«Nuclear power plants are among the most robust industrial constructions in Switzerland. We ensure that operators constantly question the safety of their installations, calculate any residual risk using the latest methods and constantly improve the resilience of the installations with targeted upgrading. ENSI’s requirements with regard to earthquake safety, for instance, are considered to be among the most progressive and the most strict throughout the whole world.»
Stefan Brosi, specialist for safety analyses
Safety analyses are of importance in many areas of supervision. ENSI uses them to test the safety of nuclear installations, including the design of all systems and components, including fuel assemblies.
The experts of the Safety Analyses department continually evaluate installations in normal operation and devote themselves to the modelling, forecasting and diagnosis of abnormal occurrences in order to establish the best possible safety standards. Their work is based on the latest methods and models that adequate describing the behaviour of a nuclear installation.
The specialist sections involved actively follow the state of the art, both nationally and worldwide, cultivate an intensive exchange of information on expert committees and support scientific research. They integrate relevant innovations into the body of rules for Swiss nuclear installations by issuing guidelines.
When operators wish to make modifications to their nuclear installations ENSI security experts review the steps being planned on the basis of national and international bodies of rules and evaluate them with their own simulation models, e.g. in relation to their risk relevance or thermohydraulic consequences. The review takes account of the components in an installation such as pumps, pipes and instruments, but also of actions and processes, with the involvement of NPP personnel.