Regional Basic Professional Training Course in Korea

Regional Basic Professional Training Course (BPTC) on Nuclear Safety
Neutron beam channels in research reactors such as RHF, may lead to the risk of core
dewatering and irradiation of physicists and operating staff who may be working on
devices using neutron beams. To avoid the risk of core dewatering, the neutron channels
are fitted with isolation valves that close automatically if they detect water in a channel.
Furthermore, the operators of research reactors need to come to agreements with the
physicists over establishing the precise role and responsibility of each party and over
improving the conditions of radiological monitoring and protection in experiment areas.
Total loss of power supplies to pool‐type reactors causes the safety rods to drop
automatically and does not affect the removal of the decay heat of the core. This is
removed by natural convection by means of flappers with counterweights that do not
require human intervention or electrical power to open. The short‐term loss of the
negative pressure differential in the containment does not have consequences for the
environment unless it is accompanied by contamination inside the containment.
4.2.4.2. Safety criteria
The general safety principles that apply to research reactors have been established over
time. For example, the redundancy and separation of the safety systems, the continuous
monitoring of the containment barriers in relation to the underlying soil and the water
table.
Modifications were steadily made to the different installations in France in order to
observe these principles and to improve protection against fire risks.
As far as risks relating to earthquakes, the industrial environment and communication
networks are concerned, the rules adopted for the design of French research reactors are
the same as those applicable to power reactors, with certain adaptations in view of the
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