A control rod for a nuclear plant

摘要

The present invention relates to a control rod for a nuclear plant. The control rod (1) is arranged to be provided in a fuel assembly of the nuclear plant and to be in contact with cooling water. The control rod (1) comprises at least an inner space (3) which is adapted to receive an absorber material (4) for allowing absorption of neutrons during operation of the nuclear plant. The absorber material (4) allows formation of at least one gaseous substance during said absorption process. The control rod comprises at least a filter member (7) having a material structure which allows passage of the gaseous substance out from the space (3) at the same time as the material structure prevents a passage of surrounding cooling water into the space (3).