Background articles

Development and Research Work in the Field of Radiation Measurement Technology: this project deals with the verification and calibration of dosimetry systems and radiation measurement instruments. On the one hand, importance attaches to personal dosimetry, i.e. the measurement of the outer and inner radiation exposure for people. This field also covers measurements of the release […]

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OECD MCCI, Melt Coolability and Concrete Interaction: the OECD MCCI (Melt Coolability and Concrete Interaction) project concerns severe accidents in which the reactor core melts due to the absence of cooling, after which the reactor pressure vessel (RPV) also fails. In the reactor building, the corium reaches the concrete foundation, which should be prevented from […]

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Im August 1955 nahmen Forscher auf dem Gelände des Eidgenössischen Instituts für Reaktorforschung (EIR) in Würenlingen (AG) den „Diorit“-Reaktor in Betrieb.

OECD CABRI Waterloop Project: experiments on the high burn-up behaviour of fuel rods in case of rapid reactivity incidents were carried out on the CABRI research reactor in Cadarache, France. These incidents occur when the reactor briefly becomes over-critical due to the rapid, uncontrolled movement of a control element or control rod. The project is […]

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Feasibility Study for Non-Destructive Measurements on the Steel Pressure Shell of the Primary Containment of Nuclear Power Plants: the primary circuit, including the reactor pressure vessel, is enclosed by a steel pressure shell as part of the defence-in-depth safety barriers. Depending on the structural design of the nuclear power plant, this is directly surrounded by […]

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PISA, Pressure Vessel Integrity and Safety Analysis: in connection with the long-term operation of the Swiss nuclear power plants, it must be proven that the integrity of the reactor pressure vessel (RPV) continues to be guaranteed during normal operation and also in case of operating faults and postulated incidents. The PISA project was launched in […]

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Nine months after the disaster at the Fukushima nuclear power plant, Japan is working to contain radiation exposure in the region of the accident. The challenges confronting the country in this endeavour are shown by the new ENSI report on the radiological effects of the accident on 11 March 2011. ENSI already deduced some “Lessons learned for Swiss radiation protection” at the end of October.

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The analysis of the accidents at Fukushima confirms that Swiss nuclear plants are safe. However, the Swiss Federal Nuclear Safety Inspectorate (ENSI) has identified a variety of findings (Lessons Learned) from Fukushima which should now be utilised to continue optimising the safety of Switzerland’s nuclear power plants. All the measures that need to be implemented on the basis of these findings should be in place by 2015.

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Aufräumarbeiten Fukushima

Inadequate technical design against tsunamis was indisputably a key factor in the accident at the Fukushima Dai-ichi nuclear plants on 11 March 2011. In order to understand the scope and complexity of the event, an interdisciplinary analysis team was formed at ENSI. Its members include (for example) experts in the fields of people and organisation, […]

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During the two-week IRRS mission, the IAEA experts will investigate how ENSI performs its supervisory duties. To ensure that this scrutiny of ENSI is conducted in an orderly and systematic manner, the IAEA has developed a list containing about 2000 questions. The mission’s objective is to investigate the extent to which ENSI applies the safety […]

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