No abstract available

[en] Recently at the Italian Institute of Health an interactive algorithm (RANA - Radiological Assessment of Nuclear Accidents) has been developed to evaluate the space and time structure of the radiological consequences of an accident at a nuclear plant in Europe. Individual or collective doses from several exposure paths are calculated, either starting from the source term or from air and ground contamination data. The algorithm, formulated in the language of Mathematica, can be run on a personal computer. After 11 September 2001, the risks associated with nuclear terrorism have been the subject of increasing attention. Three categories of risk have been identified: theft of nuclear material, physical attack or sabotage action onto a nuclear facility or use of one or more radioactive sources in a radiological dispersion device. The above mentioned algorithm has been therefore expanded to allow dealing with an arbitrary source term, as could be the case in a sabotage-induced accident, allowing for both somatic (short distance) and stochastic effects evaluation. Along with the previous functions of RANA, a new set of tools allows the user to evaluate also the areas where doses (from several pathways and to all age classes) exceed those at which onset of deterministic effects begin, a variable that plays a major role in emergency planning. In this paper the radiological risks related to the hypothetical use of radioactive sources in a dispersion device have been evaluated. By means of the improved version of the model, the doses as a function of the distance from the release point, for those sources that may be of concern for use in a dispersion device, are evaluated, taking into account the relevant exposure paths in the early emergency phase. For emergency planning purposes the distances within which the absorbed doses (to bone marrow) exceed the threshold values for deterministic effects have been assessed too. A radiological ranking of the most significant accidents related to a few realistic dispersion devices is proposed. (authors)

[en] The emergency situations which could arise are strictly connected with the possible accident type and strongly depend on the facilities existing in the country. This paper concerns the situation in Italy. Pre and post-Chernobyl accident situation are presented. Until 1986, a decree dated 1964 set out the actions to implement following a nuclear accident (preventing procedures, definition of the accident situation, emergency zones, responsibilities and duties of various bodies in case of emergency). In 1987, the Italian government decided a nuclear moratorium. Reference scenario for nationwide emergencies were defined as well as protective measures. An organisation structure was set up called the National Emergency plan. It was never implemented as far as nuclear power plant are concerned. However, it will become effective if the need arises (for example, in case of accidents involving nuclear release of nuclear plans, ships, satellites, etc...). (TEC). 2 refs., 3 figs., 3 tabs

[en] Measurements were carried out of parallel magnetic critical fields of pure tin films with thicknesses ranging from 1000 to 34000 A as a function of the temperatures. The results are found to be in good agreement with the Ginzburg-Landau theory for thin films. In the intermediate thickness range the experimental results are compared with the predictions of a recent model. The transition from thin- to thick-film behaviour has been studied. From the data the thickness dependence of the penetration depth lambda(0, d) has been evaluated. (orig.)

[en] After the Chernobyl accident many countries renewed their radiological emergency plans, also considering the possibility of over boundary accidents. This has been set out by the 96/29/Euratom Directive (Council Directive, 1996), which states that ^Each Member State shall ensure that account is taken of the fact that radiological emergencies may occur in connection with practices on or outside its territory and affect it^. Moreover, after September 11, 2001, the need to prepare emergency plans for possible terroristic attacks became evident and these plans are now being worked out in many countries for intervention in case of biological, chemical and/or radiological risk. In the event of radiological emergency, all decisions to be taken are based on possible doses to critical groups (European Commission, 1997), which are the population groups most at risk. These critical groups are, in most cases, infants or children, given that dose coefficients for these age groups are generally higher than for adults. However, a new ICRP Recommendation (ICRP, 2001) has recently been published that gives dose coefficients for embryo/foetus due to intake by the mother, by inhalation or ingestion, of 31 radionuclides. Also as a result of the revaluation in the last years of the possible health effects of prenatal exposure to ionising radiation (see e.g. the review in P. Fattibene et al., 1999), the consequences for the embryo/foetus of a possible radiological emergency connected to a nuclear plant and to possible dispersion of Depleted Uranium (DU) in the environment are analysed and discussed in this paper. For the former type of accident, Derived Intervention Levels (DILs) are calculated for prenatal exposure due to acute inhalation by the mother (female member of the public) and an assessment is performed of ingestion doses for the offspring resulting from consumption of foodstuffs by the mother of which 10% of the annual consumption is contaminated at the maximum levels permitted by the Council Regulation (Council Regulation, 1987). For Depleted Uranium, DILs are calculated for acute inhalation and chronic ingestion by the mother of contaminated drinking water

[en] A systematic study of human milk contamination due to the Chernobyl fall-out was conducted from May 1986 to December 1988 in the Rome area. A comparison was made with the contamination in the same period in other infant food, that is, cows' and powdered milk. The thyroid and effective dose equivalent for breast fed infants born in different periods were evaluated. Using average main food contamination data in the same area, an assessment of the transfer coefficient between the mothers' diet and their milk was performed. ⁴⁰K content of this milk was also measured and is discussed in the paper. An extension of the sampling to other areas was made in 1987 and 1988. (author)

[en] Perpendicular magnetic-field transitions of pure Sn films, assessed by microwave absorption measurement as a function of specimen thickness (65 nm-200 μ) and temperature (1.5 K-Tmc) are presented. The passage from intermediate- to mixed-state behaviour was observed. The values obtained for the critical thickness d perpendicular at which the passage from type-I to type-II behaviour occurs agree with theoretical predictions. Critical perpendicular megnetic field values, H perpendicular, also agree well with theoretical predictions for d< d perpendicular and in the limit d>>d perpendicular

[en] All the nuclear plants in Italy have ended their commercial activity more than 15 years ago and practically since then they are in the decommissioning phase together with other facilities of the nuclear fuel cycle. From the radioprotection point of view, the decommissioning phase has a minor impact than that related to the production phase. For the aspects regarding the general public, liquid discharges and gaseous effluents are at lower levels and accident analyses foresee events at lower scale; for what regards workers, operations with high level-wastes are, in principle, not more demanding in term of radiation doses than several inspection or replacement operations needed in maintenance periods during the commercial life of the nuclear plant. Then, as such, the decommissioning phase does not raise particular radioprotection problems and certainly it is of less radiological risk than the previous phase. There are however other considerations that make this phase of relevant potential risk if actions are not coordinate in a global scheme aiming to solve all the problems that this phase sets. The situation in Italy of temporary depositories of radioactive wastes has already been shown. On the contrary than in almost all European countries Italy has not a licensed centralized repository for low-medium activity wastes, not to speak of HLW. The localisation, on more than 25 places scattered all over the territory, of wastes stemming from medical activity and previous nuclear power activity as well as of spent fuel elements is from the radiological protection point of view far from being an optimised solution. Solidified high activity wastes in glass matrix, resulting from the Italian spent fuel elements reprocessed by BNFL that should be returned to our country, make the problem even worst. The need for the establishment of a national repository for nuclear wastes, raised by technical-scientific institutions long time ago, has become in Italy a shared objective among all institutional bodies in 1997. In that year ENEL application for decommissioning license of its plants with a SAFSTOR approach, deferring the dismantling within 50 years, was rejected by the Ministry of Industry, responsible of the authorization procedure, following similar comments and opinions expressed, in the foreseen licensing procedure by the Ministry of Health, APAT and other administrations. The Ministry of Industry published at the end of 1999 a document addressing 'Strategic Directions for the management of the outcome of the nuclear commercial phase'. Three general objectives with relative time lines were defined. The first two regarded the conditioning of all radioactive wastes present in the national territory and the siting, construction and commissioning of the national repository. These objectives should have been reached within 10 years. The third objective concerns the unrestricted release of the sites where the four nuclear power plants are localized. This last objective should be pursued through an accelerated dismantling (DECON) strategy within 20 years. In the framework of the agreement Stato-Regioni concerning the definition of some initiatives to promote the safe management of radioactive wastes and to select a site for the national repository, an Expert Group composed by 7 members, designed by the Ministries of Industry, Environment and Health as well as by Piedmont, Venetia, Emily-Romagna and Tuscany Regions, prepared a report on 'Conditions for a safe management of radioactive wastes'. Technical problems connected with the setting of clearance levels for all radionuclides of interest must be solved through a specific legislative document taking into account the debate that is developing at European Community and other International institutions and regulatory bodies. The major point to be solved for the decommissioning activities in which Italy is deeply committed is the siting of a national repository for radioactive wastes that should be at the same time an ultimate repository for wastes of categories I and II and a temporary repository for spent fuel elements and wastes of category III. Having solved this problem, the repository must be built and commissioned approximately by 2010, to maintain the objective sets in the 'Strategic Directions' document of the Ministry of Productive Activities to have the unrestricted release of the sites where the four Italian nuclear power plants are located approximately by 2020. Also in Italy one main issue in all these problems is how to build a public consensus. As it is now done in all countries with democratic representative systems, such decision processes cannot be done without an involvement of stakeholders, starting from local communities. There are not realistic and rational shortcuts to this procedure as already been seen in many countries and also in our own country. Italy has not yet a general legislation seeking stakeholders and more specifically public participation in the decision aiding process, then an administrative solution must be found. One possibility is to try to follow the recommendations of the Expert Group set up by the Conferenza Stato-Regioni. Probably this means that the time scale foreseen in the Decree of last December is unrealistic but not any more time must be wasted. In the meantime all the activities concerning the treatment and conditioning of radioactive wastes and dry storage of spent fuel must be considered as primary activities and carried out in a time as short as possible

[en] The Ginzburg-Landau equations are solved for d>=xi(T), where d is the film thickness and xi(T) the coherence length, so that the parallel critical fields for first kind superconducting films can be calculated. Finally a comparison is given between the theoretical values for Hsub(cF), as a function of temperature and specimen thickness, and the existing experimental data in the intermediate thickness range. (Auth.)

No abstract available