[en] As potential incidents in which the reactor protection system should operate but in which control rods are not inserted, ATWS involve an imbalance between the power generated and that extracted and if the core power is not reduced in a short time, a severe damage scenario is reached. Changes in regulations as made at the beginning of the 80s include specific requisites for each type of reactor. (Author)

[en] Due to the reduced number of plants and the wide variety of designs, until now Trend and Pattern Analysis has not been performed in a systematic bases. However considering the importance of operating experience feedback and other application, several actions are being initiated in this field by the Regulatory Body in Spain. This paper describes the recent actions taken in this direction, a new Safety Guide related with Reportable Events has been developed and also a new Group of Specialists to deal exclusively with Operating Experiences is expected to be operative in the near future

[en] Following the approval of the national reports, drawn up in the wake of the Fukushima Daiichi accident, the European Union decided to validate them by means of the peer review procedure, as a result of which groups of experts from different countries analysed them in situ in order to verify their accuracy. (Author)

[en] The Spanish nuclear regulatory agency, Consejo de Seguridad Nuclear (CSN), like most nuclear regulatory agencies and utilities, regularly conducts and participates in emergency drills. These drills refine the procedures, methods, and communication pathways necessary to support an emergency situation. During the drills, the plant conditions that may exist, the systems available, and the evolving plant conditions are initially unknown to the participants. They must be able to analyze the (simulated) plant data and respond with the proper actions to recover from the accident state. Given the limited plant data transmitted, assimilation of the information and interpretation of the evolving accident state is difficult. The MAAP Accident Response System (MARS) provides the CSN emergency response team with a means of evaluating, interpreting, and tracking the integral plant response using only the standard information about the current plant conditions. Moreover, potential future plant states, including possible operator actions, can be examined using the near-term, faster than real time, MARS predictor function. This paper summarizes how MARS can be used to assist the CSN staff

[en] This paper describes the overall licensing process in Spain, focusing on the initial commissioning requirements. The significance of this part of the regulatory work is evident both from the licensing and the licensee's points of view. Licensing in Spain is ruled by different laws which determine the general requirements and fix the licensing frame. Being a nuclear technology importer country, the base of the regulatory work lies on the rules and regulations of the country of origin of the planet, with the addition of case specific requirements. The application of this methodology to plants designed in different countries produces licensing processes which are similar to the overall, but very different in its development. It also means a special technical effort on the part of the regulatory body to cope with the problems arising from the use of different technologies and safety standards. The start-up programs from fuel loading to full power of a Westinghouse plant (Vandellos 2) and a Siemens-KWU plant (Trillo 1) are compared from the technical point of view, enhancing the differences that can be relevant for the regulatory work. The difficulties arising from the application of both the German and US concepts are discussed. (orig.)

[en] The general licensing process in Spain is described and details are given of initial commissioning programme requirements, the importance of which is obvious both from the point of view of licensing and of the plant. The licensing process is regulated in Spain by various laws which lay down fundamental requirements. In the case of a country which is importing nuclear technology, the regulations of the country of origin of the project form the basis of the licensing process, and to these are added specific requirements in each case. The application of this methodology to plants designed in various countries leads to licensing processes which are similar but which nevertheless develop in very different ways, and this entails a considerable technical effort on the part of the regulatory body. One Westinghouse PWR plant (Vandellos-2) and one KWU PWR plant (Trillo-1) have been connected to the grid recently, and their commissioning programmes can be compared from a technical point of view. Emphasis is placed on such questions as differences which are important for licensing work, standardization of the commissioning programme, participation of the main supplier in implementation of the programme, organization of plant personnel, and so on. (author). 2 figs

[en] In March 2011 the European Council requested that the ENSREG and the Commission carry out assessments of all nuclear power plants in Europe. Stress Tests and Peer Review were conducted by operators, national regulators and regulatory peers and a final Peer Review report was prepared in April 2012. ENSREG approved the Peer Review report and the recommendations in a joint statement dated 26 April 2012, which concluded that follow-up activities would occur through an Action Plan. The Action Plan, to be developed by each National Regulator will assist in demonstrating that the learning from the Stress Tests and their Peer Review will result in improvements in safety across European Nuclear Power Plants. It will ensure that the recommendations and suggestions from the Peer Review process will be addressed by national regulators and ENSREG in a consistent manner. The National Action Plan will be based on the Peer Review approach as much as practicable. According the terms of reference approved by ENSREG each national regulator developed the National Action Plan (NAcP) identifying the regulator actions ensuring national improvements in their nuclear industry, which were identified following the Fukushima Accident, focusing on the NPPs, and within the terms of reference of ENSREG. The NAcPs are structured according to the six topics of the 2nd Extraordinary Meeting of the CNS covering these topics as appropriate. The objective of the National Action Plan is to promote the role of Europe in setting standards for world-wide nuclear safety through continuous improvement, showing a clear commitment to openness and transparency. The content of the National Action Plan will also take account of relevant output from the extraordinary meeting of the Convention for Nuclear Safety (CNS), and be provided by the end of 2012 and made publicly available on the ENSREG web site. Each National Action Plans (NAcPs) describe the actions, identified following the Fukushima Dai-ichi accident, that were taken, planned or implemented and their schedule to improve the safety of European nuclear power plants (NPPs). The National Action Plan provides an update on the following: (a) National regulator conclusions from the Stress Test report; (b) Recommendations in the Country Peer Review report; (c) Recommendations in the final Peer Review report; (d) Additional recommendations arising from the CNS; and (e) Additional activities derived from national reviews and related decisions. (author)

[en] The CSN has been assigned with several functions in the management of nuclear or radiologic emergencies, such as the technical assessment to the authorities for the decision making on the forgoing steps and measures. The article describes the emergency reply organization prepared by the CSN with the description of a practical example: the tracking from the SALEM of an internal emergency rehearsal in the Asco nuclear power station. (Author) 6 refs