Nuclear safety management

The management of nuclear safety is framed within the Integrated Management System implemented by the Iberdrola Generación Nuclear, which comprises its own manuals and development procedures, in compliance with the S 19 Requirement of the Consejo de Seguridad Nuclear (Nuclear Safety Council), based on the document “Safety Requirements nº GS-R-3: The Management System for Facilities and Activities” of the International Atomic Energy Agency (IAEA) and its applicable documentation (GS-G-3.1 “Application of the Management System for facilities and Activities” and DS349 “Application of the Management System for Nuclear Facilities” safety guides).

The concept of safety upheld by Iberdrola Generación Nuclear integrates all safety-related  concerns, including nuclear safety, radiological protection, security of facilities and nuclear material, and the prevention of occupational risks, and is based on a "continuous improvement cycle" applicable to all management areas (safety, security, environment, economics, etc).

  • While carrying out these processes, it is important to highlight some relevant aspects:

    • Strict compliance with legislation which regulates the exploitation of nuclear plants, such as laws (Nuclear Energy, Establishment of the Consejo de Seguridad Nuclear, etc.), regulations (Health Protection against Ionising Radiation, Nuclear and Radioactive Facilities, etc.) and directives (Nuclear Safety, etc.).This legislation is applied to the plants mainly through official documentation related to exploitation (Safety Studies, Operational Regulations, Technical Operating Specifications, Internal Emergency Plan, Quality Assurance Manual, Radiological Protection Manual, Manual for Calculating External Emissions, Service Inspection Manual, Operational Limits of the Core, Fire Safety Manual, Technical Specifications, and the Operational Requirements Manual).

      These types of documents are included in the first level of requirements reflected in the Iberdrola Generación Nuclear. Authorization for the Exploitation of Nuclear Plants. Specifications related with licences, manuals and administrative procedures, design specifications, technical procedures and manuals, etc., also apply.Other complementary aspects related with safety, such as product guarantee, quality and conditions for client supply, are detailed in the quality manuals, which set forth the appropriate orientation of the process in order to minimize operational risks and stimulate the supply of a competitively priced, safe, reliable and environmentally-friendly product.
    • The competent regulatory body in Spain with regard to nuclear safety and radiological protection, the Consejo de Seguridad Nuclear (Nuclear Safety Council), dictates rules and instructions, inspects, supervises and controls the operations of nuclear plants, and grants authorisations and licences.This is an autonomous, independent entity which is held responsible by the National Parliament and informs the public about its activities and the exploitation of plants.

      To this end, it assigns two on-site inspectors to each plant, who work full-time and exclusively at the facility to which they are appointed. In this task of regulatory control, the Nuclear Generation Division collaborates actively in supplying required information and allowing access to software applications, databases, documentation and records related to exploitation, as is the case with the direct and unrestricted access to the nuclear plant corrective actions programme.


  • Plannig

    The first aspect of safety management implies planning. This planning must consider different time frames (long, medium and short terms):

    • Long term: this is achieved through policies and directives and a management plan.
    • Medium term: this is done through setting objectives, allocating budgets and designing plans (investment, refuelling, etc.).
    • Short term: this is accomplished through daily planning of operations and follow-up of established goals.


    The second aspect of safety management is execution. This is based on the effectuation of different processes, which may be grouped into the following types:

    • Strategic: management of the surroundings and regulation, definition and creation of strategies.
    • Productive: administration of generation assets, production of electric power, and management of fuels.
    • Supportive: management of economic-financial resources, rendering of logistical and general services, management of human resources and information technologies

    An indispensable tool for the management of safety and radiological protection is the periodical follow-up of operational indicatorscollected by the control panel, each one reflecting goals which are set annually and which are conservatively linked to the continuous improvement of operational and management-related parameters and the mid and long term objectives. The Nuclear Generation Division has established a methodology for defining operational indicators used in the evaluation of the most important parameters related with processes, product and safety. The appropriate degree of follow-up or measurement is chosen for each of the established processes in relation to its impact on conformity with the particular and specific requirements of each.

    The status of the operational indicators and degree of attainment of the  goals is part of the information included in the management review of the Integrated Management System. At Iberdrola Generación Nuclear, the relation between indicator and commitment is quite direct.

    • Training on numerous relevant aspects, such as safety culture, radiological protection and plant operations, using tools such as the full spectrum simulator, specific to each plant, where personnel with operating licences are trained within a time period considerably longer than that required by the Consejo de Seguridad Nuclear (Nuclear Safety Council). Control room personnel hold an operations licence granted by the Consejo de Seguridad Nuclear (Nuclear Safety Council) (renewable every six years), upon completion of a lengthy training period and passing of corresponding examinations (theoretical, simulator and on-site).
    • Use of operating experience, both external and internal. This analysis derives aspects as important as corrective actions (which may engender improvements to procedures, modifications to design or other organizational or supervision-related improvements), lessons learned (which may engender improvements in the training programme for licensed or other type of personnel), or the trends analysis, which may lead to an exchange of experiences amongst different plants. External operational experience is mainly channelled through the analysis of documentation of international scope remitted by the INPO —Institute of Nuclear Power Operations— and WANO —World Association of Nuclear Operator— (significant event report, significant operating experience reports, operating plant experiences) and the evaluation of their applicability to Iberdrola Generación Nuclear nuclear plants. In this regard, Iberdrola Generación Nuclear is a member of WANO, and assumes all the rights and obligations implied thereby. In the specific realm of operational experience, Iberdrola Generación Nuclear receives pertinent information from WANO for its analysis, and remits relevant experiences back to WANO for their diffusion amongst WANO members. Likewise, WANO verifies during its periodical evaluations of plants (peer reviews) that the operational experiences received and better management practices have been properly analyzed and implemented.


    The third aspect of safety management is evaluation. It allows for verifying that compliance with the specified requirements for plant operations is correct and is capable of identifying possible deficiencies and opportunities for improvement which will result in greater operational safety and efficiency.


    The fourth aspect of nuclear safety management implies the management of:

    • Preventive and corrective actions. 
    • Actions for improvement.

    A process which entails the following characteristics is established through the corrective actions programme:

    • An integrated process which includes the identification, evaluation, and resolution of real or potential non-conformities, as well as proposals for improvement upon the verification of the effectiveness of committed actions. The identification of possible non-conformities or actions for improvement may result from a diversity of sources: external evaluations, independent internal evaluations, self-evaluations, findings made by personnel or discovered through routine activities.
    • It sets forth a system for categorizing non-conformities and for prioritizing actions in accordance with their relevance for safety.
    • It establishes mechanisms for identifying adverse trends and for evaluating the effectiveness of implemented actions.
  • Use of technical analysis tools, such as equipment reliability process, preventive and predictive maintenance, the risk monitor, the maintenance rule, and the probabilistic safety assessment, which help to optimize operations and reduce risks by identifying possible weaknesses which are improved or solved by means of design changes; this is applicable to all operating states of the plant: cold shutdown, hot shutdown, start-ups, low power operation and power operation.

    In order to minimize the likelihood of unplanned shutdowns and incidents and events and prevent recurrences, some programs and techniques are used. Structures, systems and components are either permanently or periodically monitored and tested, to make sure that they are either available or performing as expected. The operating experience program for both internal and external events analyzes hundreds of events per year and defines preventive actions as applicable, and the overall program performance is evaluate periodically by both the regulatory authority and peers from WANO or INPO. Right after any unplanned shutdown or event occurs, an immediate investigation is performed to look for corrective actions as needed, and subsequent root cause analysis and common cause analysis are made depending on the significance of the events to identify preventive actions. Several techniques can be used for these root cause analyses, among others, human performance enhancement system (HPES) and management oversight and risk tree (MORT). Long term trends and comparisons with industry performance are also analyzed to identify if long term improvement initiatives are needed.

    For further details on outcomes, please see the graphs in the nuclear indicators.

    Iberdrola Generación Nuclearis strict in its adherence to applicable legislation in addition to the requirements derived from official exploitation documentation, as indicated previously. Amongst these are highlighted, as a fundamental component of safety:

    • The Internal Emergency Plan which guarantees an adequate response during emergencies and which, along with the corresponding Provincial Emergency Plan for which governmental authorities and public protection bodies are responsible, make up the Integrated Emergency Plan for the purpose of attenuating the radiological and other types of consequences for the personnel at the plant, the population at large and the environment. The internal emergency plan follows the specific standard: it contains provisions for organizing and setting roles and functions, managing the facility to minimize damages, evacuation of workers, providing information to and coordination protocols with authorities, radiologically controlling the facility and the environs, performing periodic trials and drills, etc. This is what is considered adequate response and is evaluated continuously by the licensees and regulatory authorities through the SISC (Sistema de Evaluacion Integrada de Centrales), a system similar to the ROP (Reactor Oversight Process) in USA.
    • The Fire Protection Program for the purpose of preventing fires and mitigating the effects on workers, facilities and the general public of unlikely fires.

    Also, nuclear power plants are required to inform about several operational issues, for example the nature of incidents and events, to the Consejo de Seguridad Nuclear. You can access that information through the Consejo de Seguridad Nuclear External link, opens in new window. website.

  • The management of radiological protection is also framed within the integrated management system implemented by the Iberdrola Generación Nuclear.

    To this end, criteria for the protection of workers and members of the public against risks derived from ionising radiation are applied to all nuclear plant practices. Applicable legislation in Spain on radiological protection is the Regulations for Health Protection against Ionising Radiation contemplated in the most recent European Directives on this matter. Both national laws as well as European directives are founded upon principles and criteria set forth by the International Atomic Energy Agency (IAEA) and the International Commission on Radiological Protection (ICRP).

    The Nuclear Generation Division maintains a Radiological Protection Service at each nuclear plant for which the Service Manager (title granted by the Consejo de Seguridad Nuclear upon the successful passing of an examination) is responsible.

    The two basic radiation protection principles applicable to the operation of nuclear power plants are the limitation and the optimization of doses to workers and the public.

    The limitation principle is effectively achieved by a sound implementation of the optimization principle. Should an extremely improbable event occur where a dose limit is exceeded, there are provisions in the Radiation Protection Manual about how to manage the case.

    The optimization of the radiation protection of the workers and the public is achieved by continual implementation of the ALARA principle (as low as reasonably achievable). This principle can be stated as the process or method used to make a system of protection as effective as possible within the given criteria and constraints by considering how best to use resources in reducing radiation risks to individuals and populations as far as is reasonably achievable, social and economic factors being taken into account. For Iberdrola Generación Nuclear this is materialized in the ALARA Program, which results in Individual doses, number of persons exposed and probability of potential exposures are kept to the lowest minimum as reasonably feasible, taking into account socioeconomic factors; and the mode, magnitude and duration of interventions are optimized so that the results obtained from these are the best possible.

    The practical implementation of the ALARA Program is based in the following lines of action:

    • Integration of the dose reduction criteria in the routine management system.
    • Specific organizational arrangements to have all concerned people involved and coordinated in activities important to radiation protection.
    • Integration of radiation protection in job planning and execution and in the process of identification of design and working method improvements out from lessons learned.
    • Application of ALARA criteria to contractors activities.
    • Integration of radiation protection in training programs.
    • Consideration of ALARA criteria in the bidding process making contractors accountable for the effective implementation of committed action.

    Radiological protection of nuclear plants is developed through identifying and controlling radiological risks, classifying workers and members of the public, implementing radiological surveillance programmes, classifying and signalling areas, and applying basic strategies and principles for action as indicated above. The rules for action and operations are presented in the radiological protection manuals and the technical and administrative developmental procedures. This documentation reflects the dose limits for both the general public and workers, and the protocols to be strictly complied with and controlled.

    For any radiological magnitude or parameter (dose, radiation rate, airborne or surface contamination, etc.) three reference levels exist whose values and actions are prescribed in the Radiological Protection Manual: reporting, investigation and intervention.This conceptual grading scheme stems from international standards.

    In addition, Iberdrola Generación Nuclear sets its own voluntary management reference levels and controls, which relate to:

    • Individual and collective occupational doses by making estimations and setting objectives at lower values than estimations to stimulate improvements, both for periods of time and for specific jobs.
    • Public doses optimization via liquid and gaseous effluents control and minimization: effluents activity releases are monitored on line and corrective actions are taken upon deviation from expected values, and processes improvement actions are considered in the medium and long term as well, such as processes adjustments or design modifications.

    Operational, functional and measuring systems and equipment used at Iberdrola generación Nuclear nuclear plants in different processes related with safety and radiological protection are considered to be technologically state-of-the-art internationally, and have levels of precision and accuracy which are more rigorous than those required by either legislation or the regulating body.

    The quality assurance programme, independent of operational hierarchies and responsible only unto the nuclear plant divisions, guarantees the proper design of follow-up, documentation, registration and control of safety and processes and tasks related with radiological protection indicated in this document.

    All these programs, provisions, management systems, monitoring devices and references levels, described above allow Iberdrola Generación Nuclear to have a robust system for:

    • Assessing, monitoring and auditing performance.
    • Detecting, correcting deviations and preventing reoccurrences.
    • Following-up on the effectiveness of corrective, preventive and improvement measures.
    • Maintaining the system updated and fed back with lessons learned and operating experience.

    For further details on outcomes, please see the graphs in the nuclear indicators.