The security of nuclear facilities and nuclear material is meant to prevent the compromise of nuclear safety through unauthorised actions, the intentional release of radioactive materials into the environment and the theft of nuclear materials. To this end, all Swiss nuclear power plants have a special security dispositive. As with safety, the principle of security is based on profound protection through structural, technical, organisatorial, personal and administrative measures.
The reactor pressure vessel is enclosed by the containment as the third barrier. This consists of a steel primary containment and a concrete secondary containment.
With its pipelines, shut-off valves and other components, the cooling circuit, together with the reactor pressure vessel, is the second barrier for trapping radioactive substances
The reactor pressure vessel, together with the water’s cooling circuit, is the second barrier for trapping radioactive substances.
The fuel pellets are filled into metal tubes. Together with the nuclear fuel matrix, the cladding tubes are the first barrier for trapping radioactive substances in nuclear power plants.
The nuclear fuel is pressed into pellets and compacted using the sintering process before use in nuclear power plants. This process transforms the nuclear fuel into a ceramic material, which is able to retain the fission products that arise during operation in the nuclear fuel matrix.
The barrier concept aims to trap sources of radiation in nuclear facilities across several levels. Similar to the layers of an onion, independent barriers ensure that the risk from sources of radiation are minimised for people and the environment.
The protection of nuclear installations and nuclear materials against sabotage, violent actions or theft has to be based on an in-depth defence system which involves structural, technical, organisational, personnel and administrative measures.
HRA, Human Reliability Analysis: the HRA project examines the reliability of human actions, taking account of various boundary conditions. The state of the art is the determination of failure probabilities for actions that are required during an incident, but are not performed. On the other hand, there is no efficient method for the systematic identification […]