This paper presents the phenomena of irradiation assisted stress corrosion cracking (IASCC) and it describes a facility dedicated to face these issues and planned to be implemented in the Jules Horowitz material testing reactor (MTR). The structural and functional integrity of the internal components of the core of light water reactor (LWR) are major concerns. Several degradations of core components have occurred in boiling water reactors (BWRs) first and then in pressurized water reactors (PWRs). IASCC was identified as the cause of these degradations. It is today an important issue for internals materials where stainless steels and nickel base alloys have shown some susceptibility. For future reactors where the flux of high energy neutrons will be stronger or where a higher burn up is aimed, IASCC would be a major concern. The first aim of the paper is to summarize the industrial issues of IASCC for PWRs and BWRs. In these LWRs, stainless steels and nickel base alloys have exhibited IASCC. Mechanisms of IASCC are then discussed together with the effects of irradiation on metallic alloys and on water chemistry (radiolysis). In the final part, a water loop dedicated to IASCC studies is proposed to be implemented in the new MTR called Jules Horowitz reactor (JHR) with the objective of improving the understanding of IASCC and the resistance of stainless steels and nickel base alloys to this phenomena. Main characteristics of JHR and of the corrosion loop, called CLOE, are then described (190 bar max, 360°C max, PWR or BWR water chemistry conditions…). In the core, the samples will be subjected to high fast neutron flux while in the beryllium reflector, the samples are exposed to high thermal neutron flux. The use of a water loop is also planned to reproduce phenomena linked to IASCC under BWR and PWR simulated conditions. The CLOE loop is aimed to perform integral experiments with applied stresses on samples under neutron flux so that IASCC studies could be performed.