In designing a nuclear facility a comprehensive safety analysis is carried out to identify all sources of exposure and to evaluate radiation doses that could be received by workers and the public, as well as the potential impact the facility can have on the environment. Every event sequence, including those originated by extreme external phenomena, that may lead to an accident is examined in the safety analysis, and the results are used as the basis for designing emergency arrangements, which include:

• Designing and ensuring full operability of the safety system installed to mitigate accidental sequences leading to uncontrolled releases of radio­active material to the environment or producing damage to the plant and the unwanted exposure of its personnel

• Implementing adequate operational procedures to lead the plant to safe conditions after any accident or malicious acts that can seriously damage reactivity control systems, cooling systems or confinement of radioactive material systems

• Implementing a training programme to ensure that all personnel have adequate skills to manage any crisis generated by any situation that can lead to an emergency situation.

During plant operation emergency preparedness activities are focused on maintaining and improving the capacity to manage any emergency situ­ation. These include: [9]

• Conducting an adequate drill and exercise programme to validate, train and enhance the emergency plans and procedures.