The French Institute for Radiological Protection and Nuclear
Safety (IRSN) and the European Commission's Joint Research
Center (JCR) will be holding the fifth seminar devoted to
Phebus FP, the international nuclear research safety program,
in Aix en Provence on June 24-26, 2003.
The seminar, which presents the world's most important safety
research program concerning nuclear power plants, will draw
more than a hundred nuclear safety experts and scientists
from Japan, Canada, the United States, and countries in both
Western and Eastern Europe.
Five experiments on severe accidents
The program includes experiments to reproduce all the phenomena
involved during a core meltdown accident and contributing
to the release of radioactive products. Its aim is to provide
further insight into the complex phenomena encountered during
this type of accident. This should improve the action taken
to limit the impact of the accident by providing more accurate
assessments, and optimize the emergency plans set up around
plants. The knowledge acquired could also help to make future
nuclear power plants even safer.
Partners and resources: the international dimension of
The Phebus FP program is conducted by IRSN in association
with the European Commission JRC, EdF, and American, Canadian,
Japanese, Korean, and Swiss nuclear safety organizations.
Launched in 1993 with an initial test, it has an estimated
cost of €300 million.
An unrivaled experimental setup
The experimental setup, installed in the heart of the Phebus
reactor operated by the CEA at its Cadarache research center,
is a small-scale replica of a pressurized water reactor, the
most widely used type of nuclear power reactor in the world.
The setup has undergone considerable change since the end
of the 1980's to ensure the efficiency and safety of the Phebus
FP tests. In particular, its building was reinforced before
the program started to withstand the severest earthquakes
liable to occur on the site (intensity IX on the MSK scale,
which comprises twelve levels of intensity).
Performing an experiment
Each experiment is prepared with meticulous care, making
extensive use of predictive calculations obtained using a
variety of software programs. In this way, the experimental
protocol can be established and the criteria for ending the
experiment defined. This preparatory phase lasts about four
Specific objectives for each test
So far, four tests have been successfully completed and
the next (and last) test is planned for 2004. The first experiments
yielded original results on core meltdown mechanisms and iodine
volatility. They were used in more recent evaluations of the
radioactive releases to be considered in the preparation of
Furthermore, the OECD has chosen the second experiment in
the program as a reference for a standard international exercise
involving 30 organizations from 20 countries aimed at testing
the performance of various severe accident simulation codes.
Audrey Lebeau / Press Office - 33 (0)1 58 35
Gilles Bertin-Maghit - 33 (0)4 42 25 32 53