6. Conclusion

This safety review of the various Generation IV reactor concepts shows that their maturity and available experience feedback are highly heterogeneous; it also demonstrates the need, for each of them and despite the intrinsic advantages they may present, for significant technological advances. What's more, a concept such as the MSR would require a specific review and adaptation of the safety approaches used for Generation II and III power reactors.

It is also clear that, generally speaking, the specific features and risks highlighted in this article relate to a few well-defined areas:

• intrinsic core characteristics (neutronics) and criticality risks ;

• compatibility between the heat transfer fluid and structural materials (corrosion risks, etc.), as well as in-service inspection options;...