05 Nuclear fuels (scientific, technical)

95/03614 International activities in the field of probabilistic safety assessment and the development of a Level 1 metholodology In Finland Virolainen, R. K. Kerntechnik, May 1995, 60, (2), 82-87. The activities of the OECD’s Nuclear Energy Agency in the field of proba- bilistic safetv assessment are reviewed. The activities include surveys of PSA methods used for low power operation and shutdown conditiois, of the methods used to assess human reliability, and of the methods of Level 1 PSA. A research project of th Nordic countries which deals with safety evaluation by Living PSA is briefly approach introduced by the Finnish E

resented. A new Living Level 2 PSA entre of Radiation and Nuclear Safety

is discussed in some detail. The approach is based upon integration of the Living Level 1 and 2 PSA models, and parametric modelling of severe accident progression and fission product transport.

95103623 On the potential of probabilistic safety assessment Berg, H. P. Kerntechnik, May 1995, 60, (2), p. 71. The short paper discusses the application of probabilistic safety assessment (PSA) in the last few decades which has successfully demonstrated its capability to contribute to the safe operation of nuclear power plants.

95103624 Probabilistic fire risk analysis Hoffmann, H. H. et al., Kernrechnik, May 1995, 60, (2), 117-121. The evaluation of the, risk associated with fires in nuclear power plants has attracted considerable attention in the last few years. Detailed safety assessments have shown that the conseauences of fires can be sienificant. Methodologies considering fire in probabilistic safety analyses h&e been developed such that a probabilistic fire risk analysis can serve as an addi- tional tool for the safety assessment of a nuclear power plant. An approach which is being developed for the nuclear power plants in Germany is

95103615 International activities to improve the methods of presented in some detail. Major ste

probabilistic safety assessment and to support its applications screening process to identify critica P, s of thii approach are the qualitative fire zones and the quantitative event

Tomic, B. Kerntechnik, May 1995, 60, (2), 75-81. The oaoer uresents the chronoloeical develooment of orobabilistic safetv

tree analysis to assess fire caused frequencies of initiating events and core damage states.

asse&ent=(PSA) with emphasison the worldwide de;elopment of me& ods. The IAEA programme an PSA is described. These activities include technical cooperation, international PSA training, and interriational peer review services. The status of PSA activities in central and eastern Europe is discussed in detail with emphasis on IAEA supplied assistance. Other international suooort including some PSA activities for RBMK reactors is also addressed. ‘Emerging PSK applications programmes are presented, e.g. the regulatory use of PSA.

95103616 IV0 prepares to anneal RPV at Loviisa 1 Ahlstrand, R. Nuclear Engng. Inf., Jun. 1993, 40, (491), 20-21. Reports that in 1980, only three years after the start up of Loviisa 1, a Soviet- designed VVER-440 reactor, a much higher rate of pressure vessel embrittlement than expected was observed. Although the measures taken to control embrittlement have been uite successful, IV0 decided to carry out an annealing of the main core we 9 d. A comprehensive programme of work has been underway to determine the precise state of the vessel, to develop the safety case for licencing the annealing operation, and to plan the actual procedure, which will be carried out in 1996.

95103625 Probabilistic safety assessment for non-full-power states of nuclear power plants Muller-Ecker, D. and Simon, M. Kerntechnik, May 1995, 60, (2), 122-129. It has become obvious in the last few years that non-full-power states may have a significant impact on the safkty of a nuclear power plant. In B logical extension of the application of probabilistic safety assessment (PSA). slant states other than Dower oueration states are analvsed now in iearl$’ all countries o

B erating’ nuclear’ plants, The applicatidn to events

during low-power an shutdown states requires further development of PSA methodology in many areas. The paper describes the international state of the art and presents some details of studies performed for a pres- surized water reactor and a boiling water reactor.

95103626 Proceedings Advances In Reactor Physics, Knox- ville, TN, April 1’1-15 1994 Order No.700215, $150.00, American Nuclear Sociery, 555 N. Kensington

Ave., LaGrange Park, IL.60525, USA.

95103617 Japan’s No. 1 Demonstration FBR Nedderman, J. Nuclear Engng. Inf., May 1995, 40, (490), 22-25.

95103627 Proceedings DOE S and Initiatives, S It Lake City, U P

ent Nuclear Fuel: Challenges

! , December 14-16 1994,

Order No.700214. 70.00. American Nuclear Socieni 555 N. Kensington The author discusses how sy-reducing costs, J$an&e utilities propose eventuallv to uroduce a fast breeder reactor which can compete with light water po&er ilants. The features of the No. 1 Demonstratiob Fast Breelder Reactor has been honed to achieve this goal without compromising safety, and all the research work done so far shows that the design targets set can be reached.

Ave., LaGrange P&k, IL.80525, USA. I. 1

95103626 Procegdings Nuclear Data for Science and Tech- nology, Gatlinburg, TN, May 9-13 1994 Order No. 700205, $130.00, American Nuclear Society, 555 N. Kensington

Ave., LaGrange Park, IL.60525, USA.

95103618 Korea goes as low as reasonably achievable Lee, D. et al., Nuclear Engng. Int., May 1995, 40, (490), 37-38. Discusses the growing nuclear programme in Sguth Korea which must be matched by its radiation protection infrastructure. The use of ALARA prin- ciples, and a new ALARA Centre will help meet this need.

95103629 Proceedings Physics, Safety and Application of Pulse Reactors, Washington, DC, November 13-17 1994, Order No.700207, $45.00, American Nuclear Society, 555 N. Kensington

Ave., LaGrange Park, IL.60525, USA.

95103619 Living probabilistic safety assessment Balfanz, H. P. et al., Kerntechnik, May 1995, 60, (2), 110-116. The paper gives an overview of the development, the objectives and the scope of Living probabilistic safety assessmeht. Its methods, tools and imoortant features of aoolication are described. The Safetv Analvsis and Information System is &ed as an example. The main part bf this’SSystem, viz, the top-down fault and event tree modelling and the bottom-up engi- neering system analysis, are described. Some details of the special data sheet method, which is used for data collection and processing, are presented. A special approach for common cause failure analysis is explained. The practicability of the System as an aid for utilities and plant staff has been demonstrated at nuclear plants of different types.

95JO3620 Managing safety in the face of economic pressures Carlton. J. D. and Brooks, B. L. Nuclear Ennna. In?.. May 1995, 40, (490). 47-48.

_ I

The authors discuss how since 1980, operators of B&W nuclear units have responsed to economic and safety challenges as a group. This has helped increase safety and availability while reducing costs.

95103621 Nuclear power: Safe and green Comby, B. Insritut Bruno Comby, 8 rue de la Croix Blanche, 78240 Chambourcy, France, 98 Fr, 240 pp. The book which is published in French takes a positive approach to nuclear energy from an ecological perspective.

95103622 Nuclear powered aircraft? Sellix. R. E. Power Enpnp. J.. Aor. 1995. 9. (21. 102-104. Disc&es a fascinating s&i w&&was tolh dy’d; Bob Hall in his recent lecture lo the IEE Power Division entitled ‘A personal history of the UK civil nuclear industry’.

95103630 Protecting fuel assemblies from corrosion Seibold, A. et al., Nuclear News, Apr. 1995, 38, (5), 36-37. Reports that iron-alloyed zirconium liners have redu&d the risk of serious secondary damage to fuel cladding tubes. The vast majority of cladding tubes for light-water reactor fuel assemblies are made of Zircaloy, with a distinction being made for historical reasons, between Zircaloy-2 (for boil- ing water reactors) and Zircaloy-4 (for pressurized water reactors). The basis of both alloys is zirconium, to which tin, iron, chromium, and, in the case of Zircaloy-2, traces of nickel are added to enhance the material’s mechanical strength and corrosion resistance when exposed to water and steam.

95103631 Radiochemistry and nuclear chemistry Reed Book Services Ltd., PO Box 56, Rushden, Northants NNIO 9yX, UK,

f25.00. This new edition of Nuclear Chemistry, Theory and Applications has been completely rewritten and restructured to suit teaching and learning needs in a wide range of chemistry courses in radiochemistry, or more advanced nuclear chemistry courses. It contains over 200 exercises, with model answers.

95103632 The role of probabilistic limits for the assessment of the safety of nuclear power plants Berg, H. P. et al., Kerntechnik, May 1995, 60. (2), 135-138. Probabilistic safety assessment (PSA) provides quantitative information on the probability of event sequences relevant to plant safety. Criteria for PSA results can be defined and implemented into the regulatory process. This process is presented on the international scale for OECD member states. In practically all of the countries PSA is used to a great extent. Limits are available for core damage frequency and the frequency of large releases, but on different levels of obligation ranging from recommendations to regulatory requriements. In general the limit values are imbedded into sub- stantially different regulatory schemes so that the isolated comparison or discussion of limits can lead to wrong conclusions.

Fuel and Energy Abstracts July 1995 263