Kärnkraftanläggningar. Säkerhet

This document applies to nuclear power plants with water cooled reactors and, in particular, to the design of components and civil structures against seismic events in order to meet the safety objectives.
For other nuclear facilities the applicability of the document must be checked in advance, before it might be applied correspondingly. Seismic isolation is not adressed in ISO 4917.
The following safety objectives are defined in order to assure the protection of people and the environment against radiation risks.
a) controlling reactivity,
b) cooling fuel assemblies,
c) confining radioactive substances, and
d) limiting radiation exposure.

This document applies to civil structures of nuclear power plants with water cooled reactors in order to achieve the safety objectives specified in ISO 4917-1. For other nuclear facilities the applicability of the
document needs to be checked in advance, before it might be applied correspondingly.
This document specifies the requirements for civil structures that must be met for the verification of their load-bearing capacity in case of a seismic event. Additionally, requirements are specified pertaining to the verification of the serviceability of civil structures as far as necessary for maintaining
their safety-related function in case of a seismic event (e.g., deformation and crack-width limitations).
This document will be applied under the presumption that the geology and tectonics of the plant site has been investigated with special emphasis on the existence of active geological faults and lasting geological ground displacements, and that the site has been deemed suitable for a nuclear installation.
To achieve these goals, this document deals with the requirements specific to the seismic design of civil structures above and beyond their conventional design. The basic requirements of these precautionary
measures are dealt with in ISO 4917-1.
This document does not apply to cranes, to detachment devices for lifting equipment nor to the supporting and mounting constructions of components.
This document is independent of national standards. Recommendations, given in Annex A, are mainly based on the Eurocodes-Design-Philosophy and European standards. Alternatively other equivalent standards or regulations can be used in case the general requirements given in this document can be met.
NOTE The term civil structures as used in this document shall comprise buildings and structural members made of reinforced concrete, pre-stressed concrete, steel, as well as steel composite structures and masonry.
Among others, these include the containment, crane runways, platforms, anchor constructions and canals.

This document applies to nuclear power plants with water cooled reactors. For other nuclear facilities the applicability of the document might be possible but should be checked in advance.
This document specifies the requirements for the earthquake safety of components. The operationspecific safety-related requirements for each component – e.g., load-bearing capacity (stability),
integrity and functionality (see 4.1) are not the subject of this document. With regard to analyzing the mechanical behavior of the individual components and verifying the fulfillment of their safety related functions, additionally, the respective component-specific standards need to be consulted.
In this document, the term mechanical components refers to components such as vessels, heat exchangers, pumps, valves, lifting gear, distribution systems and pipe lines including their support
structures in as far as these components are not considered to be civil structures in accordance with ISO 4917-3. Liners, crane runways, platforms and scaffoldings are not considered as being part of these mechanical components.
In this document, the term electrical components refers to the combination of electrical devices including all electrical connections and their support structures (e.g., cabinets, frames, consoles, brackets, suspensions or supports).
NOTE This document is independent of national standards. Recommendations, given in Annex A, are mainly based on the Eurocodes-Design-Philosophy and European Standards. Alternatively other equivalent standards or regulations can be used in case the general requirements given in this document together with Annex A can be met.

The document applies to nuclear power plants with water cooled reactors.
The present document does not apply to earthquakes stronger than the design basis earthquake.
This document specifies guidance on the actions to be taken in preparation for and following an earthquake at a nuclear power plant. This document is intended to be used as a guideline for decision making regarding continued operation, shutting down and restarting the plant after an earthquake. It
can also be used to assist operating organizations in the preparation and implementation of an overall pre- and post-earthquake action programme for dealing with situations in accordance with the level of seismic ground motion experienced at the site and the seismic design level of the plant.