Federal Nuclear Safety Inspectorate

Federal Nuclear Safety Inspectorate

Headquarters	Brugg AG, SwitzerlandSwitzerland
Chief	Marc Kenzelmann
Employees	about 140
At sight	ENSI Council
Website	www.ensi.ch

The Swiss Federal Nuclear Safety Inspectorate (ENSI; French Inspection fédérale de la sécurité nucléaire , IFSN ) is Switzerland's supervisory authority for nuclear safety and security of nuclear facilities ; It oversees the Beznau , Gösgen , Leibstadt and Mühleberg nuclear power plants , the research reactors of the Paul Scherrer Institute , the University of Basel and the ETH Lausanne as well as the Swiss “interim storage facility for radioactive waste” Zwilag . ENSI is based in Brugg in the canton of Aargau .

In turn, ENSI is monitored by the ENSI Council , a body elected by the Swiss Federal Council and directly subordinate to it (5 to 7 members).

history

Until the end of 2008, the main department for the safety of nuclear facilities (HSK) was the technical supervisory authority responsible for nuclear facilities in Switzerland. It was based in Würenlingen in the Canton of Aargau .

The HSK checked the safety of the five operated nuclear power plants and the other nuclear facilities in Switzerland. The HSK also performed the function of radiation protection supervision for all nuclear facilities as well as tasks in the area of the interim and final storage of radioactive waste . In contrast to Germany , where the above-mentioned functions are separated and in some cases even carried out at the state level, the HSK performed the tasks under a joint management umbrella. It was checked by the Commission for the Safety of Nuclear Installations (KSA), which consists of part-time experts .

ENSI has been performing these tasks since January 1, 2009. According to a parliamentary resolution, the HSK was separated from the Federal Office of Energy and converted into an independent supervisory authority. This implements the requirement of the international convention on nuclear safety with regard to the independence of the supervisory authority.

Legal basis

The organization of ENSI is regulated in the ENSI Act (ENSIG). The legal basis for the supervisory activities of ENSI can be found mainly in the Nuclear Energy Act (KEG) and the Radiation Protection Act (StSG).

The tasks of ENSI

According to the Nuclear Energy Act, the operator is responsible for the safety of his system. ENSI checks whether the operator is fulfilling this responsibility and uses its own analyzes, inspections and supervisory discussions to create its own assessment basis.

ENSI's supervisory activities can be divided into the two main tasks of plant assessment and operational monitoring:

Plant assessment

Basics and guidelines

The assessment and monitoring of nuclear installations is based on laws, guidelines and technical and scientific principles. It shows the safety requirements and the criteria on which the ENSI assessment is based. The principles and guidelines are further developed by ENSI in line with the state of science and technology. To this end, ENSI promotes nuclear safety research, is represented in over 70 international commissions and specialist groups for the safety of nuclear energy and is involved in the further development of international safety requirements. In the guidelines, among other things, radiation protection goals for the operation of nuclear facilities are specified, reporting on the operation or organization of nuclear power plants is regulated and the requirements for deep geological disposal are specified.

Assessment

ENSI prepares safety reports when operators of nuclear installations submit applications that go beyond the existing operating license. For example, the periodic safety reviews of all nuclear power plants are assessed by ENSI and the results are recorded with conditions in an expert report.

Approvals

Applications for changes to nuclear installations that are covered by existing operating licenses are handled by ENSI and, if the decision is positive, issues a release. Examples of this are changes to components and systems classified in terms of safety or changes to technical specifications.

Operational monitoring

Control, inspection and approval

ENSI checks the operator's reports, conducts supervisory discussions and controls the nuclear facilities, including their organization and operation, through on-site inspections. ENSI only allows people who have the necessary skills and training for safety-relevant positions in nuclear installations.

Revision

Every nuclear power plant carries out an annual inspection lasting several weeks, during which maintenance work and repairs are carried out in the plant. At the same time the fuel is renewed. These inspection shutdowns of the nuclear power plants are accompanied and monitored by ENSI.

Radiation monitoring

ENSI monitors compliance with radiation protection regulations and dose limits. It controls the radioactivity emissions from the nuclear facilities and compliance with the emission limits. It determines the radiation exposure of the population and the plant personnel.

Remote monitoring and forecasting

Around every nuclear installation, ENSI operates a measuring system for automatic dose rate monitoring as well as a system for transmitting installation parameters from the nuclear power plants. The data enable ENSI to make prognoses for the possible spread of radioactivity in the area in the event of an incident.

Incident handling

Incidents in Swiss and foreign nuclear facilities are systematically evaluated with regard to their significance for nuclear safety. The assessment of the measures taken by the operator checks whether the findings can be transferred to other nuclear facilities in Switzerland. If necessary, ENSI calls for improvements.

Emergency readiness

ENSI is part of a nationwide organization for dealing with serious incidents, which includes the National Alarm Center.

Security assessment

ENSI summarizes all data accumulating over the course of a year in a safety assessment. From this, it derives any measures and its future supervisory planning. In annual reports on the safety of the nuclear facilities, radiation protection and the experience gained from operations and research, ENSI reports to the public.

Analyzes after the reactor accident in Fukushima

After the Fukushima nuclear disaster , ENSI analyzed the events with an interdisciplinary team of experts. The results, including the lessons learned, were presented to the public in four reports between August and December 2011.

After Fukushima, the Swiss nuclear power plants also had to prove that they could handle a 10,000-year flood as well as a 10,000-year earthquake and an earthquake-related flood. Switzerland also participated voluntarily in the EU stress test. As a result of these reviews, the Swiss nuclear power plants had to take various improvement measures.

Years of operation

Year of operation 2009

In 2009, the Swiss nuclear installations recorded 24 reportable incidents. Of these, eleven occurred in the two reactors of the Beznau nuclear power plant , four in Mühleberg , three in Gösgen and four in Leibstadt . There are also two incidents in the PSI's core facilities. The incident in Beznau on August 3, 2009 was assigned to level 2 on the international INES event scale, the delayed incident in Gösgen of June 24, 2008 to level 1 and the other incidents in the reporting year were assigned to level 0. Since at least 1995 this has been the worst operating year for the Swiss NPP park in terms of such incidents.

Operating year 2010

The 41 reportable incidents in 2010 are distributed among the Swiss nuclear facilities as follows: a total of ten times for the two reactors in the Beznau nuclear power plant , eleven times for Gösgen , five times for Leibstadt and fourteen times for Mühleberg . In the Mühleberg case, ENSI puts into perspective that the malfunctions "essentially" occurred during the commissioning of new equipment. In 2010, two reportable incidents of INES level 0 occurred in PSI's nuclear facilities. ENSI did not record any incidents at the two research reactors at the ETH Lausanne and the University of Basel. 40 of the 41 incidents can be assigned to INES level 0. ENSI assigned an incident during the overhaul at the Leibstadt nuclear power plant on August 31, 2010 to INES level 2. The permissible radiation dose of 20 millisievert (mSv) per year was exceeded in one diver. However, the incident did not result in a violation of the Radiation Protection Act.

Operating year 2011

In 2011 there were 31 reportable incidents in Swiss nuclear power plants. Of these, 30 were assigned to level 0 and one to level 1 of the INES event scale. Seven incidents concerned the Beznau nuclear power plant with units 1 and 2; five incidents concerned Gösgen , eleven the Leibstadt nuclear power plant , four the Mühleberg nuclear power plant , three the nuclear facilities of the Paul Scherrer Institute and one the research reactor of the ETH Lausanne. ENSI recorded no incidents at ZWILAG or the research reactor at the University of Basel . The INES-1 event was reported as a result of a possible blockage of the emergency system water intake during an extreme flood at the Mühleberg nuclear power plant. This realization prompted the power plant operator BKW-FMB Energie AG to shut down and retrofit the system before the planned overhaul date.

Operating year 2012

In 2012 there were 36 reportable incidents in Swiss nuclear installations. 14 concerned the two units of the Beznau nuclear power plant ; nine the Gösgen nuclear power plant , five the Leibstadt nuclear power plant , six the Mühleberg nuclear power plant and two the PSI nuclear facilities. ENSI recorded no reportable incidents at the Würenlingen ZWILAG central interim storage facility, at the research reactor at the ETH Lausanne or at the research reactor at the University of Basel. The reportable incidents included four reactor shutdowns: one each in the Mühleberg and Gösgen nuclear power plants and two in the Beznau nuclear power plant. ENSI assigned an incident in 2012 to level 1 on the international INES event scale, which ranges from 0 to 7. It concerned a malfunction in Unit 2 of the Beznau nuclear power plant: During a periodic function test of the emergency diesel generator, it did not start. The unit was started with compressed air, but did not ignite. The specialist staff deployed at the plant vented the fuel supply line. During the next attempt to start the unit started up. All other incidents during the year were below the INES event scale, i.e. at level 0.

Operating year 2013

The number of reportable incidents that are relevant for nuclear safety was 37 reports, which fluctuated over the previous years. Two incidents concerned the Beznau NPP Unit 1 and five concerned the Beznau NPP Unit 2; seven incidents concerned the Gösgen NPP, seven also affected the Leibstadt NPP, 13 the Mühleberg NPP, two the PSI nuclear facilities and one the research reactor at the University of Basel. ENSI recorded no incidents at the central interim storage facility in Würenlingen or at the research reactor at the ETH Lausanne. On the international INES event scale, which ranges from 0 to 7, ENSI assigned all reportable incidents in nuclear power plants to 0 in the year under review. In 2013, ENSI also carried out over 460 inspections.

Operating year 2014

In 2014 there were 39 reportable incidents in Swiss nuclear installations. Five incidents related to the Beznau NPP unit 1 and five related to the Beznau NPP unit 2; eleven incidents concerned the Gösgen NPP, nine the Leibstadt NPP and eight the Mühleberg NPP. The nuclear facilities of PSI, the central interim storage facility in Würenlingen and the ETH Lausanne reported no incidents. The research reactor at the University of Basel recorded an incident. On the international INES event scale, which ranges from 0 to 7, ENSI assigned 38 reportable incidents in the nuclear power plants to level 0 in the reporting year. One incident in Leibstadt was classified as INES-1. According to ENSI, there has only rarely been damage to fuel rods in Swiss nuclear power plants in recent years.

Operating year 2015

In 2015 there were 34 reportable incidents in Swiss nuclear installations. Four incidents related to the Beznau NPP unit 1 and three to the Beznau NPP unit 2; ten incidents concerned the Gösgen NPP, ten the Leibstadt NPP and seven the Mühleberg NPP. The PSI's nuclear facilities reported four incidents, none of the central interim storage facility in Würenlingen and the University of Basel. The research reactor at the ETH Lausanne recorded an incident. On the international INES event scale, which ranges from 0 to 7, ENSI assigned 32 reportable incidents in the nuclear power plants to level 0 in the year under review. One incident in Leibstadt and one in Gösgen was classified as INES-1. An incident in Beznau 1 cannot yet be classified.

Operating year 2016

In 2016, Swiss nuclear installations recorded 31 reportable incidents. Of these, seven occurred in the two reactors of the Beznau nuclear power plant , three in Mühleberg , twelve in Gösgen and nine in Leibstadt . No incidents were reported from the Paul Scherrer Institute PSI, the central interim storage facility in Zwilag and the research reactors.

Year of operation 2017

The number of reportable events in 2017 was 29. Three incidents related to the Mühleberg nuclear power plant, nine to the Leibstadt nuclear power plant, six to the Gösgen nuclear power plant, three to Unit 1 of the Beznau nuclear power plant, four to Unit 2 and one incident related to both units of the Beznau nuclear power plant . An incident occurred in the central interim storage facility in Zwilag. All incidents in the 2017 operating year were assigned to level INES 0. No incidents occurred in the Paul Scherrer Institute PSI or in the research reactor of the Swiss Federal Institute of Technology in Lausanne EPFL.

Operating year 2018

The number of reportable incidents at the five nuclear power plants is 33 reports, in the range of the long-term average. Three incidents concerned the Beznau 1 NPP, one incident concerned the Beznau 2 NPP, 13 incidents concerned the Gösgen NPP, 12 incidents concerned the Leibstadt NPP, four incidents concerned the Mühleberg NPP. For the remaining nuclear facilities, five incidents related to the PSI nuclear facilities, one of which was caused by third parties and not assigned to PSI, and one incident related to the EPFL research reactor in Lausanne. The ZWILAG central interim storage facility and the research reactor at the University of Basel did not report any incidents. ENSI assigned 31 incidents to level 0 on the international INES event scale, and two to level 1. The two INES-1 incidents concerned the Leibstadt nuclear power plant. At the beginning of the main annual inspection in the containment, the local dose rate increased due to the insufficient water coverage of the removed water separator. The limited availability of the systems for heat dissipation also led to an INES-1 assessment.

Operating year 2019

There were 34 reportable incidents in the nuclear facilities in 2019: two incidents related to Unit 1, five incidents to Unit 2 and two incidents to both units of the Beznau NPP. Two incidents concerned the Mühleberg NPP, eight the Gösgen NPP and eleven the Leibstadt NPP. Pressure transmitters at the Gösgen nuclear power plant that were not tested for their suitability under accident conditions led to an INES-1 rating on the IAEA's international event scale. The remaining incidents were classified as INES 0. At Zwilag, ENSI recorded a reportable incident in the reporting year. There were three reportable incidents in the PSI's core facilities in 2019. Two of these incidents concerned the EPFL research reactor.

Criticism of ENSI

In 2012 and 2013, the ENSI Council hired the PR agency Hirzel.Neef.Schmid.Konsulenten for 50,000 francs to improve its image. The consultants stated on the reputation: “ENSI threatens to be perceived as an organization that only manages the end and is dying out like a dinosaur.” ENSI ended the collaboration because it “did not bring the expected benefits”. Documents prepared in this context were published by ENSI on the basis of a request based on the Public Information Act.

Web links

Homepage
ENSI, Zone plan for emergency protection of nuclear facilities: Danger zones for ionizing radiation Switzerland in the event of a serious accident ( INES scale 5) on the federal geoportal

Individual evidence

↑ Federal Nuclear Safety Inspectorate: ENSI's independence is secured several times , March 26, 2015

↑ Federal Nuclear Safety Inspectorate: ENSI Council

↑ Federal Act on the Federal Nuclear Safety Inspectorate

↑ Swiss Nuclear Energy Act

↑ Swiss Radiation Protection Act

↑ Nuclear Energy Act Art. 22: General duties of the license holder

↑ Collection of the guidelines in force on the website of the Federal Nuclear Safety Inspectorate ENSI

↑ Nuclear Energy Act

↑ "A lot of work for ENSI, too, with the annual NPP overhauls"

↑ Swiss Radiation Protection Act

↑ Real-time data from the MADUK measuring probe system

↑ Dispersion models from the Federal Nuclear Safety Inspectorate ENSI

↑ Collection of reportable incidents in Swiss nuclear power plants

↑ Guideline ENSI-B03 ( Memento of the original dated September 13, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. of the Federal Nuclear Safety Inspectorate ENSI on the reporting of incidents in Swiss nuclear facilities @1@ 2