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Sample records for shielding protects nuclear

  1. Nuclear shields

    International Nuclear Information System (INIS)

    Linares, R.C.; Nienart, L.F.; Toelcke, G.A.

    1976-01-01

    A process is described for preparing melt-processable nuclear shielding compositions from chloro-fluoro substituted ethylene polymers, particularly PCTFE and E-CTFE, containing 1 to 75 percent by weight of a gadolinium compound. 13 claims, no drawings

  2. Guideline on radiation protection requirements for ionizing radiation shielding in nuclear power plants

    International Nuclear Information System (INIS)

    1988-01-01

    The guideline which entered into force on 1 May 1988 stipulates the radiation protection requirements for shielding against ionizing radiation to be met in the design, construction, commissioning, operation, and decommissioning of nuclear power plants

  3. Radiation protection/shield design

    International Nuclear Information System (INIS)

    Disney, R.K.

    1977-01-01

    Radiation protection/shielding design of a nuclear facility requires a coordinated effort of many engineering disciplines to meet the requirements imposed by regulations. In the following discussion, the system approach to Clinch River Breeder Reactor Plant (CRBRP) radiation protection will be described, and the program developed to implement this approach will be defined. In addition, the principal shielding design problems of LMFBR nuclear reactor systems will be discussed in realtion to LWR nuclear reactor system shielding designs. The methodology used to analyze these problems in the U.S. LMFBR program, the resultant design solutions, and the experimental verification of these designs and/or methods will be discussed. (orig.) [de

  4. Wake Shield Target Protection

    International Nuclear Information System (INIS)

    Valmianski, Emanuil I.; Petzoldt, Ronald W.; Alexander, Neil B.

    2003-01-01

    The heat flux from both gas convection and chamber radiation on a direct drive target must be limited to avoid target damage from excessive D-T temperature increase. One of the possibilities of protecting the target is a wake shield flying in front of the target. A shield will also reduce drag force on the target, thereby facilitating target tracking and position prediction. A Direct Simulation Monte Carlo (DSMC) code was used to calculate convection heat loads as boundary conditions input into ANSYS thermal calculations. These were used for studying the quality of target protection depending on various shapes of shields, target-shield distance, and protective properties of the shield moving relative to the target. The results show that the shield can reduce the convective heat flux by a factor of 2 to 5 depending on pressure, temperature, and velocity. The protective effect of a shield moving relative to the target is greater than the protective properties of a fixed shield. However, the protective effect of a shield moving under the drag force is not sufficient for bringing the heat load on the target down to the necessary limit. Some other ways of diminishing heat flux using a protective shield are discussed

  5. E-Alerts: Nuclear science and technology (radiation shielding, protection, and safety). E-mail newsletter

    International Nuclear Information System (INIS)

    1999-01-01

    Topics include: Shielding design, nuclear radiation transport properties of materials, decontamination; Container design and transportation requirements for radioactive materials; and Fallout shelters

  6. Status of the ITER tokamak nuclear shielding and radiological protection design

    Energy Technology Data Exchange (ETDEWEB)

    Leichtle, D., E-mail: dieter.leichtle@f4e.europa.eu [Fusion for Energy, Josep Pla 2, Barcelona 08019 (Spain); Chaffard, P.Y.; Izquierdo, J. [Fusion for Energy, Josep Pla 2, Barcelona 08019 (Spain); Juarez, R. [UNED, Juan del Rosal 12, Madrid 28040 (Spain); Pampin, R.; Portone, A. [Fusion for Energy, Josep Pla 2, Barcelona 08019 (Spain)

    2016-11-01

    Highlights: • Comprehensive review of design status of the ITER tokamak regarding nuclear shielding. • Investigation of shield design options and streaming mitigation measures. • Review of state-of-the-art shutdown dose rate analyses for selected port systems. - Abstract: Nuclear shielding of the ITER tokamak encompasses several systems and interfaces in a complex radiation environment. Therefore any shielding design has to involve a series of structures, systems and components in an integrated approach. This is evident for the complex ex-vessel radiation environment with streaming and leakage of plasma neutrons and subsequent activation of ex-vessel structures which give raise to excessive shutdown dose rates in accessible areas of the cryostat. The paper reviews recent nuclear analyses related to the performance of primary shields and highlights challenges toward an integrated nuclear shielding design. The general need of propagation of shielding requirements is highlighted in the context of radiation cross talk due to penetrations. Radiation streaming through gaps and penetrations is a key problem in any efficient shield design. The impact on the evolving radiation environment due to several design options along streaming paths such as port gaps, as well as their modeling for nuclear analysis, is presented. Implications regarding design integration and compliance with integrated shielding requirements and ALARA dose are finally given.

  7. Survey of radiation protection, radiation transport, and shielding information needs of the nuclear power industry. Final report

    International Nuclear Information System (INIS)

    Maskewitz, B.F.; Trubey, D.K.; Roussin, R.W.; McGill, B.L.

    1976-04-01

    The Radiation Shielding Information Center (RSIC) is engaged in a program to seek out, organize, and disseminate information in the area of radiation transport, shielding, and radiation protection. This information consists of published literature, nuclear data, and computer codes and advanced analytical techniques required by ERDA, its contractors, and the nuclear power industry to improve radiation analysis and computing capability. Information generated in this effort becomes a part of the RSIC collection and/or data base. The purpose of this report on project 219-1 is to document the results of the survey of information and computer code needs of the nuclear power industry in the area of radiation analysis and protection

  8. Survey of radiation protection, radiation transport, and shielding information needs of the nuclear power industry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Maskewitz, B.F.; Trubey, D.K.; Roussin, R.W.; McGill, B.L.

    1976-04-01

    The Radiation Shielding Information Center (RSIC) is engaged in a program to seek out, organize, and disseminate information in the area of radiation transport, shielding, and radiation protection. This information consists of published literature, nuclear data, and computer codes and advanced analytical techniques required by ERDA, its contractors, and the nuclear power industry to improve radiation analysis and computing capability. Information generated in this effort becomes a part of the RSIC collection and/or data base. The purpose of this report on project 219-1 is to document the results of the survey of information and computer code needs of the nuclear power industry in the area of radiation analysis and protection.

  9. Shields for nuclear reactors

    International Nuclear Information System (INIS)

    Aspden, G.J.

    1984-01-01

    The patent concerns shields for nuclear reactors. The roof shield comprises a normally fixed radial outer portion, a radial inner portion rotatable about a vertical axis, and a connection between the inner and outer portions. In the event of hypothecal core disruption conditions, a cantilever system on the inner wall allows the upward movement of the inner wall, in order to prevent loss of containment. (UK)

  10. Nuclear data for radiation shielding

    International Nuclear Information System (INIS)

    Miyasaka, Shunichi; Takahashi, Hiroshi.

    1976-01-01

    The third shielding expert conference was convened in Paris in Oct. 1975 for exchanging informations about the sensitivity evaluation of nuclear data in shielding calculation and integral bench mark experiment. The requirements about nuclear data presented at present from the field of nuclear design do not reflect sufficiently the requirements of shielding design, therefore it was the object to gather the requirements about nuclear data from the field of shielding. The nuclides used for shielding are numerous, and the nuclear data on these isotopes are required. Some of them cannot be ignored as the source of secondary γ-ray or in view of the radioactivation of materials. The requirements for the nuclear data of neutrons in the field of shielding are those concerning the reaction cross sections producing secondary γ-ray, the reaction cross sections including the production of secondary neutrons, elastic scattering cross sections, and total cross sections. The topics in the Paris conference about neutron shielding data are described, such as the methodology of sensitivity evaluation, the standardization of group constant libraries, the bench mark experiment on iron and sodium, and the cross section of γ-ray production. In the shielding of nuclear fission reactors, the γ-ray production owing to nuclear fission reaction is also important. In (d, t) fusion reactors, high energy neutrons are generated, and high energy γ-ray is emitted through giant E1 resonance. (Kako, I.)

  11. Radiation shield for nuclear reactors

    International Nuclear Information System (INIS)

    Weissenfluh, J.A.

    1978-01-01

    A shield for use with nuclear reactor systems to attenuate radiation resulting from reactor operation is described. The shield comprises a container preferably of a thin, flexible or elastic material, which may be in the form of a bag, a mattress, a toroidal segment or toroid or the like filled with radiation attenuating liuid. Means are provided in the container for filling and draining the container in place. Due to its flexibility, the shield readily conforms to irregularities in surfaces with which it may be in contact in a shielding position

  12. Design of radiation shields in nuclear reactor core

    International Nuclear Information System (INIS)

    Mousavi Shirazi, A.; Daneshvar, Sh.; Aghanajafi, C.; Jahanfarnia, Gh.; Rahgoshay, M.

    2008-01-01

    This article consists of designing radiation shields in the core of nuclear reactors to control and restrain the harmful nuclear radiations in the nuclear reactor cores. The radiation shields protect the loss of energy. caused by nuclear radiation in a nuclear reactor core and consequently, they cause to increase the efficiency of the reactor and decrease the risk of being under harmful radiations for the staff. In order to design these shields, by making advantages of the O ppenheim Electrical Network m ethod, the structure of the shields are physically simulated and by obtaining a special algorithm, the amount of optimized energy caused by nuclear radiations, is calculated

  13. Development of radiation shielding standards in the American Nuclear Society

    International Nuclear Information System (INIS)

    Trubey, D.K.

    1975-11-01

    The American Nuclear Society (ANS) is a standards-writing organization-member of the American National Standards Institute (ANSI). The ANS Standards Committee has a subcommittee denoted ANS-6, Shielding, whose charge is to establish standards in connection with radiation protection and shielding, to provide shielding information to other standards writing groups, and to prepare recommended sets of shielding data and test problems. This paper is a progress report of this subcommittee

  14. Radiation protection and shielding standards for the 1980s

    International Nuclear Information System (INIS)

    Trubey, D.K.

    1982-01-01

    The American Nuclear Society (ANS) is a standards-writing organization member of the American National Standards Institute (ANSI). The ANS Standards Committee has a subcommittee denoted ANS-6, Radiation Protection and Shielding, whose charge is to develop standards for radiation protection and shield design, to provide shielding information to other standards-writing groups, and to develop standard reference shielding data and test problems. This paper is a progress report of this subcommittee. Significant progress has been made since the last comprehensive report to the Society

  15. Nuclear steam generator tubesheet shield

    International Nuclear Information System (INIS)

    Nickerson, J.H.D.; Ruhe, A.

    1982-01-01

    The invention involves improvements to a nuclear steam generator of the type in which a plurality of U-shaped tubes are connected at opposite ends to a tubesheet and extend between inlet and outlet chambers, with the steam generator including an integral preheater zone adjacent to the downflow legs of the U-shaped tubes. The improvement is a thermal shield disposed adjacent to an upper face of the tubesheet within the preheater zone, the shield including ductile cladding material applied directly to the upper face of the tubesheet, with the downflow legs of the U-shaped tubes extending through the cladding into the tubesheet

  16. Assessment of radiation shielding materials for protection of space crews using CR-39 plastic nuclear track detector

    International Nuclear Information System (INIS)

    DeWitt, J.M.; Benton, E.R.; Uchihori, Y.; Yasuda, N.; Benton, E.V.; Frank, A.L.

    2009-01-01

    A significant obstacle to long duration human space exploration such as the establishment of a permanent base on the surface of the Moon or a human mission to Mars is the risk posed by prolonged exposure to space radiation. In order to keep mission costs at acceptable levels while simultaneously minimizing the risk from radiation to space crew health and safety, a judicious use of optimized shielding materials will be required. We have undertaken a comprehensive study using CR-39 plastic nuclear track detector (PNTD) to characterize the radiation shielding properties of a range of materials-both common baseline materials such as Al and polyethylene, and novel multifunctional materials such as carbon composites-at heavy ion accelerators. The study consists of analyzing CR-39 PNTD exposed in front of and behind shielding targets of varying composition and at a number of depths (target thicknesses) relevant to the development and testing of materials for space radiation shielding. Most targets consist of 10 cm x 10 cm slabs of solid materials ranging in thickness from 1 to >30 g/cm 2 . Exposures have been made to beams of C, O, Ne, Si, Ar, and Fe at energies ranging from 290 MeV/amu to 1 GeV/amu at the National Institute of Radiological Sciences HIMAC and the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory. Analysis of the exposed detectors yields LET spectrum, dose, and dose equivalent as functions of target depth and composition, and incident heavy ion charge, energy, and fluence. Efforts are currently underway to properly weigh and combine these results into a single quantitative estimate of a material's ability to shield space crews from the interplanetary galactic cosmic ray flux.

  17. Nuclear reactor neutron shielding

    Science.gov (United States)

    Speaker, Daniel P; Neeley, Gary W; Inman, James B

    2017-09-12

    A nuclear reactor includes a reactor pressure vessel and a nuclear reactor core comprising fissile material disposed in a lower portion of the reactor pressure vessel. The lower portion of the reactor pressure vessel is disposed in a reactor cavity. An annular neutron stop is located at an elevation above the uppermost elevation of the nuclear reactor core. The annular neutron stop comprises neutron absorbing material filling an annular gap between the reactor pressure vessel and the wall of the reactor cavity. The annular neutron stop may comprise an outer neutron stop ring attached to the wall of the reactor cavity, and an inner neutron stop ring attached to the reactor pressure vessel. An excore instrument guide tube penetrates through the annular neutron stop, and a neutron plug comprising neutron absorbing material is disposed in the tube at the penetration through the neutron stop.

  18. Isotope effects on nuclear shielding

    International Nuclear Information System (INIS)

    Hansen, P.E.

    1983-01-01

    This review concentrates upon empirical trends and practical uses of mostly secondary isotope effects, both of the intrinsic and equilibrium types. The text and the tables are arranged in the following fashion. The most 'popular' isotope effect is treated first, deuterium isotope effects on 13 C nuclear shielding, followed by deuterium on 1 H nuclear shieldings, etc. Focus is thus on the isotopes producing the effect rather than on the nuclei suffering the effect. After a brief treatment of each type of isotope effect, general trends are dealt with. Basic trends of intrinsic isotope effects such as additivity, solvent effects, temperature effects, steric effects, substituent effects and hyperconjugation are discussed. Uses of isotope effects for assignment purposes, in stereochemical studies, in hydrogen bonding and in isotopic tracer studies are dealt with. Kinetic studies, especially of phosphates, are frequently performed by utilizing isotope effects. In addition, equilibrium isotope effects are treated in great detail as these are felt to be new and very important and may lead to new uses of isotope effects. Techniques used to obtain isotope effects are briefly surveyed at the end of the chapter. (author)

  19. Concrete shielding for nuclear ship 'Mutsu'

    International Nuclear Information System (INIS)

    Nagase, Tetsuo; Saito, Tetsuo

    1983-01-01

    The repair works of the shielding for the nuclear ship ''Mutsu'' were completed in August, 1982. For the primary shielding, serpentine concrete was adopted as it contains a large quantity of water required for neutron shielding, and in the secondary shielding at the upper part of the reactor containment vessel, the original shielding was abolished, and the heavy concrete (high water content, high density concrete) which is effective for neutron and gamma-ray shielding was newly adopted. In this report, the design and construction using these shielding concrete are outlined. In September, 1974, Mutsu caused radiation leak during the test, and the cause was found to be the fast neutrons streaming through a gap between the reactor pressure vessel and the primary shielding. The repair works were carried out in the Sasebo Shipyard. The outline of the repair works of the shielding is described. The design condition for the shielding, the design standard for the radiation dose outside and inside the ship, the method of shielding analysis and the performance required for shielding concrete are reported. The selection of materials, the method of construction and mixing ratio, the evaluation of the soundness and properties of concrete, and the works of placing the shielding concrete are outlined. (Kako, I.)

  20. Concrete shielding for nuclear ship 'Mutsu'

    International Nuclear Information System (INIS)

    Nagase, Tetsuo; Nakajima, Tadao; Okumura, Tadahiko; Saito, Tetsuo

    1983-01-01

    The nuclear ship ''Mutsu'' was constructed in 1970 as the fourth in the world. On September 1, 1974, during the power raising test in the Pacific Ocean, radiation leak was detected. As the result of investigation, it was found that the cause was the fast neutrons streaming through the gap between the reactor pressure vessel and the primary shield. In order to repair the shielding facility, the Japan Nuclear Ship Research Development Agency carried out research and development and shielding design. It was decided to adopt serpentine concrete for the primary shield, which is the excellent moderator of fast neutrons even at high temperature, and heavy concrete for the secondary shield, which is effective for shielding both gamma ray and neutron beam. The repair of shielding was carried out in the Sasebo Shipyard, and completed in August, 1982. The outline of the repair work is reported. The weight increase was about 300 t. The conditions of the shielding design, the method of shielding analysis, the performance required for the shielding concrete, the preliminary experiment on heavy concrete and the construction works of serpentine concrete and heavy concrete are described. (Kako, I.)

  1. Improvements in or relating to nuclear shields

    International Nuclear Information System (INIS)

    Hawkins, R.J.; Riley, K.; Powell, C.

    1981-01-01

    A nuclear radiation shield comprises two pieces of steel held together edge to edge by a weld, the depth of which is less than the thickness of either of the edges. As the radiaion shielding effect of the weld will be less than the steel, an insert is bolted or welded over the weld. (U.K.)

  2. Radiation shield for nuclear reactors

    International Nuclear Information System (INIS)

    Weissenfluh, J.A.

    1980-01-01

    A reusable radiation shield for use in a reactor installation comprises a thin-walled, flexible and resilient container, made of plastic or elastomeric material, containing a hydrogenous fluid with boron compounds in solution. The container can be filled and drained in position and the fluid can be recirculated if required. When not in use the container can be folded and stored in a small space. The invention relates to a shield to span the top of the annular space between a reactor vessel and the primary shield. For this purpose a continuous toroidal container or a series of discrete segments is used. Other forms can be employed for different purposes, e.g. mattress- or blanket-like forms can be draped over potential sources of radiation or suspended from a mobile carrier and placed between a worker and a radiation source. (author)

  3. Nuclear reactor shield including magnesium oxide

    International Nuclear Information System (INIS)

    Rouse, C.A.; Simnad, M.T.

    1981-01-01

    An improvement is described for nuclear reactor shielding of a type used in reactor applications involving significant amounts of fast neutron flux. The reactor shielding includes means providing structural support, neutron moderator material, neutron absorber material and other components, wherein at least a portion of the neutron moderator material is magnesium in the form of magnesium oxide either alone or in combination with other moderator materials such as graphite and iron

  4. Shield structure for a nuclear reactor

    International Nuclear Information System (INIS)

    Rouse, C.A.; Simnad, M.T.

    1979-01-01

    An improved nuclear reactor shield structure is described for use where there are significant amounts of fast neutron flux above an energy level of approximately 70 keV. The shield includes structural supports and neutron moderator and absorber systems. A portion at least of the neutron moderator material is magnesium oxide either alone or in combination with other moderator materials such as graphite and iron. (U.K.)

  5. Nuclear power plant component protection

    International Nuclear Information System (INIS)

    Michel, E.; Ruf, R.; Dorner, H.

    1976-01-01

    Described is a nuclear power plant installation which includes a concrete biological shield forming a pit in which a reactor pressure vessel is positioned. A steam generator on the outside of the shield is connected with the pressure vessel via coolant pipe lines which extend through the shield, the coolant circulation being provided by a coolant pump which is also on the outside of the shield. To protect these components on the outside of the shield and which are of mainly or substantially cylindrical shape, semicylindrical concrete segments are interfitted around them to form complete outer cylinders which are retained against outward separation radially from the components, by rings of high tensile steel which may be interspaced so closely that they provide, in effect, an outer steel cylinder. The invention is particularly applicable to pressurized-water coolant reactor installations

  6. Radiation protection/shield design: a need for a systems approach

    International Nuclear Information System (INIS)

    Disney, R.K.

    1977-01-01

    Radiation protection/shielding design of a nuclear facility requires a coordinated effort of many engineering disciplines to meet the requirements imposed by regulations. The system approach to Clinch River Breeder Reactor Plant (CRBRP) radiation protection is described, and the program developed to implement this approach is defined. In addition, the principal shielding design problems for LMFBR nuclear reactor systems are discussed in relation to LWR nuclear reactor system shielding designs. The methodology used to analyze these problems in the U.S. LMFBR program, the resultant design solutions, and the experimental verification of these designs and/or methods are discussed

  7. Shielded chamber control stations: an answer to radiological protection requirements

    International Nuclear Information System (INIS)

    Delaboudiniere, Catherine.

    1979-06-01

    This study, carried out at the radiometallurgy laboratory of the Fontenay-aux-Roses Nuclear Research Centre, is based on an ergonomic approach. It shows that the shielded chamber control station, designed for human protection against ionizing radiations, demands an effort of adaptation on the part of the operator. This station does in fact meet radiological protection obligations but would benefit from certain improvements aimed at reducing the secondary fatigue of manipulators already under the strain of adapting to the machine. Fields in which improvements and/or changes are desirable have been investigated with special reference to telemanipulators. New and better designed instruments will soon appear on the telemanipulator market [fr

  8. Summary of Prometheus Radiation Shielding Nuclear Design Analyses , for information

    International Nuclear Information System (INIS)

    J. Stephens

    2006-01-01

    This report transmits a summary of radiation shielding nuclear design studies performed to support the Prometheus project. Together, the enclosures and references associated with this document describe NRPCT (KAPL and Bettis) shielding nuclear design analyses done for the project

  9. Nuclear data requirements for fusion reactor shielding

    International Nuclear Information System (INIS)

    Abdou, M.A.

    1979-01-01

    The nuclear data requirements for experimental, demonstration and commercial fusion reactors are reviewed. Particular emphasis is given to the shield as well as major reactor components of concern to the nuclear performance. The nuclear data requirements are defined as a result of analyzing four key areas. These are the most likely candidate materials, energy range, types of needed nuclear data, and the required accuracy in the data. Deducing the latter from the target goals for the accuracy in prediction is also discussed. A specific proposal of measurements is recommended. Priorities for acquisition of data are also assigned. (author)

  10. Nuclear reactor cavity streaming shield

    International Nuclear Information System (INIS)

    Klotz, R.J.; Stephen, D.W.

    1978-01-01

    The upper portion of a nuclear reactor vessel supported in a concrete reactor cavity has a structure mounted below the top of the vessel between the outer vessel wall and the reactor cavity wall which contains hydrogenous material which will attenuate radiation streaming upward between vessel and the reactor cavity wall while preventing pressure buildup during a loss of coolant accident

  11. A superconducting shield to protect astronauts

    CERN Document Server

    Antonella Del Rosso

    2015-01-01

    The CERN Superconductors team in the Technology department is involved in the European Space Radiation Superconducting Shield (SR2S) project, which aims to demonstrate the feasibility of using superconducting magnetic shielding technology to protect astronauts from cosmic radiation in the space environment. The material that will be used in the superconductor coils on which the project is working is magnesium diboride (MgB2), the same type of conductor developed in the form of wire for CERN for the LHC High Luminosity Cold Powering project.   Image: K. Anthony/CERN. Back in April 2014, the CERN Superconductors team announced a world-record current in an electrical transmission line using cables made of the MgB2 superconductor. This result proved that the technology could be used in the form of wire and could be a viable solution for both electrical transmission for accelerator technology and long-distance power transportation. Now, the MgB2 superconductor has found another application: it wi...

  12. Radiation protection in nuclear medicine

    International Nuclear Information System (INIS)

    Seeburrun, V.

    2013-04-01

    Radiation protection in nuclear medicine in this project is concerned with the reduction of doses to workers, patients and members of the public. Protection of workers is achieved by adopting good personal habits, good housekeeping, proper use of personal protective devices and equipment, attend training and have continuous education. Exposure to radiation of workers and the members of the public are minimised by proper management of radioactive waste and safe transport of radioactive material. The design and shielding of a nuclear medicine department shall further provide for the protection of the worker, the patient and the general public. Protection of patient is achieved by justifying the procedure, delivering the minimum radiation dose possible to the patient while obtaining the best image quality and applying guidance levels. Special considerations shall be given to pregnant and breast-feeding patients. Quality assurance programme through image quality, radiopharmaceutical quality and patient records on nuclear medicine procedures shall provide assurance to the patient. (au)

  13. Methodology of shielding calculation for nuclear reactors

    International Nuclear Information System (INIS)

    Maiorino, J.R.; Mendonca, A.G.; Otto, A.C.; Yamaguchi, Mitsuo

    1982-01-01

    A methodology of calculation that coupling a serie of computer codes in a net that make the possibility to calculate the radiation, neutron and gamma transport, is described, for deep penetration problems, typical of nuclear reactor shielding. This net of calculation begining with the generation of constant multigroups, for neutrons and gamma, by the AMPX system, coupled to ENDF/B-IV data library, the transport calculation of these radiations by ANISN, DOT 3.5 and Morse computer codes, up to the calculation of absorbed doses and/or equivalents buy SPACETRAN code. As examples of the calculation method, results from benchmark n 0 6 of Shielding Benchmark Problems - ORNL - RSIC - 25, namely Neutron and Secondary Gamma Ray fluence transmitted through a Slab of Borated Polyethylene, are presented. (Author) [pt

  14. Technical products for radiation shielding. Shield assembled from lead blocks for radiation protection. General technical requirements

    International Nuclear Information System (INIS)

    1981-01-01

    The object of this standard description is the general technological requirements of 50 and 100 mm thick radiation protection shields assembled from lead blocks. The standard contains the definitions, types, parameters and dimensions of shields, their technical and acceptance criteria with testing methods, tagging, packaging, transportation and storage requirements, producer's liability. Some illustrated assembling examples, preferred parameters and dosimetry methods for shield inspection are given. (R.P.)

  15. Radiation protection and shielding design - Strengthening the link

    International Nuclear Information System (INIS)

    Hobson, J.; Cooper, A.

    2005-01-01

    The improvement in quality and flexibility of shielding methods and data has been progressive and beneficial in opening up new opportunities for optimising radiation protection in design. The paper describes how these opportunities can best be seized by taking a holistic view of radiation protection, with shielding design being an important component part. This view is best achieved by enhancing the role of 'shielding assessors' so that they truly become 'radiation protection designers'. The increase in speed and efficiency of shielding calculations has been enormous over the past decades. This has raised the issue of how the assessor's time now can be best utilised; pursuing ever greater precision and accuracy in shielding/dose assessments, or improving the contribution that shielding assessment makes to radiological protection and cost-effective design. It is argued in this paper that the latter option is of great importance and will give considerable benefits. Shielding design needs to form part of a larger radiation protection perspective based on a deep understanding/appreciation of the opportunities and constraints of operators and designers, enabling minimal design iterations, cost optimisation of alternative designs (with a 'lifetime' perspective) and improved realisation of design intent in operations. The future of shielding design development is argued to be not in improving the 'tool-kit', but in enhanced understanding of the 'product' and the 'process' for achieving it. The holistic processes being developed in BNFL to realise these benefits are described in the paper and will be illustrated by case studies. (authors)

  16. Master Training in Radiological Protection Facilities Radioactive and Nuclear

    International Nuclear Information System (INIS)

    Verdu, G.; Mayo, P.; Campayo, J. M.

    2011-01-01

    The master includes general aspects of radiation protection in nuclear facilities. also an advanced module to acquire a high level training highlights as nuclear decommissioning, shielding calculation using advanced codes, particle accelerators, international law, etc.

  17. Radiation shielding activities at the OECD/Nuclear Energy Agency

    International Nuclear Information System (INIS)

    Sartori, Enrico; Vaz, Pedro

    2000-01-01

    The OECD Nuclear Energy Agency (NEA) has devoted considerable effort over the years to radiation shielding issues. The issues are addressed through international working groups. These activities are carried out in close co-ordination and co-operation with the Radiation Safety Information Computational Center (RSICC). The areas of work include: basic nuclear data activities in support of radiation shielding, computer codes, shipping cask shielding applications, reactor pressure vessel dosimetry, shielding experiments database. The method of work includes organising international code comparison exercises and benchmark studies. Training courses on radiation shielding computer codes are organised regularly including hands-on experience in modelling skills. The scope of the activity covers mainly reactor shields and spent fuel transportation packages, but also fusion neutronics and in particular shielding of accelerators and irradiation facilities. (author)

  18. Shield design development of nuclear propulsion merchant ship

    International Nuclear Information System (INIS)

    Tanaka, Yoshihisa

    1975-01-01

    Shielding design both in Japan and abroad for nuclear propulsion merchant ships is explained, with emphasis on the various technological problems having occurred in the shield design for one-body type and separate type LWRs as conceptual design. The following matters are described: the peculiarities of the design as compared with the case of land-based nuclear reactors, problems in the design standards of shielding, the present status and development of the design methods, and the instances of the design; thereby, the trends of shielding design are disclosed. The following matters are pointed out: Importance of the optimum design, of shielding, significance of radiation streaming through large voids, activation of the secondary water in built-in type steam generators, and the need of the guides for shield design. (Mori, K.)

  19. Privacy protected text analysis in DataSHIELD

    Directory of Open Access Journals (Sweden)

    Rebecca Wilson

    2017-04-01

    Whilst it is possible to analyse free text within a DataSHIELD infrastructure, the challenge is creating generalised and resilient anti-disclosure methods for free text analysis. There are a range of biomedical and health sciences applications for DataSHIELD methods of privacy protected analysis of free text including analysis of electronic health records and analysis of qualitative data e.g. from social media.

  20. Shielding estimation for nuclear medicine therapy ward: our experience

    International Nuclear Information System (INIS)

    Skopljak-Beganovic, A.; Kucukalic-Selimovic, E.; Beganovic, A.; Drljevic, A.

    2008-01-01

    Full text: The aim of this study was to calculate and estimate the shielding thickness for a new Nuclear Medicine Therapy Ward. Parameters available for shielding calculation were: ground plan of the ward, radionuclides planned for use, maximum administered activity of I-131, maximum delivered activity of I-131 to the ward per week, average time spent in the hospital after the treatment. The most hazardous and most commonly used radioisotope is I-131. The target dose that needs to be met for occupationally exposed workers is 0.3 mSv per year. There are several factors that could be changed in order to achieve this value: distance from the source, shielding thickness, angle of incidence, occupational and usage factors. The maximum dose rate at 1 meter from the thyroid gland of the patient was considered to be 100 mSv/h. The distances and incidence angles could not be changed since these vales were predetermined in the ground plan. Different usage and occupational factors were used for different rooms in the ward. We used occupational factor 1 for the bed and 1/6 for the bathroom, and usage factor 1 for nurses' room and patient room and 1/6 for the corridors, etc. The easiest way of calculating dose attenuation in material was by introducing the HVL and TVL for broad beams. TVL and HVL were taken from the graph.The results show that shielding thickness should be in the range of 3 mmPb for room doors to 30 mmPb for the wall adjacent to the nurse's office. Most of the walls are 20 mmPb thick. These values were calculated using conservative assumptions and are more then enough to protect staff, patients and public from external radiation. If the construction cannot support the weight of lead some rearrangements regarding patient positions could be made. (author)

  1. Evaluation of ilmenite serpentine concrete and ordinary concrete as nuclear reactor shielding

    International Nuclear Information System (INIS)

    Abulfaraj, W.H.; Kamal, S.M.

    1994-01-01

    The present study involves adapting a formal decision methodology to the selection of alternative nuclear reactor concrete shielding. Multiattribute utility theory is selected to accommodate decision maker's preferences. Multiattribute utility theory (MAU) is here employed to evaluate two appropriate nuclear reactor shielding concretes in terms of effectiveness to determine the optimal choice in order to meet the radiation protection regulations. These concretes are Ordinary concrete (O.C.) and Illmenite Serpentile concrete (I.S.C.). These are normal weight concrete and heavy weight heat resistive concrete, respectively. The effectiveness objective of the nuclear reactor shielding is defined and structured into definite attributes and subattributes to evaluate the best alternative. Factors affecting the decision are dose received by reactor's workers, the material properties as well as cost of concrete shield. A computer program is employed to assist in performing utility analysis. Based upon data, the result shows the superiority of Ordinary concrete over Illmenite Serpentine concrete. (Author)

  2. Experimental shielding evaluation of the radiation protection provided by the structurally significant components of residential structures.

    Science.gov (United States)

    Dickson, E D; Hamby, D M

    2014-03-01

    The human health and environmental effects following a postulated accidental release of radioactive material to the environment have been a public and regulatory concern since the early development of nuclear technology. These postulated releases have been researched extensively to better understand the potential risks for accident mitigation and emergency planning purposes. The objective of this investigation is to provide an updated technical basis for contemporary building shielding factors for the US housing stock. Building shielding factors quantify the protection from ionising radiation provided by a certain building type. Much of the current data used to determine the quality of shielding around nuclear facilities and urban environments is based on simplistic point-kernel calculations for 1950s era suburbia and is no longer applicable to the densely populated urban environments realised today. To analyse a building's radiation shielding properties, the ideal approach would be to subject a variety of building types to various radioactive sources and measure the radiation levels in and around the building. While this is not entirely practicable, this research analyses the shielding effectiveness of ten structurally significant US housing-stock models (walls and roofs) important for shielding against ionising radiation. The experimental data are used to benchmark computational models to calculate the shielding effectiveness of various building configurations under investigation from two types of realistic environmental source terms. Various combinations of these ten shielding models can be used to develop full-scale computational housing-unit models for building shielding factor calculations representing 69.6 million housing units (61.3%) in the United States. Results produced in this investigation provide a comparison between theory and experiment behind building shielding factor methodology.

  3. Experimental shielding evaluation of the radiation protection provided by the structurally significant components of residential structures

    International Nuclear Information System (INIS)

    Dickson, E D; Hamby, D M

    2014-01-01

    The human health and environmental effects following a postulated accidental release of radioactive material to the environment have been a public and regulatory concern since the early development of nuclear technology. These postulated releases have been researched extensively to better understand the potential risks for accident mitigation and emergency planning purposes. The objective of this investigation is to provide an updated technical basis for contemporary building shielding factors for the US housing stock. Building shielding factors quantify the protection from ionising radiation provided by a certain building type. Much of the current data used to determine the quality of shielding around nuclear facilities and urban environments is based on simplistic point-kernel calculations for 1950s era suburbia and is no longer applicable to the densely populated urban environments realised today. To analyse a building’s radiation shielding properties, the ideal approach would be to subject a variety of building types to various radioactive sources and measure the radiation levels in and around the building. While this is not entirely practicable, this research analyses the shielding effectiveness of ten structurally significant US housing-stock models (walls and roofs) important for shielding against ionising radiation. The experimental data are used to benchmark computational models to calculate the shielding effectiveness of various building configurations under investigation from two types of realistic environmental source terms. Various combinations of these ten shielding models can be used to develop full-scale computational housing-unit models for building shielding factor calculations representing 69.6 million housing units (61.3%) in the United States. Results produced in this investigation provide a comparison between theory and experiment behind building shielding factor methodology. (paper)

  4. MFTF-α+T end cell vacuum vessel and nuclear shield trade studies

    International Nuclear Information System (INIS)

    Kirchner, J.

    1984-01-01

    Three separate and distinct vacuum vessel and nuclear shield trade studies were performed in series. The studies are: vacuum topology, nuclear shield location and composition, and water bulk shield location and material selection

  5. Study and installation of concrete shielding in the civil engineering of nuclear construction (1960); Etude et mise en place des betons de protection dans le genie civil des ouvrages nucleaires (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, F [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    The object of this report is to give technical information about high density concretes which have become very important for radiation biological shielding. The most generally used heavy aggregates (barytes, ilmenite, ferrophosphorus, limonite, magnetite and iron punching) to make these concretes are investigated from the point of view prospecting and physical and chemical characteristics. At first, a general survey of shielding concretes is made involving the study of components, mixing and placing methods, then, a detailed investigation of some high density concretes: barytes concrete, with incorporation of iron punching or iron shot, ferrophosphorus concrete, ilmenite concrete and magnetite concrete, more particularly with regard to grading and mix proportions and testing process. To put this survey in concrete form, two practical designs are described such as they have been carried out at the Saclay Nuclear Station. Specifications are given for diverse concretes and for making the proton-synchrotron 'Saturne' shielding blocks. (author) [French] Ce rapport a pour objet de donner des precisions techniques au sujet des betons a haute densite qui ont pris une grande importance pour la protection biologique contre les rayonnements. Les agregats lourds les plus couramment utilises (barytine, ilmenite, ferrophosphore, limonite, magnetite et riblons) pour la fabrication de ces betons, sont examines du point de vue prospection et caracteristiques physiques et chimiques. On procede d'abord a une etude generale des betons de protection comprenant l'etude des constituants, de la confection et de la mise en place, ensuite, a un examen detaille de quelques betons a haute densite: betons a base de barytine, avec incorporation de riblons ou de grenaille de fonte, betons au ferrophosphore, a base d'ilmenite ou de magnetite, notamment en ce qui concerne la granulometrie, la composition, le dosage et les processus d'essais. Pour concretiser ces etudes, deux applications pratiques

  6. Study and installation of concrete shielding in the civil engineering of nuclear construction (1960); Etude et mise en place des betons de protection dans le genie civil des ouvrages nucleaires (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, F. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    The object of this report is to give technical information about high density concretes which have become very important for radiation biological shielding. The most generally used heavy aggregates (barytes, ilmenite, ferrophosphorus, limonite, magnetite and iron punching) to make these concretes are investigated from the point of view prospecting and physical and chemical characteristics. At first, a general survey of shielding concretes is made involving the study of components, mixing and placing methods, then, a detailed investigation of some high density concretes: barytes concrete, with incorporation of iron punching or iron shot, ferrophosphorus concrete, ilmenite concrete and magnetite concrete, more particularly with regard to grading and mix proportions and testing process. To put this survey in concrete form, two practical designs are described such as they have been carried out at the Saclay Nuclear Station. Specifications are given for diverse concretes and for making the proton-synchrotron 'Saturne' shielding blocks. (author) [French] Ce rapport a pour objet de donner des precisions techniques au sujet des betons a haute densite qui ont pris une grande importance pour la protection biologique contre les rayonnements. Les agregats lourds les plus couramment utilises (barytine, ilmenite, ferrophosphore, limonite, magnetite et riblons) pour la fabrication de ces betons, sont examines du point de vue prospection et caracteristiques physiques et chimiques. On procede d'abord a une etude generale des betons de protection comprenant l'etude des constituants, de la confection et de la mise en place, ensuite, a un examen detaille de quelques betons a haute densite: betons a base de barytine, avec incorporation de riblons ou de grenaille de fonte, betons au ferrophosphore, a base d'ilmenite ou de magnetite, notamment en ce qui concerne la granulometrie, la composition, le dosage et les processus d'essais. Pour concretiser ces

  7. SU-F-I-71: Fetal Protection During Fluoroscopy: To Shield Or Not to Shield?

    International Nuclear Information System (INIS)

    Joshi, S; Vanderhoek, M

    2016-01-01

    Purpose: Lead aprons are routinely used to shield the fetus from radiation during fluoroscopically guided interventions (FGI) involving pregnant patients. When placed in the primary beam, lead aprons often reduce image quality and increase fluoroscopic radiation output, which can adversely affect fetal dose. The purpose of this work is to identify an effective and practical method to reduce fetal dose without affecting image quality. Methods: A pregnant patient equivalent abdominal phantom is set on the table along with an image quality test object (CIRS model 903) representing patient anatomy of interest. An ion chamber is positioned at the x-ray beam entrance to the phantom, which is used to estimate the relative fetal dose. For three protective methods, image quality and fetal dose measurements are compared to baseline (no protection):1. Lead apron shielding the entire abdomen; 2. Lead apron shielding part of the abdomen, including the fetus; 3. Narrow collimation such that fetus is excluded from the primary beam. Results: With lead shielding the entire abdomen, the dose is reduced by 80% relative to baseline along with a drastic deterioration of image quality. With lead shielding only the fetus, the dose is reduced by 65% along with complete preservation of image quality, since the image quality test object is not shielded. However, narrow collimation results in 90% dose reduction and a slight improvement of image quality relative to baseline. Conclusion: The use of narrow collimation to protect the fetus during FGI is a simple and highly effective method that simultaneously reduces fetal dose and maintains sufficient image quality. Lead aprons are not as effective at fetal dose reduction, and if placed improperly, they can severely degrade image quality. Future work aims to investigate a wider variety of fluoroscopy systems to confirm these results across many different system geometries.

  8. SU-F-I-71: Fetal Protection During Fluoroscopy: To Shield Or Not to Shield?

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, S; Vanderhoek, M [Henry Ford Health System, Detroit, MI (United States)

    2016-06-15

    Purpose: Lead aprons are routinely used to shield the fetus from radiation during fluoroscopically guided interventions (FGI) involving pregnant patients. When placed in the primary beam, lead aprons often reduce image quality and increase fluoroscopic radiation output, which can adversely affect fetal dose. The purpose of this work is to identify an effective and practical method to reduce fetal dose without affecting image quality. Methods: A pregnant patient equivalent abdominal phantom is set on the table along with an image quality test object (CIRS model 903) representing patient anatomy of interest. An ion chamber is positioned at the x-ray beam entrance to the phantom, which is used to estimate the relative fetal dose. For three protective methods, image quality and fetal dose measurements are compared to baseline (no protection):1. Lead apron shielding the entire abdomen; 2. Lead apron shielding part of the abdomen, including the fetus; 3. Narrow collimation such that fetus is excluded from the primary beam. Results: With lead shielding the entire abdomen, the dose is reduced by 80% relative to baseline along with a drastic deterioration of image quality. With lead shielding only the fetus, the dose is reduced by 65% along with complete preservation of image quality, since the image quality test object is not shielded. However, narrow collimation results in 90% dose reduction and a slight improvement of image quality relative to baseline. Conclusion: The use of narrow collimation to protect the fetus during FGI is a simple and highly effective method that simultaneously reduces fetal dose and maintains sufficient image quality. Lead aprons are not as effective at fetal dose reduction, and if placed improperly, they can severely degrade image quality. Future work aims to investigate a wider variety of fluoroscopy systems to confirm these results across many different system geometries.

  9. Protecting sources: from shield laws to Wikileaks

    Directory of Open Access Journals (Sweden)

    Mélanie Dupéré

    2015-09-01

    Full Text Available This paper focuses on recent developments in the right and ability of journalists to protect their sources’ anonymity in the United Kingdom, particularly in light of the Snowden revelations of June 2013, and the significance of collaboration between the global online media organization Wikileaks and mainstream news organisations. It explores two key difficulties faced by journalists: the notion of a qualified professional privilege and the unknown extent of covert requests by public authorities for disclosure involving communications data and metadata. In doing so, it comments upon the opening filled by Wikileaks, which protects its sources’ anonymity through high data security and encryption. This paper’s findings tend to show that the covert practice of blanket mass digital surveillance of individual communications including journalists’ is undermining source protection and the rise of Wikileaks as an alternative model is challenging the traditional role of journalists as mediators and gatekeepers in the digital era.

  10. Nuclear accidents and protection

    International Nuclear Information System (INIS)

    Biocanin, R.; Amidzic, B.

    2005-01-01

    The numerous threats are our cruel reality. There is a great arsenal of nuclear weapons. Nuclear terrorism and nuclear accidents are always possible, especially during the transport and handling different nuclear material. Terrorist organisation also goes for coming into the possession of the nuclear means. Specific and important problem is human radioactive contamination in using nuclear energy for peaceful and military purpose. So, realisation of the universal and united system of NBCD gives us a possibility by using the modern communication equipment and very effective mobile units to react in a real time and successfully perform monitoring, alarming, protection and decontamination. (author) [sr

  11. Analysis of shield for the nuclear ship MUTSU

    International Nuclear Information System (INIS)

    Fuse, Takayoshi; Takeuchi, Kiyoshi; Yamaji, Akio

    1975-01-01

    On the nuclear ship MUTSU, a higher-than-expected level of radiation was found, with output raised to 1.4 per cent. To investigate the radiation leakage, the analysis of the shielding problem utilized a four-step sequence of PALLAS-2DCY cylindrical r-z calculations with fixed sources distributions in the core. The neutron dose contours show the importance of streaming in the gap between the reactor vessel and the primary shield. Dominant consideration of thermal insulation exclude shielding from this area resulting in an imbalance in the shielding effectiveness. The neutron dose rate at the upper part of the reactor vessel is increased by neutrons incident on the head from cavity scattering. The calculation indicates that the neutron dose rate at the top of the primary shield is 5 rem/hr at 100 per cent output. (auth.)

  12. QED Theory of the Nuclear Magnetic Shielding in Hydrogenlike Ions

    International Nuclear Information System (INIS)

    Yerokhin, V. A.; Pachucki, K.; Harman, Z.; Keitel, C. H.

    2011-01-01

    The shielding of the nuclear magnetic moment by the bound electron in hydrogenlike ions is calculated ab initio with inclusion of relativistic, nuclear, and quantum electrodynamics (QED) effects. The QED correction is evaluated to all orders in the nuclear binding strength parameter and, independently, to the first order in the expansion in this parameter. The results obtained lay the basis for the high-precision determination of nuclear magnetic dipole moments from measurements of the g factor of hydrogenlike ions.

  13. Space nuclear reactor shields for manned and unmanned applications

    International Nuclear Information System (INIS)

    McKissock, B.I.; Bloomfield, H.S.

    1990-01-01

    Missions which use nuclear reactor power systems require radiation shielding of payload and/or crew areas to predetermined dose rates. Since shielding can become a significant fraction of the total mass of the system, it is of interest to show the effect of various parameters on shield thickness and mass for manned and unmanned applications. Algorithms were developed to give the thicknesses needed if reactor thermal power, separation distances and dose rates are given as input. The thickness algorithms were combined with models for four different shield geometries to allow tradeoff studies of shield volume and mass for a variety of manned and unmanned missions. The shield design tradeoffs presented in this study include the effects of: higher allowable dose rates; radiation hardened electronics; shorter crew exposure times; shield geometry; distance of the payload and/or crew from the reactor; and changes in the size of the shielded area. Specific NASA missions that were considered in this study include unmanned outer planetary exploration, manned advanced/evolutionary space station and advanced manned lunar base. (author)

  14. Space nuclear reactor shields for manned and unmanned applications

    International Nuclear Information System (INIS)

    Mckissock, B.I.; Bloomfield, H.S.

    1989-01-01

    Missions which use nuclear reactor power systems require radiation shielding of payload and/or crew areas to predetermined dose rates. Since shielding can become a significant fraction of the total mass of the system, it is of interest to show the effect of various parameters on shield thickness and mass for manned and unmanned applications. Algorithms were developed to give the thicknesses needed if reactor thermal power, separation distances, and dose rates are given as input. The thickness algorithms were combined with models for four different shield geometries to allow tradeoff studies of shield volume and mass for a variety of manned and unmanned missions. Shield design tradeoffs presented in this study include the effects of: higher allowable dose rates; radiation hardened electronics; shorter crew exposure times; shield geometry; distance of the payload and/or crew from the reactor; and changes in the size of the shielded area. Specific NASA missions that were considered in this study include unmanned outer planetary exploration, manned advanced/evolutionary space station, and advanced manned lunar base

  15. Investigation and assessment of lead slag concrete as nuclear shields

    International Nuclear Information System (INIS)

    Zaghloul, Y.R.

    2009-01-01

    The present work is concerned with the efficiency of heavy weight concrete as a shielding material in constructing nuclear installations as well as for radioactive wastes disposal facilities.In this context, lead slag was used as a replacement for fine aggregates in heavy concrete shields that include local heavy weight aggregates (namely; barite and ilmenite) as well as normal concrete includes dolomite and sand as coarse and fine aggregates, as a reference. The effect of different percentages of lead slag was investigated to assess the produced lead slag concrete as a nuclear shielding material. The different properties (physical, mechanical and nuclear) of the produced lead slag concrete were investigated. The results obtained showed that increasing the lead slag percentage improving the investigated properties of the different concrete mixes. In addition, ilmenite concrete with 20% lead slag showed the best results for all the investigated properties.

  16. Nuclear shielding of openings in ITER Tokamak building

    Energy Technology Data Exchange (ETDEWEB)

    Dammann, A., E-mail: alexis.dammann@iter.org [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Arumugam, A.P.; Beaudoin, V.; Beltran, D.; Benchikhoune, M.; Berruyer, F.; Cortes, P.; Gandini, F. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Ghirelli, N. [ASSYSTEM E.O.S, ZAC Saint Martin, 23, rue Benjamin Franklin, 84120 Pertuis (France); Gray, A.; Hurzlmeier, H.; Le Page, M. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Lemée, A. [SOGETI High Tech, 180 Rue René Descartes, 13851 Aix en Provence (France); Lentini, G.; Loughlin, M.; Mita, Y.; Patisson, L.; Rigoni, G.; Rathi, D.; Song, I. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)

    2013-10-15

    Highlights: ► Establishment of a methodology to design shielded opening in external wall of the Tokamak building. ► Analysis of the shielding requirement, case by case, depending on the localization and the context. ► Implementation of an integrated solution for shielded opening. -- Abstract: The external walls of the Tokamak building, made of thick concrete, provide the nuclear shielding for operators working in adjacent buildings and for the environment. There are a series of openings to these external walls, devoted to ducts or pipes for ventilation, waveguides and transmission lines for heating systems and diagnostics, cooling pipes, cable trays or busbars. The shielding properties of the wall shall be preserved by adequate design of the openings in order not to affect the radiological zoning in adjacent areas. For some of them, shielding properties of the wall are not affected because the size of the network is quite small or the source is far from the opening. But for most of the openings, specific features shall be considered. Even if the approach is the same and the ways to shield can be standardized, specific analysis is requested in any case because the constraints are different.

  17. Evaluation of X-ray shielding performance of protective aprons

    International Nuclear Information System (INIS)

    Kumagai, Michitomo; Shintani, Mitsuo; Kuranishi, Makoto

    1999-01-01

    Lead equivalent, which offers protection against x-rays, is rated with a 100 kV tube voltage in Japanese Industrial Standard (JIS) Z 4501-1988, Testing method of lead equivalent for x-ray protective devices.'' However, the actual tube voltage in general diagnostic examinations (normal to special radiography; including computed tomography, CT) is 50 to 150 kV. Therefore, we measured whether the performance of current lead aprons (three products) and protective aprons using composite materials (two products) changes at 60 to 141 kV of tube voltage. Furthermore, we evaluated x-ray shielding performance by measuring the transmission ratio of scattered x-rays. The lead equivalent of two currently used lead aprons was almost the same at all voltages. However, in one currently used lead apron and both protective aprons made of composite materials, lead equivalent decreased rapidly when tube voltage exceeded 100 kV. The transmission ratio of scattered x-rays increased with increasing tube voltage in all of the protective aprons examined. Further, in all aprons examined, the transmission ratio of scattered x-rays declined with widening of the scatter angle. As mentioned above, the x-ray shielding performance of some x-ray protective aprons suddenly decreased at tube voltages over 100 kV. Thus the performance of x-ray protective aprons should be published, and JIS Z 4501 needs to be revised. (author)

  18. Evaluation of X-ray shielding performance of protective aprons

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Michitomo; Shintani, Mitsuo; Kuranishi, Makoto [Toyama Medical and Pharmaceutical Univ. (Japan). Hospital

    1999-04-01

    Lead equivalent, which offers protection against x-rays, is rated with a 100 kV tube voltage in Japanese Industrial Standard (JIS) Z 4501-1988, Testing method of lead equivalent for x-ray protective devices.`` However, the actual tube voltage in general diagnostic examinations (normal to special radiography; including computed tomography, CT) is 50 to 150 kV. Therefore, we measured whether the performance of current lead aprons (three products) and protective aprons using composite materials (two products) changes at 60 to 141 kV of tube voltage. Furthermore, we evaluated x-ray shielding performance by measuring the transmission ratio of scattered x-rays. The lead equivalent of two currently used lead aprons was almost the same at all voltages. However, in one currently used lead apron and both protective aprons made of composite materials, lead equivalent decreased rapidly when tube voltage exceeded 100 kV. The transmission ratio of scattered x-rays increased with increasing tube voltage in all of the protective aprons examined. Further, in all aprons examined, the transmission ratio of scattered x-rays declined with widening of the scatter angle. As mentioned above, the x-ray shielding performance of some x-ray protective aprons suddenly decreased at tube voltages over 100 kV. Thus the performance of x-ray protective aprons should be published, and JIS Z 4501 needs to be revised. (author)

  19. Evaluation of radiation shielding rate of lead aprons in nuclear medicine

    International Nuclear Information System (INIS)

    Han, Sang Hyun; Han, Beom Heui; Lee, Sang Ho; Hong, Dong Heui; Kim, Gi Jin

    2017-01-01

    Considering that the X-ray apron used in the department of radiology is also used in the department of nuclear medicine, the study aimed to analyze the shielding rate of the apron according to types of radioisotopes, thus γ ray energy, to investigate the protective effects. The radioisotopes used in the experiment were the top 5 nuclides in usage statistics "9"9"mTc, "1"8F, "1"3"1I, "1"2"3I, and "2"0"1Tl, and the aprons were lead equivalent 0.35 mmPb aprons currently under use in the department of nuclear medicine. As a result of experiments, average shielding rates of aprons were "9"9"mTc 31.59%, "2"0"1Tl 68.42%, and "1"2"3I 76.63%. When using an apron, the shielding rate of "1"3'1I actually resulted in average dose rate increase of 33.72%, and "1"8F showed an average shielding rate of –0.315%, showing there was almost no shielding effect. As a result, the radioisotopes with higher shielding rate of apron was in the descending order of "1"2"3I, "2"0"1Tl, "9"9"mTc, "1"8F, "1"3"1I. Currently, aprons used in the nuclear medicine laboratory are general X-ray aprons, and it is thought that it is not appropriate for nuclear medicine environment that utilizes γ rays. Therefore, development of nuclear medicine exclusive aprons suitable for the characteristics of radioisotopes is required in consideration of effective radiation protection and work efficiency of radiation workers

  20. Evaluation of radiation shielding rate of lead aprons in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sang Hyun; Han, Beom Heui; Lee, Sang Ho [Dept. of Radiological Science, Seonam University, Asan (Korea, Republic of); Hong, Dong Heui [Dept. of Radiological Science, Far East University, Eumseong (Korea, Republic of); Kim, Gi Jin [Dept. of Nuclear Medicine, Konyang University Hospital, Daejeon (Korea, Republic of)

    2017-03-15

    Considering that the X-ray apron used in the department of radiology is also used in the department of nuclear medicine, the study aimed to analyze the shielding rate of the apron according to types of radioisotopes, thus γ ray energy, to investigate the protective effects. The radioisotopes used in the experiment were the top 5 nuclides in usage statistics {sup 99m}Tc, {sup 18}F, {sup 131}I, {sup 123}I, and {sup 201}Tl, and the aprons were lead equivalent 0.35 mmPb aprons currently under use in the department of nuclear medicine. As a result of experiments, average shielding rates of aprons were {sup 99m}Tc 31.59%, {sup 201}Tl 68.42%, and {sup 123}I 76.63%. When using an apron, the shielding rate of {sup 13}'1I actually resulted in average dose rate increase of 33.72%, and {sup 18}F showed an average shielding rate of –0.315%, showing there was almost no shielding effect. As a result, the radioisotopes with higher shielding rate of apron was in the descending order of {sup 123}I, {sup 201}Tl, {sup 99m}Tc, {sup 18}F, {sup 131}I. Currently, aprons used in the nuclear medicine laboratory are general X-ray aprons, and it is thought that it is not appropriate for nuclear medicine environment that utilizes γ rays. Therefore, development of nuclear medicine exclusive aprons suitable for the characteristics of radioisotopes is required in consideration of effective radiation protection and work efficiency of radiation workers.

  1. Heavy density concrete for nuclear radiation shielding and power stations: [Part]2

    International Nuclear Information System (INIS)

    Singha Roy, P.K.

    1987-01-01

    This article is the second part of the paper entitled 'Heavy density concrete for nuclear radiation shielding and power stations'. In this part, some of the important properties of heavy density concrete are discussed. They include density, water retentivity, air content, permeability with special reference to concrete mixes used in India's nuclear power reactors. All these properties are affected to various extents by heating. Indian shield concrete is rarely subjected to temperatures above 60degC during its life, because of thermal shield protection. During placement, the maximum anticipated rise in temperature due to heat of hydration is restricted to around 45degC by chilling, if necessary to reduce shrinkage stresses and cracks. (M.G.B.)

  2. Shielding behavior of multi-transformation phase change materials (MTPCM) against nuclear radiations

    International Nuclear Information System (INIS)

    Kumar, Ravindra; Goplani, Deepak; Kumar, Rohitash; Das, Mrinal Kumar; Kumar, Pramod; Jodha, Ajay Singh; Misra, Manoj; Khatri, P.K.

    2008-01-01

    In nuclear hardened structures and AFV's, special shielding materials are being used to provide protection from radiations generated in nuclear blast. However, in blast an intense heat pulse is also generated along with radiation. Currently used shield does not take care of this heat pulse. Defence Laboratory, Jodhpur has developed multi transformation phase change materials (MTPCM) based cool panels for passive moderation of temperature in severe desert heat. The MTPCM contains light nuclei of hydrogen, carbon and oxygen, and thus can absorb good amount of neutrons. MTPCM can also absorb intense heat pulse along with heat generated by secondary fires during blast as its latent heat (160-170 J/g) without significant rise in temperature (melting point 36-38 deg. C). Thus MTPCM can provide protection against both radiation as well as heat pulse generated in a nuclear blast along with its designed regular function of passively moderating temperature below 40 deg C during severe desert summer. A study has been undertaken to explore multiple applications of MTPCM panel. Protection factor provided by standard MTPCM panels against neutron and gamma radiations (both initial and fall out) were measured and results compared with PF provided by special lining pad currently being used in AFV's and field structures for nuclear protection. It is observed that MTPCM provides good PF (2.17) against neutron which is better than currently used shield pads (PFP%1.8). Present paper discusses results of this study. (author)

  3. Development of Point Kernel Shielding Analysis Computer Program Implementing Recent Nuclear Data and Graphic User Interfaces

    International Nuclear Information System (INIS)

    Kang, Sang Ho; Lee, Seung Gi; Chung, Chan Young; Lee, Choon Sik; Lee, Jai Ki

    2001-01-01

    In order to comply with revised national regulationson radiological protection and to implement recent nuclear data and dose conversion factors, KOPEC developed a new point kernel gamma and beta ray shielding analysis computer program. This new code, named VisualShield, adopted mass attenuation coefficient and buildup factors from recent ANSI/ANS standards and flux-to-dose conversion factors from the International Commission on Radiological Protection (ICRP) Publication 74 for estimation of effective/equivalent dose recommended in ICRP 60. VisualShield utilizes graphical user interfaces and 3-D visualization of the geometric configuration for preparing input data sets and analyzing results, which leads users to error free processing with visual effects. Code validation and data analysis were performed by comparing the results of various calculations to the data outputs of previous programs such as MCNP 4B, ISOSHLD-II, QAD-CGGP, etc

  4. Non-combustible nuclear radiation shields with high hydrogen content

    International Nuclear Information System (INIS)

    Hall, W.C.; Peterson, J.M.

    1978-01-01

    The invention relates to compositions, methods of production, and uses of non-combustible nuclear radiation shields, with particular emphasis on those containing a high concentration of hydrogen atoms, especially effective for moderating neutron energy by elastic scatter, dispersed as a discontinuous phase in a continuous phase of a fire resistant matrix

  5. Method for limiting movement of a thermal shield for a nuclear reactor, and thermal shield displacement limiter therefor

    International Nuclear Information System (INIS)

    Meuschke, R.E.; Boyd, C.H.

    1989-01-01

    This patent describes a method of limiting the movement of a thermal shield of a nuclear reactor. It comprises: machining at least four (4) pockets in upper portions of a thermal shield circumferentially about a core barrel of a nuclear reactor to receive key-wave inserts; tapping bolt holes in the pockets of the thermal shield to receive bolts; positioning key-wave inserts into the pockets of the thermal shield to be bolted in place with the bolt holes; machining dowel holes at least partially through the positioned key-way inserts and the thermal shield to receive dowel pins; positioning dowel pins in the dowel holes in the key-way insert and thermal shield to tangentially restrain movement of the thermal shield relative to the core barrel; sliding limiter keys into the key-way inserts and bolting the limiter keys to the core barrel to tangentially restrain movement of the thermal shield relative and the core barrel while allowing radial and axial movement of the thermal shield relative to the core barrel; machining dowel holes through the limiter key and at least partially through the core barrel to receive dowel pins; positioning dowel pins in the dowel holes in the limiter key and core barrel to restrain tangential movement of the thermal shield relative to the core barrel of the nuclear reactor

  6. A shielded measurement system for irradiated nuclear fuel measurements

    International Nuclear Information System (INIS)

    Mosby, W.R.; Aumeier, S.E.; Klann, R.T.

    1999-01-01

    The US Department of Energy (DOE) is driving a transition toward dry storage of irradiated nuclear fuel (INF), toward characterization of INF for final disposition, and toward resumption of measurement-based material control and accountability (MC and A) efforts for INF. For these reasons, the ability to efficiently acquire radiological measurements of INF in a dry environment is important. The DOE has recently developed a guidance document proposing MC and A requirements for INF. The intent of this document is to encourage the direct measurement of INF on inventory within DOE. The guidance document reinforces and clarifies existing material safeguards requirements as they pertain to INF. Validation of nuclear material contents of non-self-protecting INF must be accomplished by direct measurement, application of validated burnup codes using qualified initial fissile content, burnup data, and age or by other valid means. The fuel units must remain intact with readable identification numbers. INF may be subject to periodic inventories with visual item accountability checks. Quantitative measurements may provide greater assurance of the integrity of INF inventories at a lower cost and with less personnel exposure than visual item accountability checks. Currently, several different approaches are used to measure the radiological attributes of INF. Although these systems are useful for a wide variety of applications, there is currently no relatively inexpensive measurement system that is readily deployable for INF measurements for materials located in dry storage. The authors present the conceptual design of a shielded measurement system (SMS) that could be used for this purpose. The SMS consists of a shielded enclosure designed to house a collection of measurement systems to allow measurements on spent fuel outside of a hot cell. The phase 1 SMS will contain 3 He detectors and ionization chambers to allow for gross neutron and gamma-ray measurements. The phase 2 SMS

  7. Device for sealing and shielding a nuclear fuel storage tank

    International Nuclear Information System (INIS)

    Masaki, Gengo.

    1975-01-01

    Object: To provide a shield device for opening and closing a great opening in a relay-storage-tank within a hot cell for temporarily storing a nuclear fuel, in which the device is simplified in construction and which can perform the opening and closing operation in simple, positive and quick manner. Structure: A biological shield is positioned upwardly of an opening of a nuclear fuel storage tank to render an actuator inoperative. A sealing plate, which is pivotally supported by a plurality of support rod devices from the biological shield for parallel movement with respect to the biological shield, comes in contact with a resilient seal disposed along the entire peripheral edge of the opening to form an air-tight seal therebetween. In order to release the opening, the actuator is first actuated and the end of the sealing plate is horizontally pressed by a piston rod thereof. Then, the sealing plate is moved along the line depicted by the end of the support rod in the support rod devices and as a consequence, the plate is moved away from the resilient seal in the peripheral edge of the opening. When a driving device is actuated to travel the plate along the aforesaid line while maintaining the condition as described, the biological device moves along the guide. (Kamimura, M.)

  8. Shielding modification and safety review on the nuclear ship 'Mutsu'

    International Nuclear Information System (INIS)

    Osanai, Masao

    1978-01-01

    The Japan Atomic Energy Commission (JAEC) called on the Japan Nuclear Ship Development Agency (JNSDA) for shielding modification and safety review on the nuclear ship ''Mutsu'', and JNSDA has conducted the research and development (R and D) to meet the request of JAEC for the above two items. Concerning the shield modification, the following matters are described: the study on the cause of radiation leakage which was concluded to the fast neutron streaming, the conceptual design for this modification, the mock up experiment for shielding utilizing JRR-4, the basic design following on the conceptual design, including the detailed drawings of the modified construction and the shielding analysis using RADHEAT-V3 code, and the relating experiments such as the heat transfer test of the primary shielding structure and the test of strength in stranding. As for the safety review, the survey of the troubles and the technical problems having been experienced in the light water reactor plants of land use, for example, fuel integrity, stress corrosion cracking and the leakage of steam generator tubes, the revision of the design so as to adapt to current safety standards and regulations, for example, in-service inspection, the setting of additional leak detectors in the primary cooling system, the modification of emergeney filters, etc., and the review of the design and construction corresponding to recent R and D works, such as re-evaluation of the core design, cooling capability of natural circulation, thermal stress analysis of main pipings, and the evaluation of ECCS performance are presented . (Nakai, Y.)

  9. γ-ray shielding behaviors of some nuclear engineering materials

    International Nuclear Information System (INIS)

    Mann, Kulwinder Singh

    2017-01-01

    The essential requirement of a material to be used for engineering purposes at nuclear establishments is its ability to attenuate the most penetrating ionizing radiations, gamma (γ)-rays. Mostly, high-Z materials such as heavy concrete, lead, mercury, and their mixtures or alloys have been used in the construction of nuclear establishments and thus termed as nuclear engineering materials (NEM). The NEM are classified into two categories, namely opaque and transparent, depending on their behavior towards the visible spectrum of EM waves. The majority of NEM are opaque. By contrast, various types of glass, which are transparent to visible light, are necessary at certain places in the nuclear establishments. In the present study, γ-ray shielding behaviors (GSB) of six glass samples (transparent NEM) were evaluated and compared with some opaque NEM in a wide range of energy (15 keV–15 MeV) and optical thickness (OT). The study was performed by computing various γ-ray shielding parameters (GSP) such as the mass attenuation coefficient, equivalent atomic number, and buildup factor. A self-designed and validated computer-program, the buildup factor-tool, was used for various computations. It has been established that some glass samples show good GSB, thus can safely be used in the construction of nuclear establishments in conjunction with the opaque NEM as well

  10. γ-ray shielding behaviors of some nuclear engineering materials

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Kulwinder Singh [Dept. of Physics, D.A.V. College, Punjab (India)

    2017-06-15

    The essential requirement of a material to be used for engineering purposes at nuclear establishments is its ability to attenuate the most penetrating ionizing radiations, gamma (γ)-rays. Mostly, high-Z materials such as heavy concrete, lead, mercury, and their mixtures or alloys have been used in the construction of nuclear establishments and thus termed as nuclear engineering materials (NEM). The NEM are classified into two categories, namely opaque and transparent, depending on their behavior towards the visible spectrum of EM waves. The majority of NEM are opaque. By contrast, various types of glass, which are transparent to visible light, are necessary at certain places in the nuclear establishments. In the present study, γ-ray shielding behaviors (GSB) of six glass samples (transparent NEM) were evaluated and compared with some opaque NEM in a wide range of energy (15 keV–15 MeV) and optical thickness (OT). The study was performed by computing various γ-ray shielding parameters (GSP) such as the mass attenuation coefficient, equivalent atomic number, and buildup factor. A self-designed and validated computer-program, the buildup factor-tool, was used for various computations. It has been established that some glass samples show good GSB, thus can safely be used in the construction of nuclear establishments in conjunction with the opaque NEM as well.

  11. γ-Ray Shielding Behaviors of Some Nuclear Engineering Materials

    Directory of Open Access Journals (Sweden)

    Kulwinder Singh Mann

    2017-06-01

    Full Text Available The essential requirement of a material to be used for engineering purposes at nuclear establishments is its ability to attenuate the most penetrating ionizing radiations, gamma (γ-rays. Mostly, high-Z materials such as heavy concrete, lead, mercury, and their mixtures or alloys have been used in the construction of nuclear establishments and thus termed as nuclear engineering materials (NEM. The NEM are classified into two categories, namely opaque and transparent, depending on their behavior towards the visible spectrum of EM waves. The majority of NEM are opaque. By contrast, various types of glass, which are transparent to visible light, are necessary at certain places in the nuclear establishments. In the present study, γ-ray shielding behaviors (GSB of six glass samples (transparent NEM were evaluated and compared with some opaque NEM in a wide range of energy (15 keV–15 MeV and optical thickness (OT. The study was performed by computing various γ-ray shielding parameters (GSP such as the mass attenuation coefficient, equivalent atomic number, and buildup factor. A self-designed and validated computer-program, the buildup factor-tool, was used for various computations. It has been established that some glass samples show good GSB, thus can safely be used in the construction of nuclear establishments in conjunction with the opaque NEM as well.

  12. A Shifting Shield Provides Protection Against Cosmic Rays

    Science.gov (United States)

    Kohler, Susanna

    2017-12-01

    The Sun plays an important role in protecting us from cosmic rays, energetic particles that pelt us from outside our solar system. But can we predict when and how it will provide the most protection, and use this to minimize the damage to both pilotedand roboticspace missions?The Challenge of Cosmic RaysSpacecraft outside of Earths atmosphere and magnetic field are at risk of damage from cosmic rays. [ESA]Galactic cosmic rays are high-energy, charged particles that originate from astrophysical processes like supernovae or even distant active galactic nuclei outside of our solar system.One reason to care about the cosmic rays arriving near Earth is because these particles can provide a significant challenge for space missions traveling above Earths protective atmosphere and magnetic field. Since impacts from cosmic rays can damage human DNA, this risk poses a major barrier to plans for interplanetary travel by crewed spacecraft. And roboticmissions arent safe either: cosmic rays can flip bits, wreaking havoc on spacecraft electronics as well.The magnetic field carried by the solar wind provides a protective shield, deflecting galactic cosmic rays from our solar system. [Walt Feimer/NASA GSFCs Conceptual Image Lab]Shielded by the SunConveniently, we do have some broader protection against galactic cosmic rays: a built-in shield provided by the Sun. The interplanetary magnetic field, which is embedded in the solar wind, deflects low-energy cosmic rays from us at the outer reaches of our solar system, decreasing the flux of these cosmic rays that reach us at Earth.This shield, however, isnt stationary; instead, it moves and changes as the strength and direction of the solar wind moves and changes. This results in a much lower cosmic-ray flux at Earth when solar activity is high i.e., at the peak of the 11-year solar cycle than when solar activity is low. This visible change in local cosmic-ray flux with solar activity is known as solar modulation of the cosmic ray flux

  13. Validation of nuclear models used in space radiation shielding applications

    International Nuclear Information System (INIS)

    Norman, Ryan B.; Blattnig, Steve R.

    2013-01-01

    A program of verification and validation has been undertaken to assess the applicability of models to space radiation shielding applications and to track progress as these models are developed over time. In this work, simple validation metrics applicable to testing both model accuracy and consistency with experimental data are developed. The developed metrics treat experimental measurement uncertainty as an interval and are therefore applicable to cases in which epistemic uncertainty dominates the experimental data. To demonstrate the applicability of the metrics, nuclear physics models used by NASA for space radiation shielding applications are compared to an experimental database consisting of over 3600 experimental cross sections. A cumulative uncertainty metric is applied to the question of overall model accuracy, while a metric based on the median uncertainty is used to analyze the models from the perspective of model development by examining subsets of the model parameter space.

  14. Nuclear characteristics of epoxy resin as a space environment neutron shielding

    Energy Technology Data Exchange (ETDEWEB)

    Adeli, Ruhollah [Nuclear Science and Technology Research Institute, Yazd (Iran, Islamic Republic of). Central Iran Research Complex; Shirmardi, Seyed Pezhman [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of). Radiation Application Research School; Mazinani, Saideh [Amirkabir Nanotechnology Research Institute, Tehran (Iran, Islamic Republic of); Ahmadi, Seyed Javad [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of). Nuclear Fuel Cycle Research School

    2017-03-15

    In recent years many investigations have been done for choosing applicable light neutron shielding in space environmental applications. In this study, we have considered the neutron radiation-protective characteristics of neat epoxy resin, a thermoplastic polymer material and have compared it with various candidate materials in neutron radiation protection such as Al 6061 alloy and Polyethylene. The aim of this investigation is the effect of type of moderator for fast neutron, notwithstanding neutron absorbers fillers. The nuclear interactions and the effective dose at shields have been studied with the Monte Carlo N-Particle transport code (MCNP), using variance reductions to reduce the relative error. Among the candidates, polymer matrix showed a better performance in attenuating fast neutrons and caused a lower neutron and secondary photon effective dose.

  15. Efficacy of corneal eye shields in protecting patients' eyes from laser irradiation.

    Science.gov (United States)

    Russell, S W; Dinehart, S M; Davis, I; Flock, S T

    1996-07-01

    The continuing development of new types and applications of lasers has appeared to surpass the development of specific eye protection for these lasers. There are a variety of eye shields on the market, but few are specifically designed for laser protection. Our purpose was to test a variety of eye shields by two parameters, light transmission and temperature rise, and to determine from these measurements the most protective shield for patients. We tested four plastic shields, one metal shield, and two sets of tanning goggles for temperature rise and light transmission when irradiated with a beam from a flashlamp-pumped, pulsed-dye laser. The temperature rise at the surface of the shield opposite the laser impacts was no more than 0.2 degree C in any case. White light was transmitted at significant levels through several of the shields, but yellow light transmittance was noted only through the green eye shield. Our measurements indicate that all except the green shield appeared safe from transmission of the 585-nm radiant energy. However, the optimal laser eye shield, in our opinion, would be a composite of several different shields' characteristics.

  16. Studies for calculations of the thicknesses of shielding necessary for implementation of a nuclear medicine service with PET-CT

    International Nuclear Information System (INIS)

    Nascimento, Erika M.; Lopes Filho, Ferdinand J.; Souza, Milena Thays B. de; Aragao Filho, Geraldo L.

    2013-01-01

    The thickness of shielding for controlled and surrounding areas must be considered in terms of the PET-CT equipment installation. However, for a project to install a PET-CT requires the participation of technologists, engineers and architects so that together we can meet the requirements of radiological protection at low cost, enabling its installation and maintenance in nuclear medical centers and hospitals. The objective of this paper is to describe the calculations needed to shield a nuclear medicine center that will install a PET-CT equipment and describe how the participation of other professionals can contribute to a lower cost

  17. Shield nuclear design for the 5-kWe TE system

    International Nuclear Information System (INIS)

    Keshishian, V.

    1972-01-01

    The nuclear analysis of the 5-kW(e) reactor shield is presented. Calculation methods and optimization techniques used are presented. Borated stainless steel was selected for the gamma ray shield with tungsten alloy as an alternate. The total shield weight was calculated to be 355 lb. (U.S.)

  18. Self Shielding in Nuclear Fissile Assay Using LSDS

    International Nuclear Information System (INIS)

    Lee, Yong Deok; Park, Chang Je; Park, Geun Il; Song, Kee Chan

    2012-01-01

    The new technology for isotopic fissile material contents assay is under development at KAERI using lead slowing down spectrometer(LSDS). LSDS is very sensitive to distinguish fission signals from each fissile isotope in spent and recycled fuel. The accumulation of spent fuel is current big issue. The amount of spent fuels will reach the maximum storage capacity of the pools soon. Therefore, an interim storage must be searched and it should be optimized in design by applying accurate fissile content. When the storage has taken effect, all the nuclear materials must be also specified and verified for safety, economics and management. Generally, the spent fuel from PWR has unburned ∼1 % U235, produced ∼0.5 % plutonium from decay chain, ∼3 % fission products, ∼ 0.1 % minor actinides (MA) and uranium remainder. About 1.5 % fissile materials still exist in the spent fuel. Therefore, for reutilization of fissile materials in spent fuel at SFR, resource material is produced through pyro process. Fissile material contents in resource material must be analyzed before fabricating SFR fuel for reactor safety and economics. In assay of fissile content of spent fuel and recycled fuel, intense radiation background gives limitation on the direct analysis of fissile materials. However, LSDS is not influenced by such a radiation background in fissile assay. Based on the decided geometry setup, self shielding parameter was calculated at the fuel assay zone by introducing spent fuel or pyro produced nuclear material. When nuclear material is inserted into the assay area, the spent fuel assembly or pyro recycled fuel material perturbs the spatial distribution of the slowing down neutrons in lead and the prompt fast fission neutrons produced by fissile materials are also perturbed. The self shielding factor is interpreted as that how much of absorption is created inside the fuel area when it is in the lead. Self shielding effect provides a non-linear property in the isotopic

  19. Use of multiple radiographic techniques for nuclear shielding development

    Energy Technology Data Exchange (ETDEWEB)

    Day, S., E-mail: dayse@mcmaster.ca [McMaster Univ., McMaster Nuclear Reactor, Hamilton, Ontario (Canada)

    2016-01-15

    The McMaster Nuclear Reactor (MNR) is a medium-sized research reactor located on the campus of McMaster University in Hamilton, Ontario. The largest nuclear reactor on a Canadian university campus, MNR is an open-pool, light water research reactor, Equipped with both in-core and ex-core irradiation facilities, MNR serves research, education, and industrial needs while producing radioisotopes for medical applications. Presently the University is preparing for the installation of a positron beam line facility at one of the MNR beam ports. One of five such facilities worldwide, the McMaster Intense Positron Beam Facility (MIPBF) will provide orders of magnitude more positrons than a standard bench-top arrangement, making possible experiments not previously feasible. Funded by the Canadian Foundation for Innovation and the Ontario Research Foundation, the MIPBF project is a collaborative effort between positron groups at McMaster, Western, and York universities and researchers and staff at MNR, The project has involved design and fabrication of both the positron production and transport system and custom biological shielding. The MIPBF shielding fabrication is scheduled to be complete by fall 2015 followed shortly by installation and commissioning testing at MNR. Positron beam availability is planned for later in 2016. Applications include defect characterization and surface analysis of advanced engineering materials and fundamental science experiments on antimatter properties, The MIPBF will be the latest addition to the extensive array of materials-related facilities at McMaster University. (author)

  20. Use of multiple radiographic techniques for nuclear shielding development

    International Nuclear Information System (INIS)

    Day, S.

    2016-01-01

    The McMaster Nuclear Reactor (MNR) is a medium-sized research reactor located on the campus of McMaster University in Hamilton, Ontario. The largest nuclear reactor on a Canadian university campus, MNR is an open-pool, light water research reactor, Equipped with both in-core and ex-core irradiation facilities, MNR serves research, education, and industrial needs while producing radioisotopes for medical applications. Presently the University is preparing for the installation of a positron beam line facility at one of the MNR beam ports. One of five such facilities worldwide, the McMaster Intense Positron Beam Facility (MIPBF) will provide orders of magnitude more positrons than a standard bench-top arrangement, making possible experiments not previously feasible. Funded by the Canadian Foundation for Innovation and the Ontario Research Foundation, the MIPBF project is a collaborative effort between positron groups at McMaster, Western, and York universities and researchers and staff at MNR, The project has involved design and fabrication of both the positron production and transport system and custom biological shielding. The MIPBF shielding fabrication is scheduled to be complete by fall 2015 followed shortly by installation and commissioning testing at MNR. Positron beam availability is planned for later in 2016. Applications include defect characterization and surface analysis of advanced engineering materials and fundamental science experiments on antimatter properties, The MIPBF will be the latest addition to the extensive array of materials-related facilities at McMaster University. (author)

  1. Specialty glass development for radiation shielding windows and nuclear waste immobilization

    International Nuclear Information System (INIS)

    Mandal, S.; Ghorui, S.; Roy Chowdhury, A.; Sen, R.; Chakraborty, A.K.; Sen, S.; Maiti, H.S.

    2015-01-01

    The technology of two important varieties of specialty glasses, namely high density Radiation Shielding Window (RSW) glass and specialty glass beads of borosilicate composition have been successfully developed in CGCRI with an aim to meet the countries requirement. Radiation Shielding Windows used in nuclear installations, are viewing devices, which allow direct viewing into radioactive areas while still providing adequate protection to the operating personnel. The glass blocks are stabilized against damage from radiation by introducing cerium in definite proportions. Considering the essentially of developing an indigenous technology to make the country self-sufficient for this critical item, CGCRI has taken up a major programme to develop high lead containing glasses required for RSWs under a MoD with BARC. On the other hand, the specialty glass bead of specific composition and properties is a critical material required for management of radioactive waste in a closed nuclear fuel cycle that is followed by India. During reprocessing of the spent nuclear fuel, high level radio-active liquid waste (HLW) is produced containing unwanted radio isotopes some of which remain radioactive for thousands of years. The need is to immobilize them within a molecular structure so that they will not come out and be released to the ambience and thereby needs to be resolved if nuclear power is to make a significant contribution to the country's power requirement. Borosilicate glass has emerged as the material of choice for immobilization due to its unique random network structure

  2. Shielding considerations for advanced space nuclear reactor systems

    International Nuclear Information System (INIS)

    Angelo, J.P. Jr.; Buden, D.

    1982-01-01

    To meet the anticipated future space power needs, the Los Alamos National Laboratory is developing components for a compact, 100 kW/sub e/-class heat pipe nuclear reactor. The reactor uses uranium dioxide (UO 2 ) as its fuel, and is designed to operate around 1500 k. Heat pipes are used to remove thermal energy from the core without the use of pumps or compressors. The reactor heat pipes transfer mal energy to thermoelectric conversion elements that are advanced versions of the converters used on the enormously successful Voyager missions to the outer planets. Advanced versions of this heat pipe reactor could also be used to provide megawatt-level power plants. The paper reviews the status of this advanced heat pipe reactor and explores the radiation environments and shielding requirements for representative manned and unmanned applications

  3. Carbon-13 isotope effects on 199Hg nuclear shielding

    International Nuclear Information System (INIS)

    Sebald, Angelika; Wrackmeyer, Bernd

    1985-01-01

    Secondary 13 C/ 12 C isotope effects on 199 Hg nuclear shielding (Δdeltasup(i)( 199 Hg)) are of interest because of the unusual shift to high frequency which has been observed for a few alkyl mercury compounds. Continuing interest in the NMR parameters of mercury compounds prompted a search for the values Δdeltasup(i)( 199 Hg) in a greater variety of organomercurials. This should help to find out about the range of Δdeltasup(i)( 199 Hg) and to obtain a firmer basis for the discussion of the high-frequency shifts. The data and experimental conditions are given for chemical shifts delta 199 Hg, coupling constants sup(n)J( 199 Hg 13 C) and 13 C/ 12 C isotope shifts Δdeltasup(i)( 199 Hg) of fourteen 199 Hg organomercury compounds. The results are discussed. (author)

  4. Nuclear magnetic shielding tensors of 207Pb2+ in Pb(NO3)2

    International Nuclear Information System (INIS)

    Lutz, O.; Nolle, A.

    1980-01-01

    The NMR signals of 207 Pb were observed in a single crystal of Pb(NO 3 ) 2 and could be assigned to the four different Pb 2+ sites by the dependence of the linewidths on the orientation. Four different nuclear magnetic shielding tensors with equal principal values but with different characteristic vectors could be determined. The symmetry of the shielding tensors is in agreement with the symmetry at the Pb 2+ sites. It is shown, that intermolecular contributions can not account for the anisotropy of the nuclear magnetic shielding, which is 3 0 / 00 of the isotropic absolute magnetic shielding. (orig.)

  5. Radiation protection in nuclear medicine

    International Nuclear Information System (INIS)

    Corstens, F.

    1989-01-01

    Aspects of radiation protection in nuclear medicine and the role of the Dutch Society for Nuclear Medicine in these are discussed. With an effective dose-equivalence of averaged 3 mSv per year per nuclear medical examination and about 200.000 examinations per year in the Netherlands, nuclear medicine contributes only to a small degree to the total averaged radiation dose by medical treating. Nevertheless from the beginning, besides to protection of environment and personnel, much attention has been spent by nuclear physicians to dose reduction with patients. Replacing of relatively long living radionuclides like 131 I by short living radionuclides like 99m Tc is an example. In her education and acknowledgement policy the Dutch Society for Nuclear Medicine spends much attention to aspects of radiation reduction. (author). 3 tabs

  6. Physical protection of nuclear material

    International Nuclear Information System (INIS)

    1975-01-01

    Full text: An Advisory Group met to consider the up-dating and extension of the Recommendations for the Physical Protection of Nuclear Material, produced in 1972. Twenty-seven experts from 11 countries and EURATOM were present. Growing concern has been expressed in many countries that nuclear material may one day be used for acts of sabotage or terrorism. Serious attention is therefore being given to the need for States to develop national systems for the physical protection of nuclear materials during use, storage and transport throughout the nuclear fuel cycle which should minimize risks of sabotage or theft. The revised Recommendations formulated by the Advisory Group include new definitions of the objectives of national systems of physical protection and proposals for minimizing possibilities of unauthorized removal and sabotage to nuclear facilities. The Recommendations also describe administrative or organizational steps to be taken for this purpose and the essential technical requirements of physical protection for various types and locations of nuclear material, e.g., the setting up of protected areas, the use of physical barriers and alarms, the need for security survey, and the need of advance arrangements between the States concerned in case of international transportation, among others. (author)

  7. The distribution property of shielding materials used in radiological protection

    International Nuclear Information System (INIS)

    Costa, Paulo R.

    1996-01-01

    A parametric model for the distribution of the radiation scattered by shielding materials is proposed. The advantages regarding to chemical composition or to linear attenuation coefficient of the media as a function of energy are presented. Comparative results between the model and experimental data are reported

  8. Improved Nuclear Reactor and Shield Mass Model for Space Applications

    Science.gov (United States)

    Robb, Kevin

    2004-01-01

    New technologies are being developed to explore the distant reaches of the solar system. Beyond Mars, solar energy is inadequate to power advanced scientific instruments. One technology that can meet the energy requirements is the space nuclear reactor. The nuclear reactor is used as a heat source for which a heat-to-electricity conversion system is needed. Examples of such conversion systems are the Brayton, Rankine, and Stirling cycles. Since launch cost is proportional to the amount of mass to lift, mass is always a concern in designing spacecraft. Estimations of system masses are an important part in determining the feasibility of a design. I worked under Michael Barrett in the Thermal Energy Conversion Branch of the Power & Electric Propulsion Division. An in-house Closed Cycle Engine Program (CCEP) is used for the design and performance analysis of closed-Brayton-cycle energy conversion systems for space applications. This program also calculates the system mass including the heat source. CCEP uses the subroutine RSMASS, which has been updated to RSMASS-D, to estimate the mass of the reactor. RSMASS was developed in 1986 at Sandia National Laboratories to quickly estimate the mass of multi-megawatt nuclear reactors for space applications. In response to an emphasis for lower power reactors, RSMASS-D was developed in 1997 and is based off of the SP-100 liquid metal cooled reactor. The subroutine calculates the mass of reactor components such as the safety systems, instrumentation and control, radiation shield, structure, reflector, and core. The major improvements in RSMASS-D are that it uses higher fidelity calculations, is easier to use, and automatically optimizes the systems mass. RSMASS-D is accurate within 15% of actual data while RSMASS is only accurate within 50%. My goal this summer was to learn FORTRAN 77 programming language and update the CCEP program with the RSMASS-D model.

  9. Multiconfigurational self-consistent field calculations of nuclear shieldings using London atomic orbitals

    DEFF Research Database (Denmark)

    Ruud, Kenneth; Helgaker, Trygve; Kobayashi, Rika

    1994-01-01

    to corresponding individual gauges for localized orbitals (IGLO) results. The London results show better basis set convergence than IGLO, especially for heavier atoms. It is shown that the choice of active space is crucial for determination of accurate nuclear shielding constants.......Nuclear shielding calculations are presented for multiconfigurational self-consistent field wave functions using London atomic orbitals (gauge invariant atomic orbitals). Calculations of nuclear shieldings for eight molecules (H2O, H2S, CH4, N2, CO, HF, F2, and SO2) are presented and compared...

  10. Radiation protection in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Volodin, V; Hanson, G P

    1993-12-31

    The goal of this Chapter is to give a general outline of the essential principles and procedures for radiation protection in a nuclear medicine department where radionuclides are used for diagnosis and therapy. More detailed recommendations regarding radiation protection in nuclear medicine are given in the publications of the International Commission on Radiation Protection (ICRP, publications 25, 57, 60) and in ILO/IAEA/WHO Manual on Radiation Protection in Hospitals and General Practice (Volume 2: Unsealed Sources, WHO, Geneva, 1975), on which this Chapter is based. This chapter is not intended to replace the above-mentioned international recommendations on radiation protection, as well as existing national regulations on this subject, but intended only to provide guidance for implementing these recommendations in clinical practice

  11. Radiation protection in nuclear medicine

    International Nuclear Information System (INIS)

    Volodin, V.; Hanson, G.P.

    1992-01-01

    The goal of this Chapter is to give a general outline of the essential principles and procedures for radiation protection in a nuclear medicine department where radionuclides are used for diagnosis and therapy. More detailed recommendations regarding radiation protection in nuclear medicine are given in the publications of the International Commission on Radiation Protection (ICRP, publications 25, 57, 60) and in ILO/IAEA/WHO Manual on Radiation Protection in Hospitals and General Practice (Volume 2: Unsealed Sources, WHO, Geneva, 1975), on which this Chapter is based. This chapter is not intended to replace the above-mentioned international recommendations on radiation protection, as well as existing national regulations on this subject, but intended only to provide guidance for implementing these recommendations in clinical practice

  12. Shielding tests for a new ship for the transport of spent nuclear fuels

    International Nuclear Information System (INIS)

    Ito, D.; Kitano, T.; Akiyama, H.; Ueki, K.; Sanui, T.

    1998-01-01

    a new ship for the transport of spent nuclear fuels which uses serpentine concrete as its major shielding material has been constructed. The shielding calculations are based on DOT3.5 code (CCC-276) and the DLC23). Experiments with Cf-252 and Co-60 sources were carried out to confirm the validity of this method of calculating the shielding effectiveness of serpentine concrete. In these experiments, neutron and gamma-ray dose equivalent rates were measured in various arrangements to simulate the shielding structures of the ship, the calculations for each arrangement were performed by this shielding calculation method. For both neutron and gamma-rays, the calculation results agreed with the experiments very well, confirming that this calculation method used in the ship's shielding design is valid. Two kinds of on-board gamma-ray shielding tests were performed to confirm the ship's actual shielding effectiveness. In one kind of test, gamma-ray dose equivalent rates were measured for each shielding wall using Co-60 sources. In the other kind of test, gamma-ray dose equivalent rates in the ship's accommodation area were measured when a strong Co-60 source was placed in a loaded shipping cask's position. In both gamma-ray shielding tests all measured dose equivalent rates were less than the calculated values, confirming that the ship's actual shielding is sufficient to meet safety requirements. (authors)

  13. Evaluation of additional lead shielding in protecting the physician from radiation during cardiac interventional procedures

    International Nuclear Information System (INIS)

    Chida, Koichi; Zuguchi, Masayuki; Morishima, Yoshiaki; Katahira, Yoshiaki; Chiba, Hiroo

    2005-01-01

    Since cardiac interventional procedures deliver high doses of radiation to the physician, radiation protection for the physician in cardiac catheterization laboratories is very important. One of the most important means of protecting the physician from scatter radiation is to use additional lead shielding devices, such as tableside lead drapes and ceiling-mounted lead acrylic protection. During cardiac interventional procedures (cardiac IVR), however, it is not clear how much lead shielding reduces the physician dose. This study compared the physician dose [effective dose equivalent (EDE) and dose equivalent (DE)] with and without additional shielding during cardiac IVR. Fluoroscopy scatter radiation was measured using a human phantom, with an ionization chamber survey meter, with and without additional shielding. With the additional shielding, fluoroscopy scatter radiation measured with the human phantom was reduced by up to 98%, as compared with that without. The mean EDE (whole body, mean±SD) dose to the operator, determined using a Luxel badge, was 2.55±1.65 and 4.65±1.21 mSv/year with and without the additional shielding, respectively (p=0.086). Similarly, the mean DE (lens of the eye) to the operator was 15.0±9.3 and 25.73±5.28 mSv/year, respectively (p=0.092). In conclusion, although tableside drapes and lead acrylic shields suspended from the ceiling provided extra protection to the physician during cardiac IVR, the reduction in the estimated physician dose (EDE and DE) during cardiac catheterization with additional shielding was lower than we expected. Therefore, there is a need to develop more ergonomically useful protection devices for cardiac IVR. (author)

  14. Characterization of serpentine. A potential nuclear shielding material

    International Nuclear Information System (INIS)

    Sengupta, A.; Rajeswari, B.; Kadam, R.M.; Kshirsagar, R.J.

    2012-01-01

    The use of serpentine as a potential nuclear shielding material necessitates a chemical quality control of the samples before its use in reactors. With this in view, characterization of these mineral samples was carried out using inductively coupled plasma atomic emission spectrometry (ICP-AES) and Instrumental neutron activation analysis (INAA) methods. The analytical results obtained by both ICP-AES and NAA techniques were found to be comparable. Na, Cr, Co, Zn, and Cu were found to be present in all samples of Indian origin while Ga, Ag, Ni, and Cd were found to below the limits of detection. A comparison on the detection limits of elements of interest was also carried out by both the analytical techniques and found to be in good agreement. An infrared spectroscopic investigation was also carried out on all the mineral samples. Bands at 3,689 and 3,648 cm -1 were attributed to inner and outer hydroxyl stretching of Mg-OH, respectively. The weak and broad band centered around 3,416 cm -1 was assigned due to the stretching vibrations of the adsorbed water molecules while three bands at 1076, 1022 and 968 cm -1 were prescribed to the vibrations of the SiO 4 tetrahedra. (author)

  15. Numerical simulation of a reinforced concrete shield around a nuclear reactor

    International Nuclear Information System (INIS)

    Mahama, Mumuni Salifu

    1996-02-01

    Ghana currently operates a Research Reactor and other nuclear facilities including a Gamma Irradiation Facility, a Radiographic Non-Destructive Testing laboratory and would be operating in the nearest future a Radiotherapy Centre. Each of these has a concrete radiation shield as a major safety device. In carrying out its functions, a concrete radiation shield may be subjected to thermal and mechanical stresses. A facility for analysing these stresses is desirable. Two computer codes have been developed under this programme for radiation shielding computation and stress analysis of cylindrical reactor shields. (au)

  16. Apparatus for sealing a rotatable shield plug in a liquid metal nuclear reactor

    International Nuclear Information System (INIS)

    Winkleblack, R.K.

    1980-01-01

    An apparatus for sealing a rotatable shield plug in a nuclear reactor having liquid metal coolant is described. The apparatus includes a dip -ring seal adapted to provide a fluid barrier between the liquid metal and the atmosphere and to permit rotation of the shield plug. The apparatus also includes a static seal for the rotatable shield plug located between the dip-ring seal and the liquid metal. The static seal isolates the dip-ring seal from the liquid metal vapor during operation at power and can be disengaged for rotation of the shield plug

  17. Radiation protection in nuclear facilities

    International Nuclear Information System (INIS)

    Piechowski, J.; Lochard, J.; Lefaure, Ch.; Schieber, C.; Schneider, Th; Lecomte, J.F.; Delmont, D.; Boitel, S.; Le Fauconnier, J.P.; Sugier, A; Zerbib, J.C.; Barbey, P.

    1998-01-01

    Close ties exist between nuclear safety and radiation protection. Nuclear safety is made up of all the arrangements taken to prevent accidents occurring in nuclear facilities, these accidents would certainly involved a radiological aspect. Radiation protection is made up of all the arrangements taken to evaluate and reduce the impact of radiation on workers or population in normal situations or in case of accident. In the fifties the management of radiological hazards was based on the quest for minimal or even zero risk. This formulation could lead to call some activities in question whereas the benefits for the whole society were evident. Now a new attitude more aware of the real risks and of no wasting resources prevails. This attitude is based on the ALARA principle whose purpose is to maintain the exposure to radiation as low as reasonably achievable taking into account social and economic concerns. This document regroups articles illustrating different aspects of the radiation protection in nuclear facilities such as a research center, a waste vitrification workshop and a nuclear power plant. The surveillance of radiological impacts of nuclear sites on environment is examined, a point is made about the pending epidemiologic studies concerning La Hague complex. (A.C.)

  18. Radiation shielding

    International Nuclear Information System (INIS)

    Yue, D.D.

    1979-01-01

    Details are given of a cylindrical electric penetration assembly for carrying instrumentation leads, used in monitoring the performance of a nuclear reactor, through the containment wall of the reactor. Effective yet economical shielding protection against both fast neutron and high-energy gamma radiation is provided. Adequate spacing within the assembly allows excessive heat to be efficiently dissipated and means of monitoring all potential radiation and gas leakage paths are provided. (UK)

  19. Shielding device for control rod in nuclear reactor

    International Nuclear Information System (INIS)

    Sakamaki, Kazuo; Tomatsu, Tsutomu.

    1995-01-01

    The device of the present invention shields radiation emitted from control rods to greatly reduce an operator's radiation exposure even if reactor water level is lowered and the upper portion of the control rod is exposed upon inspection of a BWR type reactor. Namely, a shield assembly has a structure comprising a set of four columnar shields in a two-row and two-column arrangement, which can be inserted into a control rod guide tube. Upon conducting inspection, the control rod is lowered into the control rod guide tube, and in this state, the columnar shields of the shield assembly are inserted to the control rod in the control rod guide tube. With such procedures, the upper portion of the control rod protruded from the control rod guide tube is covered with the shield assembly. As a result, radiation leaked from the control rod is shielded. Accordingly, irradiation in the reactor due to leaked radiation can be prevented thereby enabling to reduce an operator's radiation exposure. (I.S.)

  20. Physics contributions to radiation protection in nuclear power plants

    International Nuclear Information System (INIS)

    Krueger, F.W.

    1980-01-01

    Physical research and physical methods can essentially contribute to radiation protection in nuclear power plants. With their aid, properties of radiation sources can be determined, and calculations of radiation shields can be performed. In the present paper, such tasks are analyzed, the state of the art of their solution is evaluated, and trends of further work are shown. Focal points of the present study are the calculation of properties of radiation sources outside the reactor (fission products, activated corrosion products, decontamination facilities for contaminated media), exact and engineering methods for calculating radiation fields also in inhomogeneous shields, and classification of concretes for gamma-ray shielding. Objectives, possibilities, and problems of standardization of such activities are discussed. (author)

  1. Radiation shielding properties of a novel cement–basalt mixture for nuclear energy applications

    Energy Technology Data Exchange (ETDEWEB)

    Ipbüker, Cagatay; Nulk, Helena; Gulik, Volodymyr [University of Tartu, Institute of Physics (Estonia); Biland, Alex [HHK Technologies, Houston (United States); Tkaczyk, Alan Henry, E-mail: alan@ut.ee [University of Tartu, Institute of Physics (Estonia)

    2015-04-01

    Highlights: • Basalt fiber is a relatively cheap material that can be used as reinforcement. • Gamma-ray attenuation remains relatively stable with addition of basalt fiber. • Neutron attenuation remains relatively stable with addition of basalt fiber. • Cement–basalt mixture has a good potential for use in nuclear energy applications. - Abstract: The radiation shielding properties of a new proposed building material, a novel cement–basalt fiber mixture (CBM), are investigated. The authors analyze the possibility of this material to be a viable substitute to outgoing materials in nuclear energy applications, which will lead to a further sustained development of nuclear energy in the future. This computational study involves four types of concrete with various amounts of basalt fiber in them. The gamma-ray shielding characteristics of proposed CBM material are investigated with the help of WinXCom program, whereas the neutron shielding characteristics are computed by the Serpent code. For gamma-ray shielding, we find that the attenuation coefficients of concretes with basalt fibers are not notably influenced by the addition of fibers. For neutron shielding, additional basalt fiber in mixture presents negligible effect on neutron radiation shielding. With respect to radiation shielding, it can be concluded that basalt fibers have good potential as an addition to heavyweight concrete for nuclear energy applications.

  2. Radiation shielding properties of a novel cement–basalt mixture for nuclear energy applications

    International Nuclear Information System (INIS)

    Ipbüker, Cagatay; Nulk, Helena; Gulik, Volodymyr; Biland, Alex; Tkaczyk, Alan Henry

    2015-01-01

    Highlights: • Basalt fiber is a relatively cheap material that can be used as reinforcement. • Gamma-ray attenuation remains relatively stable with addition of basalt fiber. • Neutron attenuation remains relatively stable with addition of basalt fiber. • Cement–basalt mixture has a good potential for use in nuclear energy applications. - Abstract: The radiation shielding properties of a new proposed building material, a novel cement–basalt fiber mixture (CBM), are investigated. The authors analyze the possibility of this material to be a viable substitute to outgoing materials in nuclear energy applications, which will lead to a further sustained development of nuclear energy in the future. This computational study involves four types of concrete with various amounts of basalt fiber in them. The gamma-ray shielding characteristics of proposed CBM material are investigated with the help of WinXCom program, whereas the neutron shielding characteristics are computed by the Serpent code. For gamma-ray shielding, we find that the attenuation coefficients of concretes with basalt fibers are not notably influenced by the addition of fibers. For neutron shielding, additional basalt fiber in mixture presents negligible effect on neutron radiation shielding. With respect to radiation shielding, it can be concluded that basalt fibers have good potential as an addition to heavyweight concrete for nuclear energy applications

  3. 76 FR 63942 - Notice of Issuance of Final Determination Concerning a Surgical Mask With a Protective Eye Shield

    Science.gov (United States)

    2011-10-14

    ... Determination Concerning a Surgical Mask With a Protective Eye Shield AGENCY: U.S. Customs and Border Protection... country of origin of a Surgical Mask with a Protective Eye Shield. Based upon the facts presented, CBP has concluded in the final determination that Turkey is the country of origin of the Surgical Mask with a...

  4. Nuclear low and environmental protection

    International Nuclear Information System (INIS)

    Vencato, A.C.B.

    1982-01-01

    The imperceptible character of nuclear radiation on the human senses and their harmful effects on living beings and the environment is emphasised. This is based on a review of published works about the concepts of energy and ecology. The potential hazards of a possible nuclear accident and the damage it would cause to a community as well as the problem of radioactive waste disposal are raised. The conclusions and recommendations of the Brazilian Physics Society's Report on Nuclear Pollution are endorsed. The general guidelines of Brazilian Legislation are presented. The legal aspects of nuclear reactor licensing in West Germany, the United Kingdom, France and Brazil are shown from the point of view of the applicable legal system, the licensing bodies, the general frame and scope, public participation, technical safety bodies, as well as the inspection procedures. The concepts of absolute and objective civil responsibility for nuclear damage are reviewed. The judicial principle of equity is considered in view of the exceptional character of the nuclear risk. The main aspects of the international Conventions of Paris, Brussels and Viena on civil ability of nuclear damage are presented. Some philosphical and judicial questions are discussed emphasising the instrumentality of the law control and effective protection. The final suggestion is the exchange of ideas with a view to obtain the maximum safety in the operation of nuclear installations. (author) [pt

  5. Analysis and Testing of a Composite Fuselage Shield for Open Rotor Engine Blade-Out Protection

    Science.gov (United States)

    Pereira, J. Michael; Emmerling, William; Seng, Silvia; Frankenberger, Charles; Ruggeri, Charles R.; Revilock, Duane M.; Carney, Kelly S.

    2016-01-01

    The Federal Aviation Administration is working with the European Aviation Safety Agency to determine the certification base for proposed new engines that would not have a containment structure on large commercial aircraft. Equivalent safety to the current fleet is desired by the regulators, which means that loss of a single fan blade will not cause hazard to the Aircraft. The NASA Glenn Research Center and The Naval Air Warfare Center (NAWC), China Lake, collaborated with the FAA Aircraft Catastrophic Failure Prevention Program to design and test lightweight composite shields for protection of the aircraft passengers and critical systems from a released blade that could impact the fuselage. LS-DYNA® was used to predict the thickness of the composite shield required to prevent blade penetration. In the test, two composite blades were pyrotechnically released from a running engine, each impacting a composite shield with a different thickness. The thinner shield was penetrated by the blade and the thicker shield prevented penetration. This was consistent with pre-test LS-DYNA predictions. This paper documents the analysis conducted to predict the required thickness of a composite shield, the live fire test from the full scale rig at NAWC China Lake and describes the damage to the shields as well as instrumentation results.

  6. Basic nuclear data and reactor shielding design formulaire PROPANE Do

    International Nuclear Information System (INIS)

    Estiot, J.C.; Salvatores, M.; Trapp, J.P.

    1979-01-01

    This paper presents a calculational scheme - formulaire PROPANE - to calculate the deep neutron penetration in the fast reactor shield. The emphasis is put on the multigroup data and method approximations. The performances of this formulaire are presented

  7. Uranium-lead shielding for nuclear material transportation systems

    International Nuclear Information System (INIS)

    Lusk, E.C.; Miller, N.E.; Basham, S.J. Jr.

    1978-01-01

    The basis for the selection of shielding materials for spent fuel shipping containers is described with comments concerning the favorable and unfavorable aspects of steel, lead, and depleted uranium. A concept for a new type of material made of depleted uranium and lead is described which capitalizes on the best cask shielding characteristics of both materials. This cask shielding is made by filling the shielding cavity with pieces of depleted uranium and then backfilling the interstitial voids with lead. The lead would be bonded to the uranium and also to the cask shells if desired. Shielding density approaching 80 percent of that of solid uranium could be achieved, while a density of 65 percent is readily obtainable. This material should overcome the problems of the effect of lead melting in the fire accident, high thermal gradients at uranium-stainless steel interfaces and at a major reduction in cost over that of a solid uranium shielded cask. A development program is described to obtain information on the properties of the composite material to aid in design analysis and licensing and to define the fabrication techniques

  8. Prevalence of Protective Shielding Utilization for Radiation Dose Reduction in Adult Patients Undergoing Body Scanning Using Computed Tomography.

    Science.gov (United States)

    Safiullah, Shoaib; Patel, Roshan; Uribe, Brittany; Spradling, Kyle; Lall, Chandana; Zhang, Lishi; Okhunov, Zhamshid; Clayman, Ralph V; Landman, Jaime

    2017-10-01

    Ionizing radiation is implicated in nearly 2% of malignancies in the United States; radiation shields prevent unnecessary radiation exposure during medical imaging. Contemporary radiation shield utilization for adult patients in the United States is poorly defined. Therefore, we evaluated the prevalence of protective shielding utilization in adult patients undergoing CT scans in United States' hospitals. An online survey was sent to established radiology departments randomly selected from the 2015 American Hospital Association Guide. Radiology departments conducting adult CT imaging were eligible; among 370 eligible departments, 215 departments accepted the study participation request. Questions focused on shielding practices during CT imaging of the eyes, thyroid, breasts, and gonads. Prevalence data were stratified per hospital location, size, and type. Main outcomes included overall protective shielding utilization, respondents' belief and knowledge regarding radiation safety, and organ-specific shielding prevalence. Sixty-seven of 215 (31%) hospitals completed the survey; 66 (99%) reported familiarity with the ALARA (as low as reasonably achievable) principle and 56 (84%) affirmed their belief that shielding is beneficial. Only 60% of hospitals employed shielding during CT imaging; among these institutions, shielding varied based on CT study: abdominopelvic CT (13, 33%), head CT (33, 83%), or chest CT (30, 75%). Among surveyed hospitals, 40% do not utilize CT shielding despite the majority acknowledging the ALARA principle and agreeing that shielding is a beneficial practice. Failure to address the low prevalence of protective shielding may lead to poor community health due to increased risk of radiation-related cancers.

  9. Nuclear reactions and self-shielding effects of gamma-ray database for nuclear materials

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Mitsutane; Noda, Tetsuji [National Research Institute for Metals, Tsukuba, Ibaraki (Japan)

    2001-03-01

    A database for transmutation and radioactivity of nuclear materials is required for selection and design of materials used in various nuclear reactors. The database based on the FENDL/A-2.0 on the Internet and the additional data collected from several references has been developed in NRIM site of 'Data-Free-Way' on the Internet. Recently, the function predicted self-shielding effect of materials for {gamma}-ray was added to this database. The user interface for this database has been constructed for retrieval of necessary data and for graphical presentation of the relation between the energy spectrum of neutron and neutron capture cross section. It is demonstrated that the possibility of chemical compositional change and radioactivity in a material caused by nuclear reactions can be easily retrieved using a browser such as Netscape or Explorer. (author)

  10. Nuclear reactions and self-shielding effects of gamma-ray database for nuclear materials

    International Nuclear Information System (INIS)

    Fujita, Mitsutane; Noda, Tetsuji

    2001-01-01

    A database for transmutation and radioactivity of nuclear materials is required for selection and design of materials used in various nuclear reactors. The database based on the FENDL/A-2.0 on the Internet and the additional data collected from several references has been developed in NRIM site of 'Data-Free-Way' on the Internet. Recently, the function predicted self-shielding effect of materials for γ-ray was added to this database. The user interface for this database has been constructed for retrieval of necessary data and for graphical presentation of the relation between the energy spectrum of neutron and neutron capture cross section. It is demonstrated that the possibility of chemical compositional change and radioactivity in a material caused by nuclear reactions can be easily retrieved using a browser such as Netscape or Explorer. (author)

  11. Physical Protection of Nuclear Safeguards Technology

    International Nuclear Information System (INIS)

    Hoskins, Richard

    2004-01-01

    IAEA's Nuclear Security Plan is established to assist Member States in implementing effective measures against nuclear terrorism. Four potential threats were identified: theft of nuclear weapon, nuclear explosive device, radiological dispersal device and an attack on radiation facility. In order to achieve effective protection of nuclear materials and facilities, the IAEA sponsored the Convention of the Physical Protection of Nuclear Materials which focuses on the protection of nuclear materials 'in international transport. The IAEA also promoted INFCIRC/255 entitled the Physical Protection of Nuclear Materials and Nuclear Facilities and published TECDOC/967 for the protection of nuclear materials and facilities against theft and sabotage and during transport. Assistance is available for the Member States through the International Physical Protection Advisory Service (IPPAS) and the International Nuclear Security Advisory Service (INSServ). (author)

  12. Study on the use of gonadal protection shields during paediatric pelvic X-rays.

    Science.gov (United States)

    Sikand, Manoj; Stinchcombe, S; Livesley, P J

    2003-11-01

    There are national guidelines issued by all hospital radiology departments concerning the use of gonadal protection shields for taking X-rays of the pelvis. It is important to follow these guidelines especially when paediatric X-rays are taken. Gonads are very susceptible to radiation as they fall directly in the line of radiation exposure when pelvic X-rays are taken. To examine whether these guidelines were being followed. This audit considered 355 radiographs taken in a 6-month period on 149 patients, under the age of 16 years, attending the orthopaedic department at King's Mill Hospital. In only 23% of the cases studied, the correct use of gonad protection shields had been performed. In 67% of the unprotected patients, the shields were not used at all. In the remainder, the shield was incorrectly applied. Out of all the patients, 45% had more than one X-ray thus exposing the gonads to unnecessary radiation. In addition, 8% of patients had a CT scan, 6% had fluoroscopy and 42% had radiographs of other regions of the body. Guidelines should be adhered to as far as possible and efforts always be made to decrease radiation exposure. Application of the current guidelines excludes the first X-ray exposure of the female pelvis and of the pelvis of trauma patients from the use of shields, thus adding to the number of the X-rays done without protection.

  13. Shielding designs and tests of a new exclusive ship for transporting spent nuclear fuels

    International Nuclear Information System (INIS)

    Ono, M.; Ito, D.; Kitano, T.; Ueki, K.; Akiyama, H.; Obara, I.; Sanui, T.

    2000-01-01

    The Rokuei-Maru, a ship built specially for the transport of spent nuclear fuels in casks, was launched April in 1996. She is the first ship to comply with special Japanese regulations, KAISA 520, based on the INF code. DOT3.5 and MCNP-4A were used for the evaluation of dose equivalent rates of her shielding structures. On-board gamma-ray shielding tests were executed to confirm the effectiveness of the ship's shielding performance. The tests confirmed that effective shielding has been achieved and the dose equivalent rate in the accommodation and other inhabited spaces is sufficiently lower than the regulated limitations. This was achieved by employing the appropriate calculation methods and shielding materials. (author)

  14. Lead thickness in shielding in the protection of radiodiagnostic staff

    International Nuclear Information System (INIS)

    Russell, J.G.B.; Hufton, A.P.

    1988-01-01

    The authors indicate the principles which can be used to apply cost-benefit analysis to radiation protection of staff in an X-ray department. The cost of saving radiation exposure to staff by varying the lead equivalence of lead gowns and lead protective screens is calculated. The cost is compared with the financial values of the detriment as assessed by the National Radiological Protection Board. The expenditure required to avoid a man-Sv for staff protection in diagnostic departments is suggested. In the examples taken it is found that the larger staff dose reductions, and often the cheaper reductions, can be obtained by reducing the radiation dose to the patient. There are, of course, major additional advantages to the patient in reducing this dose. (author)

  15. Shield materials recommended for space power nuclear reactors

    Science.gov (United States)

    Kaszubinski, L. J.

    1973-01-01

    Lithium hydride is recommended for neutron attenuation and depleted uranium is recommended for gamma ray attenuation. For minimum shield weights these materials must be arranged in alternate layers to attenuate the secondary gamma rays efficiently. In the regions of the shield near the reactor, where excessive fissioning occurs in the uranium, a tungsten alloy is used instead. Alloys of uranium such as either the U-0.5Ti or U-8Mo are available to accommodate structural requirements. The zone-cooled casting process is recommended for lithium hydride fabrication. Internal honeycomb reinforcement to control cracks in the lithium hydride is recommended.

  16. The computer code system for reactor radiation shielding in design of nuclear power plant

    International Nuclear Information System (INIS)

    Li Chunhuai; Fu Shouxin; Liu Guilian

    1995-01-01

    The computer code system used in reactor radiation shielding design of nuclear power plant includes the source term codes, discrete ordinate transport codes, Monte Carlo and Albedo Monte Carlo codes, kernel integration codes, optimization code, temperature field code, skyshine code, coupling calculation codes and some processing codes for data libraries. This computer code system has more satisfactory variety of codes and complete sets of data library. It is widely used in reactor radiation shielding design and safety analysis of nuclear power plant and other nuclear facilities

  17. Shielding analysis method applied to nuclear ship 'MUTSU' and its evaluation based on experimental analyses

    International Nuclear Information System (INIS)

    Yamaji, Akio; Miyakoshi, Jun-ichi; Iwao, Yoshiaki; Tsubosaka, Akira; Saito, Tetsuo; Fujii, Takayoshi; Okumura, Yoshihiro; Suzuoki, Zenro; Kawakita, Takashi.

    1984-01-01

    Procedures of shielding analysis are described which were used for the shielding modification design of the Nuclear Ship ''MUTSU''. The calculations of the radiation distribution on board were made using Sn codes ANISN and TWOTRAN, a point kernel code QAD and a Monte Carlo code MORSE. The accuracies of these calculations were investigated through the analysis of various shielding experiments: the shield tank experiment of the Nuclear Ship ''Otto Hahn'', the shielding mock-up experiment for ''MUTSU'' performed in JRR-4, the shielding benchmark experiment using the 16 N radiation facility of AERE Harwell and the shielding effect experiment of the ship structure performed in the training ship ''Shintoku-Maru''. The values calculated by the ANISN agree with the data measured at ''Otto Hahn'' within a factor of 2 for fast neutrons and within a factor of 3 for epithermal and thermal neutrons. The γ-ray dose rates calculated by the QAD agree with the measured values within 30% for the analysis of the experiment in JRR-4. The design values for ''MUTSU'' were determined in consequence of these experimental analyses. (author)

  18. Investigation of Radiation Protection Methodologies for Radiation Therapy Shielding Using Monte Carlo Simulation and Measurement

    Science.gov (United States)

    Tanny, Sean

    The advent of high-energy linear accelerators for dedicated medical use in the 1950's by Henry Kaplan and the Stanford University physics department began a revolution in radiation oncology. Today, linear accelerators are the standard of care for modern radiation therapy and can generate high-energy beams that can produce tens of Gy per minute at isocenter. This creates a need for a large amount of shielding material to properly protect members of the public and hospital staff. Standardized vault designs and guidance on shielding properties of various materials are provided by the National Council on Radiation Protection (NCRP) Report 151. However, physicists are seeking ways to minimize the footprint and volume of shielding material needed which leads to the use of non-standard vault configurations and less-studied materials, such as high-density concrete. The University of Toledo Dana Cancer Center has utilized both of these methods to minimize the cost and spatial footprint of the requisite radiation shielding. To ensure a safe work environment, computer simulations were performed to verify the attenuation properties and shielding workloads produced by a variety of situations where standard recommendations and guidance documents were insufficient. This project studies two areas of concern that are not addressed by NCRP 151, the radiation shielding workload for the vault door with a non-standard design, and the attenuation properties of high-density concrete for both photon and neutron radiation. Simulations have been performed using a Monte-Carlo code produced by the Los Alamos National Lab (LANL), Monte Carlo Neutrons, Photons 5 (MCNP5). Measurements have been performed using a shielding test port designed into the maze of the Varian Edge treatment vault.

  19. FCXSEC: multigroup cross-section libraries for nuclear fuel cycle shielding calculations

    International Nuclear Information System (INIS)

    Ford, W.E. III; Webster, C.C.; Diggs, B.R.; Pevey, R.E.; Croff, A.G.

    1980-05-01

    Starting with the pseudo-composition-independent VITAMIN-C cross-sectin library, composition-dependent fine-(171n-36γ) and broad-group (22n-21γ) self-shielded AMPX master, broad-group microscopic ANISN-formatted, and broad-group macroscopic ANISN-formatted cross-section libraries were generated to be used for nuclear fuel cycle shielding calculations. The specifications for the data and the procedure used to prepare the libraries are described

  20. Minimizing exposure in nuclear medicine through optimum use of shielding devices

    International Nuclear Information System (INIS)

    Rutherford, B.L.; King, S.H.; Erdman, M.C.; Miller, K.L.

    1991-01-01

    Exposure to radiation from nuclear medicine nuclides can be minimized through the use of various shielding devices. This paper reviews the dose reductions achieved through use of various syringe shields, lead aprons, leaded gloves, and several types of eyeglass lenses for 67 Ga, 99m Tc, 131 I and 201 Tl. The authors have found that combination of devices can best provide for minimizing doses

  1. Principles of protection against nuclear smuggling

    International Nuclear Information System (INIS)

    Erickson, S.A.; Martin, D.D.

    2001-01-01

    Full text: The smuggling of nuclear materials is a matter of grave consequence, and if allowed to occur in sufficient amount, could lead to nuclear terrorism or nuclear proliferation. This paper describes a framework created for the Department of Energy's contribution to national and international efforts to prevent and detect nuclear smuggling. With such a framework, opportunities for rapid gains in smuggling prevention can be found as well as funding gaps. It is useful first to define the threat, which is then used to drive specifications and planning for technology and tactics. The exact numbers involved in the threat are not important here. It is enough to understand that the goal is to prevent the smuggling of sufficient quantities of weapon-usable material from a protected site to anywhere where it could be used for proliferation or terrorism. However, this should not be interpreted as a definition of some minimum amount of nuclear material that would be useful to detect and interdict. The useful amount can be smuggled in two, three or many individual smuggling trips, and so the quantity searched for may be considerably less. Next, a range of possible actions can be listed. One category involves promoting deterrence of nuclear smuggling by portraying the likely consequences of nuclear smuggling as mostly negative for smugglers. Another category involves detecting nuclear materials, by anyone at anytime. Increasing the probability of detection is not the same thing as enhancing deterrence. What deters is perception. If the perception that nuclear smuggling is unlikely to succeed is spread to potential smugglers, deterrence will be achieved. The cost of such a campaign is likely less than actually enhancing the probability of detection. There are major pitfalls in such a campaign, however. These include the release of information that might enhance the capability of smugglers and the chance that the campaign will be unconvincing. Another mode of deterrence

  2. Anticorrosional protection in nuclear power station objects

    International Nuclear Information System (INIS)

    Czarnocki, A.; Kwiatkowski, A.

    1976-01-01

    The distribution and qualities of chemical protection and demands concerning preparation of the bottom for protecting coats in nuclear power station objects are discussed. The solutions of protections applied abroad and in the objects of ''MARIA'' reactor are presented. (author)

  3. Advanced methodologies of evaluating the radiation sources and ionising radiation shieldings for reducing the irradiation in nuclear field personnel

    International Nuclear Information System (INIS)

    Pantazi, D.; Mateescu, S.; Stanciu, M.

    2003-01-01

    One of the technical measures of protection against ionizing radiations is the radiation shielding. The process of implementing modern and efficient methods of evaluating the radiation shielding implies advanced calculation methods. That means using from simpler 1-D or 2-D computing codes such as MicroShield or QAD up to systems of codes such as SCALE (containing several independent modules) or the Monte Carlo multipurpose and many particles, MCNP, transport code. The main objective of this work is to present the Monte Carlo based evaluation of the dose rates from the CANDU type spent fuel all along the path of its handling up to intermediate storage. These values will be then compared with the values obtained from calculations with different computing programs. To obtain this objective two problems were approached: - establishing geometrical models according to the definition used by MCNP code so that the characteristics of CANDU type nuclear fuel are taking into account; - checking the validity of the proposed models by comparing the MCNP results with those obtained with other computing codes specific for shielding evaluation and radiation dose calculation

  4. Shielding calculations for ships carrying irradiated nuclear fuel

    International Nuclear Information System (INIS)

    Dean, M.H.

    1985-01-01

    A number of ships have been constructed to carry irradiated fuel from Japan to the U.K. and France, for reprocessing. About 20 transport flasks may be carried on each voyage. Permanent shielding must be provided on the ships to ensure that no member of the crew receives an annual dose greater than a specified limit. As the fuel is of varying type and radiation history, and as flasks of differing designs are used, many shielding calculations are needed. There are a number of difficulties in making shielding calculations for the ships. The geometry is complex, dimensions are large and considerable air spaces are involved. The paper considers possible methods of calculation. The line-of-sight method is chosen for most of the calculations, for both γ-radiation and neutrons. The basic data which is used in the calculations is described. As the methods of calculation are somewhat approximate, it is necessary to provide confirmation that they are sufficiently accurate. Validation has been provided in two ways. First, measurements have been made on board one of the ships, Pacific Crane, and these have been checked against calculation. Second, a simplified model of the flasks and ship has been set up, and calculations checked against more sophisticated methods. Results of the validation checks are presented, and it is shown that adequate accuracy is achieved. (author)

  5. Strengthening the composite protective shield of light-weight ship against ballistic impacts: analytical and experimental

    Directory of Open Access Journals (Sweden)

    I. Jalili

    Full Text Available Light and medium protection for small naval vessels guarantees their high performance and safety during the guard duties. In this study, a protective shield fabricated from Dyneema HB25 fibers has been utilized as an add-on layer on the coast guard boat hull. Finite element analyses have been conducted using Chocron's model. Two standards of gun-fire were employed and various thicknesses of the composite layers were examined by ballistic impacts. Afterward, numerical simulations results compared with experiments and revealed a good consistency. Finally, some graphs have been presented to help designers for choosing more convenient shield based on protection and weight characteristics after judgment of vessel requirements.

  6. Shielding and filtering techniques to protect sensitive instrumentation from electromagnetic interference caused by arc welding

    International Nuclear Information System (INIS)

    Kalechstein, W.

    1997-01-01

    Electromagnetic interference (EMI) caused by arc welding is a concern for sensitive CANDU instrumentation and control equipment, especially start-up instrumentation (SUI) and ion chamber instruments used to measure neutron flux at low power. Measurements of the effectiveness of simple shielding and filtering techniques that may be applied to limit arc welding electromagnetic emissions below the interference threshold are described. Shielding configurations investigated include an arrangement in which the welding power supply, torch (electrode holder), interconnecting cables and welder operator were housed in a single enclosure and a more practical configuration of separate shields for the power supply, cables and operator with torch. The two configuration were found to provide 30 dB and 26 dB attenuation, respectively, for arc welder electric-field emissions and were successful in preventing EMI in SUI set up just outside the shielding enclosures. Practical improvements that may be incorporated in the shielding arrangement to facilitate quick setup in the field in a variety of application environments, while maintaining adequate EMI protection, are discussed. (author)

  7. Nuclear emergencies and protective actions

    International Nuclear Information System (INIS)

    Sjoeblom, Klaus

    1995-01-01

    Although technical improvements have increased the safety of new and old nuclear power plants, many simultaneous component failures and/or human errors are improbable but possible. Both the plant (on-site) and the nearby area (off-site) have emergency plans. Rescue service authorities are responsible of the off-site. The main protective actions are sheltering, evacuation and iodine ingestion. The Loviisa off-site emergency plan assumes that a major part of this population takes care of their own protective actions; Rescue service authorities can then concentrate on the coordination activities and to those people who need help. To be able to carry out the protective actions timely and effectively the people should have information on radiation risk and emergency planning. In case of a potential accident the local population should follow the rescue service information and know how to shelter and how to evacuate themselves. Though there are many stockpiles of iodine pellets in the area the rescue service authorities recommend that each household should purchase iodine pellets for their own need. The utility and the rescue service authorities have distributed information brochures to all homes within 30 km from Loviisa NPP since 1990. This brochure gives information on radiation and protective actions in case of an accident. Because the brochures might not stay available and so also the local telephone book contains this information

  8. Protection and control of nuclear materials

    International Nuclear Information System (INIS)

    Jalouneix, J.; Winter, D.

    2007-01-01

    In the framework of the French regulation on nuclear materials possession, the first liability is the one of operators who have to know at any time the quantity, quality and localization of any nuclear material in their possession. This requires an organization of the follow up and of the inventory of these materials together with an efficient protection against theft or sabotage. The French organization foresees a control of the implementation of this regulation at nuclear facilities and during the transport of nuclear materials by the minister of industry with the sustain of the institute of radiation protection and nuclear safety (IRSN). This article presents this organization: 1 - protection against malevolence; 2 - national protection and control of nuclear materials: goals, administrative organization, legal and regulatory content (authorization, control, sanctions), nuclear materials protection inside facilities (physical protection, follow up and inventory, security studies), protection of nuclear material transports (physical protection, follow up), control of nuclear materials (inspection at facilities, control of nuclear material measurements, inspection of nuclear materials during transport); 3 - international commitments of France: non-proliferation treaty, EURATOM regulation, international convention on the physical protection of nuclear materials, enforcement in France. (J.S.)

  9. Shielding repair and comprehensive safety inspection of the nuclear-powered ship Mutsu

    International Nuclear Information System (INIS)

    Takada, Etsuo

    1982-01-01

    Eight years after the radiation leakage accident, the nuclear-powered ship Mutsu returned again to its home port Ominato. During the period, for four years, the n.s. Mutsu was subjected to shielding repair and comprehensive inspection at Sasebo port. In the future, the ship will start on experimental navigation after its functional and power-up tests. The works of shielding repair and the comprehensive inspection with subsequent repair are described in technical aspects. The basic policy of the repair was two points, i.e. the usage of shielding materials excellent in shielding capacity, less in radioactivation and enduring operating temperature, and structural strength resisting ship-hull acceleration, shock and vibration, enabling easy maintenance and inspection. Comprehensive inspection was made on not only machinery integrity but also the design itself. (Mori, K.)

  10. Protective shielding parameters of diagnostic x-ray rooms in some hospitals in Benue State

    International Nuclear Information System (INIS)

    Agba, E.H.; Gemanam, S.; Sombo, T.

    2011-01-01

    Protective shielding parameters of diagnostic x-ray units at Federal Medical Centre, Makurdi, Baki Hospital, Gboko and Mkar Christian Hospital, Gboko have been determined using a radiation meter, (Inspector, Exp.S.E). The parameters determined include: Operating potential, Workload and Use factors of each diagnostic x-ray room. These parameters were used to estimate the primary and secondary protective barriers for the hospitals. The primary and secondary protective barrier values at Mkar Christian Hospital, Baki Hospital, Gboko and Federal Medical Centre, Makurdi are found to be: 11.0±0.11 x10 -1 mm and 9.0±9x10 -2 mm; 6.0±6.0x10 -1 mm and 6.0±6.0x10 -2 mm; and 7.0±7.0x10 -1 mm and 6.0±6.0x10 -2 mm respectively. The wall thicknesses around the x-ray rooms of the respective hospitals are 300±3.0x1 0 -1 mm for Mkar Christian Hospital and Federal Medical Centre, Makurdi, while that of Baki Hospital, Gboko is 270±2.7x10 -1 mm. The measured wall thicknesses are seen to be adequate protective structural shields on the basis of International NCRP Standards on Structural Shielding.

  11. Personal radiation protection in nuclear industry

    International Nuclear Information System (INIS)

    Gol'dshtejn, D.S.; Koshcheev, V.S.

    1983-01-01

    Specific peculiarities of organization of personal radiation protection at various nuclear industry enterprises when dealing with radioactive and other toxic substances are illuminated. Effect of heatin.g and cooling microclimate is discussed. Medical and technical requirements for personal protection means and tasks of personal protection in the field of nuclear industry are considered in short along with some peculiarities of application of different kinds of personal protection means and psychological aspects of personnel protection

  12. Shielding calculations for ships carrying irradiated nuclear fuel

    International Nuclear Information System (INIS)

    Burstall, R.F.; Dean, M.H.

    1983-01-01

    A number of ships have been constructed to carry irradiated fuel from Japan to the UK and France, for reprocessing. About twenty transport flasks may be carried on each voyage. Permanent shielding must be provided on the ships to ensure that no member of the crew receives an annual dose rate greater than a specified limit. As the fuel is of varying type and radiation history, and as flasks of differing designs are used, many calculations are needed. There are a number of difficulties in making shielding calculations for the ships. The geometry is complex, dimensions are large, and considerable air spaces are involved. The paper considers possible methods of calculation. The line-of-sight method is chosen for most of the calculations, for both gamma radiation and neutrons. The basic data which is used in the calculations is described. As the methods of calculation are somewhat approximate, it is necessary to provide confirmation that they are sufficiently accurate. Validation has been provided in two ways. First, measurements have been made on board the ships, and these have been checked against calculation. Second, a simplified model of the flasks and ship has been set up, and calculations checked against more sophisticated methods. Results of the validation checks are presented, and it is shown that adequate accuracy is achieved. (author)

  13. The use and relevance of gonad protection shields in children during hips radiography

    OpenAIRE

    Silva, C. A.; Silva, P. N.; Ventura, Sandra Rua

    2010-01-01

    Considering that ionizing radiation effects are cumulative and the gonads are particularly sensitive to these effects, and also the clinical importance of pelvic radiographs in children, the excess of radiation exposure to the gonads must be avoided. The purpose of this study is to demonstrate the relevance of the correct use of gonad protection shields and to evaluate their use on the hip radiographs performed in a reference clinical institution, through the retrospective analysis of p...

  14. Analytical model for relativistic corrections to the nuclear magnetic shielding constant in atoms

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Rodolfo H. [Facultad de Ciencias Exactas, Universidad Nacional del Nordeste, Avenida Libertad 5500 (3400), Corrientes (Argentina)]. E-mail: rhromero@exa.unne.edu.ar; Gomez, Sergio S. [Facultad de Ciencias Exactas, Universidad Nacional del Nordeste, Avenida Libertad 5500 (3400), Corrientes (Argentina)

    2006-04-24

    We present a simple analytical model for calculating and rationalizing the main relativistic corrections to the nuclear magnetic shielding constant in atoms. It provides good estimates for those corrections and their trends, in reasonable agreement with accurate four-component calculations and perturbation methods. The origin of the effects in deep core atomic orbitals is manifestly shown.

  15. Analytical model for relativistic corrections to the nuclear magnetic shielding constant in atoms

    International Nuclear Information System (INIS)

    Romero, Rodolfo H.; Gomez, Sergio S.

    2006-01-01

    We present a simple analytical model for calculating and rationalizing the main relativistic corrections to the nuclear magnetic shielding constant in atoms. It provides good estimates for those corrections and their trends, in reasonable agreement with accurate four-component calculations and perturbation methods. The origin of the effects in deep core atomic orbitals is manifestly shown

  16. Fire protection at nuclear power plants

    International Nuclear Information System (INIS)

    1999-11-01

    The guide presents specific requirements for the design and implementation of fire protection arrangements at nuclear power plants and for the documents relating to the fire protection that are to be submitted to STUK (Finnish Radiation and Nuclear Safety Authority). Inspections of the fire protection arrangements to be conducted by STUK during the construction and operation of the power plants are also described in this guide. The guide can also be followed at other nuclear facilities

  17. Nuclear data needs for fast breeder reactor shielding

    International Nuclear Information System (INIS)

    Oblow, E.M.; Perey, F.G.

    1978-11-01

    A review of neutron and gamma-ray cross section data needs for fast reactor shielding is presented in light of the recent advances made in assessing these needs through sensitivity studies. Total and partial cross sections and energy and angular distribution data for neutrons are surveyed as well as gamma-ray production cross sections. The strengths and deficiencies of currently available benchmark-quality integral experiments are also discussed with respect to their use in creating adjusted cross section libraries for design work. The availability of first round covariance data in ENDF/B-IV and plans for ENDF/B-V are also reviewed. This latter information makes it possible to quantitatively assess the quality of current cross section data libraries and also puts adjustment and data assessment procedures on a firmer basis

  18. Nuclear energy, environmental protection and international conflicts

    International Nuclear Information System (INIS)

    Menke-Glueckert, P.

    1975-01-01

    Some general and some critical remarks on: nuclear energy as an image for politics; nuclear energy as a model for research planning; nuclear controversy; the principle of precaution in nuclear and radiation protection law; reactor safety on probation; advantages and economy of nuclear energy; communication difficulties; the special role of nuclear energy; the need for European site planning; supervision of fissionable materials; the world's energy household in danger; global structure politics and nuclear energy; nuclear energy with a capacity for social innovations. (HP/LN) [de

  19. A New Microwave Shield Preparation for Super High Frequency Range: Occupational Approach to Radiation Protection.

    Science.gov (United States)

    Zaroushani, Vida; Khavanin, Ali; Jonidi Jafari, Ahmad; Mortazavi, Seyed Bagher

    2016-01-01

    Widespread use of X-band frequency (a part of the super high frequency microwave) in the various workplaces would contribute to occupational exposure with potential of adverse health effects.  According to limited study on microwave shielding for the workplace, this study tried to prepare a new microwave shielding for this purpose. We used EI-403 epoxy thermosetting resin as a matrix and nickel oxide nanoparticle with the diameter of 15-35 nm as filler. The Epoxy/ Nickel oxide composites with 5, 7, 9 and 11 wt% were made in three different thicknesses (2, 4 and 6 mm). According to transmission / reflection method, shielding effectiveness (SE) in the X-band frequency range (8-12.5 GHz) was measured by scattering parameters directly given by the 2-port Vector Network Analyzer. The fabricated composites characterized by X-ray Diffraction and Field Emission Scanning Electron Microscope. The best average of shielding effectiveness in each thickness of fabricated composites obtained by 11%-2 mm, 7%-4 mm and 7%-6 mm composites with SE values of 46.80%, 66.72% and 64.52%, respectively. In addition, the 11%-6 mm, 5%-6 mm and 11%-4 mm-fabricated composites were able to attenuate extremely the incident microwave energy at 8.01, 8.51 and 8.53 GHz by SE of 84.14%, 83.57 and 81.30%, respectively. The 7%-4mm composite could be introduced as a suitable alternative microwave shield in radiation protection topics in order to its proper SE and other preferable properties such as low cost and weight, resistance to corrosion etc. It is necessary to develop and investigate the efficacy of the fabricated composites in the fields by future studies.

  20. Study and installation of concrete shielding in the civil engineering of nuclear construction (1960)

    International Nuclear Information System (INIS)

    Dubois, F.

    1960-01-01

    The object of this report is to give technical information about high density concretes which have become very important for radiation biological shielding. The most generally used heavy aggregates (barytes, ilmenite, ferrophosphorus, limonite, magnetite and iron punching) to make these concretes are investigated from the point of view prospecting and physical and chemical characteristics. At first, a general survey of shielding concretes is made involving the study of components, mixing and placing methods, then, a detailed investigation of some high density concretes: barytes concrete, with incorporation of iron punching or iron shot, ferrophosphorus concrete, ilmenite concrete and magnetite concrete, more particularly with regard to grading and mix proportions and testing process. To put this survey in concrete form, two practical designs are described such as they have been carried out at the Saclay Nuclear Station. Specifications are given for diverse concretes and for making the proton-synchrotron 'Saturne' shielding blocks. (author) [fr

  1. Determination of boron in Jabroc wood used as a shielding material in nuclear reactors

    International Nuclear Information System (INIS)

    Kamble, Granthali S.; Manisha, V.; Venkatesh, K.

    2015-01-01

    Jabroc are non-impregnated, densified wood laminates developed commercially for a wide range of industrial applications. Jabroc can be used with other neutron shielding materials such as Lead to form complex shielding structures. Its relative light weight and cleanliness in handling are additional features that make it a suitable candidate for the standard design of neutron shielding equipment. Jabroc can also be impregnated with Boron up to a maximum of 4% to be used in areas where Gamma radiation produced on Neutron capture reaches unacceptable dose rates. Boron impregnated Jabroc wood finds application in TAPS 3 and 4 as a shielding material for the Ion Chambers and the Horizontal Flux Units (HFU). The shielding property of this material is optimized by incorporating requisite amount of boron in wood. Boron content in this material has to be determined accurately prior to its use in the nuclear reactors. In this work a method was standardized to determine boron in Jabroc wood samples to check for conformance to specifications. The wood sample flakes were wetted with saturated barium hydroxide solution and dries under IR. The sample was ashed in a muffle furnace at 600℃ for 2 h

  2. The physical protection of nuclear material

    International Nuclear Information System (INIS)

    1989-12-01

    A Technical Committee on Physical Protection of Nuclear Material met in April-May 1989 to advise on the need to update the recommendations contained in document INFCIRC/225/Rev.1 and on any changes considered to be necessary. The Technical Committee indicated a number of such changes, reflecting mainly: the international consensus established in respect of the Convention on the Physical Protection of Nuclear Material; the experience gained since 1977; and a wish to give equal treatment to protection against the theft of nuclear material and protection against the sabotage of nuclear facilities. The recommendations presented in this IAEA document reflect a broad consensus among Member States on the requirements which should be met by systems for the physical protection of nuclear materials and facilities. 1 tab

  3. The new Brazilian legislation on nuclear protection

    International Nuclear Information System (INIS)

    Fischer, Denise

    1981-10-01

    This paper considers the new system on nuclear protection in Brazil which was established to integrate all government agencies and private bodies involved in nuclear activities. The role of each organisation is analysed in relation to the Brazilian political and administrative structure, in particular that of the Nuclear Energy Commission. (NEA) [fr

  4. Design of an integral missile shield in integrated head assembly for pressurized water reactor at commercial nuclear plants

    International Nuclear Information System (INIS)

    Baliga, Ravi; Watts, Tom Neal; Kamath, Harish

    2015-01-01

    In ICONE22, the authors presented the Integrated Head Assembly (IHA) design concept implemented at Callaway Nuclear Power Plant in Missouri, USA. The IHA concept is implemented to reduce the outage duration and the associated radiation exposure to the workers by reducing critical path time during Plant Refueling Outage. One of the head area components in the IHA is a steel missile shield designed to protect the Control Rod Drive Mechanism (CRDM) assembly from damaging other safety-related components in the vicinity in the Containment. Per Federally implemented General Design Criteria for commercial nuclear plants in the USA, the design of Nuclear Steam Supply System (NSSS) must provide protection from the damages caused by a postulated event of CRDM housing units and their associated parts disengaging from the reactor vessel assembly. This event is considered as a Loss of Coolant Accident (LOCA) and assumes that once the CRDM housing unit and their associated parts disengage from the reactor vessel internals assembly, they travel upward by the water jet with the following sequence of events: Per Reference 1, the drive shaft and control rod cluster are forced out of the reactor core by the differential pressure across the drive shaft with the assumption that the drive shaft and control rod cluster, latched together, are fully inserted when the accident occurs. After the travel, the rod cluster control spider will impact the lower side of the upper support plate inside the reactor vessel fracturing the flexure arms in the joint freeing the drive shaft from the control rod cluster. The control rod cluster is stopped by the upper support plate and will remain below the upper support plate during this accident. However, the drive shaft will continue to accelerate in the upward direction until it is stopped by a safety feature in the IHA. The integral missile shield as a safety feature in the IHA is designed to stop the CRDM drive shaft from moving further up in the

  5. Calculation of shielding and radiation doses for PET/CT nuclear medicine facility

    International Nuclear Information System (INIS)

    Mollah, A.S.; Muraduzzaman, S.M.

    2011-01-01

    Positron emission tomography (PET) is a new modality that is gaining use in nuclear medicine. The use of PET and computed tomography (CT) has grown dramatically. Because of the high energy of the annihilation radiation (511 keV), shielding requirements are an important consideration in the design of a PET or PET/CT imaging facility. The goal of nuclear medicine and PET facility shielding design is to keep doses to workers and the public as low as reasonably achievable (ALARA). Design involves: 1. Calculation of doses to occupants of the facility and adjacent regions based on projected layouts, protocols and workflows, and 2. Reduction of doses to ALARA through adjustment of the aforementioned parameters. The radiological evaluation of a PET/CT facility consists of the assessment of the annual effective dose both to workers occupationally exposed, and to members of the public. This assessment takes into account the radionuclides involved, the facility features, the working procedures, the expected number of patients per year, and so on. The objective of the study was to evaluate shielding requirements for a PET/CT to be installed in the department of nuclear medicine of Bangladesh Atomic Energy Commission (BAEC). Minimizing shielding would result in a possible reduction of structural as well as financial burden. Formulas and attenuation coefficients following the basic AAPM guidelines were used to calculate un-attenuated radiation through shielding materials. Doses to all points on the floor plan are calculated based primarily on the AAPM guidelines and include consideration of broad beam attenuation and radionuclide energy and decay. The analysis presented is useful for both, facility designers and regulators. (author)

  6. Nuclear design of the blanket/shield system for a Tokamak Experimental Power Reactor

    International Nuclear Information System (INIS)

    Abdou, M.A.

    1976-01-01

    The various options and trade-offs in the nuclear design of the blanket/shield for a Tokamak Experimental Power Reactor (TEPR) are investigated. The TEPR size and cost are particularly sensitive to the blanket/shield thickness, Δ/sub BS/, on the inner side of the torus. Radition damage to the components of the superconducting magnet and refrigeration power requirements set lower limits on Δ/sub BS/. These limits are developed in terms of TEPR design parameters such as the wall loading, duty cycle, and frequency of magnet anneals. The study of the nuclear performance of various material compositions shows that mixtures of tungsten, or tantalum, or stainless-steel alloys and boron carbide require the smallest Δ/sub BS/ for a given attenuation. This Δ/sub BS/ has to be doubled if the low induced activation materials graphite and aluminum are used. The space problems are greatly eased in the Argonne National Laboratory ANL-TEPR reference design by using two separate segments of the blanket/shield. The inner segment occupies the region of the high magnetic field, uses very efficient attenuators (tungsten- or tantalum- or stainless-steel-boron carbide mixtures), and is only 1 m thick. The outer blanket/shield is 131 cm and consists of an optimized composition of stainless steel and boron carbide. For the design parameters of 0.2 MW/m 2 neutron wall loading and 50 percent duty cycle, the reactor components can operate satisfactorily up to (a) 10 yr for the stainless-steel first wall, (b) 10 yr for the superconductor composite after which magnet warmup becomes necessary, and (c) 30 yr for the Mylar insulation. Nuclear heat generation rates in the blanket/shield and magnet are well within the practical limits for heat removal

  7. Nuclear analysis and shielding optimisation in support of the ITER In-Vessel Viewing System design

    International Nuclear Information System (INIS)

    Turner, Andrew; Pampin, Raul; Loughlin, M.J.; Ghani, Zamir; Hurst, Gemma; Lo Bue, Alessandro; Mangham, Samuel; Puiu, Adrian; Zheng, Shanliang

    2014-01-01

    The In-Vessel Viewing System (IVVS) units proposed for ITER are deployed to perform in-vessel examination. During plasma operations, the IVVS is located beyond the vacuum vessel, with shielding blocks envisaged to protect components from neutron damage and reduce shutdown dose rate (SDR) levels. Analyses were conducted to determine the effectiveness of several shielding configurations. The neutron response of the system was assessed using global variance reduction techniques and a surface source, and shutdown dose rate calculations were undertaken using MCR2S. Unshielded, the absorbed dose to piezoelectric motors (PZT) was found to be below stable limits, however activation of the primary closure plate (PCP) was prohibitively high. A scenario with shielding blocks at probe level showed significantly reduced PCP contact dose rate, however still marginally exceeded port cell requirements. The addition of shielding blocks at the bioshield plug demonstrated PCP contact dose rates below project requirements. SDR levels in contact with the isolated IVVS cartridge were found to marginally exceed the hands-on maintenance limit. For engineering feasibility, shielding blocks at bioshield level are to be avoided, however the port cell SDR field requires further consideration. In addition, alternative low-activation steels are being considered for the IVVS cartridge

  8. Nuclear analysis and shielding optimisation in support of the ITER In-Vessel Viewing System design

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Andrew, E-mail: andrew.turner@ccfe.ac.uk [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Pampin, Raul [F4E Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain); Loughlin, M.J. [ITER Organisation, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Ghani, Zamir; Hurst, Gemma [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Lo Bue, Alessandro [F4E Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain); Mangham, Samuel [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Puiu, Adrian [F4E Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain); Zheng, Shanliang [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

    2014-10-15

    The In-Vessel Viewing System (IVVS) units proposed for ITER are deployed to perform in-vessel examination. During plasma operations, the IVVS is located beyond the vacuum vessel, with shielding blocks envisaged to protect components from neutron damage and reduce shutdown dose rate (SDR) levels. Analyses were conducted to determine the effectiveness of several shielding configurations. The neutron response of the system was assessed using global variance reduction techniques and a surface source, and shutdown dose rate calculations were undertaken using MCR2S. Unshielded, the absorbed dose to piezoelectric motors (PZT) was found to be below stable limits, however activation of the primary closure plate (PCP) was prohibitively high. A scenario with shielding blocks at probe level showed significantly reduced PCP contact dose rate, however still marginally exceeded port cell requirements. The addition of shielding blocks at the bioshield plug demonstrated PCP contact dose rates below project requirements. SDR levels in contact with the isolated IVVS cartridge were found to marginally exceed the hands-on maintenance limit. For engineering feasibility, shielding blocks at bioshield level are to be avoided, however the port cell SDR field requires further consideration. In addition, alternative low-activation steels are being considered for the IVVS cartridge.

  9. Nuclear analysis methods. Rudiments of radiation protection

    International Nuclear Information System (INIS)

    Roth, E.

    1998-01-01

    The nuclear analysis methods are generally used to analyse radioactive elements but they can be used also for chemical analysis, with fields such analysis and characterization of traces. The principles of radiation protection are explained (ALARA), the biological effects of ionizing radiations are given, elements and units used in radiation protection are reminded in tables. A part of this article is devoted to how to use radiation protection in a nuclear analysis laboratory. (N.C.)

  10. Effective protection of biological membranes against photo-oxidative damage: Polymeric antioxidant forming a protecting shield over the membrane.

    Science.gov (United States)

    Mertins, Omar; Mathews, Patrick D; Gomide, Andreza B; Baptista, Mauricio S; Itri, Rosangela

    2015-10-01

    We have prepared a chitosan polymer modified with gallic acid in order to develop an efficient protection strategy biological membranes against photodamage. Lipid bilayers were challenged with photoinduced damage by photosensitization with methylene blue, which usually causes formation of hydroperoxides, increasing area per lipid, and afterwards allowing leakage of internal materials. The damage was delayed by a solution of gallic acid in a concentration dependent manner, but further suppressed by the polymer at very low concentrations. The membrane of giant unilamellar vesicles was covered with this modified macromolecule leading to a powerful shield against singlet oxygen and thus effectively protecting the lipid membrane from oxidative stress. The results have proven the discovery of a promising strategy for photo protection of biological membranes. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Bonderenko self-shielded cross sections and multiband parameters derived from the LLL Evaluated-Nuclear-Data Library (ENDL)

    International Nuclear Information System (INIS)

    Cullen, D.E.

    1978-01-01

    Bonderenko self-shielded cross sections and multiband parameters from the Lawrence Livermore Laboratory Evaluated-Nuclear-Data Library (ENDL) as of July 4, 1978 are presented. These data include total, elastic, capture, and fission cross sections in the TART 175 group structure. Multiband parameters are listed. Bonderenko self-shielded cross section and the multiband parameters are presented on microfiche

  12. A Protective Eye Shield for Prevention of Media Opacities during Small Animal Ocular Imaging

    Science.gov (United States)

    Bell, Brent A.; Kaul, Charles; Hollyfield, Joe G.

    2014-01-01

    Optical coherence tomography (OCT), scanning laser ophthalmoscopy (SLO) and other non-invasive imaging techniques are increasingly used in eye research to document disease-related changes in rodent eyes. Corneal dehydration is a major contributor to the formation of ocular opacities that can limit the repeated application of these techniques to individual animals. General anesthesia is usually required for imaging, which is accompanied by the loss of the blink reflex. As a consequence, the tear film cannot be maintained, drying occurs and the cornea becomes dehydrated. Without supplemental hydration, structural damage to the cornea quickly follows. Soon thereafter, anterior lens opacities can also develop. Collectively these changes ultimately compromise image quality, especially for studies involving repeated use of the same animal over several weeks or months. To minimize these changes, a protective shield was designed for mice and rats that prevent ocular dehydration during anesthesia. The eye shield, along with a semi-viscous ophthalmic solution, is placed over the corneas as soon as the anesthesia immobilizes the animal. Eye shields are removed for only the brief periods required for imaging and then reapplied before the fellow eye is examined. As a result, the corneal surface of each eye is exposed only for the time required for imaging. The device and detailed methods described here minimize the corneal and lens changes associated with ocular surface desiccation. When these methods are used consistently, high quality images can be obtained repeatedly from individual animals. PMID:25245081

  13. Fire protection in nuclear power plants

    International Nuclear Information System (INIS)

    1979-01-01

    The Safety Guide gives design and some operational guidance for protection from fire and fire-related explosions in nuclear power plants (NPP). It confines itself to fire protection of items important to safety, leaving the aspects of fire protection not related to safety in NPP to be decided upon the basis of the national practices and regulations

  14. Velcro-Like System Used to Fix a Protective Faecal Shield on Weevil Larvae.

    Science.gov (United States)

    Skuhrovec, Jiří; Stejskal, Robert; Trnka, Filip; di Giulio, Andrea

    2017-01-01

    The last instar larva and pupa of Eucoeliodes mirabilis (A. Villa & G. B. Villa, 1835) (Curculionidae: Ceutorhynchini) are described using drawings and SEM images and are compared and keyed with already described larvae of 58 other ceutorhynchinae taxa. The larval body has an effective combination of morphological adaptations that assist a unique biological defensive strategy. All larval stages of E. mirabilis feed ectophytically on leaves of Euonymus europaeus L. (Celastraceae), and the larval body is covered with a thick faecal shield. The fixation of this protective shield on the larval back is performed by a peculiar dorsal microsculpture composed of a dense carpet of microtrichia on the thorax and abdomen, which serves effectively as a velcro system. Because of this strategy, macrosetae on the larval and pupal body of E. mirabilis are completely reduced. Larvae of E. mirabilis also have distinct morphological adaptations for protecting the spiracles against intrusion of faeces and avoiding occlusion of the tracheal system: a) microtrichia around spiracles are slightly shorter, distinctly stronger and are arranged with high-density and in clusters and b) spiracles are protected by an external safety valve. This strategy of E. mirabilis larvae is unique, although somewhat similar to that of Criocerinae and Blepharida-group leave beetles (Galerucinae) (both Coleoptera: Chrysomelidae), but with distinctly different morphological adaptations.

  15. Nuclear Rocket Test Facility Decommissioning Including Controlled Explosive Demolition of a Neutron-Activated Shield Wall

    International Nuclear Information System (INIS)

    Michael Kruzic

    2007-01-01

    Located in Area 25 of the Nevada Test Site, the Test Cell A Facility was used in the 1960s for the testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program. The facility was decontaminated and decommissioned (D and D) in 2005 using the Streamlined Approach For Environmental Restoration (SAFER) process, under the Federal Facilities Agreement and Consent Order (FFACO). Utilities and process piping were verified void of contents, hazardous materials were removed, concrete with removable contamination decontaminated, large sections mechanically demolished, and the remaining five-foot, five-inch thick radiologically-activated reinforced concrete shield wall demolished using open-air controlled explosive demolition (CED). CED of the shield wall was closely monitored and resulted in no radiological exposure or atmospheric release

  16. Quantum shielding effects on the Gamow penetration factor for nuclear fusion reaction in quantum plasmas

    Science.gov (United States)

    Lee, Myoung-Jae; Jung, Young-Dae

    2017-01-01

    The quantum shielding effects on the nuclear fusion reaction process are investigated in quantum plasmas. The closed expression of the classical turning point for the Gamow penetration factor in quantum plasmas is obtained by the Lambert W-function. The closed expressions of the Gamow penetration factor and the cross section for the nuclear fusion reaction in quantum plasmas are obtained as functions of the plasmon energy and the relative kinetic energy by using the effective interaction potential with the WKB analysis. It is shown that the influence of quantum screening suppresses the Sommerfeld reaction factor. It is also shown that the Gamow penetration factor increases with an increase of the plasmon energy. It is also shown that the quantum shielding effect enhances the deuterium formation by the proton-proton reaction in quantum plasmas. In addition, it is found that the energy dependences on the reaction cross section and the Gamow penetration factor are more significant in high plasmon-energy domains.

  17. Radiation protection on nuclear medicine services

    International Nuclear Information System (INIS)

    Anon

    2000-01-01

    Nuclear medicine is a sector of the medicine that studies and applies radionuclide in diagnosis and therapy. Nuclear medicine is a very specific area of the medicine, making use of non-sealed radioactive sources which are prescribed to the patient orally or are injected. Special procedures in radiation protection are required in nuclear medicine to manipulate these kind of sources and to produce technetium-99m through molybdenum generator. The present paper addresses the them radiation protection in a Nuclear Medicine Department (NMD), showing the main requirements of the CNEN- National Commission of Nuclear Energy and the Public Health. Radiation protection procedures adopted in assembling a NMD, as well the daily techniques for monitoring and for individual dosimetry are discussed. Past and present analyses in a level of radiation protection are presented. (author)

  18. Nuclear-industry employee protection provisions of federal law

    International Nuclear Information System (INIS)

    Fidell, E.R.; Marcoux, W.C.

    1982-01-01

    Legislation enacted by Congress in 1978 to provide protection for those employed in the construction or operation of civil nuclear projects who express concerns to employers or others about the propriety of procedures in their places of employment from the standpoint of safety is summarized. The authors describe some recent and anticipated developments in the implementation of the law and offer practical suggestions for the avoidance of particular problems under the law. They counsel that the prudent utility company or other firm involved with nuclear energy will see the statute as another reason for facilitating the flow of bona fide safety concerns rather than as a vehicle for the expression of generalized complaints by malcontents and a convenient shield for substandard performers in the work force

  19. Evaluation of serpentine ore as a nuclear shielding material using gas chromatographic techniques

    International Nuclear Information System (INIS)

    Singh, B.N.; Unnikrishnan, E.K.; Kumar, Sangita D.

    2007-01-01

    Serpentine ore mixed with cement has been recognized as a candidate shielding material for use in nuclear reactors because of its many desirable properties. Therefore the assessment of serpentine ore for release of volatile gases during exposure to elevated temperatures, irradiation and changes in chemical composition, is essential. The present paper deals with the studies on the serpentine ores using gas chromatography and combustion gas chromatographic techniques. (author)

  20. Development of point Kernel radiation shielding analysis computer program implementing recent nuclear data and graphic user interfaces

    International Nuclear Information System (INIS)

    Kang, S.; Lee, S.; Chung, C.

    2002-01-01

    There is an increasing demand for safe and efficient use of radiation and radioactive work activity along with shielding analysis as a result the number of nuclear and conventional facilities using radiation or radioisotope rises. Most Korean industries and research institutes including Korea Power Engineering Company (KOPEC) have been using foreign computer programs for radiation shielding analysis. Korean nuclear regulations have introduced new laws regarding the dose limits and radiological guides as prescribed in the ICRP 60. Thus, the radiation facilities should be designed and operated to comply with these new regulations. In addition, the previous point kernel shielding computer code utilizes antiquated nuclear data (mass attenuation coefficient, buildup factor, etc) which were developed in 1950∼1960. Subsequently, the various nuclear data such mass attenuation coefficient, buildup factor, etc. have been updated during the past few decades. KOPEC's strategic directive is to become a self-sufficient and independent nuclear design technology company, thus KOPEC decided to develop a new radiation shielding computer program that included the latest regulatory requirements and updated nuclear data. This new code was designed by KOPEC with developmental cooperation with Hanyang University, Department of Nuclear Engineering. VisualShield is designed with a graphical user interface to allow even users unfamiliar to radiation shielding theory to proficiently prepare input data sets and analyzing output results

  1. The Physical Protection of Nuclear Material and Nuclear Facilities

    International Nuclear Information System (INIS)

    1999-08-01

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international co-operation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and nuclear materials, particularly when such materials are transported across national frontiers

  2. The Physical Protection of Nuclear Material and Nuclear Facilities

    International Nuclear Information System (INIS)

    1999-06-01

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international co-operation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and nuclear materials, particularly when such materials are transported across national frontiers [es

  3. The Physical Protection of Nuclear Material and Nuclear Facilities

    International Nuclear Information System (INIS)

    1999-06-01

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international co-operation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and nuclear materials, particularly when such materials are transported across national frontiers

  4. Active shield technology for space craft protection revisited in new laboratory results and analysis

    Science.gov (United States)

    Bamford, R.; Gibson, K. J.; Thornton, A. T.; Bradford, J.; Bingham, R.; Gargate, L.; Silva, L. O.; Fonseca, R. A.; Hapgood, M.; Norberg, C.; Todd, T.; Stamper, R.

    2009-04-01

    Energetic ions in the solar wind plasma are a known hazard to both spacecraft electronics and to astronaut's health. Of primary concern is the exposure to keV--MeV protons on manned space flights to the Moon and Mars that extend over long periods of time. Attempts to protect the spacecraft include active shields that are reminiscent of Star Trek "deflector" shields. Here we describe a new experiment to test the shielding concept of a dipole-like magnetic field and plasma, surrounding the spacecraft forming a "mini magnetosphere". Initial laboratory experiments have been conducted to determine the effectiveness of a magnetized plasma barrier to be able to expel an impacting, low beta, supersonic flowing energetic plasma representing the Solar Wind. Optical and Langmuir probe data of the plasma density, the plasma flow velocity, and the intensity of the dipole field clearly show the creation of a narrow transport barrier region and diamagnetic cavity virtually devoid of energetic plasma particles. This demonstrates the potential viability of being able to create a small "hole" in a Solar Wind plasma, of the order of the ion Larmor orbit width, in which an inhabited spacecraft could reside in relative safety. The experimental results have been quantitatively compared to a 3D particle-in-cell ‘hybrid' code simulation that uses kinetic ions and fluid electrons, showing good qualitative agreement and excellent quantitative agreement. Together the results demonstrate the pivotal role of particle kinetics in determining generic plasma transport barriers. [1] [1] R Bamford et al., "The interaction of a flowing plasma with a dipole magnetic field: measurements and modelling of a diamagnetic cavity relevant to spacecraft protection." 2008 Plasma Phys. Control. Fusion 50 124025 (11pp) doi: 10.1088/0741-3335/50/12/124025

  5. Bragg Curve, Biological Bragg Curve and Biological Issues in Space Radiation Protection with Shielding

    Science.gov (United States)

    Honglu, Wu; Cucinotta, F.A.; Durante, M.; Lin, Z.; Rusek, A.

    2006-01-01

    The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the major protection to astronauts from harmful exposure. Unlike low-LET gamma or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure. Since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak, the Bragg curve does not necessarily represent the biological damage along the particle traversal since biological effects are influenced by the track structure of both primary and secondary particles. Therefore, the biological Bragg curve is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. To achieve a Bragg curve distribution, we exposed cells to energetic heavy ions with the beam geometry parallel to a monolayer of fibroblasts. Qualitative analyses of gamma-H2AX fluorescence, a known marker of DSBs, indicated increased clustering of DNA damage before the Bragg peak, enhanced homogenous distribution at the peak, and provided visual evidence of high linear energy transfer (LET) particle traversal of cells beyond the Bragg peak. A quantitative biological response curve generated for micronuclei (MN) induction across the Bragg curve did not reveal an increased yield of MN at the location of the Bragg peak. However, the ratio of mono-to bi-nucleated cells, which indicates inhibition in cell progression, increased at the Bragg peak location. These results, along with other biological concerns, show that space radiation protection with shielding can be a complicated issue.

  6. Nuclear energy for environmental protection

    International Nuclear Information System (INIS)

    Souza, Jair Albo Marques de

    1992-01-01

    In 1990 nuclear energy supplied about 17% of the total electric power produced in the world, what makes it the third most used power source after coal and hydropower. In this paper the advantages of using nuclear power for generating large quantities of electric power are presented

  7. Advanced physical protection systems for nuclear materials

    International Nuclear Information System (INIS)

    Jones, O.E.

    1975-10-01

    Because of the increasing incidence of terrorism, there is growing concern that nuclear materials and facilities need improved physical protection against theft, diversion, or sabotage. Physical protection systems for facilities or transportation which have balanced effectiveness include information systems, access denial systems, adequate and timely response, recovery capability, and use denial methods for despoiling special nuclear materials (SNM). The role of these elements in reducing societal risk is described; however, it is noted that, similar to nuclear war, the absolute risks of nuclear theft and sabotage are basically unquantifiable. Sandia Laboratories has a major Energy Research and Development Administration (ERDA) role in developing advanced physical protection systems for improving the security of both SNM and facilities. These activities are surveyed. A computer simulation model is being developed to assess the cost-effectiveness of alternative physical protection systems under various levels of threat. Improved physical protection equipment such as perimeter and interior alarms, secure portals, and fixed and remotely-activated barriers is being developed and tested. In addition, complete prototype protection systems are being developed for representative nuclear facilities. An example is shown for a plutonium storage vault. The ERDA safe-secure transportation system for highway shipments of all significant quantities of government-owned SNM is described. Adversary simulation as a tool for testing and evaluating physical protection systems is discussed. A list of measures is given for assessing overall physical protection system performance. (auth)

  8. Advanced physical protection systems for nuclear materials

    International Nuclear Information System (INIS)

    Jones, O.E.

    1976-01-01

    Because of the increasing incidence of terrorism, there is growing concern that nuclear materials and facilities need improved physical protection against theft, diversion, or sabotage. Physical protection systems for facilities or transportation which have balanced effectiveness include information systems, access denial systems, adequate and timely response, recovery capability, and use denial methods for despoiling special nuclear materials (SNM). The role of these elements in reducing societal risk is described; however, it is noted that, similar to nuclear war, the absolute risks of nuclear theft and sabotage are basically unquantifiable. Sandia Laboratories has a major US Energy Research and Development Administration (ERDA) role in developing advanced physical protection systems for improving the security of both SNM and facilities. These activities are surveyed in this paper. A computer simulation model is being developed to assess the cost-effectiveness of alternative physical protection systems under various levels of threat. Improved physical protection equipment such as perimeter and interior alarms, secure portals, and fixed and remotely activated barriers is being developed and tested. In addition, complete prototype protection systems are being developed for representative nuclear facilities. An example is shown for a plutonium storage vault. The ERDA safe-secure transportation system for highway shipments of all significant quantities of government-owned SNM is described. Adversary simulation as a tool for testing and evaluating physical protection systems is discussed. Finally, a list of measures is given for assessing overall physical protection system performance. (author)

  9. The Physical Protection of Nuclear Material

    International Nuclear Information System (INIS)

    1993-01-01

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international cooperation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and materials, particularly when such materials are transported across national frontiers

  10. The Physical Protection of Nuclear Material

    International Nuclear Information System (INIS)

    1993-09-01

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international cooperation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and materials, particularly when such materials are transported across national frontiers [es

  11. The Physical Protection of Nuclear Material

    International Nuclear Information System (INIS)

    1993-09-01

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international cooperation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and materials, particularly when such materials are transported across national frontiers [fr

  12. The Physical Protection of Nuclear Material

    International Nuclear Information System (INIS)

    1993-09-01

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international cooperation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and materials, particularly when such materials are transported across national frontiers

  13. Integrated nuclear and radiation protection systems

    International Nuclear Information System (INIS)

    Oprea, I.; Oprea, M.; Stoica, V.; Cerga, V.; Pirvu, V.; Badea, E.

    1993-01-01

    A multifunctional radiation monitoring equipment, flexible and capable to meet virtually environmental radiation monitoring, activity measurement and computational requirements, for nuclear laboratories has been designed. It can be used as a radiation protection system, for radionuclide measurement in isotope laboratories, nuclear technology, health physics and nuclear medicine, nuclear power stations and nuclear industry. The equipment is able to measure, transmit and record gamma dose rate and isotope activities. Other parameters and functions are optionally available, such as: self-contained alarm level, system self-test, dose integrator, syringe volume calculation for a given dose corrected for decay, calibration factor, 99 Mo assays performing and background subtraction

  14. Nuclear power for environmental protection

    International Nuclear Information System (INIS)

    Souza Marques de, J.A.; Bennett, L.L.

    1989-09-01

    Nuclear power does not produce CO 2 or other greenhouse gases, and also does not produce any SO 2 , NO x or other gases which contribute to acid rain. These characteristics of nuclear power are especially important in comparison to coal-fired generation of electricity. As an example, in comparison with a coal-fired power plant of the same size, with abatement systems, a 1300 MW(e) nuclear power plant eliminates annually emissions to the air of about: 2000 t of particulates; 8.5 million t of CO 2 : 12,000 t of SO 2 ; and 6,000 t of NO x , the precise quantities being dependent on coal quality, power plant design and thermal efficiency, and on the effectiveness of the abatement systems. Opponents of nuclear power concede these facts, but argue that nuclear power is such a small part of the world energy balance that it is insignificant to the big issue of CO 2 . This is hardly correct. Today, 16% of the world's electricity (and 5% of the world's total primary energy) is generated using nuclear power. If this electricity were to have been generated using coal, it would have resulted in about 1600 million tons of CO 2 annually. This is 8% of the 20,000 million tons of CO 2 now emitted annually from the burning of fossil fuels, an amount which the Toronto Conference proposed should be cut by 20% up to the year 2005. A further major difference in the two energy systems is that the relatively smaller amount of nuclear wastes is fully isolated from the environment. In addition to discussing the global contributions of nuclear power to environmental improvement, the paper presents actual results achieved in a number of countries, demonstrating the positive contribution which nuclear power has made to reducing the environmental impacts of electricity production. 7 figs, 12 tabs

  15. Physical protection of nuclear operational units

    International Nuclear Information System (INIS)

    1981-07-01

    The general principles of and basic requirements for the physical protection of operational units in the nuclear field are established. They concern the operational units whose activities are related with production, utilization, processing, reprocessing, handling, transport or storage of materials of interest for the Brazilian Nuclear Program. (I.C.R.) [pt

  16. Nuclear emergency protection. Today and tomorrow

    International Nuclear Information System (INIS)

    Buettner, Jens Uwe

    2016-01-01

    The state of affairs of the nuclear emergency protection at accidents in connection with the use of nuclear power, at incidents with dangerous radiation sources as well as in case of criminal use of radioactive substances is presented. Moreover, the organization and the responsibilities as well as the preparation and realization of emergency training are considered and commented.

  17. Early test facilities and analytic methods for radiation shielding: Proceedings

    International Nuclear Information System (INIS)

    Ingersoll, D.T.; Ingersoll, J.K.

    1992-11-01

    This report represents a compilation of eight papers presented at the 1992 American Nuclear Society/European Nuclear Society International Meeting. The meeting is of special significance since it commemorates the fiftieth anniversary of the first controlled nuclear chain reaction. The papers contained in this report were presented in a special session organized by the Radiation Protection and Shielding Division in keeping with the historical theme of the meeting. The paper titles are good indicators of their content and are: (1) The origin of radiation shielding research: The Oak Ridge experience, (2) Shielding research at the hanford site, (3) Aircraft shielding experiments at General Dynamics Fort Worth, 1950-1962, (4) Where have the neutrons gone?, a history of the tower shielding facility, (5) History and evolution of buildup factors, (6) Early shielding research at Bettis atomic power laboratory, (7) UK reactor shielding: then and now, (8) A very personal view of the development of radiation shielding theory

  18. Radiation protection in nuclear medicine

    International Nuclear Information System (INIS)

    Chougule, Arun

    2014-01-01

    The branch of medical science that utilizes the nuclear properties of the radioactivity and stable nuclides to make diagnostic evaluation of anatomical and/or physiological conditions of the body and provide therapy with unsealed radioactive sources is called Nuclear Medicine (NM). The use of unsealed radionuclides in medicine is increasing throughout the world for diagnosis and treatment. As per UNSCEAR report more than 6 million nuclear medicine procedures are conducted in a year. However we know that radiation is double edged sword and if not used carefully will be harmful to patient as well as staff and therefore a nuclear medicine procedure should be undertaken only after proper justification and optimization. Nuclear medicine procedures are different than the X-ray diagnostic procedures as in NM, radioisotope is administered to patient and patient becomes radioactive. The NM staff is involved in unpacking radioactive material, activity measurements, storage of sources, internal transports of sources, preparation of radiopharmaceuticals, administration of radiopharmaceutical, examination of the patient, care of the radioactive patient, handling of radioactive waste and therefore receives radiation dose. This talk will discuss the various steps for radiation safety of patient, staff and public during Nuclear Medicine procedures so as to implementing the ALARA concept. (author)

  19. Radiation protection in nuclear reactors

    International Nuclear Information System (INIS)

    El-Ashkar, Mohamed

    2008-01-01

    Full text: People are exposed to ionizing radiation in many different forms: cosmic rays that penetrate earth atmosphere or radiation from soil and mineral resources are natural forms of ionizing radiation. Other forms are produced artificially using radioactive materials for various beneficial applications in medicine, industry and other fields. The greatest concerns about ionizing radiation are tied to its potential health effects and a system of radiation protection has been developed to protect people from harmful radiation. The promotion of radiation protection is one of the International Atomic Energy Agency main activities. Radiation protection concerns the protection of workers, members of public, and patients undergoing diagnosis and therapy against the harmful effects of ionizing radiation. The report covers the responsibility of radiation protection officer in Egypt Second Research Reactor (ETRR-2) in Inshas - Egypt, also presents the protection against ionizing radiation from external sources, including types of radiation, sources of radiation (natural - artificial), and measuring units of dose equivalent rate. Also covers the biological effects of ionizing radiation, personal monitoring and radiation survey instruments and safe transport of radioactive materials. The report describes the Egypt Second Research Reactor (ETRR-2), the survey instruments used, also presents the results obtained and gave a relations between different categories of data. (author)

  20. Three-dimensional coupled Monte Carlo-discrete ordinates computational scheme for shielding calculations of large and complex nuclear facilities

    International Nuclear Information System (INIS)

    Chen, Y.; Fischer, U.

    2005-01-01

    Shielding calculations of advanced nuclear facilities such as accelerator based neutron sources or fusion devices of the tokamak type are complicated due to their complex geometries and their large dimensions, including bulk shields of several meters thickness. While the complexity of the geometry in the shielding calculation can be hardly handled by the discrete ordinates method, the deep penetration of radiation through bulk shields is a severe challenge for the Monte Carlo particle transport technique. This work proposes a dedicated computational scheme for coupled Monte Carlo-Discrete Ordinates transport calculations to handle this kind of shielding problems. The Monte Carlo technique is used to simulate the particle generation and transport in the target region with both complex geometry and reaction physics, and the discrete ordinates method is used to treat the deep penetration problem in the bulk shield. The coupling scheme has been implemented in a program system by loosely integrating the Monte Carlo transport code MCNP, the three-dimensional discrete ordinates code TORT and a newly developed coupling interface program for mapping process. Test calculations were performed with comparison to MCNP solutions. Satisfactory agreements were obtained between these two approaches. The program system has been chosen to treat the complicated shielding problem of the accelerator-based IFMIF neutron source. The successful application demonstrates that coupling scheme with the program system is a useful computational tool for the shielding analysis of complex and large nuclear facilities. (authors)

  1. Shields calculations for teletherapy equipment. Regulatory approach of the National Center of Nuclear Safety

    International Nuclear Information System (INIS)

    Fuente P, A. de la; Dumenigo G, C.; Quevedo G, J.R.; Lopez F, Y.

    2006-01-01

    The evaluation of applications of construction licenses for the new services of radiotherapy has occupied a significant space in the activity developed by the National Center of Nuclear Safety (CNSN) in the last 2 years. Presently work the experiences of the authors in the evaluation of the required shield for the local where cobalt therapy equipment and lineal accelerators of medical use are used its are exposed, the practical problems detected are approached during the application of the methodologies recommended in both cases and its are discussed which have been the suppositions of items accepted by the Regulatory Authority for the realization of these shield calculations. The accumulated experience allows to assure that the realistic application of the item data and the rational use of the engineering logic makes possible to design local for radiotherapy equipment that fulfill the established dose restrictions in the in use legislation in Cuba, without it implies an excessive expense of construction materials. (Author)

  2. Programmed system for nuclear power plant protection

    International Nuclear Information System (INIS)

    Jover, Pierre.

    1980-06-01

    The progress in the field of microprocessors and large scale integration circuits, have incited to introduce this new technologies into nuclear power plant protection system. The hardware and software design principles are briefly listed; then, a quad-redundant protection system for 1300 MWe PWR, developed in France is described [fr

  3. Relativistic heavy-atom effects on heavy-atom nuclear shieldings

    Science.gov (United States)

    Lantto, Perttu; Romero, Rodolfo H.; Gómez, Sergio S.; Aucar, Gustavo A.; Vaara, Juha

    2006-11-01

    The principal relativistic heavy-atom effects on the nuclear magnetic resonance (NMR) shielding tensor of the heavy atom itself (HAHA effects) are calculated using ab initio methods at the level of the Breit-Pauli Hamiltonian. This is the first systematic study of the main HAHA effects on nuclear shielding and chemical shift by perturbational relativistic approach. The dependence of the HAHA effects on the chemical environment of the heavy atom is investigated for the closed-shell X2+, X4+, XH2, and XH3- (X =Si-Pb) as well as X3+, XH3, and XF3 (X =P-Bi) systems. Fully relativistic Dirac-Hartree-Fock calculations are carried out for comparison. It is necessary in the Breit-Pauli approach to include the second-order magnetic-field-dependent spin-orbit (SO) shielding contribution as it is the larger SO term in XH3-, XH3, and XF3, and is equally large in XH2 as the conventional, third-order field-independent spin-orbit contribution. Considering the chemical shift, the third-order SO mechanism contributes two-thirds of the difference of ˜1500ppm between BiH3 and BiF3. The second-order SO mechanism and the numerically largest relativistic effect, which arises from the cross-term contribution of the Fermi contact hyperfine interaction and the relativistically modified spin-Zeeman interaction (FC/SZ-KE), are isotropic and practically independent of electron correlation effects as well as the chemical environment of the heavy atom. The third-order SO terms depend on these factors and contribute both to heavy-atom shielding anisotropy and NMR chemical shifts. While a qualitative picture of heavy-atom chemical shifts is already obtained at the nonrelativistic level of theory, reliable shifts may be expected after including the third-order SO contributions only, especially when calculations are carried out at correlated level. The FC/SZ-KE contribution to shielding is almost completely produced in the s orbitals of the heavy atom, with values diminishing with the principal

  4. Physical protection of nuclear installations

    International Nuclear Information System (INIS)

    Toepfer, K.

    1989-01-01

    This contribution investigates the possible danger and the legal basis of physical protection and explains the current, integrated system provided for, as well as the underlying possible scenarios of an assault: (1) by a violent crowd of aggressors outside the installation, (2) by a small group of aggressors outside the installation, (3) by a person allowed to enter (internal assault). The physical protection system supplements the internal safety measures to enhance protection against hypothetical and possible acts of terrorism or other criminal assault. The system covers external and internal controlled areas, access monitoring, physical protection control room and service, security checks of the personnel, and activities to disclose sabotage. Some reflections on the problem field between security controls and the constitutional state conclude this contribution. (orig./HSCH) [de

  5. Production of a datolite-based heavy concrete for shielding nuclear reactors and megavoltage radiotherapy rooms

    International Nuclear Information System (INIS)

    Mortazavi, S. M. J.; Mosleh-Shirazi, M.A.; Baradaran-Ghahfarokhi, M.; Siavashpour, Z.; Farshadi, A.; Ghafoori, M.; Shahvar, A.

    2010-01-01

    Biological shielding of nuclear reactors has always been a great concern and decreasing the complexity and expense of these installations is of great interest. In this study, we used datolite and galena minerals for production of a high performance heavy concrete. Materials and Methods: Datolite and galena minerals which can be found in many parts of Iran were used in the concrete mix design. To measure the gamma radiation attenuation of the Datolite and galena concrete samples, they were exposed to both narrow and wide beams of gamma rays emitted from a cobalt-60 radiotherapy unit. An Am-Be neutron source was used for assessing the shielding properties of the samples against neutrons. To test the compression strengths, both types of concrete mixes (Datolite and galena and ordinary concrete) were investigated. Results: The concrete samples had a density of 4420-4650 kg/m 3 compared to that of ordinary concrete (2300-2500 kg/m 3 ) or barite high density concrete (up to 3500 kg/m 3 ). The measured half value layer thickness of the Datolite and galena concrete samples for cobalt-60 gamma rays was much less than that of ordinary concrete (2.56 cm compared to 6.0 cm). Furthermore, the galena concrete samples had a significantly higher compressive strength as well as 20% more neutron absorption. Conclusion: The Datolite and galena concrete samples showed good shielding/engineering properties in comparison with other reported samples made, using high-density materials other than depleted uranium. It is also more economic than the high-density concretes. Datolite and galena concrete may be a suitable option for shielding nuclear reactors and megavoltage radiotherapy rooms.

  6. Radiation protection in nuclear energy. V.1

    International Nuclear Information System (INIS)

    1988-01-01

    The conference was convened to provide a forum for the exchange of international views on the principles of radiation protection for regulators and practitioners, to highlight issues of current importance, to examine the problems encountered in applying the principles of radiation protection, and, where possible, to identify generic solutions. A special session entitled ''The dose-response relationship: implications for nuclear energy'', and a panel on ''Radiation protection education and training'' were included in the conference programme. Refs, figs and tabs

  7. Concrete radiation shielding

    International Nuclear Information System (INIS)

    Kaplan, M.F.

    1989-01-01

    The increased use of nuclear energy has given rise to a growth in the amount of artificially produced radiation and radioactive materials. The design and construction of shielding to protect people, equipment and structures from the effects of radiation has never been more important. Experience has shown that concrete is an effective, versatile and economical material for the construction of radiation shielding. This book provides information on the principles governing the interaction of radiation with matter and on relevant nuclear physics to give the engineer an understanding of the design and construction of concrete shielding. It covers the physical, mechanical and nuclear properties of concrete; the effects of elevated temperatures and possible damage to concrete due to radiation; basic procedures for the design of concrete radiation shields and finally the special problems associated with their construction and cost. Although written primarily for engineers concerned with the design and construction of concrete shielding, the book also reviews the widely scattered data and information available on this subject and should therefore be of interest to students and those wishing to research further in this field. (author)

  8. Lightning protection design of nuclear power plants. KTA safety code, version 6/99

    International Nuclear Information System (INIS)

    1999-06-01

    This KTA safety code does not cover calculation methods for determination of lightning-induced voltage inputs to control room systems within the reactor building, as the literature presents a variety of applicable methods, which however cannot be directly applied to any power plant, due to the great diversity of geometries of the electrical systems and control room systems in nuclear power plants. Compliance with the design requirements of this safety code for shielding of buildings, and installation and shielding of cables, can be considered to offer the appropriate protection. (orig./CB) [de

  9. Radiation shielding at interim storage facility for CANDU-type nuclear spent fuel

    International Nuclear Information System (INIS)

    Mateescu, S.; Radu, M. Pantazi D.; Stanciu, M.

    1997-01-01

    Technical measures in radiological protection are taken in the interim storage facility design to ensure that, during normal operation, exposures of workers and members of public to ionizing radiation are limited to levels lower than regulatory limits. The spent fuel storage design provides for radiation exposure to be as low as reasonable achievable (ALARA principles). The evaluation of radiation shields includes the most conservative provisions: - all locations which may contain spent fuel are full; - the spent fuel has reached the maximum burnup; - the post irradiation cooling period should be the minimum reasonable; - equipment for handling contains the maximum amount of spent fuel. Radiation shields should ensure that external radiation fields do not exceed limits accepted by the Regulatory Body Module. The evaluation has been performed with two computer codes, QAD-5K and MICROSHIELD-4. (authors)

  10. Radiation protection programme for nuclear gauges

    International Nuclear Information System (INIS)

    Muzongomerwa, A.

    2014-04-01

    Ionizing radiation including the use of nuclear gauges can be very hazardous to humans and steps must be taken to minimize the risks so as to prevent deterministic effects and limiting chances for stochastic effects. The availability of a Radiation Protection Programme and its effective implementation ensures appropriate safety and security provisions for sealed radiation sources and promotes a safety culture within a facility that utilizes these sources. This study aims at establishing a guide on the radiation protection programme in nuclear gauges that comply with national requirements derived from current international recommendations. Elements that form part of a radiation protection programme are covered in detail as well as recommendations. The overall objective is to protect people (operators and the public) and the environment from the harmful effects of these sources if they are not properly controlled. Nuclear gauges for well logging and X-ray based gauges are outside the scope of this study. (au)

  11. Fabrication of indigenous lead-free low cost bilayer radiation protective apron and dosimetric analysis for effective shielding

    International Nuclear Information System (INIS)

    Senthilkumar, S.

    2014-01-01

    Protective aprons play a key role in the radiation protection of personnel in radiology departments. They are worn in examination rooms during radiological examinations and their specific function is to provide shielding against secondary radiation. Practically, they are used for a variety of diagnostic imaging procedures including angiography, fluoroscopy, mobiles and theatre, and are designed to shield approximately 75% of radiosensitive red bone marrow. For many years, the protective aprons play a key role in the radiation protection of personnel in imaging departments was made of lead. However, lead garments must be treated as hazardous waste for disposal and are heavy, causing back strain and other orthopedic problems for those who must wear them for long periods of time. They are worn in examination rooms during radiological examinations and their specific function is to provide shielding against secondary radiation. Originally, protective aprons consisted of lead-impregnated vinyl or rubber with a shielding equivalent given in millimetres of lead. The main purpose of this study was to fabricate light weight low cost non lead based bilayered radiation protective aprons

  12. Evaluation of nuclear data for radiation shielding by model calculations and international co-operation aspects

    International Nuclear Information System (INIS)

    Canetta, E.; Maino, G.; Menapace, E.

    2001-01-01

    The matter is reviewed, also following previous discussions at ICRS-9, concerning evaluation and related theoretical activities on nuclear data for radiation shielding within the framework of international co-operation initiatives, according to recognised needs and priorities. Both cross-section data.- for reactions induced by neutrons and photons - and nuclear structure data have been considered. In this context, main contributions and typical results are presented from theoretical and evaluation activities at the ENEA Applied Physics Division, especially concerning neutron induced reaction data up to 20 MeV and photonuclear reaction data such as photon absorption and (gamma,n) cross-sections. Relevant aspects of algebraic nuclear models and of evaporation and pre-equilibrium models are discussed. (authors)

  13. Temperature distribution due to the heat generation in nuclear reactor shielding

    International Nuclear Information System (INIS)

    Torres, L.M.R.

    1985-01-01

    A study is performed for calculating nuclear heating due to the interaction of neutrons and gamma-rays with matter. Modifications were implemented in the ANISN and DOT 3.5 codes, that solve the transport equation using the discrete ordinate method, in one two-dimensions respectively, to include nuclear heating calculations in these codes. In order to determine the temperature distribution, using the finite difference method, a numerical model was developed for solving the heat conduction equation in one-dimension, in plane, cylindrical and spherical geometries, and in two-dimensions, X-Y and R-Z geometries. Based on these models, computer programs were developed for calculating the temperature distribution. Tests and applications of the implemented modifications were performed in problems of nuclear heating and temperature distribution due to radiation energy deposition in fission and fusion reactor shields. (Author) [pt

  14. Nuclear reactor safety protection device

    International Nuclear Information System (INIS)

    Okido, Fumiyasu; Noguchi, Atomi; Matsumiya, Shoichi; Furusato, Ken-ichiro; Arita, Setsuo.

    1994-01-01

    The device of the present invention extremely reduces a probability of causing unnecessary scram of a nuclear reactor. That is, four control devices receive signals from each of four sensors and output four trip signals respectively in a quardruplicated control device. Each of the trip signals and each of trip signals via a delay circuit are inputted to a logical sum element. The output of the logical sum circuit is inputted to a decision of majority circuit. The decision of majority circuit controls a scram pilot valve which conducts scram of the reactor by way of a solenoid coils. With such procedures, even if surge noises of a short pulse width are mixed to the sensor signals and short trip signals are outputted, there is no worry that the scram pilot valve is actuated. Accordingly, factors of lowering nuclear plant operation efficiency due to erroneous reactor scram can be reduced. (I.S.)

  15. Estimation of Shielding Thickness for a Prototype Department of Energy National Spent Nuclear Fuel Program Transport Cask

    Energy Technology Data Exchange (ETDEWEB)

    SANCHEZ,LAWRENCE C.; MCCONNELL,PAUL E.

    2000-07-01

    Preliminary shielding calculations were performed for a prototype National Spent Nuclear Fuel Program (NSNFP) transport cask. This analysis is intended for use in the selection of cask shield material type and preliminary estimate of shielding thickness. The radiation source term was modeled as cobalt-60 with radiation exposure strength of 100,000 R/hr. Cobalt-60 was chosen as a surrogate source because it simultaneous emits two high-energy gammas, 1.17 MeV and 1.33 MeV. This gamma spectrum is considered to be large enough that it will upper bound the spectra of all the various spent nuclear fuels types currently expected to be shipped within the prototype cask. Point-kernel shielding calculations were performed for a wide range of shielding thickness of lead and depleted uranium material. The computational results were compared to three shielding limits: 200 mrem/hr dose rate limit at the cask surface, 50 mR/hr exposure rate limit at one meter from the cask surface, and 10 mrem/hr limit dose rate at two meters from the cask surface. The results obtained in this study indicated that a shielding thickness of 13 cm is required for depleted uranium and 21 cm for lead in order to satisfy all three shielding requirements without taking credit for stainless steel liners. The system analysis also indicated that required shielding thicknesses are strongly dependent upon the gamma energy spectrum from the radiation source term. This later finding means that shielding material thickness, and hence cask weight, can be significantly reduced if the radiation source term can be shown to have a softer, lower energy, gamma energy spectrum than that due to cobalt-60.

  16. The design study of the JT-60SU device. No.8. Nuclear shielding and safety design

    Energy Technology Data Exchange (ETDEWEB)

    Miya, Naoyuki; Kikuchi, Mitsuru; Ushigusa, Kenkichi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment] [and others

    1998-03-01

    Results of nuclear shielding design study and safety analysis for the steady-state tokamak device JT-60SU are described. D-T operation (option) for two years is adopted in addition to ten years operation using deuterium. Design work has been done in accordance with general laws for radioisotopes handling in Japan as a guideline of safety evaluation, which is applied to the operation of present JT-60U device. Optimization of the shielding design for the device structure including vacuum vessel has been presented to meet with allowable limits of biological shielding determined in advance. It is shown that JT-60SU can be operated safely in the present JT-60 experimental building. It is planed to use 100g/year of tritium in D-T operation phase. A concept of multiple -barrier system is applied to the facility design to prevent propagation of tritium, in which the torus hall and the tritium removal room provide the tertiary confinement. From the design of atmosphere detritiation system for accidental tritium release, it is shown that tritium concentration level can be reduced to the allowable level after two weeks with reasonable compact size components. Safety assessment related to activation of coolant/air, and atmospheric tritium effluents are discussed. (author)

  17. Burst shield for a pressurized nuclear-reactor core and method of operating same

    International Nuclear Information System (INIS)

    Beine, B.; Schilling, F.

    1976-01-01

    A pressurized nuclear-reactor core stands on a base up from which extends a cylindrical side wall formed of a plurality of hollow iron castings held together by circumferential and longitudinal prestressed elements. A cylindrical space between this shield and the core serves for inspection of the core and is normally filled with cast-iron segmental slabs so that if the core bursts pieces thrown out do not acquire any dangerous kinetic energy before engaging the burst shield. The top of the shield is removably secured to the side so that it can be moved out of the way periodically for removal of the filler slabs and inspection of the core. An anchor on the upper end of each longitudinal prestressing element bears against a sleeve pressing against the uppermost side element, and a nut engageable with this anchor is engageable down over the top to hold it in place, removal of this nut leaving the element prestressed in the side wall. 11 claims, 16 drawing figures

  18. Can active proton interrogation find shielded nuclear threats at human-safe radiation levels?

    Energy Technology Data Exchange (ETDEWEB)

    Liew, Seth Van, E-mail: vanliew@gmail.com

    2017-05-21

    A new method of low-dose proton radiography is presented. The system is composed of an 800 MeV proton source, bending magnets, and compact detectors, and is designed for drive-through cargo scanning. The system has been simulated using GEANT4. Material identification algorithms and pixel sorting methods are presented that allow the system to perform imaging at doses low enough to scan passenger vehicles and people. Results are presented on imaging efficacy of various materials and cluttered cargoes. The identification of shielded nuclear materials at human-safe doses has been demonstrated.

  19. Shielding requirements for the transport of nuclear warhead components under decommissioning

    International Nuclear Information System (INIS)

    Hansen, L.F.

    1994-09-01

    The requirements to carry out accurate shielding calculations involved with the safe off-site transportation of packages containing nuclear warhead components, special assemblies and radioactive materials are discussed. The need for (a) detailed information on the geometry and material composition of the packaging and radioactive load, (b) accurate representation of the differential energy spectra (dN/dE) for the neutron and gamma spectra emitted by the radioactive materials enclosed in the packaging, (c) well-tested neutron and photon cross section libraries, (d) and accurate three-dimensional Monte Carlo transport codes are illustrated. A brief discussion of the need for reliable dose measurements is presented

  20. Legal protection against nuclear damage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1959-04-15

    The IAEA Director General appointed an international Panel of Experts to go into the question of Civil Liability and State Responsibility for Nuclear Hazards. The Panel had before it certain basic postulates formulated after a preliminary and tentative consideration of the subject. From the viewpoint of the public, the first postulate is, of course, that the use of nuclear energy be regulated by adequate licensing and control mechanisms so as to prevent any accidents. To the extent, however, that nuclear damage cannot be prevented, there must be liability on the part of the enterprise which caused the damage and, where damage exceeds its liability or its financial resources there should be some assurance of compensation by the State. This should be so not only within the borders of one State, but especially also on an international basis. Security should be required for the possible liability of the enterprises connected with a nuclear incident. Litigation with respect to liability should be concentrated in the most convenient tribunal and be governed by a single clearly defined law. The methods of distribution should meet general standards of equity and be as expeditious as possible. Emergency measures, especially evacuation, first aid and decontamination, should be organized and financed without delay. At the same time, the liability of an enterprise should not exceed its reasonable financial capabilities. This means that a ceiling should be imposed upon the amount of third party liability to which an enterprise could be held. And the liability should generally be such as can be covered by adequate financial security. Uniformity in the treatment of victims of nuclear incidents in all these fields is a desirable goal. Yet, if a rule adopted on an international level or suggested by uniform legislation were to be viable, it should adapt itself to the social, economic and legal order already existing in individual States. This may mean that in certain fields it

  1. Legal protection against nuclear damage

    International Nuclear Information System (INIS)

    1959-01-01

    The IAEA Director General appointed an international Panel of Experts to go into the question of Civil Liability and State Responsibility for Nuclear Hazards. The Panel had before it certain basic postulates formulated after a preliminary and tentative consideration of the subject. From the viewpoint of the public, the first postulate is, of course, that the use of nuclear energy be regulated by adequate licensing and control mechanisms so as to prevent any accidents. To the extent, however, that nuclear damage cannot be prevented, there must be liability on the part of the enterprise which caused the damage and, where damage exceeds its liability or its financial resources there should be some assurance of compensation by the State. This should be so not only within the borders of one State, but especially also on an international basis. Security should be required for the possible liability of the enterprises connected with a nuclear incident. Litigation with respect to liability should be concentrated in the most convenient tribunal and be governed by a single clearly defined law. The methods of distribution should meet general standards of equity and be as expeditious as possible. Emergency measures, especially evacuation, first aid and decontamination, should be organized and financed without delay. At the same time, the liability of an enterprise should not exceed its reasonable financial capabilities. This means that a ceiling should be imposed upon the amount of third party liability to which an enterprise could be held. And the liability should generally be such as can be covered by adequate financial security. Uniformity in the treatment of victims of nuclear incidents in all these fields is a desirable goal. Yet, if a rule adopted on an international level or suggested by uniform legislation were to be viable, it should adapt itself to the social, economic and legal order already existing in individual States. This may mean that in certain fields it

  2. Safeguarding and Protecting the Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    Bjornard, Trond; Garcia, Humberto; Desmond, William; Demuth, Scott

    2010-01-01

    International safeguards as applied by the International Atomic Energy Agency (IAEA) are a vital cornerstone of the global nuclear nonproliferation regime - they protect against the peaceful nuclear fuel cycle becoming the undetected vehicle for nuclear weapons proliferation by States. Likewise, domestic safeguards and nuclear security are essential to combating theft, sabotage, and nuclear terrorism by non-State actors. While current approaches to safeguarding and protecting the nuclear fuel cycle have been very successful, there is significant, active interest to further improve the efficiency and effectiveness of safeguards and security, particularly in light of the anticipated growth of nuclear energy and the increase in the global threat environment. This article will address two recent developments called Safeguards-by-Design and Security-by-Design, which are receiving increasing broad international attention and support. Expected benefits include facilities that are inherently more economical to effectively safeguard and protect. However, the technical measures of safeguards and security alone are not enough - they must continue to be broadly supported by dynamic and adaptive nonproliferation and security regimes. To this end, at the level of the global fuel cycle architecture, 'nonproliferation and security by design' remains a worthy objective that is also the subject of very active, international focus.

  3. ANS shielding standards for light-water reactors

    International Nuclear Information System (INIS)

    Trubey, D.K.

    1982-01-01

    The purpose of the American Nuclear Society Standards Subcommittee, ANS-6, Radiation Protection and Shielding, is to develop standards for radiation protection and shield design, to provide shielding information to other standards-writing groups, and to develop standard reference shielding data and test problems. A total of seven published ANS-6 standards are now current. Additional projects of the subcommittee, now composed of nine working groups, include: standard reference data for multigroup cross sections, gamma-ray absorption coefficients and buildup factors, additional benchwork problems for shielding problems and energy spectrum unfolding, power plant zoning design for normal and accident conditions, process radiation monitors, and design for postaccident radiological conditions

  4. Radiation protection of population under normal operation conditions of nuclear power plants

    International Nuclear Information System (INIS)

    Kunz, Eh.; Shvets, I.

    1976-01-01

    Evolution of shielding is defined in short; approaches suggested for applying in radiation protection or being used are evaluated and classified. Modern views analysis of a risk of biological irradiation consequences in public approaches to health protection in connection with the technical progress side by side with provision of separate persons protection requires attentin to the nuclear power plants protection optimization. Protection optimization suggests the analysis of separate components of technology and protection systems, used materials and constructive solutions, maintenance rules and operating load with respect to environmental discharge of radioactive products. It is expedient to carry out similtaneously the similar analysis with respect to the nuclear power plant personnel irradiation, as separate measures can affect both personnel and population irradiation [ru

  5. Radiological protection and nuclear safety postgraduate course

    International Nuclear Information System (INIS)

    Segado, R.C.; Menossi, C.A.

    1998-01-01

    Full text: The first Radiation Protection and Nuclear Safety Postgraduate Course was held in 1977, when the former Radioprotection and Nuclear Safety Branch of the National Atomic Energy Commission decided implement that course for the qualification of its professionals. After then, in 1980, by agreement between the CNEA, the National University of Buenos Aires and the Ministry of Health and Social Welfare got its present academic qualification as a Post-Graduate Course. Since then, it was sponsored by the IAEA. This Organization annually grants fellowships to fifteen students from different countries. Up to now, twenty consecutive courses have been delivered and more than five hundredth graduated, more than half of them coming from abroad. The aim of the course is the qualification and training in Radiological Protection and Nuclear Safety of those professionals involved in the design, construction, operation and decommissioning of Nuclear and Radioactive Installation and their related regulatory issues. (author) [es

  6. The protection system to Brazilian Nuclear Program

    International Nuclear Information System (INIS)

    Andreuzza, Mario Giussepp Santezzi Bertottelli

    1997-01-01

    The Sistema de Protecao ao Programa Nuclear Brasileiro-SIPRON (Protection System to Brazilian Nuclear Program) was established in 1980. It is intended to accomplish in only one system, all the actions related to security and protection for Nuclear Facilities in Brazil. The author presents in detail the protection system SIPRON, describing the system structure and organization, the functions and obligations of the system involved main organizations, as well as, the system operation and behaviour during an postulated occurrence of a nuclear emergency. It is also described an Exercise that happened in June of 1997 at the Nuclear Power Plant (NPP) Angra I, after two simulated tests in December of 1996 and April of 1997. The NPP Angra I Emergency Plan Exercise was a good opportunity to test the SIPRON structure and preparedness program. It was verified, included by International Atomic Energy Agency observers, the system involved organizations effectiveness and the procedures efficacy to protect the public and the environmental. Finally, it is shown the SIPRON activities of routine, the system obstacles and the expected future performances. (author)

  7. Nuclear Rocket Facility Decommissioning Project: Controlled Explosive Demolition of Neutron-Activated Shield Wall

    International Nuclear Information System (INIS)

    Michael R, Kruzic

    2008-01-01

    Located in Area 25 of the Nevada Test Site (NTS), the Test Cell A (TCA) Facility (Figure 1) was used in the early to mid-1960s for testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program, to further space travel. Nuclear rocket testing resulted in the activation of materials around the reactors and the release of fission products and fuel particles. The TCA facility, known as Corrective Action Unit 115, was decontaminated and decommissioned (D and D) from December 2004 to July 2005 using the Streamlined Approach for Environmental Restoration (SAFER) process, under the Federal Facility Agreement and Consent Order. The SAFER process allows environmental remediation and facility closure activities (i.e., decommissioning) to occur simultaneously, provided technical decisions are made by an experienced decision maker within the site conceptual site model. Facility closure involved a seven-step decommissioning strategy. First, preliminary investigation activities were performed, including review of process knowledge documentation, targeted facility radiological and hazardous material surveys, concrete core drilling and analysis, shield wall radiological characterization, and discrete sampling, which proved to be very useful and cost-effective in subsequent decommissioning planning and execution and worker safety. Second, site setup and mobilization of equipment and personnel were completed. Third, early removal of hazardous materials, including asbestos, lead, cadmium, and oil, was performed ensuring worker safety during more invasive demolition activities. Process piping was to be verified void of contents. Electrical systems were de-energized and other systems were rendered free of residual energy. Fourth, areas of high radiological contamination were decontaminated using multiple methods. Contamination levels varied across the facility. Fixed beta/gamma contamination levels ranged up to 2 million disintegrations per minute (dpm)/100

  8. Nuclear Rocket Facility Decommissioning Project: Controlled Explosive Demolition of Neutron-Activated Shield Wall

    Energy Technology Data Exchange (ETDEWEB)

    Michael R. Kruzic

    2008-06-01

    Located in Area 25 of the Nevada Test Site (NTS), the Test Cell A (TCA) Facility (Figure 1) was used in the early to mid-1960s for testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program, to further space travel. Nuclear rocket testing resulted in the activation of materials around the reactors and the release of fission products and fuel particles. The TCA facility, known as Corrective Action Unit 115, was decontaminated and decommissioned (D&D) from December 2004 to July 2005 using the Streamlined Approach for Environmental Restoration (SAFER) process, under the Federal Facility Agreement and Consent Order. The SAFER process allows environmental remediation and facility closure activities (i.e., decommissioning) to occur simultaneously, provided technical decisions are made by an experienced decision maker within the site conceptual site model. Facility closure involved a seven-step decommissioning strategy. First, preliminary investigation activities were performed, including review of process knowledge documentation, targeted facility radiological and hazardous material surveys, concrete core drilling and analysis, shield wall radiological characterization, and discrete sampling, which proved to be very useful and cost-effective in subsequent decommissioning planning and execution and worker safety. Second, site setup and mobilization of equipment and personnel were completed. Third, early removal of hazardous materials, including asbestos, lead, cadmium, and oil, was performed ensuring worker safety during more invasive demolition activities. Process piping was to be verified void of contents. Electrical systems were de-energized and other systems were rendered free of residual energy. Fourth, areas of high radiological contamination were decontaminated using multiple methods. Contamination levels varied across the facility. Fixed beta/gamma contamination levels ranged up to 2 million disintegrations per minute (dpm)/100

  9. Shielding analysis in the design phase of the new Emergency Operation Facility for Tihange Nuclear Power Plant

    Science.gov (United States)

    Genard, Gilles; Portal, Romain; Bouchat, Virginie; Vanderperre, Serge

    2017-09-01

    In the framework of the design studies for a new Emergency Operation Facility (EOF) for Tihange NPP, radiation protection analyses are needed to comply with effective dose rate criteria. In this aim, the shielding performed by, at the one hand, external walls and roof of the building and, on the other hand, internal walls, has been sized by means of MicroShield calculations. This paper explains how the calculations for external walls, doors, roof, floor and internal walls are made. The assumptions on the source terms and on the source geometry as well as the way the shielding is determined and the results of the sizing are presented.

  10. Shielding analysis in the design phase of the new Emergency Operation Facility for Tihange Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    Genard Gilles

    2017-01-01

    Full Text Available In the framework of the design studies for a new Emergency Operation Facility (EOF for Tihange NPP, radiation protection analyses are needed to comply with effective dose rate criteria. In this aim, the shielding performed by, at the one hand, external walls and roof of the building and, on the other hand, internal walls, has been sized by means of MicroShield calculations. This paper explains how the calculations for external walls, doors, roof, floor and internal walls are made. The assumptions on the source terms and on the source geometry as well as the way the shielding is determined and the results of the sizing are presented.

  11. Protection of the patient in nuclear medicine

    International Nuclear Information System (INIS)

    1987-01-01

    In ICRP Publication 52, the 'Protection of the Patient in Nuclear Medicine', is concerned with exposures of patients resulting from the administration of radiopharmaceuticals for diagnostic, therapeutic and research purposes. The report includes guidelines for nuclear medicine physicians, radiologists, medical physicists and technologists on the factors that influence absorbed doses to patients from different types of nuclear medicine examinations. Other topics in the report include education and training, estimates of absorbed dose, design of facilities, instrumentation, quality assurance and control and preparation, quality assurance and control of radiopharmaceuticals. (U.K.)

  12. Modifier cation effects on (29)Si nuclear shielding anisotropies in silicate glasses.

    Science.gov (United States)

    Baltisberger, Jay H; Florian, Pierre; Keeler, Eric G; Phyo, Pyae A; Sanders, Kevin J; Grandinetti, Philip J

    2016-07-01

    We have examined variations in the (29)Si nuclear shielding tensor parameters of SiO4 tetrahedra in a series of seven alkali and alkaline earth silicate glass compositions, Cs2O·4.81 SiO2, Rb2O·3.96 SiO2, Rb2O·2.25 SiO2, K2O·4.48 SiO2, Na2O·4.74 SiO2, BaO·2.64 SiO2, and SrO·2.36 SiO2, using natural abundance (29)Si two-dimensional magic-angle flipping (MAF) experiments. Our analyses of these 2D spectra reveal a linear dependence of the (29)Si nuclear shielding anisotropy of Q((3)) sites on the Si-non-bridging oxygen bond length, which in turn depends on the cation potential and coordination of modifier cations to the non-bridging oxygen. We also demonstrate how a combination of Cu(2+) as a paramagnetic dopant combined with echo train acquisition can reduce the total experiment time of (29)Si 2D NMR measurements by two orders of magnitude, enabling higher throughput 2D NMR studies of glass structure. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Modifier cation effects on 29Si nuclear shielding anisotropies in silicate glasses

    Science.gov (United States)

    Baltisberger, Jay H.; Florian, Pierre; Keeler, Eric G.; Phyo, Pyae A.; Sanders, Kevin J.; Grandinetti, Philip J.

    2016-07-01

    We have examined variations in the 29Si nuclear shielding tensor parameters of SiO4 tetrahedra in a series of seven alkali and alkaline earth silicate glass compositions, Cs2O · 4.81 SiO2, Rb2O · 3.96 SiO2, Rb2O · 2.25 SiO2, K2O · 4.48 SiO2, Na2O · 4.74 SiO2, BaO · 2.64 SiO2, and SrO · 2.36 SiO2, using natural abundance 29Si two-dimensional magic-angle flipping (MAF) experiments. Our analyses of these 2D spectra reveal a linear dependence of the 29Si nuclear shielding anisotropy of Q(3) sites on the Si-non-bridging oxygen bond length, which in turn depends on the cation potential and coordination of modifier cations to the non-bridging oxygen. We also demonstrate how a combination of Cu2+ as a paramagnetic dopant combined with echo train acquisition can reduce the total experiment time of 29Si 2D NMR measurements by two orders of magnitude, enabling higher throughput 2D NMR studies of glass structure.

  14. Shielding analysis in the design phase of the new Emergency Operation Facility for Tihange Nuclear Power Plant

    OpenAIRE

    Genard Gilles; Portal Romain; Bouchat Virginie; Vanderperre Serge

    2017-01-01

    In the framework of the design studies for a new Emergency Operation Facility (EOF) for Tihange NPP, radiation protection analyses are needed to comply with effective dose rate criteria. In this aim, the shielding performed by, at the one hand, external walls and roof of the building and, on the other hand, internal walls, has been sized by means of MicroShield calculations. This paper explains how the calculations for external walls, doors, roof, floor and internal walls are made. The assump...

  15. Radiation shielding application of lead glass

    International Nuclear Information System (INIS)

    Nathuram, R.

    2017-01-01

    Nuclear medicine and radiotherapy centers equipped with high intensity X-ray or teletherapy sources use lead glasses as viewing windows to protect personal from radiation exposure. Lead is the main component of glass which is responsible for shielding against photons. It is therefore essential to check the shielding efficiency before they are put in use. This can be done by studying photon transmission through the lead glasses. The study of photon transmission in shielding materials has been an important subject in medical physics and is potential useful in the development of radiation shielding materials

  16. The physical protection of nuclear material and nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-01

    The latest review (1993) of this document was of limited scope and resulted in changes to the text of INFCIRC/225/Rev.2 designed to make the categorization table in that document consistent with the categorization table contained in the Convention on Physical Protection of Nuclear Materials. Consequently, a comprehensive review of INFCIRC/225 has not been conducted since 1989. Consequently, a meeting of national experts was convened from 2-5 June 1998 and from 27-29 October 1998 for a thorough review of INFCIRC/225/Rev.3. The revised document reflects the recommendations of the national experts to improve the structure and clarity of the document and to take account of improved technology and current international and national practices. In particular, a chapter has been added which provides specific recommendations related to sabotage of nuclear facilities and nuclear material. As a result of this addition, the title has been changed to 'The Physical Protection of Nuclear Material and Nuclear Facilities'. The recommendations presented in this IAEA document reflect a broad consensus among Member States on the requirements which should be met by systems for the physical protection of nuclear materials and facilities. It is hoped that they will provide helpful guidance for Member States.

  17. The physical protection of nuclear material and nuclear facilities

    International Nuclear Information System (INIS)

    1999-06-01

    The latest review (1993) of this document was of limited scope and resulted in changes to the text of INFCIRC/225/Rev.2 designed to make the categorization table in that document consistent with the categorization table contained in the Convention on Physical Protection of Nuclear Materials. Consequently, a comprehensive review of INFCIRC/225 has not been conducted since 1989. Consequently, a meeting of national experts was convened from 2-5 June 1998 and from 27-29 October 1998 for a thorough review of INFCIRC/225/Rev.3. The revised document reflects the recommendations of the national experts to improve the structure and clarity of the document and to take account of improved technology and current international and national practices. In particular, a chapter has been added which provides specific recommendations related to sabotage of nuclear facilities and nuclear material. As a result of this addition, the title has been changed to 'The Physical Protection of Nuclear Material and Nuclear Facilities'. The recommendations presented in this IAEA document reflect a broad consensus among Member States on the requirements which should be met by systems for the physical protection of nuclear materials and facilities. It is hoped that they will provide helpful guidance for Member States

  18. Device for protecting the containment vessel dome of a nuclear reactor

    International Nuclear Information System (INIS)

    Allain, A.; Filloleau, E.; Mulot, P.

    1976-01-01

    A device is disclosed for protecting the dome of a nuclear reactor containment vessel against the upward displacement of the concrete shield slab of said reactor and the resultant effects of tilting of an equipment unit mounted on the shield slab at the periphery of said slab, wherein said device comprises: (1) means for separating the equipment unit into two sections consisting of an upper section and a lower section, said lower section being rigidly fixed to said shield slab and said means being actuated by the upward displacement of said slab, (2) a system for vertical rectilinear guiding of said upper section within the containment vessel, and (3) rigid mechanical components which provide a coupling between the aforesaid upper and lower sections of the equipment unit and exert on said upper section under the action of the tilting motion of said lower section a thrust which causes the upward displacement of said upper section

  19. Fire protection guidelines for nuclear power plants

    International Nuclear Information System (INIS)

    1976-06-01

    Guidelines acceptable to the NRC staff for implementing in the development of a fire protection program for nuclear power plants. The purpose of the fire protection program is to ensure the capability to shut down the reactor and maintain it in a safe shutdown condition and to minimize radioactive releases to the environment in the event of a fire. If designs or methods different from the guidelines presented herein are used, they must provide fire protection comparable to that recommended in the guidelines. Suitable bases and justification should be provided for alternative approaches to establish acceptable implementaion of General Design Criterion 3

  20. Shielding of Medical Radiation Facilities - National Council on Radiation Protection and Measurements Reports No. 147 and No. 151

    International Nuclear Information System (INIS)

    KASE, K.R.

    2008-01-01

    The National Council on Radiation Protection and Measurements of the United States (NCRP) has issued two reports in the past 18 months that provide methods and data for designing shielding for diagnostic radiological imaging and radiation therapy facilities. These reports update previous publications on this subject with revised methods that take into account new technologies, results from measurements and new data that have been published in the last 30 years. This paper gives a brief summary of the contents of these reports, the methods recommended for determining the shielding required and the data provided to aid in the calculations

  1. Benchmark shielding calculations for the NEACRP [Nuclear Energy Agency-Committee on Reactor Physics] Working Group on shielding assessment of transportation packages

    International Nuclear Information System (INIS)

    Broadhead, B.L.; Brady, M.C.; Parks, C.V.

    1990-11-01

    In 1985, the Nuclear Energy Agency-Committee on Reactor Physics (NEACRP) established a working group on shielding assessment of transportation packages. Following the initial distribution of a set of six problems, discussions were held at the Organization for Economic Cooperation and Development (OECD) Headquarters in Paris, France, in June/July 1986, May 1988, and February/March 1990. The US contribution to the working group is documented in this report. The results from this effort permit the evaluation of a number of approximations and effects that must be considered in a typical shielding analysis of a transportation cask. Among the effects reported here are the performance of multiple cross-section sets, the comparison of several source generation codes, and multidimensional versus one-dimensional (1-D) analyses. 18 refs., 16 figs., 33 tabs

  2. Fire protection in nuclear power plants

    International Nuclear Information System (INIS)

    1992-01-01

    The Code on Design (Safety Series 50-C-D (Rev. 1)) within the NUSS (Nuclear Safety Standards) programme of the IAEA points out the necessity of measures for protecting plant items which are important to safety against fires of internal and external origin. Experience of the past two decades in the operation of nuclear power plants and modern analysis techniques confirm that fire may be a real threat to nuclear safety and should receive adequate attention from the beginning of the design process throughout the life of the plant. Within the framework of the NUSS programme, a Safety Guide on fire protection had therefore been developed to enlarge on the general requirements given in the Code. Since its first publication in 1979, there has been considerable development in protection technology and analysis methods and after the Chernobyl accident it was decided to revise the existing Guide. The present Safety Guide is intended to advise designers, safety assessors and regulators on the concept of fire protection in the design of nuclear power plants and on recommended ways of implementing the concept in some detail in practice. Figs, 1 tab

  3. Radiation Protection, Nuclear Safety and Security

    International Nuclear Information System (INIS)

    Faye, Ndeye Arame Boye; Ndao, Ababacar Sadikhe; Tall, Moustapha Sadibou

    2014-01-01

    Senegal has put in place a regulatory framework which allows to frame legally the use of radioactive sources. A regulatory authority has been established to ensure its application. It is in the process of carrying out its regulatory functions. It cooperates with appropriate national or international institutions operating in fields related to radiation protection, safety and nuclear safety.

  4. Radiological protection and nuclear power plants

    International Nuclear Information System (INIS)

    Delpla, M.

    Dosimetric results obtained inside and outside nuclear power plants are examined with a review to proposing revision of the radiological protection standards. Dose limits are considered with regard to leukemia and genetic effects. Other topics discussed are: observed collective damage and mean risk; lethal exposure; healing and sign change of additional risk; and genetic effects of radiation on mice

  5. Agriculture protected against nuclear power hazards

    International Nuclear Information System (INIS)

    Warner, J.

    1982-01-01

    Near the Koeberg-1 reactor agriculture is being protected against nuclear power hazards. Radioactivity is frequently tested in e.g. milk and soils. This article discusses the tests and the measurements of radioactivity in the vicinity of the Koeberg-1 reactor

  6. Multi-objective optimization of a compact pressurized water nuclear reactor computational model for biological shielding design using innovative materials

    Energy Technology Data Exchange (ETDEWEB)

    Tunes, M.A., E-mail: matheus.tunes@usp.br [Department of Metallurgical and Materials Engineering, Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes, 2463 – CEP 05508 – 030 São Paulo (Brazil); Oliveira, C.R.E. de, E-mail: cassiano@unm.edu [Department of Nuclear Engineering, The University of New Mexico, Farris Engineering Center, 221, Albuquerque, NM 87131-1070 (United States); Schön, C.G., E-mail: schoen@usp.br [Department of Metallurgical and Materials Engineering, Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes, 2463 – CEP 05508 – 030 São Paulo (Brazil)

    2017-03-15

    Highlights: • Use of two n-γ transport codes leads to optimized model of compact nuclear reactor. • It was possible to safely reduce both weight and volume of the biological shielding. • Best configuration obtained by using new composites for both γ and n attenuation. - Abstract: The aim of the present work is to develop a computational model of a compact pressurized water nuclear reactor (PWR) to investigate the use of innovative materials to enhance the biological shielding effectiveness. Two radiation transport codes were used: the first one – MCNP – for the PWR design and the GEM/EVENT to simulate (in a 1D slab) the behavior of several materials and shielding thickness on gamma and neutron radiation. Additionally MATLAB Optimization Toolbox was used to provide new geometric configurations of the slab aiming at reducing the volume and weight of the walls by means of a cost/objective function. It is demonstrated in the reactor model that the dose rate outside biological shielding has been reduced by one order of magnitude for the optimized model compared with the initial configuration. Volume and weight of the shielding walls were also reduced. The results indicated that one-dimensional deterministic code to reach an optimized geometry and test materials, combined with a three-dimensional model of a compact nuclear reactor in a stochastic code, is a fast and efficient procedure to test shielding performance and optimization before the experimental assessment. A major outcome of this research is that composite materials (ECOMASS 2150TU96) may replace (with advantages) traditional shielding materials without jeopardizing the nuclear power plant safety assurance.

  7. Surface protection in bio-shields via a functional soft skin layer: Lessons from the turtle shell.

    Science.gov (United States)

    Shelef, Yaniv; Bar-On, Benny

    2017-09-01

    The turtle shell is a functional bio-shielding element, which has evolved naturally to provide protection against predator attacks that involve biting and clawing. The near-surface architecture of the turtle shell includes a soft bi-layer skin coating - rather than a hard exterior - which functions as a first line of defense against surface damage. This architecture represents a novel type of bio-shielding configuration, namely, an inverse structural-mechanical design, rather than the hard-coated bio-shielding elements identified so far. In the current study, we used experimentally based structural modeling and FE simulations to analyze the mechanical significance of this unconventional protection architecture in terms of resistance to surface damage upon extensive indentations. We found that the functional bi-layer skin of the turtle shell, which provides graded (soft-softer-hard) mechanical characteristics to the bio-shield exterior, serves as a bumper-buffer mechanism. This material-level adaptation protects the inner core from the highly localized indentation loads via stress delocalization and extensive near-surface plasticity. The newly revealed functional bi-layer coating architecture can potentially be adapted, using synthetic materials, to considerably enhance the surface load-bearing capabilities of various engineering configurations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Interface between radiation protection and nuclear safety

    International Nuclear Information System (INIS)

    Bengtsson, G.; Hoegberg, L.

    1991-01-01

    Interface issues concern the character and management of overlaps between radiation protection and nuclear safety in nuclear power plants. Typical examples include the selection of inspection and maintenance volumes in order to balance occupational radiation doses versus the safety status of the plant, and the intentional release to the environment in the course of an accident in order to secure better plant control. The paper discusses whether it is desirable and possible to employ a consistent management of interface issues with trade-offs between nuclear safety and radiation protection. Illustrative examples are quoted from a major Nordic research programme on risk analysis and safety rationale. These concern for instance in-service inspections, modifications of plant systems and constructions after the plant has been taken into operation, and studies on the limitations of probabilistic safety assessment. They indicate that in general there are no simple rules for such trade-offs

  9. Ecological radiation protection criteria for nuclear power

    International Nuclear Information System (INIS)

    Kryshev, I.I.

    1993-01-01

    By now a large quantity of radioactive hazards of all sizes and shapes has accumulated in Russia. They include RBMK, VVER, and BN (fast-neutron) nuclear power plants, nuclear fuel processing plants, radioactive waste dumps, ships with nuclear power units, etc. In order to evaluate the radioecological situation correctly, the characteristics of the radioactive contamination must be compiled in these areas with some system of criteria which will provide an acceptable level of ecological safety. Currently health criteria for radiation protection are, which are oriented to man's radiation protection, predominate. Here the concept of a thresholdless linear dose-response dependence, which has been confirmed experimentally only at rather high doses (above 1 Gy), is taken as the theoretical basis for evaluating and normalizing radiation effects. According to one opinion, protecting people against radiation is sufficient to protect other types of organisms, although they are not necessarily of the same species. However, from the viewpoint of ecology, this approach is incorrect, because it does not consider radiation dose differences between man and other living organisms. The article discusses dose-response dependences for various organisms, biological effects of ionizing radiation, and appropriate radiation protection criteria

  10. Health and nuclear: For which radiological protection?

    International Nuclear Information System (INIS)

    Proust, Claude

    2016-01-01

    The author aims at providing citizen with knowledge in the field of health in relationship with nuclear energy. A first part proposes a historical overview of knowledge of nuclear effects on health, with references to the discovery and first works on radioactivity, to the Manhattan project, to the creation of national and international bodies in charge of nuclear issues, to various nuclear accidents and their consequences. In the second part, the author describes mechanisms of radiation protection and its organisation at the world level (ICRP, UNSCEAR, IAEA, and so on), and discusses in a very critical way the basic aspects which are now governing radiation protection standards. Indeed, he outlines denials, lies, and the inappropriate character of the risk model created in 1951. He also discusses the optimisation principle, criticises the application of deterministic effect criteria to stochastic effects. In the fourth part, the author analyses consequences of the present official radiation protection which he considers as a pseudo-science as shown by misleading assessments of Chernobyl victims, and by publications which also criticise this science. The last part addresses the specific case of France

  11. Advanced BorobondTM Shields for Nuclear Materials Containment and BorobondTM Immobilization of Volatile Fission Products - Final CRADA Report

    International Nuclear Information System (INIS)

    Wagh, Arun S.

    2016-01-01

    Borobond is a company-proprietary material developed by the CRADA partner in collaboration with Argonne, and is based on Argonne's Ceramicrete technology. It is being used by DOE for nuclear materials safe storage, and Boron Products, LLC is the manufacturer and supplier of Borobond. The major objective of this project was to produce a more versatile composition of this material and find new applications. Major target applications were use for nuclear radiation shields, such as in dry storage casks; use in immobilization of most difficult waste streams, such as Hanford K-Basin waste; use for soluble and volatile fission products, such as Cs, Tc, Sr, and I; and use for corrosion and fire protection applications in nuclear facilities.

  12. Improvement of the shield ability and lightweight of a radiation protective apron

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Keun; Jang, Young Il [Kwangju Health College, Kwang-ju (Korea, Republic of); Kim, Jung Min [Junior College of Health Sciences, Korea University, Seoul (Korea, Republic of)

    2003-06-15

    In this work, we characterized the shield ability and lightweight of radiation protective aprons which were consisted of various metal (Pb, Sn, Ni, Ti and Cu) by measuring the x-ray dose transmitted through the filters. The transmitted ratio and lead equivalent of various metal were obtained by linear interpolation and the lead equivalent of double layered filters contained Pb layer was determined. The transmitted ratio of the apron (0.25 mmPb) specified in KS B 0845 was 5.2%. The transmitted ratio of the filters at the thickness of 0.6 mm was decreased in the order of Ni (32.60%), Ti (17.75%), Cu (13.25%) and Sn (3.84%). From the results of experimental evaluation for combined filter of Pb and Sn, it was founded that in the case of the first Sn layer, the lead equivalent was higher than that of the first Pb layer. The lead equivalent corresponding to apron of 0.25 mmPb was obtained in the double layered filters of Sn (0.19 mm)-Pb (0.1 mm) and Pb (0.1 mm)-Sn (0.37 mm). Thus, the Sn-Pb filter had the lower weight about 13% than apron of 0.25 mmPb.

  13. Radiation protection of staff in 111In radionuclide therapy--is the lead apron shielding effective?

    Science.gov (United States)

    Lyra, M; Charalambatou, P; Sotiropoulos, M; Diamantopoulos, S

    2011-09-01

    (111)In (Eγ = 171-245 keV, t1/2 = 2.83 d) is used for targeted therapies of endocrine tumours. An average activity of 6.3 GBq is injected into the liver by catheterisation of the hepatic artery. This procedure is time-consuming (4-5 min) and as a result, both the physicians and the technical staff involved are subjected to radiation exposure. In this research, the efficiency of the use of lead apron has been studied as far as the radiation protection of the working staff is concerned. A solution of (111)In in a cylindrical scattering phantom was used as a source. Close to the scattering phantom, an anthropomorphic male Alderson RANDO phantom was positioned. Thermoluminescent dosemeters were located in triplets on the front surface, in the exit and in various depths in the 26th slice of the RANDO phantom. The experiment was repeated by covering the RANDO phantom by a lead apron 0.25 mm Pb equivalent. The unshielded dose rates and the shielded photon dose rates were measured. Calculations of dose rates by Monte Carlo N-particle transport code were compared with this study's measurements. A significant reduction of 65 % on surface dose was observed when using lead apron. A decrease of 30 % in the mean absorbed dose among the different depths of the 26th slice of the RANDO phantom has also been noticed. An accurate correlation of the experimental results with Monte Carlo simulation has been achieved.

  14. Improvement of the shield ability and lightweight of a radiation protective apron

    International Nuclear Information System (INIS)

    Kim, Young Keun; Jang, Young Il; Kim, Jung Min

    2003-01-01

    In this work, we characterized the shield ability and lightweight of radiation protective aprons which were consisted of various metal (Pb, Sn, Ni, Ti and Cu) by measuring the x-ray dose transmitted through the filters. The transmitted ratio and lead equivalent of various metal were obtained by linear interpolation and the lead equivalent of double layered filters contained Pb layer was determined. The transmitted ratio of the apron (0.25 mmPb) specified in KS B 0845 was 5.2%. The transmitted ratio of the filters at the thickness of 0.6 mm was decreased in the order of Ni (32.60%), Ti (17.75%), Cu (13.25%) and Sn (3.84%). From the results of experimental evaluation for combined filter of Pb and Sn, it was founded that in the case of the first Sn layer, the lead equivalent was higher than that of the first Pb layer. The lead equivalent corresponding to apron of 0.25 mmPb was obtained in the double layered filters of Sn (0.19 mm)-Pb (0.1 mm) and Pb (0.1 mm)-Sn (0.37 mm). Thus, the Sn-Pb filter had the lower weight about 13% than apron of 0.25 mmPb

  15. Radiation protection of staff in 111In radionuclide therapy-Is the lead apron shielding effective?

    International Nuclear Information System (INIS)

    Lyra, M.; Charalambatou, P.; Sotiropoulos, M.; Diamantopoulos, S.

    2011-01-01

    111 In (Eγ=171-245 keV, t1/2=2.83 d) is used for targeted therapies of endocrine tumours. An average activity of 6.3 GBq is injected into the liver by catheterisation of the hepatic artery. This procedure is time-consuming (4-5 min) and as a result, both the physicians and the technical staff involved are subjected to radiation exposure. In this research, the efficiency of the use of lead apron has been studied as far as the radiation protection of the working staff is concerned. A solution of 111 In in a cylindrical scattering phantom was used as a source. Close to the scattering phantom, an anthropomorphic male Alderson RANDO phantom was positioned. Thermoluminescent dosemeters were located in triplets on the front surface, in the exit and in various depths in the 26. slice of the RANDO phantom. The experiment was repeated by covering the RANDO phantom by a lead apron 0.25 mm Pb equivalent. The unshielded dose rates and the shielded photon dose rates were measured. Calculations of dose rates by Monte Carlo N-particle transport code were compared with this study's measurements. A significant reduction of 65 % on surface dose was observed when using lead apron. A decrease of 30 % in the mean absorbed dose among the different depths of the 26. slice of the RANDO phantom has also been noticed. An accurate correlation of the experimental results with Monte Carlo simulation has been achieved. (authors)

  16. Heavy density concrete for nuclear radiation shielding and power stations: [Part]3

    International Nuclear Information System (INIS)

    Singha Roy, P.K.

    1987-01-01

    This article is the third part of the paper entitled 'Heavy density concrete for nuclear radiation shielding and power stations'. Specific considerations relevant to natural but manufactured heavy aggregates like haematite used in India are briefly discussed. They include water-cement ratio, strength versus water-cement ratio, mix design strength and aggregate grading. Some typical mix proportions in haematite concretes used in India are given. Equipment for heavy density concrete is mentioned. Quality control methods and tests for heavy density concrete are described under the heading: type and chemical composition of the rock, specific gravity and surface absorption of the aggregates, grading of aggregates, cement, batching, mixing, compressive strength, and density. Construction aspects such as form work, placement, vibration, finishing, and temperature control are discussed. Finally it is pointed out that for optimising the design and economy of heavy density concrete, it is necessary to carry out country-wide survey of suitable materials, to study their properties, suitability and effectiveness in shielding radiation. (M.G.B.)

  17. Characterization of the Shielded Neutron Source at Triangle Universities Nuclear Laboratory

    Science.gov (United States)

    Hobson, Chad; Finch, Sean; Howell, Calvin; Malone, Ron; Tornow, Wernew

    2016-09-01

    In 2015, Triangle Universities Nuclear Laboratory rebuilt its shielded neutron source (SNS) with the goal of improving neutron beam collimation and reducing neutron and gamma-ray backgrounds. Neutrons are produced via the 2H(d,n)3He reaction and then collimated by heavy shielding to form a beam. The SNS has the ability to produce both a rectangular and circular neutron beam through use of two collimators with different beam apertures. Our work characterized both the neutron beam profiles as well as the neutron and gamma-ray backgrounds at various locations around the SNS. This characterization was performed to provide researchers who use the SNS with beam parameters necessary to plan and conduct an experiment. Vertical and horizontal beam profiles were measured at two different distances from the neutron production cell by scanning a small plastic scintillator across the face of the beam at various energies for each collimator. Background neutron and gamma-ray intensities were measured using time-of-flight techniques at 10 MeV and 16 MeV with the rectangular collimator. We present results on the position and size of neutron beam as well as on the structure and magnitude of the backgrounds.

  18. Oscillatory vapour shielding of liquid metal walls in nuclear fusion devices.

    Science.gov (United States)

    van Eden, G G; Kvon, V; van de Sanden, M C M; Morgan, T W

    2017-08-04

    Providing an efficacious plasma facing surface between the extreme plasma heat exhaust and the structural materials of nuclear fusion devices is a major challenge on the road to electricity production by fusion power plants. The performance of solid plasma facing surfaces may become critically reduced over time due to progressing damage accumulation. Liquid metals, however, are now gaining interest in solving the challenge of extreme heat flux hitting the reactor walls. A key advantage of liquid metals is the use of vapour shielding to reduce the plasma exhaust. Here we demonstrate that this phenomenon is oscillatory by nature. The dynamics of a Sn vapour cloud are investigated by exposing liquid Sn targets to H and He plasmas at heat fluxes greater than 5 MW m -2 . The observations indicate the presence of a dynamic equilibrium between the plasma and liquid target ruled by recombinatory processes in the plasma, leading to an approximately stable surface temperature.Vapour shielding is one of the interesting mechanisms for reducing the heat load to plasma facing components in fusion reactors. Here the authors report on the observation of a dynamic equilibrium between the plasma and the divertor liquid Sn surface leading to an overall stable surface temperature.

  19. Design experience: CRBRP radiation shielding

    International Nuclear Information System (INIS)

    Disney, R.K.; Chan, T.C.; Gallo, F.G.; Hedgecock, L.R.; McGinnis, C.A.; Wrights, G.N.

    1978-11-01

    The Clinch River Breeder Reactor Plant (CRBRP) is being designed as a fast breeder demonstration project in the U.S. Liquid Metal Fast Breeder Reactor (LMFBR) program. Radiation shielding design of the facility consists of a comprehensive design approach to assure compliance with design and government regulatory requirements. Studies conducted during the CRBRP design process involved the aspects of radiation shielding dealing with protection of components, systems, and personnel from radiation exposure. Achievement of feasible designs, while considering the mechanical, structural, nuclear, and thermal performance of the component or system, has required judicious trade-offs in radiation shielding performance. Specific design problems which have been addressed are in-vessel radial shielding to protect permanent core support structures, flux monitor system shielding to isolate flux monitoring systems for extraneous background sources, reactor vessel support shielding to allow personnel access to the closure head during full power operation, and primary heat transport system pipe chaseway shielding to limit intermediate heat transport system sodium system coolant activation. The shielding design solutions to these problems defined a need for prototypic or benchmark experiments to provide assurance of the predicted shielding performance of selected design solutions and the verification of design methodology. Design activities of CRBRP plant components an systems, which have the potential for radiation exposure of plant personnel during operation or maintenance, are controlled by a design review process related to radiation shielding. The program implements design objectives, design requirements, and cost/benefit guidelines to assure that radiation exposures will be ''as low as reasonably achievable''

  20. A model-based approach of scatter dose contributions and efficiency of apron shielding for radiation protection in CT.

    Science.gov (United States)

    Weber, N; Monnin, P; Elandoy, C; Ding, S

    2015-12-01

    Given the contribution of scattered radiations to patient dose in CT, apron shielding is often used for radiation protection. In this study the efficiency of apron was assessed with a model-based approach of the contributions of the four scatter sources in CT, i.e. external scattered radiations from the tube and table, internal scatter from the patient and backscatter from the shielding. For this purpose, CTDI phantoms filled with thermoluminescent dosimeters were scanned without apron, and then with an apron at 0, 2.5 and 5 cm from the primary field. Scatter from the tube was measured separately in air. The scatter contributions were separated and mathematically modelled. The protective efficiency of the apron was low, only 1.5% in scatter dose reduction on average. The apron at 0 cm from the beam lowered the dose by 7.5% at the phantom bottom but increased the dose by 2% at the top (backscatter) and did not affect the centre. When the apron was placed at 2.5 or 5 cm, the results were intermediate to the one obtained with the shielding at 0 cm and without shielding. The apron effectiveness is finally limited to the small fraction of external scattered radiation. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  1. The nuclear energy for the environment protection

    International Nuclear Information System (INIS)

    Souza, Jair A.M. de.

    1992-01-01

    The environmental question is currently the greater preoccupation all the world, particularly, the atmospheric pollution, generating the acid rains and the heater effect. The transportation, residential, agricultural, industrial and electric sectors contribute for the atmospheric pollution. In this work, the author analyzes important actions in Europe and United States of America in order to reduce this pollution. The paper intends to demystifies that the nuclear energy would be harmful to the environment, demonstrating exactly the contrary - due to the emission cares and controls coming from the nuclear power plants, this source of electric energy generation constitutes is an important factor of environment protection

  2. Ring thermal shield piping modification at Pickering Nuclear Generating Station 'A' Unit 1

    International Nuclear Information System (INIS)

    Brown, R.; Cobanoglu, M.M.

    1995-01-01

    Each of the four Pickering Nuclear Generating Station A (PNGSA) CANDU units was constructed with its reactor and dump tank surrounded by a concrete Calandria Vault (CV). The Ring Thermal Shield (RTS) system at PNGSA units is a water cooled structure with internal cooling channels with the purpose of attenuating excessive heat flux from the calandria shell to the end shield rings and adjoining concrete (Figure 1). In newer CANDU units the reactor calandria vessel is surrounded by a large water filled shield tank which eliminates the requirement for the RTS system. The RTS structures are situated in the space between the calandria and the vault walls. Each RTS is assembled from eight flat sided carbon steel segments, tilted towards the calandria and supported from the end shield rings. Cooling water to the RTS is supplied by carbon steel cooling pipes with a portion of the pipe run embedded in the vault walls. Flow through each RTS is divided into two independent circuits, having an inlet and an outlet cooling line. There are four locations of RTS inlet and outlet cooling lines. The inlet lines are located at the bottom and the outlet lines at the top of the RTS. The 'L' shaped section of RTS inlet and outlet cooling lines, from the RTS waterbox to the start of embedded portion at the concrete wall, had become defective due to corrosion induced by excessive Moisture levels in the calandria vaults. An on-line leak sealing capability was developed and placed in service in all four PNGSA units. However, a leak found during the 1994 Unit 1 outage was too large,to seal with the current capability, forcing Ontario Hydro (OH) to develop a method to replace the corroded pipes. The repair project was subject to some lofty performance targets. All tools had to be able to withstand dose rates of up to 3000 Rem/hour. These tools, along with procedures and personnel had to successfully repair the RTS system within 6 months otherwise a costly outage extension would result. This

  3. Shielding benchmark problems

    International Nuclear Information System (INIS)

    Tanaka, Shun-ichi; Sasamoto, Nobuo; Oka, Yoshiaki; Kawai, Masayoshi; Nakazawa, Masaharu.

    1978-09-01

    Shielding benchmark problems were prepared by the Working Group of Assessment of Shielding Experiments in the Research Comittee on Shielding Design of the Atomic Energy Society of Japan, and compiled by the Shielding Laboratory of Japan Atomic Energy Research Institute. Twenty-one kinds of shielding benchmark problems are presented for evaluating the calculational algorithm and the accuracy of computer codes based on the discrete ordinates method and the Monte Carlo method and for evaluating the nuclear data used in the codes. (author)

  4. Physical protection nuclear facilities against sabotage

    International Nuclear Information System (INIS)

    Hagemann, A.

    2001-01-01

    Full text: INFCIRC 225 Rev. 4 has introduced the Design Basis Threat, DBT, as a key element of the states physical protection system. The DBT is a definition which determines the level of physical protection of nuclear material during use, storage, transport and of nuclear facilities. It the basis for physical protection concepts and for the design of measures the operator or licensee has to provide. By this means it is also a definition of the responsibility for the physical protection which the operator accepts with the license. The new chapter designated to the physical protection against sabotage which has resulted also in the amendment of the title in INFCIRC 225 demonstrates the grown international concern about the potential consequences of sabotage. More than the physical protection against unauthorized removal the physical protection against sabotage has interfaces with the nuclear safety field. The basis of protection against sabotage therefore is much more based on the facility design-the safety design of the facility. Using the DBT the competent authority is in the position to determine the level of protection against sabotage and the remaining risk which has to be accepted. This risk of course depends on the real threat which is not known in advance. The acceptance of the remaining risk depends on both the assessment of the threat, its credibility and the potential consequences. There has been no serious act of sabotage in the past nor an attempt of. Despite of this the Harnun attack of the Japanese underground and some other recent terrorist activities could have given reasons to reconsider what threat might be credible. The German physical protection system has been developed since the increasing terrorist activities in the 1970s. From the beginning the protection against sabotage played an important role in the German system of physical protection. The requirements for the physical protection against unauthorized removal and against sabotage were

  5. SU-E-T-243: Design of a Novel Testing Port for Radiation Protection and Shielding Measurements

    International Nuclear Information System (INIS)

    Tanny, S; Parsai, E; Harrell, D; Noller, J; Chopra, M

    2015-01-01

    Purpose: The majority of radiation shielding research utilizes Monte Carlo simulation because of the difficulty in eliminating secondary radiations from measurements. We have designed a test port into a primary barrier of our newest vault to allow for shielding measurements while ensuring adequate protection to the public and staff during normal machine operation. This port allows for measurement of attenuation values of shielding materials, differential dose albedos, and radiation scatter fractions. Methods: The vault design utilized the maze as part of a compound primary barrier. The test port is contained within the maze and is centered along isocenter. The inner 30 cm has a 20×20 cm 2 opening, while the remaining length has a 30×30 cm 2 opening. The block that contains the port has a density of 200 pcf to minimize internal scatter. The 30×30 cm 2 opening is occupied by removable 215 pcf concrete blocks. The innermost and outermost blocks activate an interlock wired into the beam-enable loop. This disallows beam-on in treatment mode if the interlock isn’t closed. The interlock can be overridden in service mode, or by-passed via an override switch in case of circuit failure. Results: The test port was installed in August. The beam is disabled when the interlock is tripped. Measurements taken when the primary beam is not incident on the port are indistinguishable from background. Ambient dose levels surrounding the vault with the designed shielding blocks in place are all within allowable limits for occupational workers. Conclusions: We have designed and installed a unique testing port for radiation protection and shielding measurements. This port is appropriately interlocked and designed to mitigate any risks of incidental exposure to staff or members of the public. The test port design allows measurements with “good geometry” and efficient removal of contaminating sources of radiation present in many shielding measurements. Daniel Harrell and Jim Noller

  6. [Eye lens radiation exposure during ureteroscopy with and without a face protection shield: Investigations on a phantom model].

    Science.gov (United States)

    Zöller, G; Figel, M; Denk, J; Schulz, K; Sabo, A

    2016-03-01

    Eye lens radiation exposure during radiologically-guided endoscopic procedures may result in radiation-induced cataracts; therefore, we investigated the ocular radiation exposure during ureteroscopy on a phantom model. Using an Alderson phantom model and eye lens dosimeters, we measured the ocular radiation exposure depending on the number of X-ray images and on the duration of fluoroscopic imaging. The measurements were done with and without using a face protection shield. We could demonstrate that a significant ocular radiation exposure can occur, depending on the number of X-ray images and on the duration time of fluoroscopy. Eye lens doses up to 0.025 mSv were recorded even using modern digital X-ray systems. Using face protection shields this ocular radiation exposure can be reduced to a minimum. The International Commission on Radiological Protection (ICRP) recommendations of a mean eye lens dosage of 20 mSv/year may be exceeded during repeated ureteroscopy by a high volume surgeon. Using a face protection shield, the eye lens dose during ureteroscopy could be reduced to a minimum in a phantom model. Further investigations will show whether these results can be transferred to real life ureteroscopic procedures.

  7. Radiation protection in nuclear energy. V.2

    International Nuclear Information System (INIS)

    1988-01-01

    The conference was convened to provide a forum for the exchange of international views on the principles of radiation protection for regulators and practitioners, to highlight issues of current importance, to examine the problems encountered in applying the principles of radiation protection, and, where possible, to identify generic solutions. The highlights of the conference were the sessions on the interface between nuclear safety and radiation protection, the evolution of radiation protection principles, exemption rules and accident experiences. The special session on the practical implications of the linear dose-response relationships also provoked particular interest. Although the session on optimization and decision aiding did not reveal any new developments, it did indicate an increasing emphasis on the optimization of radiation protection. A clear trend towards attaining lower collective doses per unit practice over a given time period, despite the increase in nuclear power plant capacity, is also apparent, although very few data on job-related worker doses have been published to date in the open literature. From the regulators' viewpoint, a very strong desire was expressed for a move towards regulatory strategies that exempt practices and sources causing insignificant individual and collective doses. Refs, figs and tabs

  8. Distributed systems for protecting nuclear power stations

    International Nuclear Information System (INIS)

    Jover, P.

    1980-05-01

    The advantages of distributed control systems for the control of nuclear power stations are obviously of great interest. Some years ago, EPRI, (Electric Power Research Institute) showed that multiplexing the signals is technically feasible, that it enables the availability specifications to be met and costs to be reduced. Since then, many distributed control systems have been proposed by the manufacturers. This note offers some comments on the application of the distribution concept to protection systems -what should be distributed- and ends with a brief description of a protection system based on microprocessors for the pressurized power stations now being built in France [fr

  9. Production of an economic high-density concrete for shielding megavoltage radiotherapy rooms and nuclear reactors

    International Nuclear Information System (INIS)

    Mortazavi, S. M. J.; Mosleh-Shirazi, M. A.; Maheri, M. R.; Haji-pour, A.; Yousefnia, H.; Zolghadri, S.

    2007-01-01

    In megavoltage radiotherapy rooms, ordinary concrete is usually used due to its low construction costs, although higher density concrete are sometimes used, as well. The use of high-density concrete decreases the required thickness of the concrete barrier; hence, its disadvantage is its high cost. In a nuclear reactor, neutron radiation is the most difficult to shield. A method for production of economic high-density concrete witt, appropriate engineering properties would be very useful. Materials and Methods: Galena (Pb S) mineral was used to produce of a high-density concrete. Galena can be found in many parts of Iran. Two types of concrete mixes were produced. The water-to-concrete (w/c) ratios of the reference and galena concrete mixes were 0.53 and 0.25, respectively. To measure the gamma radiation attenuation of Galena concrete samples, they were exposed to a narrow beam of gamma rays emitted from a cobalt-60 therapy unit. Results: The Galena mineral used in this study had a density of 7400 kg/m 3 . The concrete samples had a density of 4800 kg/m 3 . The measured half value layer thickness of the Galena concrete samples for cobalt 60 gamma rays was much less than that of ordinary concrete (2.6 cm compared to 6.0 cm). Furthermore, the galena concrete samples had significantly higher compressive strength (500 kg/cm 2 compared to 300 kg/cm 2 ). Conclusion: The Galena concrete samples made in our laboratories had showed good shielding/engineering properties in comparison with all samples made by using high-density materials other than depleted uranium. Based on the preliminary results, Galena concrete is maybe a suitable option where high-density concrete is required in megavoltage radiotherapy rooms as well as nuclear reactors

  10. Radiation protection at nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Endo, K.; Momose, T.; Furuta, S.

    2011-01-01

    Radiation protection methodologies concerning individual monitoring, workplace monitoring and environmental monitoring in nuclear fuel facilities have been developed and applied to facilities in the Nuclear Fuel Cycle Engineering Laboratories (NCL) of Japan Atomic Energy Agency (JAEA) for over 40 y. External exposure to photon, beta ray and neutron and internal exposure to alpha emitter are important issues for radiation protection at these facilities. Monitoring of airborne and surface contamination by alpha and beta/photon emitters at workplace is also essential to avoid internal exposure. A critical accident alarm system developed by JAEA has been proved through application at the facilities for a long time. A centralised area monitoring system is effective for emergency situations. Air and liquid effluents from facilities are monitored by continuous monitors or sampling methods to comply with regulations. Effluent monitoring has been carried out for 40 y to assess the radiological impacts on the public and the environment due to plant operation. (authors)

  11. The physical protection of nuclear material

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    Technical Committee met 21-25 June 1993 to consider changes to INFCIRC/225/Rev.2. The revised document, INFCIRC/225/Rev.3, reflects the Technical Committee recommendations for changes to the text as well as other modifications determined necessary to advance the consistency of the Categorization Table in INFCIRC/225/Rev.2 with the categorization table contained in The Convention of the Physical Protection of Nuclear Material and to reflect additional improvements presented by the experts. The recommendations presented in this IAEA document reflect a broad consensus among Member States on the requirements which should be met by systems for the physical protection of nuclear materials and facilities. It is hoped that they will provide helpful guidance for Member States.

  12. The physical protection of nuclear material

    International Nuclear Information System (INIS)

    1993-09-01

    Technical Committee met 21-25 June 1993 to consider changes to INFCIRC/225/Rev.2. The revised document, INFCIRC/225/Rev.3, reflects the Technical Committee recommendations for changes to the text as well as other modifications determined necessary to advance the consistency of the Categorization Table in INFCIRC/225/Rev.2 with the categorization table contained in The Convention of the Physical Protection of Nuclear Material and to reflect additional improvements presented by the experts. The recommendations presented in this IAEA document reflect a broad consensus among Member States on the requirements which should be met by systems for the physical protection of nuclear materials and facilities. It is hoped that they will provide helpful guidance for Member States

  13. Dictionary of radiation protection, radiobiology and nuclear medicine. English-German-French-Russian

    International Nuclear Information System (INIS)

    Sube, R.

    1985-01-01

    This multilingual dictionary covers the subject fields of radiation protection, radiobiology, and nuclear medicine with about 12,000 terms in each language. All terms are supplemented by one or more abbreviations of 22 special branches to assure the use of the very relevant terms. Special branches listed are for instance decontamination, dosimetry, atomic legislation, radiation detectors, radiography (medical), radiotherapy, safeguards, shielding, tansportation and storage. The terminology used in the International Nuclear Information System (INIS) of the IAEA has been completely taken into account

  14. Radiation shield ring assembly and method of disassembling components of a nuclear steam generator using such assembly

    International Nuclear Information System (INIS)

    Meuschke, R.E.; Wolfe, D.L.

    1982-01-01

    This invention relates to an apparatus and a method for cutting, within a shielding confinement, the irradiated components of a nuclear steam generator to reduce such components to a size to permit their subsequent removal from the containment structure of the generator

  15. Cathodic protection of a nuclear fuel facility

    International Nuclear Information System (INIS)

    Corbett, R.A.

    1989-01-01

    This article discusses corrosion on buried process piping and tanks at a nuclear fuel facility and the steps taken to design a system to control underground corrosion. Collected data have indicated that cathodic protection is needed to supplement the regular use of high-integrity, corrosion-resistant coatings; wrapping systems; special backfills; and insulation material. The technical approach discussed in this article is generally applicable to other types of power and/or industrial plants with extensive networks of underground steel piping

  16. Optimal Physical Protection against Nuclear Terrorism

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Doyoung; Kim, ChangLak [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2014-10-15

    There is no attempt with nuclear weapons to attack any places for terror or military victory since the atomic bombs dropped in Hiroshima and Nagasaki. People have obviously experienced horrible destructive power of nuclear weapons and continuously remembered a terrible tragedy, lots of organizations and experts express their concerns about the nuclear terrorism and try to interchange opinions for prevention of deadly weapons. The purpose of this paper is to provide the information of nuclear terrorism and what the potential risk of Republic of Korea is and how to do the efficient physical protection. Terror is from the old French terreur, which is derived from Latin verb terror meaning 'great fear'. This is a policy to suppress political opponents through using violence and repression. Many scholars have been proposed, there is no consensus definition of the term 'terrorism.' In 1988, a proposed academic consensus definition: 'Terrorism is an anxiety-inspiring method of repeated violent action, employed by (semi-) clandestine individual, group or state actors, for idiosyncratic, criminal or political reasons, whereby - in contrast to assassination - the direct targets of violence are not the main targets. The immediate human victims of violence are generally chosen randomly (targets of opportunity) or selectively (representative or symbolic targets) from a target population, and serve as message generators. These attacks showed that particular terrorists groups sought to cause heavy casualties and extreme terrorists were spontaneously prepared to make sacrifices for completion of that ultimate goal. Creation of nuclear weapons was like opening Pandora's box. Barack Obama has called nuclear terrorism 'the greatest danger we face'. Nuclear terror is one of the lethal risks. Using nuclear weapons or materials from terrorist groups is a fatal catastrophe to a targeting state though there is no accident similar like that. South

  17. Optimal Physical Protection against Nuclear Terrorism

    International Nuclear Information System (INIS)

    Lee, Doyoung; Kim, ChangLak

    2014-01-01

    There is no attempt with nuclear weapons to attack any places for terror or military victory since the atomic bombs dropped in Hiroshima and Nagasaki. People have obviously experienced horrible destructive power of nuclear weapons and continuously remembered a terrible tragedy, lots of organizations and experts express their concerns about the nuclear terrorism and try to interchange opinions for prevention of deadly weapons. The purpose of this paper is to provide the information of nuclear terrorism and what the potential risk of Republic of Korea is and how to do the efficient physical protection. Terror is from the old French terreur, which is derived from Latin verb terror meaning 'great fear'. This is a policy to suppress political opponents through using violence and repression. Many scholars have been proposed, there is no consensus definition of the term 'terrorism.' In 1988, a proposed academic consensus definition: 'Terrorism is an anxiety-inspiring method of repeated violent action, employed by (semi-) clandestine individual, group or state actors, for idiosyncratic, criminal or political reasons, whereby - in contrast to assassination - the direct targets of violence are not the main targets. The immediate human victims of violence are generally chosen randomly (targets of opportunity) or selectively (representative or symbolic targets) from a target population, and serve as message generators. These attacks showed that particular terrorists groups sought to cause heavy casualties and extreme terrorists were spontaneously prepared to make sacrifices for completion of that ultimate goal. Creation of nuclear weapons was like opening Pandora's box. Barack Obama has called nuclear terrorism 'the greatest danger we face'. Nuclear terror is one of the lethal risks. Using nuclear weapons or materials from terrorist groups is a fatal catastrophe to a targeting state though there is no accident similar like that. South

  18. Radiation Protection Programme in Nuclear Medicine Practice

    International Nuclear Information System (INIS)

    Alarfaj, Abd-I.M.

    2003-01-01

    This paper specifies the main elements of the radiation protection programma (RPP) that should be estabished for each practice, which involves radiation exposure. Practices of nuclear medicine have been considered as an example, since among the 245 installations which are conducting different practices with radiation sources in the Kingdom of Saudi Arabia, there are 78 installations dealing with nuclear medicine practices. Reviewing the RPP in these nuclear medicine installations, it may be easily concluded that the RPPs for the majority of these installations do not respond to the requirements of the regulatory body of the Kingdom, which is King Abdulaziz City for Science and Technology (KACST). This may be attributed to a set of different reasons, such as shortage in understanding the main elements of the RPP as well as in applying methodologies

  19. REACTOR SHIELD

    Science.gov (United States)

    Wigner, E.P.; Ohlinger, L.E.; Young, G.J.; Weinberg, A.M.

    1959-02-17

    Radiation shield construction is described for a nuclear reactor. The shield is comprised of a plurality of steel plates arranged in parallel spaced relationship within a peripheral shell. Reactor coolant inlet tubes extend at right angles through the plates and baffles are arranged between the plates at right angles thereto and extend between the tubes to create a series of zigzag channels between the plates for the circulation of coolant fluid through the shield. The shield may be divided into two main sections; an inner section adjacent the reactor container and an outer section spaced therefrom. Coolant through the first section may be circulated at a faster rate than coolant circulated through the outer section since the area closest to the reactor container is at a higher temperature and is more radioactive. The two sections may have separate cooling systems to prevent the coolant in the outer section from mixing with the more contaminated coolant in the inner section.

  20. Evaluation of radiation protection in some nuclear medicine department

    International Nuclear Information System (INIS)

    Abdelrahim, Yassir Mohammed

    2015-12-01

    This study was carryout to evaluate the radiation protection in nuclear medicine department in Sudan, accordance with the standards international recommendation and code of practice for radiation protection in nuclear medicine, the evaluation was done for three nuclear medicine departments, included direct measurement of dose rate and the contamination level in some areas, were radiation sources, radiation workers and public are involved. The data was collected and analyzed from the results for three nuclear medicine departments that the average reading of ambient dose rate in : outside the door of imaging room (SPECT) 0.18μSv/h in hospital (1)& and 0.19μSv/h in hospital(2) and 0.19μSv/h hospital(3), inside control of imaging room (SPECT) 27.8μSv/h in hospital(1)& 0.14μSv/h in hospital(2)& 14μSv/h in hospital(3), inside the injection room 28.81μSv/h in hospital(1), 0.36μSv/h in hpspital(2), 0.06μSv/h in hospital(3) outside the door of lap, 0.65μSv/h in hospital(1), 0.13μSv/h in hospital(2) & 0.12μSv/h in hospital(3), inside the hot lap, 9.68μSv/h in hospital(1) & 0.30μSv/h in hospital(2) & 0.85 μSv/h in hospital(3), in outsidee the door of waiting room of injected patient 1.41μSv/h in hospital(1)& 0.16μSv/h in hospital(2) & 1.08μSv/h in hospital(3). Avaerge reading of contamination in: Floor of hot lap 44.50 B/cm"2 hospital(1) & 4.42B/cm"2in hospital(2) & 6.22 B/cm"2 in hospital (3) . on the bench tap 186.30 B/cm"2 hospital(1), 19.91 B/cm"2 in hospital(2) & 8.77B/cm"2 in hospital(3) floor of injection room 12.60 B/cm"2 in hospital(1) & 11.70 B/cm"2 in hospital(2) & 13.73 B/cm"2 hospital(3) & table of injection room 13.00 B/cm"2 in hospital(1)& 11.70 B/cm"2in hospital(2)& 13.73 B/cm"2 in hospital & tble of injection room 13.00 B/cm"2 in hospital(1) & 20.40 B/cm"2 in hospital(2) & 23.23 B/cm"2 B/cm"2 in hospital(3) on the shield of working surface 144.30 B/cm in hospital(1)& 47.00 B/cm"2 in hospital(2) & 52.33 B/cm"2 in hospital(3) , and makes check

  1. Experimental Studies on Shadow Shields for Thermal Protection of Cryogenic Tanks in Space

    National Research Council Canada - National Science Library

    Knoll, Richard

    1968-01-01

    ... (high-emissivity coatings on annular rings of shields) on thermal performance. The experimental data, in general, agreed closely with an analytical model which assumed diffuse surfaces with nonuniform radiosity...

  2. Protection against nuclear terrorism: the IAEA response

    International Nuclear Information System (INIS)

    Dodd, B.

    2002-01-01

    Full text: As a result of the events of 11 September 2001, the International Atomic Energy Agency (IAEA) identified possible threats from acts of nuclear terrorism. A report to the Board of Governors in November 2001 summarized the IAEA's ongoing work in areas relevant to the prevention and mitigation of the consequences of such acts and outlined proposals for a number of new and/or enhanced activities. Four main threats were addressed: theft of a nuclear weapon; acquisition of nuclear material; acquisition of other radioactive material; and violent acts against nuclear facilities. These proposals have been further refined and the new plan was approved in principle at the March 2002 board meeting. In the beginning, implementation will be dependent on member state contributions to a voluntary fund. Proposed new or enhanced activities are grouped into eight areas: I. Physical protection of nuclear material and nuclear facilities; II. Detection of malicious activities involving nuclear and other radioactive materials; III. State systems for nuclear material accountancy and control; IV. Security of radioactive material other than nuclear material; V. Assessment of safety/security related vulnerability of nuclear facilities; VI. Response to malicious acts, or threats thereof; VII. Adherence to and implementation of international agreements, guidelines and recommendations; VIII. Nuclear security co-ordination and information management. After an overview, this paper focuses on activity area IV, which deals with the radiological terrorism issues involving radioactive sources. A strategy for evaluation of the IAEA's role is presented, covering an analysis of the likely threats and possible scenarios. This leads to an assessment of the most desirable sources from a terrorist's viewpoint. The strategy then examines how terrorists might acquire such sources and attempts to determine the best ways to prevent their acquisition. Further activities are proposed to prevent the use

  3. SU-F-I-72: Evaluation of the Ancillary Lead Shielding for Optimizing Radiation Protection in the Interventional Radiology Department

    Energy Technology Data Exchange (ETDEWEB)

    Tonkopi, E; Lightfoot, C [Dalhousie University, Queen Elizabeth II Health Sciences Ctr, Halifax, NS (Canada); LeBlanc, E [Queen Elizabeth II Health Sciences Ctr, Halifax, NS (Canada)

    2016-06-15

    Purpose: The rising complexity of interventional fluoroscopic procedures has resulted in an increase of occupational radiation exposures in the interventional radiology (IR) department. This study assessed the impact of ancillary shielding on optimizing radiation protection for the IR staff. Methods: Scattered radiation measurements were performed in two IR suites equipped with Axiom Artis systems (Siemens Healthcare, Erlangen, Germany) installed in 2006 and 2010. Both rooms had suspended ceiling-mounted lead-acrylic shields of 75×60 cm (Mavig, Munich, Germany) with lead equivalency of 0.5 mm, and under-table drapes of 70×116 cm and 65×70 cm in the newer and the older room respectively. The larger skirt can be wrapped around the table’s corner and in addition the newer suite had two upper shields of 25×55 cm and 25×35 cm. The patient was simulated by 30 cm of acrylic, air kerma rate (AKR) was measured with the 180cc ionization chamber (AccuPro Radcal Corporation, Monrovia, CA, USA) at different positions. The ancillary shields, x-ray tube, image detector, and table height were adjusted by the IR radiologist to simulate various clinical setups. The same exposure parameters were used for all acquisitions. AKR measurements were made at different positions relative to the operator. Results: The AKR measurements demonstrated 91–99% x-ray attenuation by the drapes in both suites. The smaller size of the under-table skirt and absence of the side-drapes in the older room resulted in a 20–50 fold increase of scattered radiation to the operator. The mobile suspended lead-acrylic shield reduced AKR by 90–94% measured at 150–170 cm height. The recommendations were made to replace the smaller under-table skirt and to use the ceiling-mounted shields for all IR procedures. Conclusion: The ancillary shielding may significantly affect radiation exposure to the IR staff. The use of suspended ceiling-mounted shields is especially important for reduction of

  4. About the Scythian Shields

    Directory of Open Access Journals (Sweden)

    About the Scythian Shields

    2017-10-01

    Full Text Available Shields played major role in the armament system of the Scythians. Made from organic materials, they are poorly traced on the materials of archaeological excavations. Besides, scaly surface of shields was often perceived in practice as the remnants of the scaly armor. E. V. Chernenko was able to discern the difference between shields’ scaly plates and armor scales. The top edge of the scales was bent inwards, and shield plates had a wire fixation. These observations let significantly increase the number of shields, found in the burial complexes of the Scythians. The comparison of archaeological materials and the images of Scythian warriors allow distinguishing the main forms of Scythian shields. All shields are divided into fencing shields and cover shields. The fencing shields include round wooden shields, reinforced with bronze sheet, and round moon-shaped shields with a notch at the top, with a metal scaly surface. They came to the Scythians under the Greek influence and are known in the monuments of the 4th century BC. Oval shields with scaly surface (back cover shields were used by the Scythian cavalry. They protected the rider in case of frontal attack, and moved back in case of maneuver or closein fighting. Scythian battle tactics were based on rapid approaching the enemy and throwing spears and further rapid withdrawal. Spears stuck in the shields of enemies, forcing them to drop the shields, uncover, and in this stage of the battle the archers attacked the disorganized ranks of the enemy. That was followed by the stage of close fight. Oval form of a wooden shield with leather covering was used by the Scythian infantry and spearmen. Rectangular shields, including wooden shields and the shields pleached from rods, represented a special category. The top of such shield was made of wood, and a pleached pad on leather basis was attached to it. This shield could be a reliable protection from arrows, but it could not protect against javelins

  5. Protective effect of building against nuclear fallout

    International Nuclear Information System (INIS)

    Mueck, K.; Lovranich, E.; Steger, F.

    1995-02-01

    In order to adopt appropriate countermeasures to protect the public in case of a wide-spread contamination after a severe reactor accident, a profound knowledge of the dose to be expected and of the dose reduction to be expected if a specific countermeasure is adopted is required. Since external radiation contributes a major fraction of up to 80 % to the total dose, the interest is focused on the reduction of external dose by staying indoors. For this purpose measurements of the dose reduction by external radiation were performed in 40 residential rooms in Vienna which were chosen according to their fraction of the Viennese building structure. They were performed by measurement of the reduction of the gamma-flux in the interior of buildings compared to the gamma-flux outside. Measurements were carried out by a HPGe-detector which was positioned 1 m above ground. The observed dose reduction factors amounted to 0.013 on the average (protection factor 78.7 ± 49.7), with the protection factors of the investigated building types ranging from 6.5 (single house in garden) to 122.9 (edicifices of the turn of the century). The observed protection factors do not include the dose reduction by dense arrangement of buildings in urban areas which has to be considered separately. The dose reduction due to different radionuclide mixtures after severe reactor accidents was also investigated. Factors similar to that observed for Cs-137 were found. The maximum deviations amounted only 12 % and therefore may be neglected in the consideration of protective measures. Additional measurements were performed with the same detector shielded by lead on all sides to determine the contribution of the interior contamination. A contribution of between < 10 % to 50 % to the external dose in the interior of buildings was observed. Measures to reduce the inner contamination in rooms (closing of windows and doors, cleaning upon entering the building interior) in case of an event are therefore

  6. Training in radiological protection for nuclear programmes

    International Nuclear Information System (INIS)

    1975-01-01

    Many Member States are developing or already have developed their own national training programmes. The IAEA is actively involved in promoting training in radiological protection for nuclear programmes. The various types of training are fully discussed, with suggested curricula. An earlier report was published as Technical Reports Series No.31 in 1964. In 1973, new and additional information was received from Member States which is reflected in the present report. Training programmes are classified, according to those requiring training: specialists; persons whose work is closely related to radiological protection (administrators, public health officers and industrial health personnel, safety inspectors and engineers in nuclear installations, public service personnel); persons working with radiation; and the general public. Forms, scope and duration of training are discussed. Different types of training programmes are currently required for training of medical doctors (those providing medical surveillance for radiation workers and others dealing with public health aspects of radiation hazards), for technical supervisors, radiologists, and qualified workers in nuclear medicine, technological staff, administrators, persons working with radiation, and public service personnel. Standard curricula and desirable experiments and exercises are discussed. The organization of training together with the facilities, equipment and teaching staff required are considered, as is follow-up training. Annexes 1 to 4 give examples of training curricula and training courses available in various countries, a suggested syllabus for training of technical supervisors, and a bibliography consisting of 210 references dealing with general topics, nuclear radiation physics, radiochemistry and radiation chemistry, radiation biology and biophysics, dosimetry and health physics and radiation protection, medical aspects and toxicology, and environmental aspects

  7. Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Swadling, G. F.; Ross, J. S.; Datte, P.; Moody, J.; Divol, L.; Jones, O.; Landen, O. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-11-15

    An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause “blanking” (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ∼8 J cm{sup −2}. This is significantly above the expected threshold for the onset of “blanking” effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate “blanking.” Estimates suggest that an areal density of 10{sup 19} cm{sup −2} Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

  8. Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic.

    Science.gov (United States)

    Swadling, G F; Ross, J S; Datte, P; Moody, J; Divol, L; Jones, O; Landen, O

    2016-11-01

    An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause "blanking" (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ∼8 J cm -2 . This is significantly above the expected threshold for the onset of "blanking" effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate "blanking." Estimates suggest that an areal density of 10 19 cm -2 Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

  9. Data for radiation protection and nuclear data

    International Nuclear Information System (INIS)

    Yamaguchi, Yasuhiro; Endo, Akira; Sakamoto, Yukio

    2001-01-01

    Various conversion coefficients have been used in external and internal dosimetry in radiation protection practices. Radiation doses in the human body cannot be directly measured in general situation and the conversion coefficient has been used to correlate the human body dose with physical quantities such as radioactivity, particle fluence and other dosimetric quantities to be used to describe the radiation field. Fluence-to-organ dose conversion coefficients have been calculated using Monte Carlo radiation transport codes in conjunction with an anthropomorphic mathematical phantom. Neutron and photon interaction cross-section libraries are indispensable for these calculations. ICRP Publication 74 gives tables of conversion coefficients for estimation of organ doses and effective dose for photons, neutrons and electrons. Based on these results, shielding calculation parameters have been prepared for simple and easy dose estimation in radiation facilities. Dose factors, organ doses and effective dose per unit intake of radionuclide, have been also calculated for internal dosimetry purpose. ICRP Publications 68 and 72 give tables of dose factors for a variety of radionuclides. Revision of radiation data library has been made to reflect updated information on radionuclides to internal dosimetry. (author)

  10. Radiation shielding performance of some concrete

    International Nuclear Information System (INIS)

    Akkurt, I.; Akyildirim, H.; Mavi, B.; Kilincarslan, S.; Basyigit, C.

    2007-01-01

    The energy consumption is increasing with the increased population of the world and thus new energy sources were discovered such as nuclear energy. Besides using nuclear energy, nuclear techniques are being used in a variety of fields such as medical hospital, industry, agriculture or military issue, the radiation protection becomes one of the important research fields. In radiation protection, the main rules are time, distance and shielding. The most effective radiation shields are materials which have a high density and high atomic number such as lead, tungsten which are expensive. Alternatively the concrete which produced using different aggregate can be used. The effectiveness of radiation shielding is frequently described in terms of the half value layer (HVL) or the tenth value layer (TVL). These are the thicknesses of an absorber that will reduce the radiation to half, and one tenth of its intensity respectively. In this study the radiation protection properties of different types of concrete will be discussed

  11. Radiation shielding and criticality safety assessment for KN-12 spent nuclear fuel transport cask

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Kyung; Shin, Chang Ho; Kim, Gi Hwan [Hanyang Univ., Seoul (Korea, Republic of)

    2001-08-15

    Because SNFs involve TRU (Transuranium), fission products, and fissile materials, they are highly radioactive and also have a possibility to be critical. Therefore, radiation shielding and criticality safety for transport casks containing the SNFs should be guaranteed through reliable valuation procedure. IAEA safety standard series No ST-1 recommends regulation for safe transportation of the SNFs by transport casks, and United States is carrying out it according to the regulation guide, 10 CFR parts 71 and 72. Present research objective is to evaluate the KN-12 spent nuclear fuel transport cask that is designed for transportation of up to 12 assemblies and is standby status for being licensed in accordance with Korea Atomic Energy Act. Both radiation shielding and criticality analysis using the accurate Monte Carlo transport code, MCNP-4B are carried out for the KN-12 SNF cask as a benchmark calculation. Source terms for radiation shielding calculation are obtained using ORIGEN-S computer code. In this work, for normal transport conditions, the results from MCNP-4B shows the maximum dose rate of 0.557 mSv/hr at the side surface. And the maximum dose rate of 0.0871 mSv/hr was resulted at the 2 m distance from the cask. The level of calculated dose rate is 27.9% of the limit at the cask surface, 87.1% at 2 m from the cask surface for normal transport condition. For hypothetical accident conditions, the maximum rate of 2.5144 mSv/hr was resulted at the 1 m distance from the cask and this level is 25.1% of the limit for hypothetical accident conditions. In criticality calculations using MCNP-4B, the k{sub eff} values yielded for 5.0 w/o U-235 enriched fresh fuel are 0.92098 {+-} 0.00065. This result confirms subcritical condition of the KN-12 SNF cask and gives 96.95% of recommendations for criticality safety evaluation by US NRC these results will be useful as a basis for approval for the KN-12 SNF cask.

  12. Optimized shielding calculation to the transport of 131I employed in nuclear medicine

    International Nuclear Information System (INIS)

    Sahyun, A.; Sordi, G.M.; Rodrigues, D.; Sanches, M.P.; Romero F, C.R.

    1996-01-01

    The objective of this paper is to present the basis for shielding calculation used in different situations that could occur during the transport of 131 I utilized in nuclear medicine for diagnostic and therapeutic purposes. The aim of these calculation is to optimize the shielding in order to satisfy the transport of radioactive material. These calculations were proposed for estimated activities around 1,85 GBq (50mCi), 3,7 GBq(100mCi) and 7,4 GBq(200mCi), considering the driver of the cargo company and his assistant as the critical group and the general people considered as effect of collective dose. The population density considered in the models is the one related to Sao Paulo city, because the transport is done by the highway across the city and the radioactive material is distributed from west to north and south, where the airports are located. This area ranges a perimeter of 40 km. For the collective dose calculation, it was considered a population dose of less than 1/100 of the annual limit dose for the public. Our main concern is related to the large volume of radioactive material that is transported per week, specially because 1/3 of this material has activities around 3,7 GBq (100mCi). During the calculations, we have figured out that the activities at the moment of transport are nearly 40% greater than the one related to the calibration date. As for the discrepancy of official alpha value of US$10000/man-Sv and the real value for our country of US$3000/man-Sv,a comparative study was performed. (authors). 3 refs., 2 figs., 2 tabs

  13. Protection of nuclear facilities against outer aggressions

    International Nuclear Information System (INIS)

    Aussourd, P.; Candes, P.; Le Quinio, R.

    1976-01-01

    The various types of outer aggressions envisaged in safety analysis for nuclear facilities are reviewed. These outer aggressions are classified as natural and non-natural phenomena, the latter depending on the human activities in the vicinity of nuclear sites. The principal natural phenomena able to constitute aggressions are atmospheric phenomena (strong winds, snow storms, hail, frosting mists), hydrologie phenomena such as tides, surges, flood, low waters, and geologic phenomena such as earthquakes. Artificial phenomena are concerned with aircraft crashes, projectiles, fire, possible ruptures of dams, and intentional human aggressions. The protection against intentional human aggressions is of two sorts: first, the possibility of access to the installations mostly sensitive to sabotage are to be prevented or reduced, secondly redundant circuits and functions must be separated for preventing their simultaneous destruction in the case when sabotage actors have reach the core of the facility [fr

  14. Radiometric determination of density of fresh shielding concrete (in situ) in the nuclear industry

    International Nuclear Information System (INIS)

    Honig, A.

    1985-01-01

    Methods of radiometric determination of density have been in recent years elaborated in detail and successfully. But on the market no instruments are available for measuring fresh concrete when it is possible to repair inhomogeneities, if any, even before hardening, and thus to guarantee safety of biological protection of nuclear reactors. The paper describes an analog and digital radiation density meter and their application in the inspection of radiation protection concrete walls. By repairing defective, insufficiently dense locations still in the course of concrete placement it is possible to attain a laboratory quality of the concrete even under on-site conditions

  15. SNAP: a tool for nuclear physical protection system modeling

    International Nuclear Information System (INIS)

    Engi, D.; Grant, F.H. III.

    1979-10-01

    Nuclear safeguards systems are concerned, in part, with the physical protection of nuclear materials. The function of a physical protection system is to define the facility against adversary activities which could lead to theft of nuclear material or sabotage resulting in a radiological release. The Safeguards Network Analysis Procedure (SNAP) provides a convenient and standard analysis methodology for the evaluation of physical protection system analysis. This paper describes a detailed application of SNAP to a hypothetical nuclear facility

  16. Environmental protection and nuclear energy. 4. ed.

    International Nuclear Information System (INIS)

    1990-01-01

    The present energy supply has to be reconsidered based on the continous increase of CO 2 -concentration in the air. For this, questions on environmental protection, nuclear energy, safety of usable plants and estimation of technical subsequences serve for contributions to a discussion as a result of the consideration, 10 theses on an ethic of energy technology have been elaborated. The Union of Catholic Employers is considered that the improved reactor technology has a new chance in our country. The minimization of risks and damages of this technology has proceeded in a way that it can be shared with regard to Christian responsibility. (orig./DG) [de

  17. Protective underpressure system for nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    A vacuum protection system for a nuclear reactor is described containng the possible accident in the immediate area where it happened. The system uses underpressure in the air-tight primary circuit jacket. Immediately after the accident, part of air is forced out from the area where coolant is being lost to another area which is then separated from the accident area. The desired underpressure is attained by steam condensation. A system diagram is shown and the time-dependent pressure changes in the contained areas are presented. (J.B.)

  18. Nuclear terrorism and legal protection of environment

    International Nuclear Information System (INIS)

    Ahmad-zada, Z.; Aliev, D.

    2003-01-01

    Full text: For the last years the terrorism has significantly changed. If 20-30 years ago terrorists would kidnap famous politicians or hijack planes, but at this stage they switched to massive destruction of innocent people. Now the problem of struggle against nuclear terrorism becomes very actual problem. The nuclear terrorism is meant as an opportunity of accomplishment of act of terrorism with use of the nuclear weapon, or accomplishment of explosions on atomic power stations and other objects of an atomic energy. Threats to nuclear objects become more and more often and appreciable. In the world there were some similar cases of threat to nuclear objects from the part of terrorists, and also cases of use by terrorists of nuclear, chemical and bacteriological substances. These cases testify to real threat of use by terrorists of the weapon of mass destruction. It is natural, that accomplishment of acts of terrorism on these objects can lead to ecological catastrophe and can put an irreparable loss to an environment and process of social development. Up to the middle of sixtieth years of twentieth century protection of an environment was not put forward as an independent political problem, and its scientific substantiation has not been developed enough as a diversified, complex, global problem. Only dynamical development in seventieth - eightieth years of scientific bases of global problems has allowed to allocate the rules of law concerning to protection of an environment, into special group. International legal protection of ecology was precisely allocated now in system of the general international law as independent, specific sphere of regulation. The principle of inadmissibility of radioactive pollution of environment covers both military, and peace area of use of nuclear power. Formation and the statement of this special principle of International law of the Environment takes place in two ways - contractual and usual, with observance by the states of

  19. Radiological protection in nuclear power plants

    International Nuclear Information System (INIS)

    Zorrilla R, S.

    2008-12-01

    This presentation sharing experiences which correspond to the nuclear power plant of Laguna Verde. This nuclear power plant is located at level 2 of four possible, in the classification performance of the World Association of Nuclear Operators (WANO), which means the mexican nuclear power plant is classified in terms of its performance indicators and above the average achieved by their counterparts americans and canadians. In the national context, the nuclear power plant of Laguna Verde has also been honored with several awards such as the National Quality Award, the Clean Industry Certificate, the distinction of Environmental Excellence and others of similar importance. For the standards of WANO, the basic idea is that there are shortcomings in one of nuclear power plant concern to all partners. The indicators used for the classification will always go beyond more compliance with regulations, which are assumed, and rather assume come or a path to excellence. Among the most important indicators are: the collective dose, the percentage of areas declared as contaminated, the number, type and tendency of contamination personal cases, the number of dosimetry alarms, the number of unplanned exposures, loss control of high radiation areas and the release of contaminated material outside the restricted areas. Furthermore, as already indicated, nuclear power plants are of special care situations, such as, carrying out work in areas with radiation fields of more than 15 mSv h -1 , the movement of spent fuel in the reload floor. The consideration of the minimum total effective dose equivalent as a criterion for prescribing tools that reduce exposures, but may increase the external cases of contaminated casualties, the experience in portals such as workers subject to radiology, where exposure in industrial radiography, and so on. Special mention deserve the conditions generated during fuel reload stops, which causes a massive personnel movement, working simultaneously on

  20. The convention on the physical protection of nuclear material

    International Nuclear Information System (INIS)

    1980-05-01

    This document contains the full text of a convention to facilitate the safe transfer of nuclear material, and to insure the physical protection of nuclear material in domestic use, storage, and transport. Two annexes are included, which establish categories of nuclear materials and levels of physical protection to be applied in international transport

  1. Radiation shielding lead shield

    International Nuclear Information System (INIS)

    Dei, Shoichi.

    1991-01-01

    The present invention concerns lead shields for radiation shielding. Shield boxes are disposed so as to surround a pipeline through which radioactive liquids, mists or like other objects are passed. Flanges are formed to each of the end edges of the shield boxes and the shield boxes are connected to each other by the flanges. Upon installation, empty shield boxes not charged with lead particles and iron plate shields are secured at first at the periphery of the pipeline. Then, lead particles are charged into the shield boxes. This attains a state as if lead plate corresponding to the depth of the box is disposed. Accordingly, operations for installation, dismantling and restoration can be conducted in an empty state with reduced weight to facilitate the operations. (I.S.)

  2. Facilities inventory protection for nuclear facilities

    International Nuclear Information System (INIS)

    Schmitt, F.J.

    1989-01-01

    The fact that shut-down applications have been filed for nuclear power plants, suggests to have a scrutinizing look at the scopes of assessment and decision available to administrations and courts for the protection of facilities inventories relative to legal and constitutional requirements. The paper outlines the legal bases which need to be observed if purposeful calculation is to be ensured. Based on the different actual conditions and legal consequences, the author distinguishes between 1) the legal situation of facilities licenced already and 2) the legal situation of facilities under planning during the licencing stage. As indicated by the contents and restrictions of the pertinent provisions of the Atomic Energy Act and by the corresponding compensatory regulation, the object of the protection of facilities inventor in the legal position of the facility owner within the purview of the Atomic Energy Act, and the licensing proper. Art. 17 of the Atomic Energy Act indicates the legislators intent that, once issued, the licence will be the pivotal point for regulations aiming at protection and intervention. (orig./HSCH) [de

  3. Nuclear safety and radiation protection in France in 2011

    International Nuclear Information System (INIS)

    2012-01-01

    The first part of this voluminous report describe the different ASN (Nuclear Safety Authority) actions: nuclear activities (ionising radiation and health and environmental risks), principles and stakeholders in nuclear safety regulation, radiation protection and protection of the environment, regulation, regulation of nuclear activities and exposure to ionizing radiation, radiological emergencies, public information and transparency, international relations. It also gives an overview of nuclear safety and radiation protection activities in the different French regions. The second part addresses activities regulated by the ASN: medical uses of ionizing radiation, non-medical uses of ionizing radiation, transport of radioactive materials, nuclear power plants, nuclear fuel cycle installations, nuclear research facilities and various nuclear installations, safe decommissioning of basic nuclear installations, radioactive waste and contaminated sites and soils

  4. Radiological Protection of Patients in Nuclear Medicine

    International Nuclear Information System (INIS)

    Rojo, A.M.

    2011-01-01

    Full text: This lecture aims at presenting the state of the art of radiological protection of patients in nuclear medicine focusing on three aspects of interest where to achieve improvement. The hierarchy of the justification principle of the radiation protection is one of them. There seems for a change to be presented in the paradigm of the radiological protection of patients. The role of the physician who prescribes the medical practice becomes more relevant, together with the nuclear medicine specialist who should be co-responsible for the application of this justification principle. Regarding the doses optimization and the implementation of Dose Reference Level the involvement extends far beyond the physician and radioprotection officer. It is clear that the Medical Physicist is to play a very relevant role in the coordination of actions, as the nuclear medicine technician is to execute them. Another aspect to consider is patient specific dosimetry. It should become a routine practice through calculation of the absorbed dose based on biodistribution data. It should be assessed for each individual patient, as it depends on a number of patient-specific parameters, such as gender, size and the amount of fatty tissue in the body, as well as the extent and nature of the disease. In most cases, dosimetry calculations are not carried out and patients are administered standard levels of activity. There may be situations with a lack of knowledge on internal dosimetry as in many centers either none or only one or two medical physics experts are available. It shows that a formal training for experts in internal dosimetry at national level is required. However up to now, there has been no satisfactory correlation between absorbed dose estimates and patient response. Moreover, the radiation protection for the patient is not assured, as the dose values given are often numbers without connection to radiobiological and/or hematological findings. Pending tasks related to

  5. Calculations of atomic magnetic nuclear shielding constants based on the two-component normalized elimination of the small component method

    Science.gov (United States)

    Yoshizawa, Terutaka; Zou, Wenli; Cremer, Dieter

    2017-04-01

    A new method for calculating nuclear magnetic resonance shielding constants of relativistic atoms based on the two-component (2c), spin-orbit coupling including Dirac-exact NESC (Normalized Elimination of the Small Component) approach is developed where each term of the diamagnetic and paramagnetic contribution to the isotropic shielding constant σi s o is expressed in terms of analytical energy derivatives with regard to the magnetic field B and the nuclear magnetic moment 𝝁 . The picture change caused by renormalization of the wave function is correctly described. 2c-NESC/HF (Hartree-Fock) results for the σiso values of 13 atoms with a closed shell ground state reveal a deviation from 4c-DHF (Dirac-HF) values by 0.01%-0.76%. Since the 2-electron part is effectively calculated using a modified screened nuclear shielding approach, the calculation is efficient and based on a series of matrix manipulations scaling with (2M)3 (M: number of basis functions).

  6. Establishment of radiation protection and safety programme in Nuclear Medicine

    International Nuclear Information System (INIS)

    Chene, E.

    2014-04-01

    Radiation is useful because of its ability to penetrate tissue, allowing imaging of internal structures. However radiation may produce harmful biological effects. Observations of exposed human populations and animal experimentation indicate that exposure to low levels of radiation over a period of time may lead to stochastic radiation effects. Exposures to high levels of radiation above threshold also leads to deterministic effects. Establishment of radiation protection and safety programme and implement it without fail may help prevent deterministic effect and limit chances of stochastic effects. This is achieved by assigning responsibilities to the proposed organizational structure, management commitment to safety culture by providing continuous education and training to employees, regular reviewing and auditing of radiation safety policies. Occupational, public and environmental radiation exposure is further achieved by implementation of set local rules and operational procedures, proper management of radioactive waste and safe transport of radioactive material. Medical radiation exposure is achieved by justified procedures, optimization of doses, guidance levels, quality assurance and quality control programme through image quality, radiopharmaceutical quality and records keeping of radiation doses, calibration certificates of equipment used, equipment service and test certificates. Diagnostic radiopharmaceuticals must deliver the minimum possible radiation dose to the patient while therapeutic radiopharmaceuticals must deliver the maximum dose to the target organ or tissue, while minimizing the dose to non-target tissues such as the bone marrow. Special considerations shall be given to pregnant and breast-feeding patients. The proper facility design and shielding of a nuclear medicine facility shall further provide for the radiation protection to the worker, the patient, public and the environment. Precautions should be given to radioactive patients as there

  7. Annual report 1996 concerning the nuclear safety and radiological protection in the Swiss nuclear installations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    The report presents detailed information about the nuclear safety and radiological protection in the Swiss nuclear power plants, the central interim storage at Wuerenlingen, the Paul Scherrer Institute (PSI) and other nuclear installations in Switzerland. figs., tabs., refs.

  8. Annual Report 1998 concerning the nuclear safety and radiological protection in the Swiss nuclear installations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The report presents detailed information about the nuclear safety and radiological protection in the Swiss nuclear power plants, the central interim storage at Wuerenlingen, the Paul Scherrer Institute (PSI) and other nuclear installations in Switzerland.

  9. Annual Report 1998 concerning the nuclear safety and radiological protection in the Swiss nuclear installations

    International Nuclear Information System (INIS)

    1999-05-01

    The report presents detailed information about the nuclear safety and radiological protection in the Swiss nuclear power plants, the central interim storage at Wuerenlingen, the Paul Scherrer Institute (PSI) and other nuclear installations in Switzerland

  10. Annual Report 1999 concerning the nuclear safety and radiological protection in the Swiss nuclear installations

    International Nuclear Information System (INIS)

    2000-08-01

    The report presents detailed information about the nuclear safety and radiological protection in the Swiss nuclear power plants, the central interim storage at Wuerenlingen, the Paul Scherrer Institute (PSI) and other nuclear installations in Switzerland

  11. Annual Report 1999 concerning the nuclear safety and radiological protection in the Swiss nuclear installations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-08-15

    The report presents detailed information about the nuclear safety and radiological protection in the Swiss nuclear power plants, the central interim storage at Wuerenlingen, the Paul Scherrer Institute (PSI) and other nuclear installations in Switzerland.

  12. Annual report 1996 concerning the nuclear safety and radiological protection in the Swiss nuclear installations

    International Nuclear Information System (INIS)

    1997-05-01

    The report presents detailed information about the nuclear safety and radiological protection in the Swiss nuclear power plants, the central interim storage at Wuerenlingen, the Paul Scherrer Institute (PSI) and other nuclear installations in Switzerland. figs., tabs., refs

  13. National practices in physical protection of nuclear materials. Regulatory basis

    International Nuclear Information System (INIS)

    Goltsov, V.Y.

    2002-01-01

    Full text: The Federal law 'On The Use Of Atomic Energy' containing the section on physical protection of nuclear materials and nuclear facilities was issued in 1995 in Russian Federation. This document became the first federal level document regulating the general requirements to physical protection (PP). The federal PP rules developed on the base of this law by Minatom of Russia and other federal bodies of the Russian Federation were put in force by the government of Russia in 1997. The requirements of the convention on physical protection of nuclear materials (INFCIRC 274) and the modern IAEA recommendations (INFCIRC/225/Rev.4) are taken into account in the PP rules. Besides, while developing the PP rules the other countries' experience in this sphere has been studied and taken into account. The PP rules are action-obligatory for all juridical persons dealing with nuclear activity and also for those who are coordinating and monitoring this activity. Nuclear activity without physical protection ensured in accordance with PP rules requirements is prohibited. The requirements of PP Rules are stronger than the IAEA recommendations. The PP rules are establishing: physical protection objectives; federal executive bodies and organizations functions an implementation of physical protection; categorization of nuclear materials; requirements for nuclear materials physical protection as during use and storage as during transportation; main goals of state supervision and ministry level control for physical protection; notification order about the facts of unauthorized actions regarding nuclear materials and facilities. Besides the above mentioned documents, there were put in force president decrees, federal laws and regulations in the field of: counteraction to nuclear terrorism; interactions in physical protection systems; military and ministerial on-site guard activities; information protection. By the initiative of Minatom of Russia the corrections were put into the

  14. Protection of nuclear facilities and nuclear materials against malevolent actions

    International Nuclear Information System (INIS)

    Cornu, P.; Aurelle, J.; Jalouneix, J.

    2001-01-01

    The french approach for considering malevolent actions affecting the design and operation of nuclear facilities is aimed at determining the extent to which the facilities are protected. When carrying out these studies, operating organizations have to demonstrate that their are complying with the objectives set by the Competent Authority for reducing the risk of internal or external malevolent actions. The approach to be followed consist to determine the sensitivity of each zone and to estimate the vulnerability of the most critical zones to each type of aggression. The sensitivity can be defined by the level of the radiological consequences resulting from a malevolent action. The estimation of the vulnerability is made of the extent to which it is difficult to carry out a malevolent action. if need be, counter-measures are taken to protect zones for which the consequences would be unacceptable compared to the force of the aggression. Counter-measures are intended both to minimise sensitivity and make it more difficult to carry out the aggression envisaged. Acceptable consequences are taken as being those leading to levels of radioactive releases less than, or equal to, those taken into account in the facility safety case. This implies that the vulnerability of the most sensitive zones should be reduced to a minimum so that an acceptable level of protection can be provided for these areas. Emphasis will be paid on the defence in depth approach organized around prevention, management and mitigation measures. (authors)

  15. Fire protection in nuclear power plants

    International Nuclear Information System (INIS)

    Wright, H.A.

    1981-01-01

    This lecture describes briefly the chronological order of events which may arise for a very serious emergency situation in a nuclear power plant for which preparations should be made even though the situation has an extremely low probability of happening. The planning and preparedness required are expected to cope with a whole spectrum of emergency situations, from minor accidents to serious plant failures which also lead to releases of significant quantities of radioactive material beyond the site boundary. Fire protection aspects will be briefly covered, and some guidance will be provided on exercises to ensure the plans are feasible and the appropriate personnel and facilities are in a satisfactory state of preparedness. (orig./RW)

  16. Earthquake protection of nuclear power plant equipment

    Energy Technology Data Exchange (ETDEWEB)

    Nawrotzki, Peter [GERB Vibration Control Systems, Berlin (Germany)

    2010-05-15

    Power plant machinery can be dynamically decoupled from the substructure by the effective use of helical steel springs and viscous dampers. Turbine foundations, boiler feed pumps and other machine foundations benefit from this type of elastic support systems to mitigate the transmission of operational vibration. The application of these devices may also be used to protect against earthquakes and other catastrophic events, i.e. airplane crash, of particular importance in nuclear facilities. This article illustrates basic principles of elastic support systems and applications on power plant buildings in medium and high seismic areas. Spring-damper combinations with special stiffness properties are used to reduce seismic acceleration levels of turbine components and other safety or non-safety related structures. For turbine buildings, the integration of the turbine substructure into the machine building can further reduce stress levels in all structural members. (orig.)

  17. Earthquake protection of nuclear power plant equipment

    International Nuclear Information System (INIS)

    Nawrotzki, Peter

    2010-01-01

    Power plant machinery can be dynamically decoupled from the substructure by the effective use of helical steel springs and viscous dampers. Turbine foundations, boiler feed pumps and other machine foundations benefit from this type of elastic support systems to mitigate the transmission of operational vibration. The application of these devices may also be used to protect against earthquakes and other catastrophic events, i.e. airplane crash, of particular importance in nuclear facilities. This article illustrates basic principles of elastic support systems and applications on power plant buildings in medium and high seismic areas. Spring-damper combinations with special stiffness properties are used to reduce seismic acceleration levels of turbine components and other safety or non-safety related structures. For turbine buildings, the integration of the turbine substructure into the machine building can further reduce stress levels in all structural members. (orig.)

  18. Organ dose assessment of nuclear medicine practitioners using L-block shielding device for handing diagnostic radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Se Sik; Kim, Jung Hoon [Dep. of Radiological Science, College of Health Science, Catholic University of Pusan, Busan (Korea, Republic of); Cho, Yong In [Dept. of Diagnostic Radiology, Dongnam Institute of Radiological and Medical Science, Busan (Korea, Republic of)

    2017-03-15

    In the case of nuclear medicine practitioners in medical institutions, a wide range of exposure dose to individual workers can be found, depending on the type of source, the amount of radioactivity, and the use of shielding devices in handling radioactive isotopes. In this regard, this study evaluated the organ dose on practitioners as well as the dose reduction effect of the L-block shielding device in handling the diagnostic radiation source through the simulation based on the Monte Carlo method. As a result, the distribution of organ dose was found to be higher as the position of the radiation source was closer to the handling position of a practitioner, and the effective dose distribution was different according to the ICRP tissue weight. Furthermore, the dose reduction effect according to the L-block thickness tended to decrease, which showed the exponential distribution, as the shielding thickness increased. The dose reduction effect according to each radiation source showed a low shielding effect in proportion to the emitted gamma ray energy level.

  19. Trade secrets protection mode of nuclear power plant

    International Nuclear Information System (INIS)

    Zeng Bin

    2015-01-01

    The paper analyzes the legal environment in which nuclear power enterprises are stayed, and mainly discusses the business secret protection modes of China's nuclear power enterprises. It is expected to provide a revelation and help for these enterprises to protect their business secrets. Firstly, the paper briefly expounds the legal basis of business secret protection and China's legalization status in this regard. Then it mainly puts forward the business secret management framework and postulations for nuclear power enterprises, and key points in application and protection of nuclear power business secret. (author)

  20. The quality control for biological-shield heavy concrete construction of nuclear power project

    International Nuclear Information System (INIS)

    Sun Hongjun; Ma Xinchao

    2012-01-01

    The paper introduces the function and characteristics of biological protective heavy-concrete, and its main application scope and role in Fangjiashan nuclear power project. From the aspects of raw material selection, mixing ratio test, heavy concrete production, the paper discusses the main control points of heavy concrete construction process, points out the basic characteristics of heavy concrete construction, and put forward measures to prevent density non-uniformity during heavy concrete construction and to control slump during transportation. Results prove that reasonable construction process control can assure the engineering quality. (authors)

  1. Safety guide for protection in nuclear medicine laboratories

    International Nuclear Information System (INIS)

    1995-01-01

    The regulations that must be taken into account during constructing the nuclear medicine laboratories to meet the requirements of radiation protection and the specifications of equipment in the laboratory, quality control, radioactive monitoring, protective procedures, personnel qualifications are given

  2. Radiation protection organization in Guangdong Nuclear Power Station (GNPS)

    International Nuclear Information System (INIS)

    Yang Maochun

    1993-01-01

    The French way of radiation protection management has been adopted by Guangdong Nuclear Power Station (GNPS) but there are some differences. In this paper author describes radiation protection organization in GNPS, special measures having been taken and the present status

  3. Radiological respiratory protection in Angra-1 Nuclear Power Plant

    International Nuclear Information System (INIS)

    Amaral, Marcos A. do

    1996-01-01

    The present paper has the purpose to describe the actual situation of the Radiological respiratory Protection in Angra I Nuclear Power Plant, the difficulties found and the goals to achieve, in order of the radiological protection excellence. (author)

  4. Safety study of fire protection for nuclear fuel cycle facility

    International Nuclear Information System (INIS)

    2013-01-01

    Insufficiencies in the fire protection system of the nuclear reactor facilities were pointed out when the fire occurred due to the Niigata prefecture-Chuetsu-oki Earthquake in July, 2007. This prompted the revision of the fire protection safety examination guideline for nuclear reactors as well as commercial guidelines. The commercial guidelines have been endorsed by the regulatory body. Now commercial fire protection standards for nuclear facilities such as the design guideline and the management guideline for protecting fire in the Light Water Reactors (LWRs) are available, however, those to apply to the nuclear fuel cycle facilities such as mixed oxide fuel fabrication facility (MFFF) have not been established. For the improvement of fire protection system of the nuclear fuel cycle facilities, the development of a standard for the fire protection, corresponding to the commercial standard for LWRs were required. Thus, Japan Nuclear Energy Safety Organization (JNES) formulated a fire protection guidelines for nuclear fuel cycle facilities as a standard relevant to the fire protection of the nuclear fuel cycle facilities considering functions specific to the nuclear fuel cycle facilities. In formulating the guidelines, investigation has been conduced on the commercial guidelines for nuclear reactors in Japan and the standards relevant to the fire protection of nuclear facilities in USA and other countries as well as non-nuclear industrial fire protection standards. The guideline consists of two parts; Equipments and Management, as the commercial guidances of the nuclear reactor. In addition, the acquisition of fire evaluation data for a components (an electric cabinet, cable, oil etc.) targeted for spread of fire and the evaluation model of fire source were continued for the fire hazard analysis (FHA). (author)

  5. Vehicle bomb protection for nuclear power plants

    International Nuclear Information System (INIS)

    James, J.W.; Veatch, J.D.; Goldman, L.; Massa, R.

    1989-01-01

    The six-step methodology presented in this paper can be applied to nuclear power reactors to provide protection measures and considerations against vehicle bomb threats. The methodology provides a structured framework for examining the potential vulnerability of a plant to a postulated vehicle bomb and for developing contingency planning strategies for dealing with such a possibility. The six steps are as follows: (1) identify system options available to establish and maintain a safe reactor shutdown; (2) identify buildings or other structures containing critical components and equipment associated with each system option; (3) determine survival envelopes for the system options; (4) review site features to determine vehicle access approach paths and distances as they relate to the survival envelopes; (5) identify measures to limit or thwart vehicle access, and protect and preserve preferred system options; (6) prepare contingency plans and make advance arrangements for implementation of contingency measures for a vehicle bomb attack. Portions of this methodology related to blast effects from vehicle bombs on power reactor components are implemented using BombCAD, a proprietary computer-aided design (CAD)-based blast effects analysis technique

  6. Calculation of binary magnetic properties and potential energy curve in xenon dimer: second virial coefficient of (129)Xe nuclear shielding.

    Science.gov (United States)

    Hanni, Matti; Lantto, Perttu; Runeberg, Nino; Jokisaari, Jukka; Vaara, Juha

    2004-09-22

    Quantum chemical calculations of the nuclear shielding tensor, the nuclear quadrupole coupling tensor, and the spin-rotation tensor are reported for the Xe dimer using ab initio quantum chemical methods. The binary chemical shift delta, the anisotropy of the shielding tensor Delta sigma, the nuclear quadrupole coupling tensor component along the internuclear axis chi( parallel ), and the spin-rotation constant C( perpendicular ) are presented as a function of internuclear distance. The basis set superposition error is approximately corrected for by using the counterpoise correction (CP) method. Electron correlation effects are systematically studied via the Hartree-Fock, complete active space self-consistent field, second-order Møller-Plesset many-body perturbation, and coupled-cluster singles and doubles (CCSD) theories, the last one without and with noniterative triples, at the nonrelativistic all-electron level. We also report a high-quality theoretical interatomic potential for the Xe dimer, gained using the relativistic effective potential/core polarization potential scheme. These calculations used valence basis set of cc-pVQZ quality supplemented with a set of midbond functions. The second virial coefficient of Xe nuclear shielding, which is probably the experimentally best-characterized intermolecular interaction effect in nuclear magnetic resonance spectroscopy, is computed as a function of temperature, and compared to experiment and earlier theoretical results. The best results for the second virial coefficient, obtained using the CCSD(CP) binary chemical shift curve and either our best theoretical potential or the empirical potentials from the literature, are in good agreement with experiment. Zero-point vibrational corrections of delta, Delta sigma, chi (parallel), and C (perpendicular) in the nu=0, J=0 rovibrational ground state of the xenon dimer are also reported.

  7. Handbook of radiation shielding data

    International Nuclear Information System (INIS)

    Courtney, J.C.

    1976-07-01

    This handbook is a compilation of data on units, conversion factors, geometric considerations, sources of radiation, and the attenuation of photons, neutrons, and charged particles. It also includes related topics in health physics. Data are presented in tabular and graphical form with sufficient narrative for a least first-approximation solutions to a variety of problems in nuclear radiation protection. Members of the radiation shielding community contributed the information in this document from unclassified and uncopyrighted sources, as referenced

  8. Neutron and Gamma Shielding Evaluation for KN-12 Spent Nuclear Fuel Transport Cask

    Energy Technology Data Exchange (ETDEWEB)

    Cho, I. J.; Min, D. K.; Lee, J. C.; You, G. S.; Yoon, J. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Chang, G. H.; Jeong, Y. C.; Ko, Y. W. [Korea Hydro and Nuclear Power Co., LTD., Kori (Korea, Republic of)

    2007-07-01

    The CASTOR KN-12 is designed to transport 12 intact PWR spent fuel assemblies for dry and wet transportation conditions. The overall cask length is 480.1 cm with a wall thickness 37.5 cm. Shield for the KN-12 is maintained by the thick walled cask body and the lid. For neutron shielding, polyethylene rods (PE) are arranged in longitudinal boreholes in the vessel wall and PE-plates are inserted between the cask lid and lid side shock absorber and between the cask bottom and bottom steel plate. The shielding evaluation of the cask has been performed with MCNP to confirm the shielding integrity of cask for pre-service inspection of transport cask.

  9. Civilian protection and Britain's commercial nuclear installations

    International Nuclear Information System (INIS)

    1981-01-01

    The subject is treated as follows: initial conclusions (major nuclear attack on military installations; nuclear attack including civil nuclear targets; conventional attack on civil nuclear installations); nature of nuclear weapons explosions and power reactor releases (general; dose effects and biologically significant isotopes; nuclear weapon effects; effect of reactors and other fuel-cycle installations in a thermonuclear area; implications of reactor releases due to conventional attack, sabotage, civil disorder or major accident). (U.K.)

  10. Safety catching device for pipes in missile shielding cylinders of nuclear power plants

    International Nuclear Information System (INIS)

    Hering, S.; Doll, B.

    1976-01-01

    The safety catching device consists of a steel wire passed in U-shape around the pipe to be caught and supported by two anchor ties embedded in the concrete of the missile shielding cylinder. This flexible catching device is to cause the energy released in case of a pipe rupture to be absorbed and no dangerous bending shesses to be transferred to the walls of the missile shielding cylinder. (UWI) [de

  11. Evaluation of radiation protection in nuclear medicine diagnostic procedures

    International Nuclear Information System (INIS)

    Mohammed, Ezzeldien Mohammed Nour

    2013-05-01

    This study conducted to evaluate the radiation protection in nuclear medicine diagnostic procedures in four nuclear medicine departments in Sudan. The evaluated procedures followed in these departments were in accordance with the standards, International Recommendations and code of practice for radiation protection in nuclear medicine. The evolution included the optimum design for diagnostic nuclear medicine departments, dealing with radioactive sources, quality assurance and quality control, training and responsibilities for radiation worker taking into account economic factors in Sudan. Evaluation of radiation protection procedures in diagnostic investigations was carried out by taken direct measurements of dose rate and the contamination level in some areas where radiation sources, radiation workers and public are involved. Designated questionnaires covered thirteen areas of radiation protection based on inspection check list for nuclear medicine prepared by the International Atomic Energy Agency (IAEA) and American Association of Physicist in Medicine (AAPM) were used in the evaluation. This questionnaire has been Filled by Radiation Protection Officer (RPO), nuclear medicine technologist, nuclear medicine specialist in the nuclear medicine departments. Four hospitals, two governmental hospital and two private hospitals, have been assisted, the assessment shows that although the diagnostic nuclear medicine department in Sudan are not applying a fully safety and radiation protection procedures, but the level of radiation dose and the contamination level were found within acceptable limits. The private hospital D scored the higher level of protection (85.25%) while the governmental hospital C scored the lower level of protection (59.02%). Finally, this study stated some recommendations that if implemented could improve the level of radiation protection in nuclear medicine department. One of the most important recommendations is that a proper radiation protection

  12. Code of practice of radiation protection in fixed nuclear gauges

    International Nuclear Information System (INIS)

    Eltayeb, M. A. M.

    2012-09-01

    The present work aims at developing and updating a code of practice of radiation protection in fixed nuclear gauges that comply with current international recommendations. The work also intended to evaluate the current radiation protection situation in two selected companies using nuclear gauges in Sudan. A draft of the code is proposed which includes the basic principle of protection such as source construction and gauges radiation monitoring, storage maintenance and leak testing as well as specific issues related to nuclear gauges. The practical part of this study included investigation of radiation protection in the comparisons using nuclear gauges for level detection, to evaluate the level of radiation protection and the compliance to the regulatory authority regulations. The result revealed that the two companies do not have an effective radiation protection program and that can lead to exposure of workers to unnecessary doses. Some recommendations were stated, if implemented they could improve the status of radiation protection in those companies. (Author)

  13. An innovative method for on-power radiometry of end-shields of nuclear power plants

    International Nuclear Information System (INIS)

    Kumar, Gaurav; Gupta, Pankaj; Nawal, Shriram; Gautam, Mahesh; Kakkar, Aman Deep; Yadav, Umed

    2012-01-01

    Every lndian PHWR reactor calandria is sandwiched within a pair of shield on either side. These shields are perpendicular to the coaxial axis of calandria and are called end-shields. These provide shielding from leakage radiation from reactor core in escaping out to Fuelling Machine vault, thereby significantly reducing the dose rates in the vaults. This has got a direct impact on radiation field in accessible areas. By maintaining low dose rates in accessible areas, the individual and collective doses of radiation workers can be effectively controlled well within the stipulated limits. Thus, it is of utmost importance to ensure adequacy of shielding provided by end-shields. In this context, a limited radiometry exercise is executed after filling of end-shields with steel balls and prior to their installation at designated place. This exercise provides limited inputs along the periphery of end-shield due to limited strength of radiation source, its handling provisions and dose constraints to the individual. In order to ascertain an in-depth analysis of shielding adequacy on-power, different methodologies have been adopted and have certain limitation in precisely pinpointing the affected area/location besides limitation on number of locations that can be monitored at a single stretch. To overcome these important anomalies, a computer based setup has been indigenously designed. The setup essentially comprises of a radiation monitor with wide energy, measuring, temperature and humidity range; a custom designed 25 m long compatible cable with suitable connectors; a laptop with additional cooling arrangement; a configurable interfacing software; thermal shielding for the detector and tying/fixing provisions. The radiation monitor after being properly shielded for thermal impacts is installed on the head of Fuelling Machine. It is connected through long cable to a laptop kept at Fuelling Machine service area with due cooling provisions (as temperature in the area will

  14. Pilot tests for dismantling by blasting of the biological shield of a shut down nuclear power station

    International Nuclear Information System (INIS)

    Freund, H.U.

    1995-01-01

    Following free-field tests on concrete blocks the feasibility of explosive dismantling of the biological shield of nuclear power stations has been succesfully tested at the former hotsteam reaction in Karlstein/Main Germany. For this purpose a model shield of scale 1:2 was embedded into the reactor structure at which bore-hole blasting tests employing up to about 15 kg of explosive were performed. An elaborate measurement system allowed to receive detailed information on the blast side-effects: Special emphasis was focussed on the quantitative registration of the dynamic blast loads; data for the transfer of the dismantling method to the removal of real ractor structures were obtained. (orig.) [de

  15. Onboard cross-calibration of the Pille-ISS Detector System and measurement of radiation shielding effect of the water filled protective curtain in the ISS crew cabin

    International Nuclear Information System (INIS)

    Szántó, P.; Apáthy, I.; Deme, S.; Hirn, A.; Nikolaev, I.V.; Pázmándi, T.; Shurshakov, V.A.; Tolochek, R.V.; Yarmanova, E.N.

    2015-01-01

    As a preparation for long duration space missions it is important to determine and minimize the impact of space radiation on human health. One of the methods to diminish the radiation burden is using an additional local shielding in the places where the crewmembers can stay for longer time. To increase the crew cabin shielding a special protective curtain was designed and delivered to ISS in 2010 containing four layers of hygienic wipes and towels providing an additional shielding thickness of about 8 g/cm"2 water-equivalent matter. The radiation shielding effect of the protective curtain, in terms of absorbed dose, was measured with the thermoluminescent Pille-ISS Detector System. In order to verify the reliability of the Pille system an onboard cross-calibration was also performed. The measurement proved that potentially 25% reduction of the absorbed dose rate in the crew cabin can be achieved, that results in 8% (∼16 μGy/day) decrease of the total absorbed dose to the crew, assuming that they spend 8 h in the crew cabin a day. - Highlights: • The dose level in the ISS Zvezda crew quarters is higher than the average dose level in the module. • A shielding made of hygienic wipes and towels was set up onboard as additional protection. • Onboard cross calibration of the Pille-ISS space dosimeter (TL) system was performed. • The shielding effect of the protective curtain in terms of absorbed dose was measured with the onboard Pille system. • The shielding effect of the protective water curtain is approximately 24 ± 9% in absorbed dose.

  16. Radiation and Environmental Protection Programme for the First Upcoming Nuclear Power Plant in Indonesia

    International Nuclear Information System (INIS)

    Syahrir

    2007-01-01

    Indonesia plans to operate the first nuclear power plant (NPP) by 2016. A radiation and environmental protection arrangement for NPPs is part of the whole safety system which is embedded in every practice involved radiation exposure to workers and members of public. A radiation and environmental protection programme for the NPP should adhere to international standards and mainstream in order to be acceptable to the public and international communities. International Atomic Energy Agency (IAEA) has recommended a radiation protection standard for NPPs as studied in this paper. Focus is given to the operational aspects of radiation protection program and discharge control to the environment. Some documents related to Safety Analysis Reports were used as working examples on its implementation. The study includes the classification of working areas and access control; local rules and supervision of work; work planning and work permits; protective clothing and protective equipment; facilities, shielding and equipment; application of the principle of optimization of protection; and removal or reduction in intensity of sources of radiation. The radiological protection aspects blend together in the whole NPP practices, each individual has his/her own responsibility in association with the radiation protection program implementation. It also present in the whole steps of NPP preparation up to its decommissioning. Promise on safety improvement and significant dose reduction in the recent development in NPP technology should scrutinized so that the option of proven technology as required in commercial power reactor licensing considers this tendency. (author)

  17. Hessen: ordinance concerning competences in the field of nuclear protection and radiation protection

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Competences for: 1) Licensing of nuclear facilities; 2) use of nuclear fuels; 3) plan approval procedure; 4) supervisory authorities; 5) Radiation Protection Ordinance; 6) X-Ray Ordinance; 7) proceedings and disciplinary action against breaches of the rules. (HP) [de

  18. Pakistan nuclear safety and radiation protection regulation 1990

    International Nuclear Information System (INIS)

    1990-01-01

    In this act regulations of nuclear safety and radiation protection in Pakistan has been explained. A legal and licensing procedure to handle protection of nuclear materials, processing storage of radioactive products has been described under this regulation. In these regulations full explanation of accidental exposure, delegation of powers and record keeping/waste disposal of radioactive has been given. (A.B.)

  19. Emergency protection and nuclear power station remote monitoring

    International Nuclear Information System (INIS)

    Nowak, K.; Wolf, H.

    1986-01-01

    The States of the Federal Republic of Germany are planning emergency protection measures for the environment of nuclear power stations based on their statutory duty of care. In this connection the paper explains to what extent remote monitoring of nuclear power stations practised by the Federal Supervisory Authorities may support the design and implementation of emergency protection measures. (orig.) [de

  20. Attenuation characteristics of materials used in radiation protection as radiation shielding

    International Nuclear Information System (INIS)

    Almeida Junior, Airton T.; Araujo, F.G.S.; Nogueira, M.S.; Santos, M.A.P.

    2013-01-01

    Crystal glass has been widely used as shielding material in gamma radiation sources as well as x-ray generating equipment to replace the plumbiferous glass, in order to minimize exposure to individuals. In this work, ten plates of crystal glass, with dimensions of 20cm x 20cm and range of thicknesses from 0.5 to 2.0 cm, and barite concrete were irradiated with potential constants of 60kV, 80kV, 110kV, 150kV and gamma radiation of 60 Co. The curves of attenuation and of transmission were obtained for crystal glass, barite plaster and barite concrete (mGy/mA.min) at 1 meter as a function of thickness.Crystal glass has been widely used as shielding material in gamma radiation sources as well as x-ray generating equipment to replace the plumbiferous glass, in order to minimize exposure to individuals. In this work, ten plates of crystal glass, with dimensions of 20cm x 20cm and range of thicknesses from 0.5 to 2.0 cm, and barite concrete were irradiated with potential constants of 60kV, 80kV, 110kV, 150kV and gamma radiation of 60 Co. The curves of attenuation and of transmission were obtained for crystal glass, barite plaster and barite concrete (mGy/mA.min) at 1 meter as a function of thickness. (author)

  1. Shielding benchmark problems, (2)

    International Nuclear Information System (INIS)

    Tanaka, Shun-ichi; Sasamoto, Nobuo; Oka, Yoshiaki; Shin, Kazuo; Tada, Keiko.

    1980-02-01

    Shielding benchmark problems prepared by Working Group of Assessment of Shielding Experiments in the Research Committee on Shielding Design in the Atomic Energy Society of Japan were compiled by Shielding Laboratory in Japan Atomic Energy Research Institute. Fourteen shielding benchmark problems are presented newly in addition to twenty-one problems proposed already, for evaluating the calculational algorithm and accuracy of computer codes based on discrete ordinates method and Monte Carlo method and for evaluating the nuclear data used in codes. The present benchmark problems are principally for investigating the backscattering and the streaming of neutrons and gamma rays in two- and three-dimensional configurations. (author)

  2. Particular features of fire protection in nuclear power plants

    International Nuclear Information System (INIS)

    Krueger, W.

    1985-01-01

    The particular features of fire protection in nuclear power plants that are connected with the need to ensure nuclear and radiation safety even during an emergency are outlined followed by the recommendation to lay them down in special fire protection standards. These, in conjunction with comprehensive fire hazard analyses, could serve to work out complex concepts for the fire protection of individual nuclear power plants. Such concepts would be very useful for review and assessment of the fire protection design during the licensing process and for later inspections. (author)

  3. Study on preparation of ultrafine lead tungstate for radiation protection and γ-ray shielding of the gloves

    International Nuclear Information System (INIS)

    Du Licheng; He Ping; Zhou Yuanlin; Song Kaiping; Yang Kuihua

    2012-01-01

    Lead tungstate combines the radiation shielding properties of tungsten and lead, and it is quite distinctive to manufacture lead tungstate with ultra-fine granularity to enhance its capacity of radiation shielding. The grain size of lead tungstate has direct impact on the ability of its protection from radioactive materials. the smaller the grain size and more uniform dispersion of lead tungstate, the better protective ability it is going to be. In this paper, soft-template synthesis was introduced to prepare ultra-fine PbWO 4 . Rigorous experiment conditions are settled to ensure the access to obtain ultra-fine, homogeneous lead tungstate product, and it is better than other physical and chemical preparation methods. The surface-active agent for the soft template, with S-60 for the water system W/O microemulsion zone, was used to synthesize successfully ultra-fine PbWO 4 . It was shown that dispersing agent S-60 in the soft template method produced ultra-fine PbWO 4 with uniform granularity distribution. By using orthogonal experimental method, the best experimental conditions were obtained as follows: S-60 as surfactant dispersant with diluted 30 times concentration, solutions with pH9, 0.01 mol/L concentration of reactant, 1300 rpm of stirring speed and slowly adding drops of Na 2 WO 4 solution into Pb (Ac) 2 solution. Based on the optimal experimental conditions, the product of ultra-fine product for the anti-radiation protection filler has been made. The fine packing for the preparation of tungsten the gamma rays on the gloves is an average capacity of 5% or so. (authors)

  4. Workers radiation protection. Solutions accommodate new needs. The tool box of radiation protection expands itself. Industrial radiology: workers aware of risks. To design a shielded enclosure

    International Nuclear Information System (INIS)

    Rannou, Alain; Billarand, Yann; Scanff, Pascale; Etard, Cecile; Sage, Julie; Jolivet, Patrick; Israel, Sylvain; Caplin, Helene; Couasnon, Olivier; Cordelle, Anne

    2017-01-01

    A first article proposes an overview of developments in the field of workers radiation protection. This development is notably motivated by the future dismantling works. It can be noticed that some other issues are considered as more important than radiation protection in the medical field even though radiation protection is a matter of concern for radiology manipulators. Radiation protection is also an issue for workers performing luggage X-ray controls in airports. As revealed by some measurements, artificial radioactivity should be controlled. Radiation protection is planned in relationship with an exposure scenario. The Belgium example is evoked with the development of centralised data and statistics in order to compare workers profiles. A second article comments the evolution of the activity of radiation protection with its new documents, methodologies (notably for operating rooms), and practical studies. While indicating how much the number of specialised workers increased, and how much dose control has been developed in the medical sector, and in terms of workers wearing a ring- or wrist-dosimeter between 2006 and 2015, and also indicating the distribution of controlled workers among sectors, the article outlines that a computation tool is shared between professionals, and how sheets on radionuclides are published and shared. The third article briefly addresses industrial radiology to outlines that workers are always more aware of risks. The last article briefly describes how a shielded enclosure is designed to limit workers exposure

  5. Advanced nuclear control and protection system ANCAP-80

    International Nuclear Information System (INIS)

    Asai, Takashi; Okano, Michihiko; Ishibashi, Kengo; Hasegawa, Masakoto; Fukuda, Hiroyoshi; Hosomichi, Renichi.

    1983-01-01

    Advanced reactor protection systems were developed to improve operational reliability and availability and to ease the burden of operators of Mitsubishi PWR Nuclear Power Stations. (Called ANCAP-80; Advanced Nuclear Control And Protection System) For the PWR plants now being planned and in future plans, Mitsubishi will adopt these systems with the following functional features; (1) Four channel protection logic, (2) Automatic bypass logic, (3) Automatic test provision, (4) Optical isolators. (author)

  6. Nuclear energy and radiation protection law: no. 14 1987

    International Nuclear Information System (INIS)

    1987-01-01

    The full text of Jordan's Nuclear Energy and Radiation Protection Law, no. 14 1987. The law's 39 articles govern all aspects organizing the utilization of nuclear energy and radiation protection activities in the country; including terms and conditions for licensing activities and personnel, and the import, export, and disposal of radioactive sources. The law establishes for the purpose of implementing its regulations, a consultative technical committee and a radiation protection board, both in the Ministry of Energy and Mineral Resources

  7. Respiratory and protective equipment at a large nuclear facility

    International Nuclear Information System (INIS)

    Zippler, D.B.

    1975-12-01

    A variety of personal protective equipment is used in a large nuclear facility to protect employees against both nuclear and ordinary industrial materials. Equipment requirements are based on risk evaluation and may range from a minimum of shoe covers to whole body protection by air-supplied plastic suits. Types of equipment are listed and one-year costs are given. Criteria for evaluating and compartmentalizing risks are discussed. Air-supplied suits and hoods are discussed in detail

  8. EURISOL-DS Multi‐MW Target: Radiological Protection, Radiation Safety and Shielding Aspects

    CERN Document Server

    Y. Romanets and R. Luís (ITN)

    The objective of this work was to carry out a detailed study and analysis of all aspects related toradioprotection and radiation safety of the spallation target area and the whole spaces reservedfor the fission targets and spallation target maintenance. Operational and no‐operationalconditions were considered for an evaluation of the radiation safety conditions.An analysis of the proposed shielding dimensions and configuration was performed for thesystem during operation time. Parameters as activation, dose rate, energy deposition, etc. aremore important for the no‐operation period, in order to evaluate the hazard level anddetermine the staff access type to the maintenance areas (direct or remote control).Such elements as the fission targets and the whole structure involved on it were studied in moredetail because of the disposal issues, after operation. Activation, dose rate and residual nuclideswere studied for each element of the assembly. All parameters were analyzed according to their...

  9. Implementing Physical Protection Education for an Enhanced Nuclear Security Culture

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Ho; Kim, Hyun Chul; Shin, Ick Hyun; Lee, Hyung Kyung; Choe, Kwan Kyoo [KINAC, Daejeon (Korea, Republic of)

    2013-10-15

    In this paper, we are going to outline our efforts and experiences at implementing physical protection education. KINAC (as the only designated educational institute) places great effort in delivering an effective and a high-quality education program for physical protection. We have also provided a way for nuclear operators to share the lessons they have gained through their own experiences. We made physical protection education an important communication channel, not only among nuclear operators but also between operators and a regulatory body. There is growing attention given to education and training on the subject of physical protection in order to enhance the nuclear security culture. The IAEA recommends that all personnel in organizations directly involved with the nuclear industry receive regularly education in physical protection according to the recently revised INFCIRC/225/Rev.5. The Korea Institute of Nuclear Nonproliferation and Control (KINAC) and the Nuclear Safety and Security Commission (NSSC), which are mainly responsible for the national nuclear security regime, have already recognized the importance of education and training in physical protection. The NSSC enacted its decree on physical protection education and training in 2010. KINAC was designated as the first educational institute in 2011 and implemented physical protection education as mandatory from 2012.

  10. Implementing Physical Protection Education for an Enhanced Nuclear Security Culture

    International Nuclear Information System (INIS)

    Lee, Jeong Ho; Kim, Hyun Chul; Shin, Ick Hyun; Lee, Hyung Kyung; Choe, Kwan Kyoo

    2013-01-01

    In this paper, we are going to outline our efforts and experiences at implementing physical protection education. KINAC (as the only designated educational institute) places great effort in delivering an effective and a high-quality education program for physical protection. We have also provided a way for nuclear operators to share the lessons they have gained through their own experiences. We made physical protection education an important communication channel, not only among nuclear operators but also between operators and a regulatory body. There is growing attention given to education and training on the subject of physical protection in order to enhance the nuclear security culture. The IAEA recommends that all personnel in organizations directly involved with the nuclear industry receive regularly education in physical protection according to the recently revised INFCIRC/225/Rev.5. The Korea Institute of Nuclear Nonproliferation and Control (KINAC) and the Nuclear Safety and Security Commission (NSSC), which are mainly responsible for the national nuclear security regime, have already recognized the importance of education and training in physical protection. The NSSC enacted its decree on physical protection education and training in 2010. KINAC was designated as the first educational institute in 2011 and implemented physical protection education as mandatory from 2012

  11. Shielding requirements for particle bed propulsion systems

    Science.gov (United States)

    Gruneisen, S. J.

    1991-06-01

    Nuclear Thermal Propulsion systems present unique challenges in reliability and safety. Due to the radiation incident upon all components of the propulsion system, shielding must be used to keep nuclear heating in the materials within limits; in addition, electronic control systems must be protected. This report analyzes the nuclear heating due to the radiation and the shielding required to meet the established criteria while also minimizing the shield mass. Heating rates were determined in a 2000 MWt Particle Bed Reactor (PBR) system for all materials in the interstage region, between the reactor vessel and the propellant tank, with special emphasis on meeting the silicon dose criteria. Using a Lithium Hydride/Tungsten shield, the optimum shield design was found to be: 50 cm LiH/2 cm W on the axial reflector in the reactor vessel and 50 cm LiH/2 cm W in a collar extension of the inside shield outside of the pressure vessel. Within these parameters, the radiation doses in all of the components in the interstage and lower tank regions would be within acceptable limits for mission requirements.

  12. Organization of radiation protection in German nuclear power stations

    International Nuclear Information System (INIS)

    1989-01-01

    Using the operating handbooks of the nuclear power stations in West Germany, an examination was carried out of how far the existing organisational structure for radiation protection fulfils the requirements for protection and whether a standardisation of the organisation would provide improvements for the protection of the personnel and for the practicability of the radiation protection organisation. In particular, the parts 'Personnel operating organisation', 'Radiation protection order' and 'Maintenance order' of the operating handbook were evaluated and an audit was made of the radiation protection organisation. In general, the result of the assessment is that the organisation of radiation protection does not contradict the orders, guidelines and regulations in any of the nuclear power stations examined. Corresponding to the possibilities of regulating details of the radiation protection organisation within the undertaking, the target of 'protection of the personnel against radioactive irradiation' is achieved by the various organisation structures which are largely equal to the given example. (orig./HP) [de

  13. Safety catching device for pipe lines in missile shielding cylinders of nuclear power plants

    International Nuclear Information System (INIS)

    Hering, S.; Doll, B.

    1975-01-01

    The safety catching device for pipes in the missile shielding cylinders consists of a flexible steel cable surrounding the pipe in a distance in U-shape. The arrester cable - which works as a spring and is freely movable in all directions - is attached to the cylinder wall. For this, the ends of the cable are primarily fastened to anchor boxes which are then inserted in a stay tube with the same axis as the cable ends. The anchor boxes are fastened to the outer wall of the missile shielding cylinder by anchor bolts and holding plates. (DG/AK) [de

  14. Nuclear safety and radiation protection in the German Democratic Republic

    International Nuclear Information System (INIS)

    Sitzlack, G.; Scheel, H.

    1976-01-01

    The radiation protection organization in the GDR is outlined laying emphasis on the tasks of the National Board of Nuclear Safety and Radiation Protection. In addition to the basic tasks, the various forms of radiation protection monitoring, the management of radioactive wastes, and international responsibilities are briefly explained. (author)

  15. Radiation protection in Swiss nuclear installations; Strahlenschutz in Schweizer Kernanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, J.; Brunell, M. [Eidgenoessisches Nuklearsicherheitsinspektorat ENSI, Brugg (Switzerland)

    2015-07-01

    Well developed measures on operational radiation protection within Swiss nuclear installations will be presented. The focus lays on competent authority actions. Results of the last ten years, including events on radiation issues, will be discussed. Finally a view on challenges for radiation protection personnel with respect to a renewed Swiss radiation protection legislation based on recent ICRP recommendations will be given.

  16. Theoretical Study of H/D Isotope Effects on Nuclear Magnetic Shieldings Using an ab initio Multi-Component Molecular Orbital Method

    Directory of Open Access Journals (Sweden)

    Masanori Tachikawa

    2013-05-01

    Full Text Available We have theoretically analyzed the nuclear quantum effect on the nuclear magnetic shieldings for the intramolecular hydrogen-bonded systems of σ-hydroxy acyl aromatic species using the gauge-including atomic orbital technique combined with our multi-component density functional theory. The effect of H/D quantum nature for geometry and nuclear magnetic shielding changes are analyzed. Our study clearly demonstrated that the geometrical changes of hydrogen-bonds induced by H/D isotope effect (called geometrical isotope effect: GIE is the dominant factor of deuterium isotope effect on 13C chemical shift.

  17. Physical protection and its role in nuclear non-proliferation

    International Nuclear Information System (INIS)

    Nilsson, A.

    1999-01-01

    Non-proliferation of nuclear weapons has been one of the main concerns of the international community since the first nuclear weapons were developed. To prevent the proliferation of nuclear weapons has been on the agenda for individual States, groups of States and the international organizations. A number of treaties, conventions and agreements, the most important being the Non-Proliferation Treaty, have been negotiated to prevent the horizontal proliferation of nuclear weapons. States have concluded safeguards agreements with the IAEA to fulfill their obligations according to Article III.1 of the NPT. Other agreements relate to the prevention of vertical proliferation and also to the disarmament of nuclear weapons. It has also been recognized that sub-national, terrorist, or criminal activities may pose a proliferation risk. Illicit trafficking of nuclear material, particularly highly enriched uranium or plutonium, is a non-proliferation concern. States have recognized the need to prevent, as far as possible, the use of nuclear material in unlawful activities. The Convention of Physical Protection of Nuclear Materials, obligates the State Parties to protect nuclear material from theft during international transport, and to make unlawful possession, use, etc., of nuclear material a criminal offense, subject to punishment under national law. Although the physical protection convention recognizes the importance of the physical protection of nuclear material in domestic use, storage and transport, it does not obligate the State party to establish the necessary systems for this purpose. It is this limitation which led many States to believe that the international physical protection regime needs to be strengthened. Although not legally binding per se, the recommendations documented in INFCIRC/225/Rev. 4, The Physical Protection of Nuclear Material and Nuclear Facilities, has obtained wide recognition. There is recognition among States that protecting nuclear material

  18. Nuclear Magnetic Shielding of Monoboranes: Calculation and Assessment of B-11 NMR Chemical Shifts in Planar BX3 and in Tetrahedral [BX4](-) Systems

    Czech Academy of Sciences Publication Activity Database

    Macháček, Jan; Bühl, M.; Fanfrlík, Jindřich; Hnyk, Drahomír

    2017-01-01

    Roč. 121, č. 50 (2017), s. 9631-9637 ISSN 1089-5639 R&D Projects: GA ČR(CZ) GA17-08045S Institutional support: RVO:61388980 ; RVO:61388963 Keywords : Electrostatic potentials * Nonrelativistic * Nuclear magnetic shieldings Subject RIV: CA - Inorganic Chemistry OBOR OECD: Inorganic and nuclear chemistry Impact factor: 2.847, year: 2016

  19. Nuclear safety and radiation protection surveillance in different countries. Switzerland

    International Nuclear Information System (INIS)

    1993-01-01

    The information and historical review on the Nuclear Surveillance in Switzerland has been presented. Special attention has been paid on: general tasks and responsibility of the Nuclear Surveillance, its organization structures, legal aspects, regulations and recommendations governing all nuclear activities in Switzerland, licensing processes and their procedures, inspections and control functions as well as international cooperation in the field of nuclear safety and environment protection

  20. Regulatory Guidance for Lightning Protection in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kisner, Roger A.; Wilgen, John B.; Ewing, Paul D.; Korsah, Kofi; Antonescu, Christina E.

    2006-01-01

    Oak Ridge National Laboratory (ORNL) was engaged by the U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research (RES) to develop the technical basis for regulatory guidance to address design and implementation practices for lightning protection systems in nuclear power plants (NPPs). Lightning protection is becoming increasingly important with the advent of digital and low-voltage analog systems in NPPs. These systems have the potential to be more vulnerable than older analog systems to the resulting power surges and electromagnetic interference (EMI) when lightning strikes facilities or power lines. This paper discusses the technical basis for guidance to licensees and applicants covered in Regulatory Guide (RG) 1.204, Guidelines for Lightning Protection of Nuclear Power Plants, issued August 2005. RG 1.204 describes guidance for practices that are acceptable to the NRC staff for protecting nuclear power structures and systems from direct lightning strikes and the resulting secondary effects.

  1. Present and future problems of radiation shielding for maritime transport of nuclear spent fuels

    International Nuclear Information System (INIS)

    Ueki, K.; Nariyama, N.; Ohashi, A.

    2000-01-01

    The transport of spent fuels with casks began in September 1999 by the exclusive spent fuel transport vessel the 'Rokuei Maru'. The casks have been transported to the reprocessing plant at Rokkasho-village in Aomori Prefecture. The 'Rokuei Maru' is approximately 100 m-length, 16.5 m-width and 3,000 gross-tons. The 20 NFT casks can be loaded into 5 holds. At the present time, the NFT casks can carry spent fuels of up to 44,000 MWD/MTU. Serpentine concrete is employed as a neutron shields in the hatch covers, the bulkheads, and the house front of the accommodations except the wheelhouse. Polyethylene covers the side walls in each hold. The neutron shielding ability of serpentine concrete and polyethylene was investigated by a shielding experiment using a 252 Cf-neutron source. The shielding experiment was analyzed with the Monte Carlo code MCNP 4B. In the near future, on-board experiment will be carried out to measure the dose-equivalent rate distributions in the 'Rokuei Maru' and the measured data and the Monte Carlo analysis of it will establish the radiation safety of the ship. (author)

  2. Onboard radiation shielding estimates for interplanetary manned missions

    International Nuclear Information System (INIS)

    Totemeier, A.; Jevremovic, T.; Hounshel, D.

    2004-01-01

    The main focus of space related shielding design is to protect operating systems, personnel and key structural components from outer space and onboard radiation. This paper summarizes the feasibility of a lightweight neutron radiation shield design for a nuclear powered, manned space vehicle. The Monte Carlo code MCNP5 is used to determine radiation transport characteristics of the different materials and find the optimized shield configuration. A phantom torso encased in air is used to determine a dose rate for a crew member on the ship. Calculation results indicate that onboard shield against neutron radiation coming from nuclear engine can be achieved with very little addition of weight to the space vehicle. The selection of materials and neutron transport analysis as presented in this paper are useful starting data to design shield against neutrons generated when high-energy particles from outer space interact with matter on the space vehicle. (authors)

  3. High Hydrogen Thoraeus Rubber Gossamer Radiation Shielding for Human Protection, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic has recently developed ultra-lightweight, durable, high hydrogen containing Thoraeus Rubber™ nanocomposites that may serve as radiation protection for...

  4. Nuclear Security Recommendations on Physical Protection of Nuclear Material and Nuclear Facilities (INFCIRC/225/Revision 5): Recommendations

    International Nuclear Information System (INIS)

    2011-01-01

    This publication, Revision 5 of Physical Protection of Nuclear Material and Nuclear Facilities (INFCIRC/225), is intended to provide guidance to States and their competent authorities on how to develop or enhance, implement and maintain a physical protection regime for nuclear material and nuclear facilities, through the establishment or improvement of their capabilities to implement legislative and regulatory programmes. The recommendations presented in this publication reflect a broad consensus among IAEA Member States on the requirements which should be met for the physical protection of nuclear materials and nuclear facilities.

  5. Accelerator shielding benchmark problems

    International Nuclear Information System (INIS)

    Hirayama, H.; Ban, S.; Nakamura, T.

    1993-01-01

    Accelerator shielding benchmark problems prepared by Working Group of Accelerator Shielding in the Research Committee on Radiation Behavior in the Atomic Energy Society of Japan were compiled by Radiation Safety Control Center of National Laboratory for High Energy Physics. Twenty-five accelerator shielding benchmark problems are presented for evaluating the calculational algorithm, the accuracy of computer codes and the nuclear data used in codes. (author)

  6. Nuclear power plants - active environment protection|

    International Nuclear Information System (INIS)

    Aegerter, I.

    1987-01-01

    The Federal Commission, which is studying energy scenarios, will doubtlessly come to the conclusion that a withdrawal from nuclear energy is technically and economically feasible. Feasibility alone however is no justification for action. Have the questions been asked correctly by the parliamentarians? Are the real problems being bypassed? Is the demand for a withdrawal from nuclear energy soundly based? Is it not oversimplified? Many people are afraid of nuclear energy because they do not understand it. It is necessary that specialists formulate their ideas so that the layman can easily understand them. The broad public can be educated to lose their fear of nuclear power plants which they compare with the nuclear bombs. They can also be educated to lose their fear of radioactivity. The public should also realize that the CO 2 problem is actual and very serious, and that nuclear energy can in fact help to alleviate this particular problem. 7 refs., 2 figs., 1 tab

  7. Protective clothing use at the Savannah River Plant Nuclear Facility

    International Nuclear Information System (INIS)

    Cabbil, C.C.

    1987-01-01

    The mission of the Savannah River Plant in producing nuclear materials does pose some unique protective clothing and equipment requirements not usually seen in the general industry. In addition to protection from the chemicals and physical agents encountered, radioactive hazards must also be managed. This paper describes the protective clothing and respiratory protection used at SRP, and focuses particularly on the development of a new plastic suit. 5 refs., 7 figs., 3 tabs

  8. Radiation protection databases of nuclear safety regulatory authority

    International Nuclear Information System (INIS)

    Janzekovic, H.; Vokal, B.; Krizman, M.

    2003-01-01

    Radiation protection and nuclear safety of nuclear installations have a common objective, protection against ionising radiation. The operational safety of a nuclear power plant is evaluated using performance indicators as for instance collective radiation exposure, unit capability factor, unplanned capability loss factor, etc. As stated by WANO (World Association of Nuclear Operators) the performance indicators are 'a management tool so each operator can monitor its own performance and progress, set challenging goals for improvement and consistently compare performance with that of other plants or industry'. In order to make the analysis of the performance indicators feasible to an operator as well as to regulatory authorities a suitable database should be created based on the data related to a facility or facilities. Moreover, the international bodies found out that the comparison of radiation protection in nuclear facilities in different countries could be feasible only if the databases with well defined parameters are established. The article will briefly describe the development of international databases regarding radiation protection related to nuclear facilities. The issues related to the possible development of the efficient radiation protection control of a nuclear facility based on experience of the Slovenian Nuclear Safety Administration will be presented. (author)

  9. Wood metal. A material of interest for the preparation of individual collimators and radiation protective means

    International Nuclear Information System (INIS)

    Schumann, E.; Keiner, P.; Klose, E.

    1978-01-01

    On the grounds of its physical properties Wood metal is suitable for the preparation of individual collimators, shields and other radiation protective means in clinical radiology. Advantages and disadvantages of these self-made protective means are discussed. Its use for constructing special shielding elements and filters applied in radiotherapy as well as for shielding syringes applied in nuclear medicine is demonstrated. (author)

  10. Course in fire protection training for nuclear power plant personnel

    International Nuclear Information System (INIS)

    Walker, K.L.; Bates, E.F.; Randall, J.D.

    1979-01-01

    Proposed Regulatory Guide 1.120, entitled ''Fire Protection Guidelines for Nuclear Power Plants,'' provides detailed requirements for the overall fire protection programs at nuclear power plant sites in the United States. An essential element in such a program in the training of plant fire brigade personnel is the use of proper firefighting techniques and equipment. The Texas A and M University Nuclear Science Center (NSC) in conjunction with the Fire Protection Training Division of the Texas Engineering Extension Service has developed a one-week course to meet this training need. The program emphasizes hands-on exercises. The course is designed for up to 18 students with all protective clothing provided. Fire instructors are certified by the State of Texas, and registered nuclear engineers and certified health physicists supervise the radiological safety exercises. The first course was conducted during the week of January 8--12, 1979

  11. Requirements of radiation protection and safety for nuclear medicine services

    International Nuclear Information System (INIS)

    1989-01-01

    The requirements of radiation protection and safety for nuclear medicine services are established. The norms is applied to activities related to the radiopharmaceuticals for therapeutics and 'in vivo' diagnostics purposes. (M.C.K.) [pt

  12. Convention on the Physical Protection of Nuclear Material

    International Nuclear Information System (INIS)

    1980-01-01

    The convention on the Physical Protection of Nuclear Material is composed of the text of 23 articles, annex 1 showing the levels of physical protection and annex 2 which is the categorization list of nuclear material. The text consists of definitions (article 1), the scope of applications (2), liability of protecting nuclear material during international transport (3 and 4), duty of mutual cooperation (5 and 6), responsibility for criminal punishment (7 to 13), and final provisions (14 to 23). It is to be noted that the nuclear material for military purposes and domestic nuclear facilities are excluded in the connection. After the brief description of the course leading to the establishment of the convention, individual articles and annexes and the respective Japanese version, and the explanation based on the intergovernmental meeting discussion on the draft convention are described. (J.P.N.)

  13. Gauge origin independent calculations of nuclear magnetic shieldings in relativistic four-component theory

    DEFF Research Database (Denmark)

    Ilias, Miroslav; Saue, Trond; Enevoldsen, Thomas

    2009-01-01

    The use of perturbation-dependent London atomic orbitals, also called gauge including atomic orbitals, has proven efficient for calculations of NMR shielding constants and other magnetic properties in the nonrelativistic framework. In this paper, the theory of London atomic orbitals for NMR...... calculates the diamagnetic contribution as an expectation value, leads to significant errors and is not recommended. (C) 2009 American Institute of Physics. [doi:10.1063/1.3240198]...

  14. Aspects of radiological protection in nuclear installations

    International Nuclear Information System (INIS)

    Hunt, J.G.; Oliveira Filho, D.S.; Rabello, P.N.P.

    1987-01-01

    Due to the short term, long term and genetic effects of radiation, the work with radioactive materials requires special protection measures. The objective of radiological protection is to assure the occupational health of the workers by maintaining the dose levels as low as reasonably achievable. The radiological protection measures implanted in the NUCLEBRAS fuel element factory are described. The philosophy and practical measures taken are explained, and a comparison between radiation protection and industrial safety norms is made. The result of this work shows that the radiological safety of the element factory is assured. (author) [pt

  15. Shielding properties of protective thin film coatings and blended concrete compositions for high level waste storage packages

    International Nuclear Information System (INIS)

    Fusco, Michael A.; Winfrey, Leigh; Bourham, Mohamed A.

    2016-01-01

    Highlights: • Measured linear attenuation coefficients are the same for bare and coated steels. • Gamma mean free path is much larger than coating thickness; buildup is negligible. • ‘Concrete-6’ reduces exposure rate outside spent fuel cask significantly over ordinary concrete. - Abstract: Various thin film coatings have been proposed to protect stainless steel high level waste (HLW) containers from premature failure due to localized corrosion, hydrogen embrittlement, and mechanical wear. These coatings include TiN, ZrO 2 , MoS 2 , TiO 2 , and Al 2 O 3 , to be deposited either in multiple layers or as a thicker, single-layer composite. Linear attenuation coefficients of these materials have been simulated using MicroShield and measured experimentally for various photon energies. Additionally, spent fuel casks with overpacks made of two different types of concrete were simulated to compare exposure rate at the cask surface. In the energy range that is significant for high level waste storage all coating materials possess very similar attenuation behavior. A specialty concrete, containing magnetite (Fe 3 O 4 ) and lead oxide (PbO), reduces the exposure rate at the outer surface of the overpack by several orders of magnitude. The higher-Z elements not present in ordinary concrete greatly increase attenuation of intermediate-energy gammas (0.4–1.0 MeV). The thin film coatings do not affect the shielding capabilities of the HLW packaging, as their total proposed thickness is nearly three orders of magnitude less than the mean free path (MFP) of the primary photons of interest.

  16. Importance of self-shielding for improving sensitivity coefficients in light water nuclear reactors

    International Nuclear Information System (INIS)

    Foad, Basma; Takeda, Toshikazu

    2014-01-01

    Highlights: • A new method has been developed for calculating sensitivity coefficients. • This method is based on the use of infinite dilution cross-sections instead of effective cross-sections. • The change of self-shielding factor due to cross-section perturbation has been considered. • SRAC and SAINT codes are used for calculating improved sensitivities, while MCNP code has been used for verification. - Abstract: In order to perform sensitivity analyzes in light water reactors where self-shielding effect becomes important, a new method has been developed for calculating sensitivity coefficient of core characteristics relative to the infinite dilution cross-sections instead of the effective cross-sections. This method considers the change of the self-shielding factor due to cross-section perturbation for different nuclides and reactions. SRAC and SAINT codes are used to calculate the improved sensitivity; while the accuracy of the present method has been verified by MCNP code and good agreement has been found

  17. Safety study of fire protection for nuclear fuel cycle facility

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    Based on the investigation of fire protection standards for domestic and foreign nuclear facilities, the fire protection guideline for nuclear fuel cycle facility has been completed. In 2012, trial operation is started by private company using the guideline. In addition, the acquisition of fire evaluation data for a components (electric cable) targeted for spread of fire and the evaluation model of fire source were continued for the fire hazard analysis (FHA). (author)

  18. Introduction to symposium 'radiation protection at nuclear facilities'

    International Nuclear Information System (INIS)

    Stricker, L.

    1996-01-01

    An introduction to the symposium 'radiation protection of nuclear facilities' on Wednesday, April 17, 1996 in Vienna has been given. The number of operating reactors and the total collective dose per reactor in OECD countries has been discussed. The evolution of the total collective dose associated with the replacement of steam generators at nuclear power reactors from 1979 to 1995 is presented. The background and culture of radiation protection, regulatory aspects, strategic formulation, plan management policy and organization responsibilities are discussed generally. (Suda)

  19. A Regulators Systematic Approach to Physical Protection for Nuclear Facilities

    International Nuclear Information System (INIS)

    Bayer, Stephan; Doulgeris, Nicholas; Leask, Andrew

    2004-01-01

    This paper outlines the framework for a physical protection regime which needs to be incorporated into the design and construction phases of nuclear facility. The need for physical protection considerations at the outset of the design of nuclear facilities is explained. It also discusses about the consequences of malicious activity and the management of risk. Various risk and consequences evaluations are undertaken, notably using design basis threat methodology. (author)

  20. Physical protection of facilities and special nuclear materials in france

    International Nuclear Information System (INIS)

    Jeanpierre, G.

    1980-01-01

    Physical protection of nuclear facilities and special nuclear materials is subject in France to a national governmental regulation which provides for the basic principles to be taken into account and the minimal level of protection deemed necessary. But the responsibility of implementation is left to the facility management and the resulting decentralization allows for maximum efficiency. All safeguards measures comply with the commitments taken at the international level by the French government

  1. Safety study of fire protection for nuclear fuel cycle facility

    International Nuclear Information System (INIS)

    2013-01-01

    Based on the investigation of fire protection standards for domestic and foreign nuclear facilities, the fire protection guideline for nuclear fuel cycle facility has been completed. In 2012, trial operation is started by private company using the guideline. In addition, the acquisition of fire evaluation data for a components (electric cable) targeted for spread of fire and the evaluation model of fire source were continued for the fire hazard analysis (FHA). (author)

  2. Effects of neutron source ratio on nuclear characteristics of D-D fusion reactor blankets and shields

    International Nuclear Information System (INIS)

    Nakashima, Hideki; Nakao, Yasuyuki; Ohta, Masao

    1978-01-01

    An examination is made of the dependence shown by the nuclear characteristics of the blanket and shield of D-D fusion reactors on S sub( d d)/S sub( d t), the ratio between the 2.45 MeV neutrons resulting from the D-D reaction and those of 14.06 MeV from the D-T reaction. Also, an estimate is presented of this neutron source ratio S sub( d d)/S sub( d t) for the case of D-D reactors, taken as an example. It is shown that an increase of S sub( d d)/S sub( d t) reduces the amount of nuclear heating per unit source neutron, while at the same time improving the shielding characteristics. This is accountable to lowering of the energy and penetrability of incident neutrons into the blanket brought about by the increase of S sub( d d)/S sub( d t). The value of S sub( d d)/S sub( d t) in a steady state D-D fusioning plasma core is estimated to be 1.46 -- 1.72 for an ion temperature ranging from 60 -- 180 keV. The reductions obtained on H sub( t)sup( b) (total heating in the blanket), H sub( t)sup( m g)/H sub( t)sup( b) (shielding indicator = ratio between total heating in superconducting magnet and that in the blanket) and phi sup( m g)/phi sup( w) (ratio of fast neutron fluxes between that at the magnet inner surface and that at the first wall inner surface) brought about by increasing S sub( d d)/S sub( d t) from unity to the value cited above do not differ to any appreciable extent, whichever is adopted among the design models considered here, the differences being at most about 10, 15 and 25%, respectively, for these three parameters. These results would broaden the validity of the conclusion derived in the previous paper for the case of S sub( d d)/S sub( d t) = 1.0, that the blanket-shield concept would appear to be the most suitable for D-D fusion reactors. (author)

  3. Pakistan nuclear safety and radiation protection ordinance-1984

    International Nuclear Information System (INIS)

    1984-01-01

    An act to provide the regulations of nuclear safety and radiation protection in Pakistan has been explained. A legal and licensing procedure to handle production of nuclear materials, processing, storage of radioactive products and wastes has been described under this regulation. (A.B.)

  4. Analysis of fire protection in nuclear power plants

    International Nuclear Information System (INIS)

    Hosser, D.; Schneider, U.

    1982-01-01

    Regulations and test specifications for fire prevention in nuclear power plants are presented as well as the fire protection measures in a newly constructed nuclear power plant. Although the emphasis is placed differently, all rules are based on the following single measures: Fire prevention, fire detection, fire fighting, fire checking, attack, flight, and rescue, organisational measures. (orig./GL) [de

  5. Protect the environment with nuclear power

    International Nuclear Information System (INIS)

    Kemm, K.R.

    1979-01-01

    In this article the author discusses nuclear power in comparison with alternative energy sources, by referring to the problem of pollution, safety records and prices. He then comes to the conclusion that we are fortunate in having nuclear power to assist in meeting the problems of energy supply for mankind which loom ahead. We should therefore endeavour to emphasise the positive nature of this alternative

  6. Fire protection in the nuclear power plant

    International Nuclear Information System (INIS)

    Takuma, Masao

    1977-01-01

    According to the publication by US NRC, 32 fires have occurred in the nuclear power stations in operation, but most of them were small fire, and did not affect the safety of the nuclear power stations. The largest fire was that which occurred in the Browns Ferry Nuclear Power Station of TVA, USA, in March, 1976. It did not jeopardize the safety of the reactor facilities, and the leak of radioactive substance did not occur at all. But the investigation was made extensively by the joint committee of both houses, the government and others, and the deficiency in the countermeasures to fire was found, and it was clarified that some revision would by required on the standard applied heretofore. It was the valuable experience for improving further the safety of nuclear power stations. The fire occurred by the ignition of the polyurethane for sealing cable penetrations due to candle flame for testing. About 1600 cables were burned. When fire breaks out in a nuclear power station, it is necessary to stop and cool the reactor without fail, and to prevent the leak of radioactive substances definitely. In case of the fire in Browns Ferry, these requirements were fulfilled satisfactorily. The countermeasures on the basis of the experience in Browns Ferry and the design of the counterplan to fire in nuclear power stations are explained. (Kako, I.)

  7. Physical Protection of Nuclear Material and Nuclear Facilities (Implementation of INFCIRC/225/Revision 5). Implementing Guide

    International Nuclear Information System (INIS)

    2018-01-01

    This publication is the lead Implementing Guide in a suite of guidance on implementing the Nuclear Security Recommendations on Physical Protection of Nuclear Material and Nuclear Facilities (INFCIRC/225/Revision 5), IAEA Nuclear Security Series No. 13. It provides guidance and suggestions to assist States and their competent authorities in establishing, strengthening and sustaining their national physical protection regime and implementing the associated systems and measures, including operators’ physical protection systems. The structure of this publication is as follows. After this introduction, Section 2 describes the objectives of physical protection and the overall approach to managing the risks of the unauthorized removal of nuclear material and the sabotage of nuclear facilities. Section 3 provides guidance for the State and its competent authorities on the physical protection elements of the nuclear security regime; this guidance is based on the fundamental principles set out in the Recommendations publication. Section 4 provides guidance on the operator’s physical protection system and describes a systematic, integrated approach. Appendix I gives an annotated outline of the typical contents of an operator’s security plan. Appendix II provides similar guidance for the contingency plan. Appendix III provides a description of nuclear material aggregation that can be used to categorize nuclear material and determine the appropriate level of protection against unauthorized removal. Appendix IV presents a table of paragraph cross-references between the Recommendations publication and this Implementing Guide.

  8. Radioprotective shield - an adequate radioprotective device for routine stomatological radiodiagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Wiltschke, F [Ernst-Moritz-Arndt-Univ., Greifswald (German Democratic Republic); Taschner, P; Koenig, W; Menzel, B [Staatliches Amt fuer Atomsicherheit und Strahlenschutz, Berlin (German Democratic Republic)

    1975-01-01

    Starting from the shortcomings of the radioprotective devices at present used in routine stomatological radiodiagnosis, the authors describe the advantages of a radioprotective shield which has been produced in the Greifswald University Stomatological Clinic. On the basis of dosimetric studies, the National Board for Nuclear Safety and Radiological Protection of the GDR (Staatliches Amt fuer Atomsicherheit und Strahlenschutz der DDR) could demonstrate the suitability of this shield as a radioprotective device for routine stomatological radiodiagnosis.

  9. Organisation and tasks concerning population protection in nuclear accident

    International Nuclear Information System (INIS)

    Nikolov, N.

    1995-01-01

    The structure and the scope of activities of Civil Defense Administration of Bulgaria are briefly outlined. Protection of general public in the case of nuclear accident will be provided according to a special off-site emergency plan. The plan is based on results of research and development approved by the permanent commission for public protection. 3 refs

  10. Organisation and tasks concerning population protection in nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Nikolov, N [Civil Defence Administration, Sofia (Bulgaria)

    1996-12-31

    The structure and the scope of activities of Civil Defense Administration of Bulgaria are briefly outlined. Protection of general public in the case of nuclear accident will be provided according to a special off-site emergency plan. The plan is based on results of research and development approved by the permanent commission for public protection. 3 refs.

  11. Revision of the protective action guides manual for nuclear incidents

    International Nuclear Information System (INIS)

    DeCair, S.; MacKinney, J.

    2007-01-01

    EPA's 1992 Manual of Protective Action Guides and Protective Actions for Nuclear Incidents, referred to as the PAG Manual, is a radiological emergency planning and response tool for emergency management officials at the Federal, state, tribal, and local levels. A Protective Action Guide is defined as, the projected dose to reference man, or other defined individual, from a release of radioactive material at which a specific protective action to reduce or avoid that dose is recommended'. The updated version of the PAG Manual accomplishes these key objectives: applying the existing 1992 protective action guides and protective actions to new radiological and nuclear scenarios of concern; updating the dosimetry basis; lowering the recommended dose for administration of stable iodine; providing new guidance concerning consumption of drinking water during or after a radiological emergency; updating the dosimetry basis for all derived levels, and, adding guidance for dealing with long-term site restoration following a major radiological release. (author)

  12. A National Institute of Radiation Protection and Nuclear Safety?

    International Nuclear Information System (INIS)

    Hartley, B.M.

    1993-01-01

    The practice of radiation protection within Australia is fragmented on a number of different levels. Each state has its own radiation protection organisation. Within the Commonwealth there is also a large number of bodies which deal with different aspects of radiation protection or nuclear safety. There is also an interest in occupational radiation protection by Departments responsible for Occupational Health and Safety. It is estimated that this fragmentation affects the practice of radiation protection at a State level and also the role which Australia can play internationally. The establishment of a National Institute of Radiation Protection and Nuclear Safety is therefore proposed. Possible structures and organizational arrangements for such an institute are discussed. 4 refs., 4 tabs., 3 figs

  13. Contamination shield

    International Nuclear Information System (INIS)

    Bayer, W.; Pecornik, D.

    1982-01-01

    An acrylate resin is presented as contamination protection coating for components and instruments in nuclear facilities and for spent fuel transport containers. The resin is evaporated or sublimated at 130 0 C and can thus be removed easily from the protected component. The radioactive particles entrained during evaporation are retained by suitable filters. (TK) [de

  14. Technical experience of the Belgian regulatory body regarding shielded cells

    International Nuclear Information System (INIS)

    Cortenbosch, G.; Degreef, G.; Noterman, N.; Mommaert, C.; Smidts, O.; Hasendonck, M. van; Drymael, H.; Schmitz, F.; Kennes, C.; Carlier, P.

    2010-01-01

    Radiation protection and nuclear safety are of paramount importance when operating shielded cells in hot labs and using remote handling tools. Therefore, various aspects should be ensured throughout the lifecycle of nuclear installations disposing of such type of equipment. The presented aspects are the results of the regulatory body experience with this kind of installations (licensing, operations, operating experience, events). This paper will deal with safety considerations such as filtration, fire protection, shielding, ventilation, waste management, separation of the product fluxes, leak tightness, introduction of equipment, interlocks, failsafe components, piloting software, monitoring and education/training. (orig.)

  15. Training of fire protection personnel in nuclear power plants

    International Nuclear Information System (INIS)

    Blaser, W.

    1980-01-01

    Training of fire protection personnel in nuclear power plants is divided up in three categories: training of fire protection commissioners which is mostly carried out externally; training of fire fighting personnel in the form of basic and repeated training usually by the fire protection commissioner; training of other employers with regard to behaviour in case of fire and during work involving a fire hazard. (orig.) [de

  16. TIBER II/ETR [Engineering Test Reactor] nuclear shielding and optional tritium breeding system: An overview

    International Nuclear Information System (INIS)

    Lee, J.D.; Sawan, M.

    1987-01-01

    TIBER II, the Tokamak Ignition/Burn Experimental Reactor II, is a design concept developed as the US candidate for an International Engineering Test Reactor (ETR). An important objective of this design is to minimize cost by minimizing major radius while providing a wall loading greater than 1.0 MW/m2 and a total fluence greater than 3.0 MWY/m2 needed for blanket module testing. The shielding required for the superconducting TF coils is an important element in setting TIBER II's 3.0m major radius. 6 refs., 1 fig., 1 tab

  17. Safety guide on fire protection in nuclear power plants

    International Nuclear Information System (INIS)

    1976-01-01

    The purpose of the Safety Guide is to give specific design and operational guidance for protection from fire and explosion in nuclear power plants, based on the general guidance given in the relevant sections of the 'Safety Code of Practice - Design' and the 'Safety Code of Practice - Operation' of the International Atomic Energy Agency. The guide will confine itself to fire protection of safety systems and items important to safety, leaving the non-safety matters of fire protection in nuclear power plants to be decided upon the basis of the various available national and international practices and regulations. (HP) [de

  18. Quantitative evaluation of physical protection system in nuclear power plant

    International Nuclear Information System (INIS)

    Sun Yahua; Li Bin; Li Shiju

    2009-01-01

    Based on the prompt detection analysis, this paper introduced one analysis model of intrusion path in nuclear power plant by means of morphology analysis and developed the evaluation software for path model analysis of physical protection system. Quantitative analysis on three elements (detection, delay, and response) of physical protection system was presented with an imaginary intrusion event example in Mac Arthur nuclear center. The results indicated that the path prompt detection analysis worked effectively to find the weak point of the physical protection system in NPP, and meantime we can also get the high cost-effectiveness improved measures. It is an effective approach to evaluate the overall performance of the system. (authors)

  19. Provision of operational radiation protection services at nuclear power plants

    International Nuclear Information System (INIS)

    1990-01-01

    The purpose of this publication is to provide practical guidance on establishing and maintaining a radiation protection programme for a nuclear power plant that is consistent with the optimization process recommended in the Basic Safety Standards. This publication is written with a view to providing guidance to every person associated with the radiation protection programme for a nuclear power plant and develops the theme that radiation protection requires the commitment of all plant staff, including higher levels of executive management. 12 refs, 2 figs

  20. New nuclear build and evolving radiological protection challenges

    International Nuclear Information System (INIS)

    Lazo, T.

    2010-01-01

    Many trends and indicators suggest that the use of nuclear power for generating electricity will increase, perhaps significantly, in the coming 10 to 20 years and beyond. Any such expansion will not take place in a static scientific or social context, but rather in the midst of ongoing changes in many relevant fields, radiological protection, radioactive waste management and nuclear safety to name a few. Regarding radiological protection, this evolution can be characterised in many different ways, but can conveniently be described as having scientific and socially driven aspects. These may well pose challenges to radiological protection (RP) policy, regulation and application in the future

  1. Dictionary of radiation protection, radiobiology and nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Sube, R [comp.

    1986-01-01

    Radiation protection, including aspects of radiobiology, nuclear medicine, and nuclear legislation, has an important role within nuclear research and the use of radioactive materials. Radiation protection comprises all measures and efforts to prevent the unwanted distribution and negative influence of ionizing radiation, especially where the human organism and the living environment are involved. The increasing role of radiation protection is reflected by the foundation of institutes in all industrial countries to control such radiant energy and prevent radiation damage. Nowadays ionizing radiation is employed on a large scale for basic investigations in biochemistry, molecular biology and genetics, in soil tests, fertilization problems and pest control in agriculture, as well as for medicinal diagnoses and therapy. This dictionary is a thematic enlargement of the four-language 'Dictionary of Nuclear Engineering', compiled by the same author. It comprises about 12,000 terms in each language.

  2. Dictionary of radiation protection, radiobiology and nuclear medicine

    International Nuclear Information System (INIS)

    Sube, R.

    1986-01-01

    Radiation protection, including aspects of radiobiology, nuclear medicine, and nuclear legislation, has an important role within nuclear research and the use of radioactive materials. Radiation protection comprises all measures and efforts to prevent the unwanted distribution and negative influence of ionizing radiation, especially where the human organism and the living environment are involved. The increasing role of radiation protection is reflected by the foundation of institutes in all industrial countries to control such radiant energy and prevent radiation damage. Nowadays ionizing radiation is employed on a large scale for basic investigations in biochemistry, molecular biology and genetics, in soil tests, fertilization problems and pest control in agriculture, as well as for medicinal diagnoses and therapy. This dictionary is a thematic enlargement of the four-language 'Dictionary of Nuclear Engineering', compiled by the same author. It comprises about 12,000 terms in each language. (orig.)

  3. Status of physical protection systems of nuclear facilities; survey report

    International Nuclear Information System (INIS)

    Hwang, In Koo; Kwack, Eun Ho; Ahn, Jin Soo; Lee, Hyun Chul; Kim, Jung Soo

    2002-02-01

    This report presents a survey on the physical protection equipment for a nuclear power plant. This survey was conducted by Korea Atomic Energy Research Institute as a part of the project, 'Development of Technologies for National Control of and Accountancy for Nuclear Material,' funded by the Ministry of Science and Technology of Korea. A physical protection system of a nuclear plant includes outer and inner fences, intrusion detection sensors, alarm generation system, illumination equipment, central monitoring and control station, entry control and management system, etc. The outermost fence indicates the boundary of the plant area and prevents a simple or unintentional intrusion. The inner fence area of each plant unit associated with intrusion detection sensors, illuminators, monitoring cameras, serves the key role for physical protection function for the nuclear plant

  4. Nuclear Safety and Radiation Protection in Europe - a common approach

    International Nuclear Information System (INIS)

    McGarry, Ann

    2010-01-01

    In Europe, the European Union has adopted directives and implemented other measures which form the basis of a common approach to nuclear safety and radiation protection across all Member States. In particular, there are EU directives setting out radiation protection standards and establishing a Community framework for the nuclear safety of nuclear installations. There are also arrangements in place to provide for an effective response to nuclear emergencies and to facilitate high quality research into nuclear and radiation protection related topics. Inevitably the stage of development in each area is somewhat different, but generally progress is ongoing in each area. From the point of view of a small country like Ireland, the development of common standards and arrangements across Europe is beneficial as they are based on the best available knowledge and expertise; they provide for greater transparency; they facilitate public confidence and make best use of the available resources. However, there are some areas in which common approaches could be further advanced. For example, the medical exposure of patients is increasingly of concern across Europe and the further development of common approaches in this area would be helpful. It would also be useful to develop a more integrated approach to nuclear safety and radiation protection regulation and to better integrate nuclear and radiation issues with other public health and environment concerns. (author)

  5. Environmental protection and international law: the case of nuclear energy

    International Nuclear Information System (INIS)

    Dagicour, F.

    2002-03-01

    Given the very hazardous nature of its activity, the nuclear industry has often been considered to be without a future. Concerns over climate change and increasing international energy needs have, however, shone a new light on the positive aspects of nuclear energy. As the only clean, stable and inexpensive energy source, available, nuclear energy promises a constant supply of electricity while protecting the atmosphere. This new relationship between the environment and nuclear energy calls for an analysis of the international regulation of the risks posed by nuclear energy production. Since the beginning of the nuclear age, the long term, unknown, and large geographic scope of the risks and effects of this activity have led to the adoption of a set of normative rules outside of the scope of international environmental law. The norms that now regulate this new, ultra-hazardous activity resulted in a set of rules aimed at protecting the environment in the face of high risk activities that now form the heart of international environmental law. Unwilling relinquish national sovereignty, States adopted a system of non-binding regulation to protect the environment and promote the nuclear industry. The Chernobyl accident later pointed to the weakness of this approach. Despite this weakness, the adoption of a soft law approach has led to progress in environmental protection in an area where States have been loathe to give up their sovereignty. (author)

  6. Shielded cells transfer automation

    International Nuclear Information System (INIS)

    Fisher, J.J.

    1984-01-01

    Nuclear waste from shielded cells is removed, packaged, and transferred manually in many nuclear facilities. Radiation exposure is absorbed by operators during these operations and limited only through procedural controls. Technological advances in automation using robotics have allowed a production waste removal operation to be automated to reduce radiation exposure. The robotic system bags waste containers out of glove box and transfers them to a shielded container. Operators control the system outside the system work area via television cameras. 9 figures

  7. The nuclear shield in the 'thirty-year war' of physicists against ignorant criticism of modern physical theories

    International Nuclear Information System (INIS)

    Vizgin, Vladimir P

    1999-01-01

    This article deals with the almost 'thirty-year war' led by physicists against the authorities' incompetent philosophical and ideological interference with science. The 'war' is shown to have been related to the history of Soviet nuclear weapons. Theoretical milestones of 20th century physics, to wit, theory of relativity and quantum mechanics, suffered endless 'attacks on philosophical grounds'. The theories were proclaimed idealistic as well as unduly abstract and out of touch with practice; their authors and followers were labelled 'physical idealists', and later, in the 1940s and 1950s, even 'cosmopolitans without kith or kin'. Meanwhile, quantum and relativistic theories, as is widely known, had become the basis of nuclear physics and of the means of studying the atomic nucleus (charged particle accelerators, for instance). The two theories thus served, to a great extent, as a basis for both peaceful and military uses of nuclear energy, made possible by the discovery of uranium nuclear fission under the action of neutrons. In the first part, the article recounts how prominent physicists led the way to resisting philosophical and ideological pressure and standing up for relativity, quantum theories and nuclear physics, thus enabling the launch of the atomic project. The second part contains extensive material proving the point that physicists effectively used the 'nuclear shield' in the 1940s and 1950s against the 'philosophical-cosmopolitan' pressure, indeed saving physics from a tragic fate as that of biology at the Academy of Agricultural Sciences (VASKhNIL) session in 1948. (from the history of physics)

  8. 21. century challenges in radiation protection and shielding: Draft 2005 recommendations of ICRP

    International Nuclear Information System (INIS)

    Clarke, R.

    2005-01-01

    The International Commission on Radiological Protection regularly examines the status of its recommendations and reviews the increasing knowledge of the effects of exposure to ionising radiation in order to decide whether new recommendations are needed. The Commission strives to make its system more coherent and comprehensible, while recognising the need for stability in international and national regulations, many of which have, only fairly recently, implemented the 1990 Recommendations. However, new scientific data have been produced since 1990 and there have been societal developments in that more openness or transparency is expected in developing new recommendations and, in addition, there has been a move from the utilitarian approach of 'the greatest good for the greatest number', to one with more concern for the 'individual', all of which have inevitably led to some changes in the formulation of the recommendations. This paper outlines the proposals for the 2005 Recommendations. (authors)

  9. Fire protection and fire fighting in nuclear installations

    International Nuclear Information System (INIS)

    1989-01-01

    Fires are a threat to all technical installations. While fire protection has long been a well established conventional discipline, its application to nuclear facilities requires special considerations. Nevertheless, for a long time fire engineering has been somewhat neglected in the design and operation of nuclear installations. In the nuclear industry, the Browns Ferry fire in 1975 brought about an essential change in the attention paid to fire problems. Designers and plant operators, as well as insurance companies and regulators, increased their efforts to develop concepts and methods for reducing fire risks, not only to protect the capital investment in nuclear plants but also to consider the potential secondary effects which could lead to nuclear accidents. Although the number of fires in nuclear installations is still relatively large, their overall importance to the safety of nuclear power plants was not considered to be very high. Only more recently have probabilistic analyses changed this picture. The results may well have to be taken into account more carefully. Various aspects of fire fighting and fire protection were discussed during the Symposium, the first of its kind to be organized by the IAEA. It was convened in co-operation with several organizations working in the nuclear or fire protection fields. The intention was to gather experts from nuclear engineering areas and the conventional fire protection field at one meeting with a view to enhancing the exchange of information and experience and to presenting current knowledge on the various disciplines involved. The presentations at the meeting were subdivided into eight sessions: standards and licensing (6 papers); national fire safety practices (7 papers); fire safety by design (11 papers); fire fighting (2 papers); computer fire modeling (7 papers); fire safety in fuel center facilities (7 papers); fire testing of materials (3 papers); fire risk assessment (5 papers). A separate abstract was

  10. General fire protection guidelines for egyptian nuclear facilities. Vol. 4

    Energy Technology Data Exchange (ETDEWEB)

    Radhad, S; Hussien, A Z; Hammad, F H [National Center for Nuclear Safety and Radiation Control, Atomic Energy Authority, Cairo (Egypt)

    1996-03-01

    The purpose of this paper is to establish the regulatory requirements of that will provide and ensure fire protection of egyptian nuclear facilities. Those facilities that use, handle and store low and/or medium radioactive substances are included. Two or more classes of occupancy are considered to occur in the same building or structure. Fir protection measures and systems were reviewed for three of the egyptian Nuclear facilities. These are egypt first nuclear reactor (ETRR-1) building and systems, hot laboratories buildings and facilities, and the building including the AECL type Is-6500 industrial cobalt-60 gamma irradiator {sup E}gypt`s mega gamma I{sup .} The study includes the outlines of the various aspects of fire protection with a view to define the relevant highlights and scope of egyptian guideline for nuclear installations. The study considers fire protection aspects including the following items: 1- Site selection. 2- General facility design. 3- Fire alarm, detection and suppression systems. (4- Protection for specific areas/control room, cable spreading room, computer room) 5- Fire emergency response planning. 6- Fire water supply. 7- Emergency lighting and communication. 8- Rescue and escape routes. 9- Explosion protection. 10-Manual fire fighting. 11- Security consideration in the interest of fire protection. 12- quality assurance programme. Therefore, first of all the design stage, then during the construction stage, and later during the operation stage, measures must be taken to forestall the risks associated with the outbreak of fire and to ensure that consequences of fire accidents remain limited.

  11. EPRI Guide to Managing Nuclear Utility Protective Clothing Programs

    International Nuclear Information System (INIS)

    Kelly, J.J.; Kelly, D.M.

    1993-10-01

    The Electric Power Research Institute (EPRI) commissioned a radioactive waste related project (RP2414-34) in 1989 to produce a guide for developing and managing nuclear plant protective clothing programs. Every nuclear facility must coordinate some type of protective clothing program for its radiation workers to ensure proper and safe protection for the wearer and to maintain control over the spread of contamination. Yet, every nuclear facility has developed its own unique program for managing such clothing. Accordingly, a need existed for a reference guide to assist with standardizing protective clothing programs and in controlling the potentially escalating economics of such programs. The initial Guide to Managing Nuclear Utility Protective Clothing Programs, NP-7309, was published in May 1991. Since that time, a number of utilities have reviewed and/or used the report to enhance their protective clothing programs. Some of these utilities requested that a computer program be developed to assist utilities in evaluating the economics of protective clothing programs consistent with the guidance in NP-7309. The PCEVAL computer code responds to that industry need. This report, the PCEVAL User's Manual, provides detailed instruction on use of the software

  12. General fire protection guidelines for egyptian nuclear facilities. Vol. 4

    International Nuclear Information System (INIS)

    Radhad, S.; Hussien, A.Z.; Hammad, F.H.

    1996-01-01

    The purpose of this paper is to establish the regulatory requirements of that will provide and ensure fire protection of egyptian nuclear facilities. Those facilities that use, handle and store low and/or medium radioactive substances are included. Two or more classes of occupancy are considered to occur in the same building or structure. Fir protection measures and systems were reviewed for three of the egyptian Nuclear facilities. These are egypt first nuclear reactor (ETRR-1) building and systems, hot laboratories buildings and facilities, and the building including the AECL type Is-6500 industrial cobalt-60 gamma irradiator E gypt's mega gamma I . The study includes the outlines of the various aspects of fire protection with a view to define the relevant highlights and scope of egyptian guideline for nuclear installations. The study considers fire protection aspects including the following items: 1- Site selection. 2- General facility design. 3- Fire alarm, detection and suppression systems. 4- Protection for specific areas/control room, cable spreading room, computer room) 5- Fire emergency response planning. 6- Fire water supply. 7- Emergency lighting and communication. 8- Rescue and escape routes. 9- Explosion protection. 10-Manual fire fighting. 11- Security consideration in the interest of fire protection. 12- quality assurance programme. Therefore, first of all the design stage, then during the construction stage, and later during the operation stage, measures must be taken to forestall the risks associated with the outbreak of fire and to ensure that consequences of fire accidents remain limited

  13. Protection and safety of nuclear power stations

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    The extreme requirements for the safety of nuclear power stations set tasks to the civil engineer which, resulting from dynamic load assumptions, among other things also demand the development of novel special concrete steels with a high elastic limit (here: DYWIDAG thread tie rod) for singly reinforced members. (orig.) [de

  14. Criticality and shielding calculations of an interim dry storage system for the spent fuel from Atucha I Nuclear Power Plant

    International Nuclear Information System (INIS)

    Silva, M

    2006-01-01

    The Atucha I Nuclear Power Plant (CNA-I) has enough room to store its spent fuel (SF) in damp in its two pool houses until the middle of 2015.Before that date there is the need to have an interim dry storage system for spent fuel that would make possible to empty at least one of the pools, whether to keep the plant operating if its useful life is extended, or to be able to empty the reactor core in case of decommissioning.Nucleolectrica Argentina S.A. (NA-SA) and the Comision Nacional de Energia Atomica (CNEA), due to their joint responsibility in the management of the SF, have proposed interim dry storage systems.These systems have to be evaluated in order to choose one of them by the end of 2006.In this work the Monte Carlo code MCNP was used to make the criticality and shielding calculations corresponding to the model proposed by CNEA.This model suggests the store of sealed containers with 36 or 37 SF in concrete modules.Each one of the containers is filled in the pool houses and transported to the module in a transference cask with lead walls.The results of the criticality calculations indicates that the solutions of SF proposed have widely fulfilled the requirements of subcriticality, even in supposed extreme accidental situations.Regarding the transference cask, the SF dose rate estimations allow us to make a feedback for the design aiming to the geometry and shielding improvements.Regarding the store modules, thicknesses ranges of concrete walls are suggested in order to fulfill the dose requirements stated by the Autoridad Regulatoria Nuclear Argentina [es

  15. International guidelines for fire protection at nuclear installations including nuclear fuel plants, nuclear fuel stores, teaching reactors, research establishments

    International Nuclear Information System (INIS)

    The guidelines are recommended to designers, constructors, operators and insurers of nuclear fuel plants and other facilities using significant quantities of radioactive materials including research and teaching reactor installations where the reactors generally operate at less than approximately 10 MW(th). Recommendations for elementary precautions against fire risk at nuclear installations are followed by appendices on more specific topics. These cover: fire protection management and organization; precautions against loss during construction alterations and maintenance; basic fire protection for nuclear fuel plants; storage and nuclear fuel; and basic fire protection for research and training establishments. There are numerous illustrations of facilities referred to in the text. (U.K.)

  16. Design and evaluation of physical protection systems of nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    An, Jin Soo; Lee, Hyun Chul; Hwang, In Koo; Kwack, Eun Ho; Choi, Yung Myung

    2001-06-01

    Nuclear material and safety equipment of nuclear facilities are required to be protected against any kind of theft or sabotage. Physical protection is one of the measures to prevent such illegally potential threats for public security. It should cover all the cases of use, storage, and transportation of nuclear material. A physical protection system of a facility consists of exterior intrusion sensors, interior intrusion sensors, an alarm assessment and communication system, entry control systems, access delay equipment, etc. The design of an effective physical protection system requires a comprehensive approach in which the designers define the objective of the system, establish an initial design, and evaluate the proposed design. The evaluation results are used to determine whether or not the initial design should be modified and improved. Some modelling techniques are commonly used to analyse and evaluate the performance of a physical protection system. Korea Atomic Energy Research Institute(KAERI) has developed a prototype of software as a part of a full computer model for effectiveness evaluation for physical protection systems. The input data elements for the prototype, contain the type of adversary, tactics, protection equipment, and the attributes of each protection component. This report contains the functional and structural requirements defined in the development of the evaluation computer model.

  17. The manufacturing of depleted uranium biological shield components

    International Nuclear Information System (INIS)

    Metelkin, J.A.

    1998-01-01

    The unique combination of the physical and mechanical properties of uranium made it possible to manufacture biological shield components of transport package container (TPC) for transportation nuclear power plant irradiated fuel and radionuclides of radiation diagnostic instruments. Protective properties are substantially dependent on the nature radionuclide composition of uranium, that why I recommended depleted uranium after radiation chemical processing. Depleted uranium biological shield (DUBS) has improved specific mass-size characteristics compared to a shield made of lead, steel or tungsten. Technological achievements in uranium casting and machining made it possible to manufacture DUBS components of TPC up to 3 tons of mass and up to 2 metres of the maximum size. (authors)

  18. The application of semianalytic method for calculating the thickness of biological shields of nuclear reactors. Part 2. Attenuation of gamma rays. An example of shield's thickness calculation

    International Nuclear Information System (INIS)

    Lukaszek, W.; Kucypera, S.

    1982-01-01

    The semianalytic method was used for calculating the attenuation of gamma rays and the thickness of biological shield of graphite moderated reactor. A short description of computer code as well as the exemplary results of calculations are given. (A.S.)

  19. The EURATOM legal framework in health protection and nuclear safety

    International Nuclear Information System (INIS)

    Mondoloni, F.

    2010-01-01

    The EURATOM treaty and its derived legislation constitute a standardised base to support the development of nuclear power throughout the European Union. Health protection against the effects of radioactivity and nuclear safety are a key component of this system. For 50 years, common obligations have been gradually defined and updated to guarantee radiological protection of the peoples and the environment of Europe. At a time when increasing numbers of countries are looking to switch to or strengthen the position of nuclear power in their energy mix, health protection issues are once again topical. The Commission is taking advantage of this particular context to propose new standards, while at the same time internationally promoting the idea of a European regulatory model. Europe, whose technological expertise in the nuclear field is undisputed, has everything to gain from disseminating its radiation protection and nuclear safety values worldwide. However, while exploring new areas for community harmonization in these fields, a necessary balance needs to be retained with national systems which have proven their worth, while taking account of the respective competence of the Community and the Member States. It is by defending national positions with the community institutions that it is possible to contribute to this balance. The General Secretariat for European Affairs (SGAE), the EURATOM technical committee (CTE) and France's Permanent Representation in Brussels, form an effective system for formulating and defending these positions, thus helping to orient community work on nuclear issues. (author)

  20. The Australian radiation protection and Nuclear Safety Agency

    International Nuclear Information System (INIS)

    Macnab, D.; Burn, P.; Rubendra, R.

    1998-01-01

    The author talks about the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA), the new regulatory authority which will combine the existing resources of the Australian Radiation Laboratory and the Nuclear Safety Bureau. Most uses of radiation in Australia are regulated by State or Territory authorities, but there is presently no regulatory authority for Commonwealth uses of radiation. To provide for regulation of the radiation practices of the Commonwealth, the Australian Government has decided to establish the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) and a Bill has passed through the House of Representatives and will go to the Spring sitting of the Senate. The new agency will subsume the resources and functions of the Nuclear Safety Bureau and the Australian Radiation Laboratory, with additional functions including the regulation of radiation protection and nuclear safety of Commonwealth practices. Another function of ARPANSA will be the promotion of uniform regulatory requirements for radiation protection across Australia. This will be done by developing, in consultation with the States and Territories, radiation health policies and practices for adoption by the Commonwealth, States and Territories. ARPANSA will also provide research and services for radiation health, and in support of the regulatory and uniformity functions. The establishment of ARPANSA will ensure that the proposed replacement research reactor, the future low level radioactive waste repository and other Commonwealth nuclear facilities and radiation practices are subject to a regulatory regime which reflects the accumulated experience of the States and Territories and best international practice, and meets public expectations

  1. Spin-orbit ZORA and four-component Dirac-Coulomb estimation of relativistic corrections to isotropic nuclear shieldings and chemical shifts of noble gas dimers

    DEFF Research Database (Denmark)

    Jankowska, Marzena; Kupka, Teobald; Stobiński, Leszek

    2016-01-01

    Hartree-Fock and density functional theory with the hybrid B3LYP and general gradient KT2 exchange-correlation functionals were used for non-relativistic and relativistic nuclear magnetic shielding calculations of helium, neon, argon, krypton and xenon dimers and free atoms. Relativistic...

  2. Organization of nuclear safety and radiation protection in Switzerland

    International Nuclear Information System (INIS)

    Pretre, S.

    1995-01-01

    In Switzerland an important distinction is made between radiation protection (in charge of the use of ionizing radiations for medical uses or non nuclear industry), and nuclear safety (in charge of nuclear industry, including prevention or limitation of any risk of nuclear accident). In the eighties, it has been decided to make two laws for these two topics. The law for radioprotection, voted in 1991 is enforced since 1994 by OFSP (Office Federal de la Sante Publique). It performs any radiation monitoring outside nuclear industry plants. The law for nuclear safety, that should be enforced by OFEN (Office Federal de l'ENergie), is still not voted. The only existing legislation is the 1959 atomic law. (D.L.). 1 fig., 1 map

  3. Halon 1301 protection system for nuclear containments

    International Nuclear Information System (INIS)

    McHale, E.T.

    1981-01-01

    Halon 1301 can provide protection against any combustion hazard that hydrogen gas might present in an LWR containment following a loss-of-coolant accident. A development program was conducted, comprising analytical study, laboratory experiments and large-scale testing, to define the requirements for a Halon 1301 system and to examine certain operational problems that were hypothesized. Some results of the study are presented in this paper

  4. Strengthened implementation of physical protection of nuclear material and nuclear facilities in the Republic of Korea

    International Nuclear Information System (INIS)

    Shim, H.-W.; Lee, J.-U.

    2005-01-01

    Full text: Since the 9.11 terror, strengthening physical protection has been an accelerated trend internationally. IAEA has been requesting that member states implement a strengthened physical protection of nuclear facilities on the basis of threat assessments. In order to cope with this demand, the Korean government promulgated the 'Law for Physical Protection and Radiological Emergency Preparedness (LPPRE)' as a substantial countermeasure against possible threats. Pursuant to LPPRE, which entered into force on February 16, 2004, nuclear enterprisers are obliged to implement an effective physical protection of nuclear materials, get approval for its physical protection system, and be constantly inspected on. The Ministry of Science and Technology (MOST) approved physical protection regulations of 24 domestic facilities operated by 14 enterprisers. National Nuclear management and Control Agency (NNCA) is entrusted with physical protection related duty and has been conducting physical protection inspection on nuclear materials in use, storage and transport. In addition, NNCA has established the methodology of threat assessment that entails organizing the threat assessment working group to develop a design basis threat (DBT). Korea is putting its best efforts to construct the threat assessment system and strengthen domestic physical protection regime in cooperation with competent authorities. (author)

  5. Radiological protection of patients in nuclear medicine

    International Nuclear Information System (INIS)

    Harding, L.K.

    2001-01-01

    The key factor in medical exposure is justification, that is ensuring that the benefit exceeds the risk. Nuclear medicine studies are comparable in cost to more sophisticated radiological tests such as ultrasound, computed tomography or magnetic resonance. Radiation doses are similar from X ray and nuclear medicine procedures. Having justified exposures the next step is optimization, namely using a radiation dose as low as is reasonably practicable. Diagnostic reference levels may be set nationally or locally such that the balance of diagnostic quality and radiation burden is optimized. In therapy the aim is to achieve a therapeutic dose while keeping the dose to non-target tissues as low as reasonably practicable. Variations in activities may be required for overweight patients, those in severe pain, those with certain conditions and in the case of tomography. Any woman who has missed a period should be assumed to be pregnant; there should be notices to patients emphasizing this. Following the administration of longer lived pharmaceuticals it is important to avoid pregnancy for a time such that the dose to a foetus will not exceed 1 mGy. A similar situation applies to a child who is being breastfed when a mother receives a radiopharmaceutical. In the case of children undergoing investigations the activity needs to be reduced to maintain the same count density as in adults. With the administration of an incorrect pharmaceutical an attempt should be made to enhance excretion, and the referring doctor and the patient should be informed. Extravasation usually requires no action. Positron emission tomography results in higher doses both to staff and patients. Research should use subjects over the age of 50, and avoid anyone who is pregnant or is a child. Nuclear medicine procedures result in a very small loss in life expectancy compared with other common risks. (author)

  6. The radiological protection in the nuclear medicine practice

    International Nuclear Information System (INIS)

    Maldonado M, H.

    2010-09-01

    The nuclear medicine practice dates of the 1950 years, in this work the achievements reached as regards radiological protection are shown, although even lack a lot to make, the doses for the occupationally exposed personnel have decreased with lapsing of the years, thanks to the perception of the nuclear physicians to improve the administration techniques of the radioactive material, the decrease of administered activity and the unit doses use among the most remarkable advances. The changes in the equipment s technology to quantify the activity to administer, detection systems and image formation have demanded the development of the new professionals of the nuclear medicine that allows give protection to the patient. This improvement needs to consolidate with the appropriate normative development, the involved personnel qualification and the methods and procedures actualization to improve the protection of the occupationally exposed personnel, the public, the environment and the patient. (Author)

  7. Nuclear medicine and its radiological protection in China

    International Nuclear Information System (INIS)

    Wu, J.

    2001-01-01

    The China Society of Nuclear Medicine was established on 27 May 1980. Since then, nuclear medicine in clinical diagnosis and therapy has been developed rapidly in China. So far there are more than 4000 members of the Society, and more than 350 sets of SPECT and 12 sets of PET have been installed and are busily running in clinic nowadays and about 1 million patients with different types of diseases have obtained nuclear medicine imaging examinations per year. Concerning the nuclear medicine therapy, a lot of patients with many types of diseases obtained benefit from radioisotope therapy. Accordingly, several Policies and Regulations have been enacted by the Government for the radiological protection. Furthermore, a special book titled 'Standardization in Diagnostic and Therapeutic Nuclear Medicine' has been promulgated in June, 1997 by the Health Administration of People's Republic of China, and this book is distributed to almost every nuclear medicine physician and technician in China for their reference in routine nuclear medicine work or research. In this book three parts of the contents are covered: Policies and Regulations for the radiological protection, basic knowledge and clinical nuclear medicine applications. (author)

  8. Development of a pencil-type single shield graphite quasi-adiabatic calorimeter and comparison of its performance with a double-shield graphite calorimeter for the measurement of nuclear heat deposition rate in a fusion environment

    International Nuclear Information System (INIS)

    Joneja, O.P.; Rosselet, M.; Ligou, J.; Gardel, P.

    1995-01-01

    Recently, heat deposition rate measurements were reported that used a quasi-adiabatic double-shield graphite calorimeter. It was found that for a better understanding of nuclear heating due to incident radiation, having a calorimeter that could be conveniently moved axially and radially inside large material blocks would be advisable. Here, a simpler design, based on three elements, i.e., core, jacket, and shield is conceived. The fabrication and testing details are presented, and the performance of the current calorimeter is compared with a double-shield calorimeter under similar conditions. Such a system is found to be extremely sensitive and can be employed successfully at the LOTUS facility for future nuclear heat deposition rate measurements in large blocks of materials. The current design paves the way for the convenient testing of a large amount of kerma factor data required for constructing future fusion machines. The same configuration with minor changes can be extended to most of the fusion materials of interest. The core of the new calorimeter measures 11 mm in diameter and height and has overall dimensions of 24 mm in diameter and 180 mm in height. The response of the calorimeter is measured by placing it in front of the Haefely neutron generator. 12 refs., 16 figs., 9 tabs

  9. Physical protection of nuclear materials and facilities in CEA

    International Nuclear Information System (INIS)

    Garnier-Gratia, M.-H.; Jorda, A.

    2001-01-01

    Full text: CEA (Commissariat a l'Energie Atomique), as nuclear operator, is responsible for the control and protection of their nuclear materials. Inside CEA, DCS (Central Security Division) is in charge of the security matters, DCS defines the CEA strategy in this field, especially in physical protection. The paper will present the physical protection strategy of CEA. DCS defines the rules and methods; the operators have to apply in order to fulfill the security objectives of CEA. CEA has to provide the regulatory authority with documents proving that it is in accordance with the requirements of the 25th July 1980 law and 12th May 1981 decree. It has to implement all the necessary means in order to achieve the results requested by the regulatory authority. All these arrangements are described in the 'license and control file'. This file should specify the facility safeguards and physical protection system. Accounting measures are also described. In this file, the petitioner has to justify its capacity for holding nuclear materials and for exercising authorized activities on them. So the organization and the installed means have to be described in this authorization file. For physical protection, containment, surveillance and physical protection measures are presented: Containment measures must prevent the unauthorized or unjustified movements of nuclear material in the framework of the authorized activities; Surveillance measures must guarantee the integrity of the containment, check that no material is exiting by an abnormal channel; Physical protection measures for the materials, the premises and the facilities are intended to protect them against malevolent actions by means of security systems. The Central Security Division has established guidelines to provide guidance to the nuclear materials holders in writing such files. Each holding unit has to establish a 'license and control file' and each CEA site establishes a 'site license and control file

  10. Gonad shielding in diagnostic radiology

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    The use of gonad shielding is an important radiation protection technique, intended to reduce unnecessary x-ray exposure of the gonads of patients from diagnostic x-ray procedures. The types of gonad shields in use are discussed as are the types of diagnostic examinations that should include gonad shielding. It was found that when properly used, most shields provided substantial gonad dose reductions

  11. Health protection and industrial safety. Nuclear power plants

    International Nuclear Information System (INIS)

    1987-03-01

    The standard applies to components of the primary circuit including its auxiliary facilities, and of the secondary circuit of nuclear power plants with pressurized water reactors; to lifting gear and load take-ups for the transport of nuclear fuel and primary circuit components; to elevators within the containment, electrical installations, and piping and valves of radiation protection monitoring equipment. Part 1 defines the terms and specifies engineered safety requirements

  12. Burst protected nuclear reactor plant with PWR

    International Nuclear Information System (INIS)

    Harand, E.; Michel, E.

    1978-01-01

    In the PWR, several integrated components from the steam raising unit and the main coolant pump are grouped around the reactor pressure vessel in a multiloop circuit and in a vertical arrangement. For safety reasons all primary circuit components and pipelines are situated in burst protection covers. To reduce the area of the plant straight tube steam raising units with forced circulation are used as steam raising units. The boiler pumps are connected to the vertical tubes and to the pressure vessel via double pipelines made as twin chamber pipes. (DG) [de

  13. Radiological protection system in the era of nuclear renaissance expectation for development of radiological protection system

    International Nuclear Information System (INIS)

    Toyomatsu, Hideki

    2008-01-01

    The current radiological protection system, which was established mainly by the ICRP and UNSCEAR, has contributed to the prevention of potential radiological health hazards, and has been a fundamental concept during the development of nuclear energy. Through a detailed discussion regarding the new ICRP recommendations, the world nuclear industry has reached a consensus that the current radiological protection system keeps its integrity in principle although it involves some remaining issues, such as the disposal of radioactive waste. In order to maximize the advantages of nuclear energy while keeping the integrity of radiological protection system, it is essential to address the characteristics of radiation, which is specific to nuclear energy, so that nuclear energy can coexist with other energy sources. The three basic principles of radiological protection (i.e., justification, optimization and dose limits), which were completed in the 1990 recommendations of ICRP, should be retained as the basic concepts for the future radiological protection system in order to maintain the continuity and consistency of the radiological protection system. The radiological protection system can be furthermore developed only by combining the above three principles with best practices extracted from utilities' field experience. The significant reduction of radiation exposures received by members of the public and radiation workers in the field has resulted from the efforts by the world utilities to achieve the optimization. In order to correctly apply the theory to the work practices, it is essential to see how the theory is practically used in the field. Such a process should be also emphasized in the revision work of the IAEA Basic Safety Standards (BSS), which is currently under progress. Integrating the theory in the work practices is the key to the true development of nuclear renaissance, which could lead to the establishment of the nuclear safety regime. (author)

  14. Shielding practice

    International Nuclear Information System (INIS)

    Sauermann, P.F.

    1985-08-01

    The basis of shielding practice against external irradiation is shown in a simple way. For most sources of radiation (point sources) occurring in shielding practice, the basic data are given, mainly in the form of tables, which are required to solve the shielding problems. The application of these data is explained and discussed using practical examples. Thickness of shielding panes of glove boxes for α and β radiation; shielding of sealed γ-radiography sources; shielding of a Co-60 radiation source, and of the manipulator panels for hot cells; damping factors for γ radiation and neutrons; shielding of fast and thermal neutrons, and of bremsstrahlung (X-ray tubes, Kr-85 pressure gas cylinders, 42 MeV betatrons, 20 MeV linacs); two-fold shielding (lead glass windows for hot cells, 14 MeV neutron generators); shielding against scattered radiation. (orig./HP) [de

  15. Spin-orbit ZORA and four-component Dirac-Coulomb estimation of relativistic corrections to isotropic nuclear shieldings and chemical shifts of noble gas dimers.

    Science.gov (United States)

    Jankowska, Marzena; Kupka, Teobald; Stobiński, Leszek; Faber, Rasmus; Lacerda, Evanildo G; Sauer, Stephan P A

    2016-02-05

    Hartree-Fock and density functional theory with the hybrid B3LYP and general gradient KT2 exchange-correlation functionals were used for nonrelativistic and relativistic nuclear magnetic shielding calculations of helium, neon, argon, krypton, and xenon dimers and free atoms. Relativistic corrections were calculated with the scalar and spin-orbit zeroth-order regular approximation Hamiltonian in combination with the large Slater-type basis set QZ4P as well as with the four-component Dirac-Coulomb Hamiltonian using Dyall's acv4z basis sets. The relativistic corrections to the nuclear magnetic shieldings and chemical shifts are combined with nonrelativistic coupled cluster singles and doubles with noniterative triple excitations [CCSD(T)] calculations using the very large polarization-consistent basis sets aug-pcSseg-4 for He, Ne and Ar, aug-pcSseg-3 for Kr, and the AQZP basis set for Xe. For the dimers also, zero-point vibrational (ZPV) corrections are obtained at the CCSD(T) level with the same basis sets were added. Best estimates of the dimer chemical shifts are generated from these nuclear magnetic shieldings and the relative importance of electron correlation, ZPV, and relativistic corrections for the shieldings and chemical shifts is analyzed. © 2015 Wiley Periodicals, Inc.

  16. Nuclear Accidents Intervention Levels for Protection of the Public

    International Nuclear Information System (INIS)

    1989-01-01

    The impact of the 1986 Chernobyl accident called attention to the need to improve international harmonization of the principles and criteria for the protection of the public in the event of a nuclear accident. This report provides observations and guidance related to the harmonization of radiological protection criteria, and is intended to be of use to national authorities and international organizations examining the issue of emergency response planning and intervention levels

  17. [Safeguards for the physical protection of nuclear materials and facilities

    International Nuclear Information System (INIS)

    Jones, O.E.

    1975-01-01

    Testimony is given on the subject of safeguards for the physical protection of nuclear materials and facilities, particularly during transportation. The ERDA nation-wide safe-secure transportation system and the Safe-Secure Trailer are described. The nationwide ERDA voice communication system is also described. Development of hardware and systems is discussed. The use of adversary simulation for evaluating protection systems is mentioned

  18. Distributed systems for the protection of nuclear stations

    International Nuclear Information System (INIS)

    Jover, P.

    1980-01-01

    The advantages of distributed control systems usually mentioned are improved exploitation, cost reduction, and adaptation to changes in technology. These advantages are obviously very interesting for nuclear power plant applications, and many such systems have been proposed. This note comments on the application of the distributed system concept to protection systems - what should be distributed - and closes with a brief description of a protection system based on microprocessors for pressurized water stations being built in France. (auth) [fr

  19. Meeting the Grand Challenge of Protecting Astronaut's Health: Electrostatic Active Space Radiation Shielding for Deep Space Missions

    Data.gov (United States)

    National Aeronautics and Space Administration — This study will seek to test and validate an electrostatic gossamer structure to provide radiation shielding. It will provide guidelines for energy requirements,...

  20. Protecting agriculture against nuclear radiations: conception and measures

    International Nuclear Information System (INIS)

    Lehmann Hans-Joerg

    1997-01-01

    In case of atomic and chemical (AC) accident or attacks the agriculture is severely affected. This became clearly after the Chernobyl disaster, after which the authorities mobilized and increased the efforts to protect the agriculture. In Switzerland the Federal Commission for AC protection has undertaken the necessary actions in collaboration with the Federal Office for Agriculture. The protection of agriculture against radioactive fallout has many aspects. One of these concerns the requirement of informing farmers with all the necessary instruction to ensure the protection of rural population and animals, foods and forages, to make them able to take essential protection measures without exterior assistance, and to provide the agriculture buildings with simple and durable tools necessary in case of emergency intervention. To implement these requirements on Confederation level educational programs were developed to instruct agriculture agents and advisors on basic notions of radioactivity and radiation protection. These programs are thought to make the farmer aware with the implications of nuclear chemical and nuclear menace and the measures of protecting its enterprise by own means. Special instructions are to be applied by the enterprise chiefs to ensure first that the personnel protection is the top priority and then how to minimize and limit the damage produced by the radiation accident

  1. Environment Protection (Nuclear Codes) Act 1978, No. 32

    International Nuclear Information System (INIS)

    1978-01-01

    The purpose of this Act is to make provision for protecting the health and safety of the people of Australia, and the environment from possible harmful effects associated with nuclear activities. The competent Federal Minister, after consultation with the appropriate Minister of each State, may from time to time arrange for the formulation of codes of practice for regulating and controlling nuclear activities. Also, the Governor-General may authorize by order a Minister to take such action as is necessary to control and eliminate hazards to the health and safety of persons, or the environment, resulting from a nuclear activity. (NEA) [fr

  2. Security Culture in Physical Protection of Nuclear Material and Facility

    International Nuclear Information System (INIS)

    Susyanta-Widyatmaka; Koraag, Venuesiana-Dewi; Taswanda-Taryo

    2005-01-01

    In nuclear related field, there are three different cultures: safety, safeguards and security culture. Safety culture has established mostly in nuclear industries, meanwhile safeguards and security culture are relatively new and still developing. The latter is intended to improve the physical protection of material and nuclear facility. This paper describes concept, properties and factors affecting security culture and interactions among these cultures. The analysis indicates that anybody involving in nuclear material and facility should have strong commitment and awareness of such culture to establish it. It is concluded that the assessment of security culture outlined in this paper is still preliminary for developing and conduction rigorous security culture implemented in a much more complex facility such as nuclear power plant

  3. Large-scale experiment with laying shielding concrete at Dukovany nuclear power plant

    International Nuclear Information System (INIS)

    Hoenig, A.; Svoboda, R.; Rosa, J.

    1984-01-01

    In some places the concrete walls of the biological shielding are so thin that it is not possible to control the density of the deposited concrete. An experiment was therefore carried out which was to demonstrate that concrete may be deposited by sinking through concrete tubes or by a concrete pump from a height of 8 metres. Two test walls A and B were concreted using the non-standardized method and the third wall was used as the standard. The following tests were conducted on the two non-standardized walls: test of miscibility of extra-heavy concrete, ultrasonic test of homogeneity, and samples were taken for tests of density. Density was determined radiometrically using a narrow gamma beam. Statistical evaluation of the results showed that the homogeneity of density of the concrete was the best in the standard wall, in walls A and B the variation coefficient did not exceed 8 per mille. An exception was made to the rule and concrete with a max. 16 mm grain size was deposited from the height of 8 m on condition of strict observance of production technology. (J.P.)

  4. Shielding in experimental areas

    International Nuclear Information System (INIS)

    Stevens, A.; Tarnopolsky, G.; Thorndike, A.; White, S.

    1979-01-01

    The amount of shielding necessary to protect experimental detectors from various sources of background radiation is discussed. As illustrated an experiment has line of sight to sources extending approx. 90 m upstream from the intersection point. Packing a significant fraction of this space with shielding blocks would in general be unacceptable because primary access to the ring tunnel is from the experimental halls. (1) From basic machine design considerations and the inherent necessity to protect superconducting magnets it is expected that experimental areas in general will be cleaner than at any existing accelerator. (2) Even so, it will likely be necessary to have some shielding blocks available to protect experimental apparatus, and it may well be necessary to have a large amount of shielding available in the WAH. (3) Scraping will likely have some influence on all halls, and retractable apparatus may sometimes be necessary. (4) If access to any tunnel is needed to replace a magnet, one has 96 h (4 days) available to move shielding away to permit access without additional downtime. This (the amount of shielding one can shuffle about in 96 h) is a reasonable upper limit to shielding necessary in a hall

  5. Nuclear Power Plant Fire Protection Research Program

    International Nuclear Information System (INIS)

    Datta, A.

    1985-07-01

    The goal is to develop test data and analytical capabilities to support the evaluation of: (1) the contribution of fires to the risk from nuclear power plants; (2) the effects of fires on control room equipment and operations; and (3) the effects of actuation of fire suppression systems on safety equipment. A range of fire sources will be characterized with respect to their energy and mass evolution, including smoke, corrosion products, and electrically conductive products of combustion. An analytical method for determining the environment resulting from fire will be developed. This method will account for the source characteristics, the suppression action following detection of the fire, and certain parameters specific to the plant enclosure in which the fire originates, such as the geometry of the enclosure and the ventilation rate. The developing local environment in the vicinity of safety-related equipment will be expressed in terms of temperatures, temperature rise rates, heat fluxes, and moisture and certain species content. The response of certain safe shutdown equipment and components to the environmental conditions will be studied. The objective will be to determine the limits of environmental conditions that a component may be exposed to without impairment of its ability to function

  6. Chapter No.5. Nuclear materials and physical protection of nuclear installations

    International Nuclear Information System (INIS)

    2002-01-01

    The State System of Accounting for and Control of Nuclear Material (SSAC) is based on requirements resulting from the Safeguards Agreement between the Government of the Slovak Republic and the IAEA. UJD performs this activity according to the 'Atomic Act' and relevant decree. The purpose of the SSAC is also to prevent unauthorised use of nuclear materials, to detect loses of nuclear materials and provide information that could lead to the recovery of missing material. The main part of nuclear materials under jurisdiction of the Slovak Republic is located at NPP Jaslovske Bohunice, NPP Mochovce and at interim storage in Jaslovske Bohunice. Even though that there are located more then 99% of nuclear materials in these nuclear facilities, there are not any significant problems with their accountancy and control due to very simply identification of accountancy units - fuel assemblies, and due to stability of legal subjects responsible for operation and for keeping of information continuity, which is necessary for fulfilling requirements of the Agreement. The nuclear material located outside nuclear facilities is a special category. There are 81 such subjects of different types and orientations on the territory of the Slovak Republic. These subjects use mainly depleted uranium as a shielding and small quantity of natural uranium, low enrichment uranium and thorium for experimental purposes and education. Frequent changes of these subjects, their transformations into the other subjects, extinction and very high fluctuation of employees causes loss of information about nuclear materials and creates problems with fulfilling requirements resulting from the Agreement. In 2001, the UJD carried out 51 inspections of nuclear materials, of which 31 inspections were performed at nuclear installations in co-operation with the IAEA inspectors. No discrepancies concerning the management of nuclear materials were found out during inspections and safeguards goals in year 2001 were

  7. Durability and shielding performance of borated Ceramicrete coatings in beta and gamma radiation fields

    Energy Technology Data Exchange (ETDEWEB)

    Wagh, Arun S., E-mail: asw@anl.gov [Environmental Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Sayenko, S.Yu.; Dovbnya, A.N.; Shkuropatenko, V.A.; Tarasov, R.V.; Rybka, A.V.; Zakharchenko, A.A. [National Science Center, Kharkov Institute of Physics and Technology, Kharkov (Ukraine)

    2015-07-15

    Highlights: • It incorporates all suggestions by the reviewers. • Explanation to each new term is provided and suitable references are given. • Sample identities have been streamlined by revising the text and the tables. • Some figures have been redrawn. - Abstract: Ceramicrete™, a chemically bonded phosphate ceramic, was developed for nuclear waste immobilization and nuclear radiation shielding. Ceramicrete products are fabricated by an acid–base reaction between magnesium oxide and mono potassium phosphate. Fillers are used to impart desired properties to the product. Ceramicrete’s tailored compositions have resulted in several commercial structural products, including corrosion- and fire-protection coatings. Their borated version, called Borobond™, has been studied for its neutron shielding capabilities and is being used in structures built for storage of nuclear materials. This investigation assesses the durability and shielding performance of borated Ceramicrete coatings when exposed to gamma and beta radiations to predict the composition needed for optimal shielding performance in a realistic nuclear radiation field. Investigations were conducted using experimental data coupled with predictive Monte Carlo computer model. The results show that it is possible to produce products for simultaneous shielding of all three types of nuclear radiations, viz., neutrons, gamma-, and beta-rays. Additionally, because sprayable Ceramicrete coatings exhibit excellent corrosion- and fire-protection characteristics on steel, this research also establishes an opportunity to produce thick coatings to enhance the shielding performance of corrosion and fire protection coatings for use in high radiation environment in nuclear industry.

  8. Oscillatory vapour shielding of liquid metal walls in nuclear fusion devices

    NARCIS (Netherlands)

    van Eden, G.G.; Kvon, V.; Van De Sanden, M.C.M.; Morgan, T.W.

    2017-01-01

    Providing an efficacious plasma facing surface between the extreme plasma heat exhaust and the structural materials of nuclear fusion devices is a major challenge on the road to electricity production by fusion power plants. The performance of solid plasma facing surfaces may become critically

  9. Fire protection guidelines for nuclear power plants, June 1976

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Guidelines acceptable to the NRC staff for implementing in the development of a fire protection program for nuclear power plants. The purpose of the fire protection program is to ensure the capability to shut down the reactor and maintain it in a safe shutdown condition and to minimize radioactive releases to the environment in the event of a fire. If designs or methods different from the guidelines presented herein are used, they must provide fire protection comparable to that recommended in the guidelines. Suitable bases and justification should be provided for alternative approaches to establish acceptable implementation of General Design Criterion 3

  10. Considerations on radiation protection and accidents in nuclear medicine

    International Nuclear Information System (INIS)

    Lima, Carla Flavia de; Avelar, Artur Canella; Campos, Tarcisio P.R.

    2001-01-01

    The present study presents the radiation protection in the services of nuclear medicine in relation to the design of the services, manipulation of sources, cares with the patient, accomplishment of procedures and definition of accidents and incidents; besides approaching the CNEN requirements

  11. Radiation protection courses in the Milan Copic Nuclear Training Centre

    International Nuclear Information System (INIS)

    Kozelj, M.; Stritar, A.

    1998-01-01

    We have briefly described the legal framework for the radiation protection training in Slovenia. The history of that activity at the Milan Copic Nuclear Training Center in Ljubljana is than described with the detailed description and summary of all performed courses.(author)

  12. Optimization of radiological protection in Spanish nuclear power plants

    International Nuclear Information System (INIS)

    O'Donnell, P.; Amor, I.; Butragueno, J.L.

    1997-01-01

    Optimizing the radiological protection of occupationally exposed nuclear power plant workers has become one further item in what is called the safety culture. Spanish facilities are implementing programme with this in mind, grounded on a personal motivation policy with the backing of a suitable organizational structure. (Author)

  13. Code of practice for radiation protection in nuclear medicine

    International Nuclear Information System (INIS)

    Hamed, M. I.

    2010-05-01

    In aim of this study was to develop a draft for a new code practice for radiation protection in nuclear medicine that meets the current relevant international recommendation. The draft includes the following main fields: methods of radiation protection for workers, patients and public. Also, the principles of safe design of nuclear medicine departments, quality assurance program, proper manipulation of radiation sources including radioactive waste and emergency preparedness and response. The practical part of this study includes inspections of three nuclear medicine departments available in Sudan so as to assess the degree of compliance of those departments with what is stated in this code. The inspection missions have been conducted using a checklist that addresses all items that may affect radiation raincoat issues in addition to per formin area radiation monitoring around the installation of the radioactive sources. The results of this revealed that most of the departments do not have effective radiation protection program which in turn could lead to unnecessary exposure to patients, public and workers. Finally, some recommendations are given that - if implemented - could improve the status of radiation protection in nuclear medicine department. (Author)

  14. Radiation safety and protection on the nuclear power plants

    International Nuclear Information System (INIS)

    Nosovskij, A.V.; Bogorad, V.I.; Vasil'chenko, V.N.; Klyuchnikov, A.A.; Litvinskaya, T.V.; Slepchenko, A.Yu.

    2008-01-01

    The main issues of the radiation safety and protection provision on the nuclear power plants are considered in this monograph. The description of the basic sources of the radiation danger on NPPs, the principles, the methods and the means of the safety and radiation monitoring provision are shown. The special attention is paid to the issues of the ionizing radiation regulation

  15. Convention on the physical protection of nuclear material

    International Nuclear Information System (INIS)

    1991-09-01

    The document refers to the Convention on the Physical Protection of Nuclear Material (IAEA-INFCIRC-274). Part I contains the status list as of September 6, 1991; Part II contains the texts of reservations/declarations made upon expressing consent to be bound; Part III contains the texts of reservations/declarations made upon signature

  16. The declaration regime: An efficient tool to improve control and protection of nuclear materials in France

    International Nuclear Information System (INIS)

    Pillette-Cousin, L.

    2001-01-01

    Full text: The French Government set up a national safeguards system under the authority of the Ministry for Industry to control nuclear materials within national boundaries and to ensure physical protection for nuclear materials, even for the small quantities held by users in industrial, medical and research areas. The main nuclear materials detained by small owners are depleted uranium and thorium. These materials are present in manufactured equipment (radiation shielding in industrial gammagraphy and radiotherapy, collimation devices and other accessories) which are used or unused, which may be damaged or left as scraps. The French protection and control system of nuclear materials is an original system based on detailed and comprehensive regulations, taking into account in a specific way the small users of nuclear materials. The decree no. 81-512 of 12 May 1981 establishes three different regimes: licensing, declaration and exemption, according to the nature and quantity of nuclear materials involved. Typically, the declaration regime applies to quantities of depleted uranium or thorium, greater than 1 kg and lower than 500 kg. The Order of 14 March 1984 sets the requirements related to the control and physical protection of nuclear materials in the frame of the declaration regime. A declaration must be established every year by the operator and sent to the IPSN, acting as technical support body of the national authority. This declaration provides the stock of all nuclear materials held by the operator and stock variations occurred during the previous year, including the identification of senders and receivers. Before fulfilling its annual declaration, the operator must carry out a physical inventory of all nuclear material, both used and unused. The declaration also describes the main features concerning facility layout related to surveillance and physical protection of materials. With respect to physical protection requirements, nuclear materials should be

  17. Fire protection maintenance at Browns Ferry Nuclear Plant

    International Nuclear Information System (INIS)

    Kern, J.R.

    1989-01-01

    This paper describes two approaches to staffing and organizing a fire protection maintenance group. Both have been used at Browns Ferry Nuclear Plant. One takes traditional craft functions and relocates them from the plant maintenance department to the fire protection section. The other expands the role to include response to fire, medical, and hazardous material emergencies. Both approaches remove the fire protection supervisor from a purely staff role, and involve him/her in direct-line management functions. This results in improved technical direction to the craftsmen, improved quality of the work performed, and improved craft morale. It also assures the fire protection supervisor of much more detailed knowledge of the overall status of the fire protection systems

  18. War protected underground siting of nuclear power plants -a summary

    International Nuclear Information System (INIS)

    1974-06-01

    In connection with studies concerning the need of war protected nuclear power production the technical and economical conditions with war protection of nuclear power plants have been studied within CDL. Comprehensively one have shown that no technical construction obstacles for siting a nuclear power plant underground exist that the additional costs for underground siting with price level mid 1973 are some 175-250 MSwCr (In today's price level 250 MSwCr will probably correspond to some 300 MSwCr per unit) and that the construction time is some one year longer than for an above ground plant. A study ought to examine more closely the consequences of underground siting from a radiological point of view and what demands on that occasion ought to be put on the technical design. (author)

  19. Radiation protection for population in case of nuclear weapon terrorism

    International Nuclear Information System (INIS)

    Takada, Jun

    2004-01-01

    A radiation disaster was predicted in case of 1 kt nuclear weapon terrorism on the surface. Despite small size, serious radiation exposure became clear in a range more than 10 km that can't be by an aerial explosion. This kind of exposure comes from radioactive fallout of fission products, not from direct nuclear radiation. This spreads to a lee area. More than 1,000,000 population receive a serious dose including fatal dose if the nuclear disaster occurs in Tokyo is expected. If adequate radiation protection applies to the population, 70% of victim may be saved. A method to be effective as this kind of protection is escape from a danger zone by the subway after more than one hour sheltering in a concrete building. (author)

  20. Electromagnetic shielding

    International Nuclear Information System (INIS)

    Tzeng, Wen-Shian V.

    1991-01-01

    Electromagnetic interference (EMI) shielding materials are well known in the art in forms such as gaskets, caulking compounds, adhesives, coatings and the like for a variety of EMI shielding purposes. In the past, where high shielding performance is necessary, EMI shielding has tended to use silver particles or silver coated copper particles dispersed in a resin binder. More recently, aluminum core silver coated particles have been used to reduce costs while maintaining good electrical and physical properties. (author). 8 figs

  1. 78 FR 55765 - Compensatory and Alternative Regulatory Measures for Nuclear Power Plant Fire Protection (CARMEN...

    Science.gov (United States)

    2013-09-11

    ... Nuclear Power Plant Fire Protection (CARMEN-FIRE) AGENCY: Nuclear Regulatory Commission. ACTION: Draft..., ``Compensatory and Alternative Regulatory Measures for Nuclear Power Plant Fire Protection (CARMEN-FIRE).'' In... caused by impaired fire protection features at nuclear power plants. The report documents the history of...

  2. 78 FR 45573 - Compensatory and Alternative Regulatory Measures for Nuclear Power Plant Fire Protection (CARMEN...

    Science.gov (United States)

    2013-07-29

    ... Nuclear Power Plant Fire Protection (CARMEN-FIRE) AGENCY: Nuclear Regulatory Commission. ACTION: Notice of... Nuclear Power Plant Fire Protection (CARMEN-FIRE), Draft Report for Comment.'' DATES: Comments on this... caused by impaired fire protection features at nuclear power plants. The report documents the history of...

  3. Regulatory inspections in nuclear plants in the field of radiation protection

    International Nuclear Information System (INIS)

    Hort, M.; Fuchsova, D.

    2014-01-01

    State Office for Nuclear Safety executes state administration and performs inspections at peaceful use of nuclear energy and ionizing radiation in the field of radiation protection and nuclear safety. Inspections on radiation protection at nuclear power plants are secured by inspectors of the Department of Radiation Protection in Fuel Cycle, who work at the Regional centre Brno and Ceske Budejovice. (authors)

  4. Protection of nuclear power plants against external events

    International Nuclear Information System (INIS)

    Suetterlin, L.

    1978-01-01

    The different aspects for the selection of external events to be accounted for in designing nuclear power plants and in defining load assumptions are illustrated: 1) In case of earthquake the severest possible events according to the state of science and technology are assumed. 2) For events where it is not or only to a certain extent possible to apply this method, e.g. in the load case airplane crash, load assumptions are defined in a combined probabilitic-deterministic way. By the example of plant protection, it is shown that by integrating all measures for protecting against interference of third parties (sabotage) or other external events, optimum protection concepts may be achieved. In all considerations on interference of third parties or other external events, one has to take into account that absolute protection is not possible. Nevertheless, it may be confirmed that nuclear power plants not only have a much higher level of protection than other, non-nuclear plants with equal or even higher potential hazard, but also that they meet the requirement not to increase significantly the current risk of society. (orig./HP) [de

  5. Protecting nuclear material and facilities: Is a new approach needed?

    International Nuclear Information System (INIS)

    Steinhausler, F.; Bunn, G.

    2002-01-01

    Full text: The main reason why national physical protection (PP) systems for nuclear and other radioactive material need to be strengthened further is that, after the attacks on the US on 11 September 2001, the threat of dangerous, suicidal radiological and nuclear terrorism can no longer be excluded as a possibility. Existing PP systems were not designed to deal with the threat of suicidal terrorists having the numbers, skills, training, and resources available to the commandos attacking on 11 September. Moreover, there are no mandatory international standards for domestic PP systems for nuclear or radioactive material, and this has produced great variation in protection provided from country to country. IAEA recommended standards, while useful, were not designed with the new terrorist threat in mind. Moreover, they are often not followed in practice. The result is inadequate protection against the new form of terrorism in most countries. The Director General of the IAEA expressed a similar view after 11 September, but achieving a consensus to amend the Convention on the Physical Protection of Nuclear Material (CPPNM) to require specific standards of protection for different amounts and kinds of nuclear material used or stored domestically (not in international transport) has been impossible in the year since 11 September. In the case of radiological materials, a new effort to provide required international standards for protection against the new form of terrorism has not begun. In the summer of 2001, leaders of the G-8 countries agreed to a Global Partnership to prevent the new terrorists from acquiring nuclear and radiological as well as other materials related to weapons of mass destruction. Perhaps in part because of the failure to date to achieve agreement on an effective amendment to the CPPNM, the first principle of this partnership is to strengthen 'multilateral treaties and other instruments whose aim is to prevent the proliferation or illicit

  6. Application of gas shielded arc welding and submerged arc welding for fabrication of nuclear reactor vessels

    International Nuclear Information System (INIS)

    Gehani, M.L.; Rodrigues, W.D.

    1976-01-01

    The remarkable progress made in the development of knowhow and expertise in the manufacture of equipment for nuclear power plants in India is outlined. Some of the specific advances made in the application of higher efficiency weld processes for fabrication of nuclear reactor vessels and the higher level of quality attained are discussed in detail. Modifications and developments in submerged arc, gas tungsten arc and gas metal arc processes for welding of Calandria which have been a highly challenging and rewarding experience are discussed. Future scope for making the gas metal arc process more economical by using various gas-mixes like Agron + Oxygen, Argon + Carbon Dioxide, Argon + Nitrogen (for Copper Alloys) etc., in various proportions are outlined. Quality and dimensional control exercised in these jobs of high precision are highlighted. (K.B.)

  7. Basis for radiation protection of the nuclear worker

    International Nuclear Information System (INIS)

    Guevara, F.A.

    1982-01-01

    A description is given of the standards for protection of persons who work in areas that have a potential for radiation exposure. A review is given of the units of radiation exposure and dose equivalent and of the value of the maximum permissible dose limits for occupational exposure. Federal Regulations and Regulatory Guides for radiation protection are discussed. Average occupational equivalent doses experienced in several operations typical of the United States Nuclear Industry are presented and shown to be significantly lower than the maximum permissible. The concept of maintaining radiation doses to As-Low-As-Reasonably-Achievable is discussed and the practice of imposing engineering and administrative controls to provide effective radiation protection for the nuclear worker is described

  8. The principles of protection against fires in nuclear facilities

    International Nuclear Information System (INIS)

    Dupuy, Ph.; Gupta, O.

    2000-01-01

    Because of the presence of fissile or radioactive materials in nuclear facilities, their protection against fires is different from that of classical industrial installations. 3 priorities have been defined, in importance order: 1) maintaining nuclear safety in order to protect public and environment, 2) protection of workers, and 3) limiting the damages on the installation. The prevention of fires is based on 4 rules: 1) limiting as much as possible the quantity of inflammable materials and imposing a strict control of any use of igniting source, 2) assuring a permanent monitoring of the installation by means of reliable devices able to detect any fire starting, 3) designing the sectorization of the installation in order to keep fire in delimited zones and prevent its extension, and 4) enhancing the efficiency of the fire brigade intervention. (A.C.)

  9. The SGR Multipurpose - Generation IV - Transportable Cogeneration Nuclear Reactor with Innovative Shielding

    International Nuclear Information System (INIS)

    Pahladsingh, R.R.

    2002-01-01

    Deregulation and liberalization are changing the global energy-markets. At the same time innovative technologies are introduced in the electricity industry; often as a requirement from the upcoming Digital Society. Energy solutions for the future are more seen as a mix of energy-sources for generation-, transmission- and distribution energy-services. The Internet Energy-web based 'Virtual' enterprises are coming up and will gradually change our society. It the fast changing world we have to realize that there will be less time to look for the adequate solutions to anticipate on global developments and the way they will influence our own societies. Global population may reach 9 billion people by 2030; this will put tremendous pressure on energy-, water- and food supply in the global economy. It is time to think about some major issues as described below and come up with the right answers. These are needed on very short term to secure a humane global economic growth and the sustainable global environment. The DOE (Department of Energy - USA) has started the Generation IV initiative for the new generation of nuclear reactors that must lead to much better safety, economics and public acceptance the new reactors. The SGR (Simplified Gas-cooled Reactor) is being proposed as a Generation IV modular nuclear reactor, using graphite pebbles as fuel, whereby an attempt has been made to meet all the DOE requirements, to be used for future nuclear reactors. The focus in this paper is on the changing and emerging global energy-markets and shows some relevant criteria to the nuclear industry and how we can anticipate with improved and new designs towards the coming Digital Society. (author)

  10. Implementation of ALARA radiation protection on the ISS through polyethylene shielding augmentation of the Service Module Crew Quarters

    Science.gov (United States)

    Shavers, M. R.; Zapp, N.; Barber, R. E.; Wilson, J. W.; Qualls, G.; Toupes, L.; Ramsey, S.; Vinci, V.; Smith, G.; Cucinotta, F. A.

    2004-01-01

    With 5-7 month long duration missions at 51.6° inclination in Low Earth Orbit, the ionizing radiation levels to which International Space Station (ISS) crewmembers are exposed will be the highest planned occupational exposures in the world. Even with the expectation that regulatory dose limits will not be exceeded during a single tour of duty aboard the ISS, the "as low as reasonably achievable" (ALARA) precept requires that radiological risks be minimized when possible through a dose optimization process. Judicious placement of efficient shielding materials in locations where crewmembers sleep, rest, or work is an important means for implementing ALARA for spaceflight. Polyethylene (C nH n) is a relatively inexpensive, stable, and, with a low atomic number, an effective shielding material that has been certified for use aboard the ISS. Several designs for placement of slabs or walls of polyethylene have been evaluated for radiation exposure reduction in the Crew Quarters (CQ) of the Zvezda (Star) Service Module. Optimization of shield designs relies on accurate characterization of the expected primary and secondary particle environment and modeling of the predicted radiobiological responses of critical organs and tissues. Results of the studies shown herein indicate that 20% or more reduction in equivalent dose to the CQ occupant is achievable. These results suggest that shielding design and risk analysis are necessary measures for reducing long-term radiological risks to ISS inhabitants and for meeting legal ALARA requirements. Verification of shield concepts requires results from specific designs to be compared with onboard dosimetry.

  11. Man as a protective barrier in nuclear power plants

    International Nuclear Information System (INIS)

    Fechner, J.B.

    1980-01-01

    Evaluation of nuclear power plant incidents frequently reveals man as a major element of risk. Yet, in a nuclear power plant man has the function of an important protective barrier, either by maintaining the plant, by detecting and limiting faults or incidents, or by taking proper measures in accidents. This is true despite, or perhaps because of, the high degree of plant automation. For this reason, it is indispensable that a high level of engineered plant safeguards be accompanied by a minimum of faults contributed by human action. This implies that the staff and their working conditions must meet the same stringent safety requirements as the nuclear power plant proper. Reactor manufacturers, nuclear power plant operators and the responsible authorities try to optimize this human contribution. The Federal Ministry of the Interior, through its Special Technical Guidelines and its continuation training measures, occupies an important position in this respect. Further measures and ordinances are being prepared by that Ministry. (orig.) [de

  12. Nuclear Rocket Facility Decommissioning Project: Controlled Explosive Demolition of Neutron-Activated Shield Wall

    International Nuclear Information System (INIS)

    Michael R. Kruzic

    2007-01-01

    Located in Area 25 of the Nevada Test Site (NTS), the Test Cell A (TCA) Facility was used in the early to mid-1960s for the testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program, to further space travel. Nuclear rocket testing resulted in the activation of materials around the reactors and the release of fission products and fuel particles in the immediate area. Identified as Corrective Action Unit 115, the TCA facility was decontaminated and decommissioned (D and D) from December 2004 to July 2005 using the Streamlined Approach for Environmental Restoration (SAFER) process, under the ''Federal Facility Agreement and Consent Order''. The SAFER process allows environmental remediation and facility closure activities (i.e., decommissioning) to occur simultaneously provided technical decisions are made by an experienced decision maker within the site conceptual site model, identified in the Data Quality Objective process. Facility closure involved a seven-step decommissioning strategy. Key lessons learned from the project included: (1) Targeted preliminary investigation activities provided a more solid technical approach, reduced surprises and scope creep, and made the working environment safer for the D and D worker. (2) Early identification of risks and uncertainties provided opportunities for risk management and mitigation planning to address challenges and unanticipated conditions. (3) Team reviews provided an excellent mechanism to consider all aspects of the task, integrated safety into activity performance, increase team unity and ''buy-in'' and promoted innovative and time saving ideas. (4) Development of CED protocols ensured safety and control. (5) The same proven D and D strategy is now being employed on the larger ''sister'' facility, Test Cell C

  13. New aspects regarding to radiation protection in nuclear medicine

    International Nuclear Information System (INIS)

    Shabestani Monfared, A.; Amiri, M.

    2002-01-01

    Introduction and objectives: The society has been concerned about nuclear energy usage and nuclear environment pollution for ages. The necessity of using radiation and its applications in modern life especially in medicine is undeniable. Some interesting properties such as the potential for non-destructive tests, detection simplicity, and penetrability into substances and having reactions with them cause radiation to be known as a useful tool for peace purposes. Nuclear weapons' experiments (1945-1973) and nuclear accidents in Three-Mile Island in USA, Goiania in Brazil and Chernobyl in Ukraine Republic have enhanced man's worries towards nuclear radiation and radioactivity in environment, and founding associations and groups which are against nuclear energy, such as green peace society, can be related with above mentioned concerns. Today, nuclear medicine has rapidly been developed so that in some cases plays a unique role in diagnosis but unfortunately in spite of diagnostic and therapeutic advantages, the term N UCLEAR c an induce worries in patients and society. In this article, base on new documents we intend to show that this worries has no scientific basis. Material and Methods: To produce a realistic view, regarding to radiation protection we used several ways such as natural origin of radiation, high natural background radiation areas' data non-linear dose-effect model, risk versus benefit, use of arbitrary unit for measurement of radiation, radio adaptive response and radiation hormesis. Discussion and conclusion: Harmful effects of radiation on biologic systems has obviously been shown, but most of related documents are based on receiving high doses in nuclear and atomic accidents and explosions and radiation protection regulations are based on this observations. So, it sometimes causes patients are afraid of low doses of radiation in medical diagnostic procedures so that some of them even resist against performing this procedures. Thus, being aware of

  14. Radiation protection during operation of nuclear power plants

    International Nuclear Information System (INIS)

    1983-01-01

    This Guide describes a Radiation Protection Programme for nuclear power plants. It includes: (1) An outline of the basic principles as well as practical aspects of the programme; (2) A description of the responsibilities of the operating organization to establish an effective programme based upon these principles; (3) A description of the administrative and technical measures to establish and implement the programme. This Guide also deals with the operational aspects to be considered by the operating organization in reviewing design in order to facilitate implementation of the Radiation Protection Programme. This Guide covers the requirements for a Radiation Protection Programme for all operational states of the nuclear power plant. It also includes guidelines for handling planned special exposures and for coping with unplanned exposures and contamination of personnel, areas, and equipment. Additional information concerning emergency situations involving releases of radioactive materials is given in Safety Guides 50-SG-O6, ''Preparedness of the Operating Organization (Licensee) for Emergencies at Nuclear Power Plants'', and 50-SG-G6, ''Preparedness of Public Authorities for Emergencies at Nuclear Power Plants''. This Guide covers the principles of dose limitation to site personnel and to the public, but it does not include detailed instructions on the techniques used for the actual measurement and evaluation of the exposures. This Guide does not include detailed instructions on environmental surveys, but it does mention principal steps in environmental monitoring which may be required for confirmation of the acceptability of radioactive discharges

  15. Non-combustible x-ray and nuclear radiation shields with high hydrogen content

    International Nuclear Information System (INIS)

    Hall, W.C.; Peterson, J.M.

    1981-01-01

    A method is described for attenuating radiation, especially neutrons, by intercepting the radiation with a non-combustible, self-supporting system formed of a continuous phase of fire-resistant cementitious material in which is dispersed a discontinuous phase. This discontinuous phase contains hydrogen atoms in the form of combustible organic plastic or resin particles, or inorganic compounds such as hydroxides, hydrides, or ammonium compounds. The continuous phase may be any type of cement, mortar, plaster, clay, or it may be a matrix produced from metallic lead powder and water, which also offers some protection against gamma and x-radiation

  16. Twenty years of Radiology in RP-10 nuclear reactor protection

    International Nuclear Information System (INIS)

    Zapata, Alejandro L.; Ramos, Fernando T.; Arrieta, Rolando W.B.; Vela Mora, Mariano

    2013-01-01

    In this report we present the results about radiation controls during 1990 - 2010, carried out in the Nuclear Reactor RP-10 of the Nuclear Center of Huarangal. These controls and radiological evaluation are of much utility for the radio personnel protection of this one and other reactors, since it allows to compares these variables with respect to the time. From the results obtained in monitoring and radiation controls, we conclude that in no case it has been reached the limits allowed by the Peruvian Regulating Authority. (author)

  17. Radiation protection in connection with the decommissioning of nuclear plants

    International Nuclear Information System (INIS)

    1997-04-01

    This document presents the SSI preliminary views and position concerning the decommissioning of nuclear plants. To prevent the exposure of the decommissioning personnel and the general public to unacceptable levels of radiation and to protect the environment and future generations, it is SSI's task to formulate and issue the necessary terms and regulations with which the reactor licensees must comply during the decommissioning work. The views and principles presented here are the basis of SSI's continued work on guidelines and regulations for the decommissioning of nuclear plants

  18. A study of thermal, structural and shielding safety analysis for dry storage of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Shin, S. H. [Kyungpook Nationl Univ., Daegu (Korea, Republic of)

    1997-03-15

    As a replaced method for MRS, the dry storage has been intensively developed by the advanced countries of nuclear power technology. Currently, the domestic technology for the dry storage is also under development. In the present study, the developed technical standards for USNRC and its operation are summarized. Futhermore, the SAR for VECTRA's NUHOMES satisfied with DOE and NRC's requirements is inversely analyzed and combined with both USNRC's regulatory guide and LLNL's SARS. In the safety analysis of a dry storage, the principal design criteria which identifies the structural and mechanical safety criteria is investigated. Based on the design criteria, hypothetical accident analysis as well as off-normal operation analysis are investigated.

  19. Foam-Reinforced Polymer Matrix Composite Radiation Shields, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — New and innovative lightweight radiation shielding materials are needed to protect humans in future manned exploration vehicles. Radiation shielding materials are...

  20. Application of crime countermeasures for the protection of nuclear materials

    International Nuclear Information System (INIS)

    Bean, C.H.

    1975-01-01

    Federal regulations prepared by the Nuclear Regulatory Commission and published in the Federal Register require licensees to take appropriate action to protect the health and safety of the public from unauthorized use of special nuclear material (SNM), which includes plutonium, uranium-233, and highly enriched uranium. Crime countermeasures for compliance with these regulations are an important part of the guidance that is provided by the NRC's Office of Standards Development. The use of crime countermeasures and protective devices is intended to prevent the unauthorized diversion of material and to aid in the detection of diversion should it be attempted. Plant and equipment designs should incorporate both electronic and physical security measures for protection of SNM. This applies to facilities and equipment for reprocessing, fabrication, and transportation of SNM. The protection systems include physical barriers, access controls, intrusion detection devices, surveillance devices, central alarm stations, communications, and response capability. Acceptable security measures and devices applicable to protected areas, material access areas, vital areas, vital equipment, and transportation vehicles have been presented in Regulatory Guides. (U.S.)

  1. Design aspects of radiation protection for nuclear power plants

    International Nuclear Information System (INIS)

    1985-01-01

    This Safety Guide deals with the provisions to be made in the design of thermal neutron reactor power plants to protect site personnel and the public from undue exposure to ionizing radiation during operational states and accident conditions. The effective radiation protection is a combination of good design, high quality construction and proper operation. The document gives guidance on how to satisfy the objectives contained in Subsection 2.2 and Section 9 of the Code of Practice on Design for Safety of Nuclear Power Plants

  2. Some problems concerning the radiation protection in nuclear power stations

    International Nuclear Information System (INIS)

    Bozoky, L.

    1977-01-01

    The appearance and fast spreading of the nuclear power stations raised new and difficult questions in connection with the theoretical bases of radiation protection. The new standpoint of the International Commission on Radiological Protection is that both the workers at a pile and the inhabitants take less risk because of ionizing radiation than they usually take in everyday life. The maximum dose which can be permitted remained 5 rem/year for those who professionally deal with ionizing radiation and 0.5 rem/year for the groups in special situation. (V.N.)

  3. Estimation of isotropic nuclear magnetic shieldings in the CCSD(T) and MP2 complete basis set limit using affordable correlation calculations

    DEFF Research Database (Denmark)

    Kupka, Teobald; Stachów, Michal; Kaminsky, Jakub

    2013-01-01

    , estimated from calculations with the family of polarizationconsistent pcS-n basis sets is reported. This dependence was also supported by inspection of profiles of deviation between CBS estimated nuclear shieldings and obtained with significantly smaller basis sets pcS-2 and aug-cc-pVTZ-J for the selected......A linear correlation between isotropic nuclear magnetic shielding constants for seven model molecules (CH2O, H2O, HF, F2, HCN, SiH4 and H2S) calculated with 37 methods (34 density functionals, RHF, MP2 and CCSD(T) ), with affordable pcS-2 basis set and corresponding complete basis set results...... set of 37 calculation methods. It was possible to formulate a practical approach of estimating the values of isotropic nuclear magnetic shielding constants at the CCSD(T)/CBS and MP2/CBS levels from affordable CCSD(T)/pcS-2, MP2/pcS-2 and DFT/CBS calculations with pcS-n basis sets. The proposed method...

  4. Shielding plugs

    International Nuclear Information System (INIS)

    Makishima, Kenji.

    1986-01-01

    Purpose: In shielding plugs of an LMFBR type reactor, to restrain natural convection of heat in an annular space between a thermal shield layer and a shield shell, to prevent the lowering of heat-insulation performance, and to alleviate a thermal stress in a reactor container and the shield shell. Constitution: A ring-like leaf spring split in the direction of height is disposed in an annular space between a thermal shield layer and a shield shell. In consequence, the space is partitioned in the direction of height and, therefore, if axial temperature conditions and space width are the same and the space is low, the natural convection is hard to occur. Thus the rise of upper surface temperature of the shielding plugs can prevent the lowering of the heat insulation performance which will result in the increment of shielding plug cooling capacity, thereby improving reliability. In the meantime, since there is mounted an earthquake-resisting support, the thermal shield layer will move for a slight gap in case of an earthquake, being supported by the earthquake-resisting support, and the movement of the thermal shield layer is restricted, thereby maintaining integrity without increasing the stroke of the ring-like spring. (Kawakami, Y.)

  5. Structural response of nuclear containment shield buildings with unanticipated construction openings

    Science.gov (United States)

    Mac Namara, Sinead Caitriona

    As Nuclear Power Plants age many require steam generator replacement. There is a nickel alloy in the steam generator tubes that is susceptible to stress cracking and although these cracks can be sealed the generator becomes uneconomical without 10%-15% of the tubes. The steam generator in a typical nuclear power plant is housed in the containment structure next to the reactor. The equipment hatch is not big enough to facilitate steam generator replacement, thus construction openings in the dome of the containment structure are required. To date the structural consequences of construction openings in the dome have not been examined. This thesis examines the effects of such openings. The prototype concrete dome is made up of a 2 ft thick dome atop 3 ft thick and 170 ft high cylindrical walls (radius 65.5 ft) with a tension ring 15 ft high and 8 ft thick in between. The dome of the building is cast in two layers; a lower 9 inch layer that serves as the formwork for an upper 15 inch layer. The weight of the dome is carried in axial compression along the hoops and meridians of the dome. The first finite element model uses shell elements and considers two limiting load cases; where the two layers act as one, and where the lower layer carries the weight of both. The openings interrupt the hoops and meridians and the weight of the dome must be redistributed around the openings. Without openings, the stresses due to dead load in the structure are very low when compared to the material strength. The impact of the openings is increased compression stresses near the opening. The maximum stresses are approximately four times larger than in the original structure. These results are confirmed by the second model which is made from layers of solid elements. This model shows a significant difference between the compression on the top surface of the dome, in the affected areas, and that on the bottom surface, leading to shear stresses. These shear stresses are largest around the

  6. to control the nuclear safety and the radiation protection

    International Nuclear Information System (INIS)

    Lacoste, A.C.; Bordarier, Ph.; Saint-Raymond, Ph.; Repussard, J.; Gouze, J.R.; Degos, L.; Massart, S.; Wiroth, P.; Thezee, Ch.; Petit, G.; Cahen, B.; Hubert, I.; Wiroth, P.; Thezee, Ch.; Petit, G.; Kaufer, B.; Taniguchi, T.; Revol, H.

    2005-01-01

    Publishing this dossier, the aim is to present the principles and the variety of issues linked to nuclear safety and radiation protection supervision, and the main strategic choices made to use efficiently and effectively A.S.N. supervision means. A.S.N. is responsible for nuclear safety and radiation protection supervision. A.S.N. has to be itself evaluated and supervised by external bodies. The Parliament Office for Evaluation of Scientific and Technological Options (O.P.E.C.S.T.) supervises it; the foreign peers watch and A.S.N. has to be the object of an international audit conducted by its peers under the leadership of I.A.E.A. by the beginning of 2007. (N.C.)

  7. Reactor control and protection of full scope simulator for Qinshan 300 MW Nuclear Power Unit

    International Nuclear Information System (INIS)

    Zhu Jinping; Sun Jiliang

    1996-01-01

    The control and protection simulation of Qinshan 300 MW Nuclear Power Unit, including the nuclear control, the pressurizer pressure control, the pressurizer level control, the rod control, the reactor shutdown protection and engineered safety feature etc are briefly introduced

  8. Strategy and system of fire protection at Guangdong Daya Bay Nuclear Power Plant

    International Nuclear Information System (INIS)

    Zhou Weihong

    1999-12-01

    The fire protection is an important safety issue of nuclear power utilities. The author depicts the strategy and management system of fire protection implemented successfully at Guangdong Daya Bay Nuclear Power Plant of China

  9. Dictionary of radiation protection, radiobiology and nuclear medicine. English-German-French-Russian. Strahlenschutz, Strahlenbiologie, Nuklearmedizin. Englisch-Deutsch-Franzoesisch-Russisch

    Energy Technology Data Exchange (ETDEWEB)

    Sube, R

    1985-01-01

    This multilingual dictionary covers the subject fields of radiation protection, radiobiology, and nuclear medicine with about 12,000 terms in each language. All terms are supplemented by one or more abbreviations of 22 special branches to assure the use of the very relevant terms. Special branches listed are for instance decontamination, dosimetry, atomic legislation, radiation detectors, radiography (medical), radiotherapy, safeguards, shielding, tansportation and storage. The terminology used in the International Nuclear Information System (INIS) of the IAEA has been completely taken into account.

  10. Competent person for radiation protection. Practical radiation protection for base nuclear installations and installations classified for the environment protection

    International Nuclear Information System (INIS)

    Pin, A.; Perez, S.; Videcoq, J.; Ammerich, M.

    2008-01-01

    This book corresponds to the practical module devoted to the base nuclear installations and to the installations classified for the environment protection, that is to say the permanent nuclear installations susceptible to present risks for the public, environment or workers. Complied with the legislation that stipulates this module must allow to apply the acquired theoretical training to practical situations of work, it includes seven chapters as follow: generalities on access conditions in regulated areas of nuclear installation,s or installations classified for environment protection and clothing against contamination; use of control devices and management of damaged situations; methodology of working place studies, completed by the application to a real case of a study on an intervention on a containment wall; a part entitled 'take stock of the situation' ends every chapter and proposes to the reader to check its understanding and acquisition of treated knowledge. (N.C.)

  11. Effect of nuclear shielding in collision of positive charged helium ions with helium atoms

    Science.gov (United States)

    Ghavaminia, Hoda; Ghavaminia, Shirin

    2018-03-01

    Differential in angle and absolute cross sections in energy of the scattered particles are obtained for single charge exchange in ^3He^+-^4He collisions by means of the four body boundary-corrected first Born approximation (CB1-4B). The quantum-mechanical post and prior transition amplitudes are derived in terms of two-dimensional real integrals in the case of the prior form and five-dimensional quadratures for the post form. The effect of the dynamic electron correlation through the complete perturbation potential and the nuclear-screening influence of the passive electrons on the electron capture process is investigated. The results obtained in the CB1-4B method are compared with the available experimental data. For differential cross sections, the present results are in better agreement with experimental data than other theoretical data at extreme forward scattering angles. The integral cross sections are in excellent agreement with the experiment. Also, total cross sections for single electron capture, has been investigated using the classical trajectory Monte Carlo method. The present calculated results are found to be in an excellent agreement with the experimental data.

  12. Some current aspects of the staff protection in nuclear medicine

    International Nuclear Information System (INIS)

    Hudzietzova, J.; Sabol, J.

    2012-01-01

    The paper discusses some specific questions of irradiation of workers in various professions on typical nuclear medicine workplace in connection with the performance of their specific tasks. There are also given the results of the monitoring of individual doses, which show the significant differences in exposure of personnel groups. Special attention is paid to the protection of workers and others who come into contact with patients who received high-level radiopharmaceuticals for therapeutic purposes. (authors)

  13. Convention on the physical protection of nuclear materials

    International Nuclear Information System (INIS)

    1997-01-01

    The document refers to the Convention on the Physical Protection of Nuclear Material (IAEA-INFCIRC-274), including in Part I the status list of signature, ratification, acceptance, approval, accession or succession by States or organizations as of 31 December 1996, in Part II the texts of reservations/declarations made upon or following expressing consent to be bound, and in Part III the texts of reservations/declarations made upon signature

  14. Convention on the physical protection of nuclear material

    International Nuclear Information System (INIS)

    1990-08-01

    The document refers to the Convention on the Physical Protection of Nuclear Material (INFCIRC/274). Part I contains reservations/declarations made upon or following signature and Part II contains reservations/declarations made upon or following deposit of instrument of consent to be bound. The status of signature, ratification, acceptance, approval or accession by States or organizations as of 31 July 1990 is presented in an attachment

  15. Convention on the physical protection of nuclear material

    International Nuclear Information System (INIS)

    1982-01-01

    The document presents the original draft for a Convention on the Physical Protection of Nuclear Material, full reports of all the discussions held by representatives of Member States at meetings called by the IAEA, texts of written comments provided by Member States and the final agreed text of the Convention, list of original signatory States and status of the list of signatory States at the date of publication

  16. Determination of half-value layers and tenth-value layer to barite as shielding against X radiation in radiological protection

    International Nuclear Information System (INIS)

    Lopes, G.A.; Aragao Filho, G.L.; Almeida Junior, A.T.; Santos, M.A.P.; Araujo, F.G.S.; Nogueira, M.S.

    2013-01-01

    The barium mortar has been widely used as radiation shielding material for X and gamma radiations in Brazil, by presenting some advantages as the high rate of efficiency in radiation shielding, the easy handling and application, the facility to be found in the national market and low cost. The determination of the half-value layers (HVL) and tenth-value layer (TVL) of different types of barite becomes the major factor to characterize the attenuation of these materials, in order to ensure the efficiency and quality of projects shielding, by ensuring the safety of workers occupationally exposed to radiation and of individuals to the public. Thus, plates of different thickness of mortar of barite were made for determination of their HVL and TVL. The plates were irradiated with X-ray qualities for radiological protection according to standard ISO 4037. A system of CdTe spectrometry was used to acquire spectra transmitted, in the presence of each plate, and their combinations. The areas of the spectra obtained, depending on the total thickness of the plates used in the arrangement were used to determine the attenuation curves. From these curves obtained in this work was to establish the HVL and TVL

  17. Gonadal shielding to irradiation is effective in protecting testicular growth and function in long-term survivors of bone marrow transplantation during childhood or adolescence.

    Science.gov (United States)

    Ishiguro, H; Yasuda, Y; Tomita, Y; Shinagawa, T; Shimizu, T; Morimoto, T; Hattori, K; Matsumoto, M; Inoue, H; Yabe, H; Yabe, M; Shinohara, O; Kato, S

    2007-04-01

    An increasing number of long-term surviving bone marrow transplantation (BMT) recipients have recovered from their primary disease but are at risk of developing failure of endocrine organs. We investigated 30 recipients who underwent allogeneic BMT during childhood or adolescence. Testicular growth and function were evaluated by serial measurement of testicular volume, basal luteinizing hormone (LH), basal follicle-stimulating hormone (FSH) and testosterone levels and by gonadotropin-releasing hormone (GnRH) provocative test. Puberty started spontaneously in all patients. However, all except four patients had normal testosterone levels with elevated LH, indicating partial Leydig cell dysfunction. Standard deviation scores of testicular volume at last evaluation were statistically lower in those who had received irradiation without gonadal shield compared to those with (-2.04+/-0.45 vs -0.30+/-1.17, respectively, Pgonadal irradiation. Serial measurement of testicular volume showed a tendency of growth to stop at 10 ml in those without gonadal shield. Among the 30 patients, only one patient has fathered a child after reaching spontaneous puberty. These results suggest that gonadal shield is effective to protect testicular growth and function, although the attainment of fertility is difficult to achieve.

  18. Self-shielding factors

    International Nuclear Information System (INIS)

    Kaul, D.C.

    1982-01-01

    Throughout the last two decades many efforts have been made to estimate the effect of body self-shielding on organ doses from externally incident neutrons and gamma rays. These began with the use of simple geometry phantoms and have culminated in the use of detailed anthropomorphic phantoms. In a recent effort, adjoint Monte Carlo analysis techniques have been used to determine dose and dose equivalent to the active marrow as a function of energy and angle of neutron fluence externally incident on an anthropomorphic phantom. When combined with fluences from actual nuclear devices, these dose-to-fluence factors result in marrow dose values that demonstrate great sensitivity to variations in device type, range, and body orientation. Under a state-of-the-art radiation transport analysis demonstration program for the Japanese cities, sponsored by the Defense Nuclear Agency at the request of the National Council on Radiation Protection and Measurements, the marrow dose study referred to above is being repeated to obtain spectral distributions within the marrow for externally incident neutrons and gamma rays of arbitrary energy and angle. This is intended to allow radiobiologists and epidemiologists to select and to modify numbers of merit for correlation with health effects and to permit a greater understanding of the relationship between human and laboratory subject dosimetry

  19. Safeguards Strategy in Physical Protection System for Nuclear Installation

    International Nuclear Information System (INIS)

    Ade lndra B; Kasturi; Tatang Eryadi

    2004-01-01

    Safeguards strategy is directed at efforts of eliminating theft of nuclear materials and sabotage of nuclear installation. For achieving the above objective, it is necessary to set up safeguards strategy in physical protection of nuclear materials and installation. The safeguards strategy starts from anticipated security condition, list of thefts, planning referred to as safeguards planning. Safeguards planning are implemented in safeguards implementation, followed up then by evaluation. Results of evaluation are equipped with results of safeguards survey already developed. Safeguards' planning is made from these results and serve as guidelines for next safeguards implementation and is repeated to form a safeguard cycle. One safeguard cycle is made on a periodical basis, at least annually. (author)

  20. Handbook on care, handling and protection of nuclear medicine instruments

    International Nuclear Information System (INIS)

    2000-11-01

    Instruments are fundamental to successful nuclear medicine practice. They must be properly installed in an environment in which they can give accurate and uninterrupted service. They have to be properly and carefully operated and supported throughout their life by regular care and maintenance. If something is wrong with a key instrument all well trained staff members are idle and all purchased radiopharmaceuticals become useless. Overall responsibility for instrumentation rests with the directors of nuclear medicine centres. They should support their electronic engineers, medical physicists, technologists and physicians to plan and implement the care and protection of nuclear medicine instruments, see that they are properly maintained, and kept in optimum working condition by regular checks. Protection should be considered, and provided for, before installing any new instrument. The protective devices are part of the new installation and should be well maintained along with the instrument throughout its life. Thus protection needs careful planning, particularly at the beginning of a new instrumentation programme. It can affect selection, procurement, acceptance testing, and the design of quality control and maintenance routines. These activities should be considered as important in their own right. They should not be mixed in with other functions or left to take care of themselves in the daily rush to get through routine work. Experience suggests that more than half of all failures of electronic equipment are due to damage by external electrical disturbances. Section 2 of this handbook aims to help instrument users in nuclear medicine centres to understand the nature of the various types of disturbance, and to protect against them. Section 3 shows how air conditioning can help to protect instrumentation. Section 4 lists some practical tips to avoid accidental damage due to mishandling. A computer program for use with Personal Computers, ''EPC Expert'' is described

  1. Meeting the Grand Challenge of Protecting Astronauts Health: Electrostatic Active Space Radiation Shielding for Deep Space Missions

    Science.gov (United States)

    Tripathi, Ram K.

    2016-01-01

    This report describes the research completed during 2011 for the NASA Innovative Advanced Concepts (NIAC) project. The research is motivated by the desire to safely send humans in deep space missions and to keep radiation exposures within permitted limits. To this end current material shielding, developed for low earth orbit missions, is not a viable option due to payload and cost penalties. The active radiation shielding is the path forward for such missions. To achieve active space radiation shielding innovative large lightweight gossamer space structures are used. The goal is to deflect enough positive ions without attracting negatively charged plasma and to investigate if a charged Gossamer structure can perform charge deflections without significant structural instabilities occurring. In this study different innovative configurations are explored to design an optimum active shielding. In addition, to establish technological feasibility experiments are performed with up to 10kV of membrane charging, and an electron flux source with up to 5keV of energy and 5mA of current. While these charge flux energy levels are much less than those encountered in space, the fundamental coupled interaction of charged Gossamer structures with the ambient charge flux can be experimentally investigated. Of interest are, will the EIMS remain inflated during the charge deflections, and are there visible charge flux interactions. Aluminum coated Mylar membrane prototype structures are created to test their inflation capability using electrostatic charging. To simulate the charge flux, a 5keV electron emitter is utilized. The remaining charge flux at the end of the test chamber is measured with a Faraday cup mounted on a movable boom. A range of experiments with this electron emitter and detector were performed within a 30x60cm vacuum chamber with vacuum environment capability of 10-7 Torr. Experiments are performed with the charge flux aimed at the electrostatically inflated

  2. IAEA outlines measures to enhance protection against nuclear terrorism

    International Nuclear Information System (INIS)

    2001-01-01

    Mr. ElBaradei, head of the IAEA presented a report today to the Agency's Board of Governors, outlining plans for substantially expanding and strengthening IAEA programmes relevant to improving nuclear security. The report addresses the IAEA's response to the following threats from acts of nuclear terrorism by a subnational group: acquisition of a nuclear weapon; acquisition of nuclear material to construct a nuclear weapon or to cause a radiological hazard; acquisition of other radioactive materials to cause a radiological hazard; and violent acts against nuclear facilities to cause a radiological hazard. The report puts a price tag on its proposed programme upgrades at $30-50 million per year, representing an initial 10-15% increase in the IAEA's overall resources. Additionally, Mr. ElBaradei said the IAEA's budget is currently underfeed by about $40 million due to a budgetary policy over many years of 'zero real growth', and called on Member States to provide the resources required to cope with the newly emerging threat. 'In addition to the resources required for urgent international assistance,' Mr. ElBaradei said, 'the necessary global upgrades to meet the full range of possible threats would be in the range of hundreds of millions of dollars and would have to be carried out by individual States and through bilateral and multilateral assistance'. The IAEA would play a coordinating role in delivering this assistance.If States provide adequate funding, Mr. ElBaradei predicts that the enhanced and additional activities proposed in his report should lead over time to a powerful national and international security framework for nuclear facilities and material. The Summary of Report on 'Protection Against Nuclear Terrorism' presented to the IAEA Board of Governors on 30.11.2001 is attached

  3. The Physical Protection of Nuclear Material; Proteccion Fisica Delos Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-09-15

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international cooperation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and materials, particularly when such materials are transported across national frontiers [French] La proteccion fisica contra el robo o la desviacion no autorizada de materiales nucleares y contra el sabotaje de las instalaciones nucleares por parte de individuos o de grupos ha sido durante largo tiempo motivo de preocupacion nacional e internacional. Aunque la obligacion de crear y hacer funcionar un sistema completo de proteccion fisica para las instalaciones y materiales nucleares en el territorio de un Estado determinado incumbe enteramente al Gobierno de dicho Estado, el que esa obligacion se cumpla o no, y si se cumple, en que medida o hasta que punto, es cosa que no deja indiferentes a los demas Estados. De aqui que la proteccion fisica se haya convertido en motivo de interes y cooperacion internacional. La necesidad de cooperacion internacional se hace evidente en los casos en que la eficacia de la proteccion fisica en el territorio de un Estado depende de que otros Estados tomen tambien medidas apropiadas para evitar o hacer fracasar los actos hostiles dirigidos contra instalaciones y

  4. The protection system to Brazilian Nuclear Program; O sistema de protecao ao Programa Nuclear Brasileiro

    Energy Technology Data Exchange (ETDEWEB)

    Andreuzza, Mario Giussepp Santezzi Bertottelli [Secretaria de Assuntos Estrategicos (SAE), Brasilia, DF (Brazil)

    1997-12-31

    The Sistema de Protecao ao Programa Nuclear Brasileiro-SIPRON (Protection System to Brazilian Nuclear Program) was established in 1980. It is intended to accomplish in only one system, all the actions related to security and protection for Nuclear Facilities in Brazil. The author presents in detail the protection system SIPRON, describing the system structure and organization, the functions and obligations of the system involved main organizations, as well as, the system operation and behaviour during an postulated occurrence of a nuclear emergency. It is also described an Exercise that happened in June of 1997 at the Nuclear Power Plant (NPP) Angra I, after two simulated tests in December of 1996 and April of 1997. The NPP Angra I Emergency Plan Exercise was a good opportunity to test the SIPRON structure and preparedness program. It was verified, included by International Atomic Energy Agency observers, the system involved organizations effectiveness and the procedures efficacy to protect the public and the environmental. Finally, it is shown the SIPRON activities of routine, the system obstacles and the expected future performances. (author) 3 refs., 3 figs.

  5. HPGe detector shielding adjustment

    International Nuclear Information System (INIS)

    Trnkova, L.; Rulik, P.

    2008-01-01

    Low-level background shielding of HPGe detectors is used mainly for environmental samples with very low content of radionuclides. National Radiation Protection Institute (SURO) in Prague is equipped with 14 HPGe detectors with relative efficiency up to 150%. The detectors are placed in a room built from materials with low content of natural radionuclides and equipped with a double isolation of the floor against radon. Detectors themselves are placed in lead or steel shielding. Steel shielding with one of these detectors with relative efficiency of 100% was chosen to be rebuilt to achieve lower minimum detectable activity (MDA). Additional lead and copper shielding was built up inside the original steel shielding to reduce the volume of the inner space and filled with nitrogen by means of evaporating liquid nitrogen. The additional lead and copper shielding, consequent reduction of the inner volume and supply of evaporated nitrogen, caused a decrease of the background count and accordingly MDA values as well. The effect of nitrogen evaporation on the net areas of peaks belonging to radon daughters is significant. The enhanced shielding adjustment has the biggest influence in low energy range, what can be seen in collected data. MDA values in energy range from 30 keV to 400 keV decreased to 0.65-0.85 of original value, in energy range from 400 keV to 2 MeV they fell to 0.70-0.97 of original value. (authors)

  6. Beta Bremsstrahlung dose in concrete shielding

    Energy Technology Data Exchange (ETDEWEB)

    Manjunatha, H.C., E-mail: manjunatha@rediffmail.com [Department of Physics, Government college for women, Kolar 563101, Karnataka (India); Chandrika, B.M. [Shravana, 592, Ist Cross, Behind St.Anne s School, PC Extension, Kolar 563101, Karnataka (India); Rudraswamy, B. [Department of Physics, Bangalore University, Bangalore 560056, Karnataka (India); Sankarshan, B.M. [Shravana, 592, Ist Cross, Behind St.Anne s School, PC Extension, Kolar 563101, Karnataka (India)

    2012-05-11

    In a nuclear reactor, beta nuclides are released during nuclear reactions. These betas interact with shielding concrete and produces external Bremsstrahlung (EB) radiation. To estimate Bremsstrahlung dose and shield efficiency in concrete, it is essential to know Bremsstrahlung distribution or spectra. The present work formulated a new method to evaluate the EB spectrum and hence Bremsstrahlung dose of beta nuclides ({sup 32}P, {sup 89}Sr, {sup 90}Sr-{sup 90}Y, {sup 90}Y, {sup 91}Y, {sup 208}Tl, {sup 210}Bi, {sup 234}Pa and {sup 40}K) in concrete. The Bremsstrahlung yield of these beta nuclides in concrete is also estimated. The Bremsstrahlung yield in concrete due to {sup 90}Sr-{sup 90}Y is higher than those of other given nuclides. This estimated spectrum is accurate because it is based on more accurate modified atomic number (Z{sub mod}) and Seltzer's data, where an electron-electron interaction is also included. Presented data in concrete provide a quick and convenient reference for radiation protection. The present methodology can be used to calculate the Bremsstrahlung dose in nuclear shielding materials. It can be quickly employed to give a first pass dose estimate prior to a more detailed experimental study. - Highlights: Black-Right-Pointing-Pointer Betas released in a nuclear reactor interact with shielding concrete and produces Bremsstrahlung. Black-Right-Pointing-Pointer The present work formulated a new method to evaluate the Bremsstrahlung spectrum and dose in concrete. Black-Right-Pointing-Pointer Presented data in concrete provide a quick and convenient reference for radiation protection.

  7. Nuclear Magnetic Shielding Constants from Quantum Mechanical/Molecular Mechanical Calculations Using Polarizable Embedding: Role of the Embedding Potential

    DEFF Research Database (Denmark)

    Steinmann, Casper; Olsen, Jógvan Magnus Haugaard; Kongsted, Jacob

    2014-01-01

    We present NMR shielding constants obtained through quantum mechanical/molecular mechanical (QM/MM) embedding calculations. Contrary to previous reports, we show that a relatively small QM region is sufficient, provided that a high-quality embedding potential is used. The calculated averaged NMR...... shielding constants of both acrolein and acetone solvated in water are based on a number of snapshots extracted from classical molecular dynamics simulations. We focus on the carbonyl chromophore in both molecules, which shows large solvation effects, and we study the convergence of shielding constants...

  8. The Physical Protection of Nuclear Material and Nuclear Facilities; Proteccion Fisica De Los Materiales Y Las Instalaciones Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-15

    Physical protection against the theft or unauthorized diversion of nuclear materials and against the sabotage of nuclear facilities by individuals or groups has long been a matter of national and international concern. Although responsibility for establishing and operating a comprehensive physical protection system for nuclear materials and facilities within a State rests entirely with the Government of that State, it is not a matter of indifference to other States whether and to what extent that responsibility is fulfilled. Physical protection has therefore become a matter of international concern and co-operation. The need for international co-operation becomes evident in situations where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter or defeat hostile actions against nuclear facilities and nuclear materials, particularly when such materials are transported across national frontiers [Spanish] La proteccion fisica contra el robo o la desviacion no autorizada de materiales nucleares y contra el sabotaje de las instalaciones nucleares por parte de individuos o grupos es motivo de preocupacion nacional e internacional desde hace mucho tiempo. Aunque la obligacion de crear y hacer funcionar un sistema completo de proteccion fisica de las instalaciones y materiales nucleares en el territorio de un Estado determinado incumbe exclusivamente al Gobierno de dicho Estado, el que esa obligacion se cumpla o no, y si se cumple, en que medida o hasta que punto, son cosas que no dejan indiferentes a los demas Estados. Por ello, la proteccion fisica se ha convertido en motivo de interes y cooperacion internacional. La necesidad de la cooperacion internacional se hace evidente en los casos en que la eficacia de la proteccion fisica en el territorio de un Estado depende de que otros Estados tomen tambien medidas apropiadas para evitar o hacer fracasar los actos hostiles dirigidos contra instalaciones y

  9. Progress report: nuclear safety and radiation protection in 2006

    International Nuclear Information System (INIS)

    2007-01-01

    For the French Nuclear Safety Authority (Asn), the year 2006 was marked by two important nuclear laws being passed, one of which brought about a major change in its status. The year was a relatively satisfactory one with regard to nuclear safety, although the picture was more contrasted concerning radiation protection: in this area, more particularly in the medical field, the overall impression of good progress is offset by the declaration of a number of radiotherapy accidents. Given the benefits expected from radiotherapy treatment by the patient suffering from cancer, the conditions in which this activity is carried out are a subject of major concern for Asn, in the light of the serious risks linked to patient over-exposure. ( some important points as follows: the law on transparency and security in the nuclear field, the law on sustainable management of radioactive materials and waste, Asn: an independent administrative authority, EPR reactor project safety, I.R.R.S.: an international audit of Asn in 2006, harmonization of nuclear safety, cancer radiotherapy, improved information of the public after the T.S.N. law, taking account of organisational and human factors). (N.C.)

  10. Nuclear materials management handbook. Safeguards, physical protection of nuclear material. 1995 ed.

    International Nuclear Information System (INIS)

    1995-01-01

    Now, very safe and stable supply of electric power has become to be obtained by nuclear energy, and Japan has steadily promoted nuclear power as the basic energy that contributes to overcome the unstable structure of energy supply in Japan highly depending on foreign countries, as shown in the long term plan of the research, development and utilization of nuclear power. Great progress was observed in nuclear fuel recycling in Japan such as the attainment of initial criticality of the prototype FBR 'Monju' and the start of construction of the commercial fuel reprocessing plant in Rokkasho. Recently the recognition of the importance of nuclear substance management has heightened, and the measures for maintaining and strengthening the reliability of nuclear nonproliferation system are investigated. It is important that Japan strictly observes the nuclear nonproliferation system based on the NPT which was extended infinitely. In this handbook, the outline of the measures for nuclear nonproliferation and safeguard and the protection of nuclear substances, the treaties and agreements and the national laws related to these are described. (K.I.)

  11. Proposal for a radiation shielding study aiming the implantation of neutrons beam shutter in the J-9 radiation channel of the Argonauta reactor of the Nuclear Engineering Institute

    Energy Technology Data Exchange (ETDEWEB)

    Xavier, Larissa R.P.; Cardoso, Domingos D’Oliveira, E-mail: larissa.xavier@cnen.gov.br, E-mail: domingosoliveiralvr71@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Ferreira, Francisco José de Oliveira; Voi, Dante Luiz, E-mail: fferreira@ien.gov.br, E-mail: dante@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    Argonauta, the only nuclear research reactor situated in Rio de Janeiro, located at the Institute of Nuclear Engineering (IEN), regularly serves a network of users focused on research and development, and also provides its infrastructure for experimental classes and completion work course. Due to increasing demand for non-destructive thermal neutron assays and production of radioisotopes, there is a search for new procedures and/or devices that optimize users' exposure to neutrons. The implementation of mechanisms that allow access to the irradiation channels without the reactor being turned off and with a shielding configuration that limits the occupational doses at this location is very useful for the operation of the reactor. In order to achieve this, the present work proposes the establishment of a neutron beam shutter of the J-9 irradiation channel of the IEN's Argonauta reactor. In a first step, experimental measurements were made in the irradiation channel of the reactor using a BF3 detector, which is coupled to a spectrometer. In this phase, the neutron beam was aligned to the spectrometer, and different materials were used as shields, aiming the attenuation of the beam. To validate and/or change the configuration of the barrier that best meets the material irradiation needs, a second planned phase is involving the neutron flux simulation of the reactor and the various shields with different boundary conditions using the particle transport code, Monte Carlo N-Particle Extended (MCNP- X). (author)

  12. Proposal for a radiation shielding study aiming the implantation of neutrons beam shutter in the J-9 radiation channel of the Argonauta reactor of the Nuclear Engineering Institute

    International Nuclear Information System (INIS)

    Xavier, Larissa R.P.; Cardoso, Domingos D’Oliveira; Ferreira, Francisco José de Oliveira; Voi, Dante Luiz

    2017-01-01

    Argonauta, the only nuclear research reactor situated in Rio de Janeiro, located at the Institute of Nuclear Engineering (IEN), regularly serves a network of users focused on research and development, and also provides its infrastructure for experimental classes and completion work course. Due to increasing demand for non-destructive thermal neutron assays and production of radioisotopes, there is a search for new procedures and/or devices that optimize users' exposure to neutrons. The implementation of mechanisms that allow access to the irradiation channels without the reactor being turned off and with a shielding configuration that limits the occupational doses at this location is very useful for the operation of the reactor. In order to achieve this, the present work proposes the establishment of a neutron beam shutter of the J-9 irradiation channel of the IEN's Argonauta reactor. In a first step, experimental measurements were made in the irradiation channel of the reactor using a BF3 detector, which is coupled to a spectrometer. In this phase, the neutron beam was aligned to the spectrometer, and different materials were used as shields, aiming the attenuation of the beam. To validate and/or change the configuration of the barrier that best meets the material irradiation needs, a second planned phase is involving the neutron flux simulation of the reactor and the various shields with different boundary conditions using the particle transport code, Monte Carlo N-Particle Extended (MCNP- X). (author)

  13. WINRE '92 - 3rd workshop on information management in nuclear safety, radiation protection, and environmental protection

    International Nuclear Information System (INIS)

    Hoepfner, K.A.

    1993-01-01

    The workshop puts much emphasis on the exchange of experience between experts from the West and from the Central and Eastern European countries. The representatives from the various countries and organisations are going to introduce their respective data banks, products, or services. The combination of papers and practical presentations will provide all with a qualified and comprehensive insight into the tried and tested as well as the new information management technologies in the specialist areas of nuclear safety, radiation protection, and environmental protection. Furthermore, it should also contribute to the promotion of the transfer of know-how between experts throughout the whole of Europe. (orig./DG)

  14. Shielding container

    International Nuclear Information System (INIS)

    Darling, K.A.M.

    1981-01-01

    A shielding container incorporates a dense shield, for example of depleted uranium, cast around a tubular member of curvilinear configuration for accommodating a radiation source capsule. A lining for the tubular member, in the form of a close-coiled flexible guide, provides easy replaceability to counter wear while the container is in service. Container life is extended, and maintenance costs are reduced. (author)

  15. Decree of the Czechoslovak Atomic Energy Commission concerning the security protection of nuclear installations and nuclear materials

    International Nuclear Information System (INIS)

    1989-01-01

    In compliance with the Czechoslovak State Surveillance over Nuclear Safety of Nuclear Installations Act No. 28/1984, the Decree specifies requirements for assuring security protection of nuclear installations (and their parts) and of nuclear materials with the aim to prevent their abuse for jeopardizing the environment and the health and lives of people. (P.A.)

  16. Absolute NMR shielding scales and nuclear spin–rotation constants in {sup 175}LuX and {sup 197}AuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br and {sup 127}I)

    Energy Technology Data Exchange (ETDEWEB)

    Demissie, Taye B., E-mail: taye.b.demissie@uit.no; Komorovsky, Stanislav; Repisky, Michal; Ruud, Kenneth [Centre for Theoretical and Computational Chemistry, Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø (Norway); Jaszuński, Michał [Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01 224 Warszawa (Poland)

    2015-10-28

    We present nuclear spin–rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants, and shielding spans of all the nuclei in {sup 175}LuX and {sup 197}AuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br, {sup 127}I), calculated using coupled-cluster singles-and-doubles with a perturbative triples (CCSD(T)) correction theory, four-component relativistic density functional theory (relativistic DFT), and non-relativistic DFT. The total nuclear spin–rotation constants determined by adding the relativistic corrections obtained from DFT calculations to the CCSD(T) values are in general in agreement with available experimental data, indicating that the computational approach followed in this study allows us to predict reliable results for the unknown spin–rotation constants in these molecules. The total NMR absolute shielding constants are determined for all the nuclei following the same approach as that applied for the nuclear spin–rotation constants. In most of the molecules, relativistic effects significantly change the computed shielding constants, demonstrating that straightforward application of the non-relativistic formula relating the electronic contribution to the nuclear spin–rotation constants and the paramagnetic contribution to the shielding constants does not yield correct results. We also analyze the origin of the unusually large absolute shielding constant and its relativistic correction of gold in AuF compared to the other gold monohalides.

  17. Protective effect of blue-light shield eyewear for adults against light pollution from self-luminous devices used at night.

    Science.gov (United States)

    Ayaki, Masahiko; Hattori, Atsuhiko; Maruyama, Yusuke; Nakano, Masaki; Yoshimura, Michitaka; Kitazawa, Momoko; Negishi, Kazuno; Tsubota, Kazuo

    2016-01-01

    We investigated sleep quality and melatonin in 12 adults who wore blue-light shield or control eyewear 2 hours before sleep while using a self-luminous portable device, and assessed visual quality for the two eyewear types. Overnight melatonin secretion was significantly higher after using the blue-light shield (P light shield (P light shield as providing acceptable visual quality.

  18. Experience with a servo-hydraulic mechanical testing machine installed in a new shielded active facility at Windscale Nuclear Power Development Laboratories

    International Nuclear Information System (INIS)

    Garlick, A.; Hindmarch, P.; Gravenor, J.G.; Rhodes, D.

    1982-03-01

    An Instron model 1273 servo-hydraulic machine has been installed within a lead-shielded cell at Windscale in order to provide a facility capable of performing a wide range of mechanical tests on nuclear reactor structural materials and fuel assembly components. This particular type of machine was chosen because it has design features associated with the load frame, location of the actuator and adjustment and clamping of the cross-head that are especially well suited to remote operation within a shielded cell. The design of the testing facility is described and the programmes of work that have been completed over the past 11/2 years of operation are reviewed. (author)

  19. Nanoscopic designs of radiological protection in environmental scale for the Fukushima nuclear accident: Strategy by dispersion, dissolution, and filtration

    International Nuclear Information System (INIS)

    Woo, Tae Ho

    2016-01-01

    Highlights: • New kind of radiological protection concept is introduced. • The shielding concept is accompanied with the water spray system. • The solubility of radioactive material could be used for protection. • Practical method is suggested. • The system is variable by the random number quantities. - Abstract: The environmental defense system in the nuclear power plants (NPPs) is investigated in the aspect of the environmental scale incorporated with atmospheric and marine sectors. The object is to find the radiological protection protocol in the environmental scale which is different from the conventional three kinds of radiological protection principles. Conventional laboratory based principles are not applicable in the mass failure accident such as the case of Fukushima disaster. This newly introduced protocol has many useful applications for the nature treatment oriented methods where the atmospheric protection of dispersion and dissolution is performed first and the filtration of seawater would follow. The maximum and minimum values in fan velocity are about 7.5 m/s and 5.3 m/s respectively. For the spray system, the mole fractions by the water spray are shown where maximum and minimum values are 6.57 × 10 −17 and 8.84 × 10 −19 moles respectively. The maximum and minimum values of discharged values in filtration are 99.4 and 1.3 square velocity (m/s), respectively. The total and general radiological protection concept is suggested in the nanoscopic molecular scale performance.

  20. Nuclear safety and radiation protection report of the Cruas-Meysse nuclear facilities - 2014

    International Nuclear Information System (INIS)

    2015-01-01

    This safety report was established in accordance with articles L. 125-15 and L. 125-16 of the French environmental code. It presents, first, the NPPs (INBs no. 111 and 112). Then, the nuclear safety and radiation protection measures taken regarding the facilities are reviewed: nuclear safety definition, radiation protection of intervening parties, safety and radiation protection improvement paths, crisis management, external and internal controls, technical situation of facilities, administrative procedures in progress. The incidents and accidents which occurred in 2014, if any, are reported as well as the radioactive and non-radioactive effluents discharge in the environment. Finally, the radioactive materials and wastes generated by the facility are presented (type of waste, quantities, conditioning process). The document concludes with a presentation of the actions of communication and public information made by the direction of the facility. A glossary and the list of recommendations from the Committees for health, safety and working conditions are given in appendix