions in CO2-emissions; however, the principal challenge for both fossil with Carbon Capture and Storage and nuclear is public acceptance. Although, external costs of severe accidents are significantly smaller than those caused by air pollution, accidents can have disastrous and long-term impacts. Overall, no technology performs best or worst in all respects, thus tradeoffs and priorities are needed to balance the conflicting objectives such as energy security, sustainability and risk aversion to support rationale decision making. - Highlights: • Accident risks are compared across a broad range of energy technologies. • Analysis of historical experience was based on the