The Trino Vercellese Nuclear Power Plant operated by Ente Nazionale per l'Engergia Elettrica included a reactor vessel material radiation surveillance program which served as a model for ASTM Recommended Practice for Surveillance Tests for Nuclear Reactor Vessels (E 185-73). Early in the life of the plant the original reactor vessel material surveillance program had to be discontinued; thus, a second surveillance program was implemented. Postirradiation data generated from two of the surveillance capsules indicated that the reactor vessel material was relatively insensitive to irradiation.
To supplement this reactor vessel surveillance program, an accelerated irradiation program was initiated in a test reactor in the United States of America. The current surveillance program and the accelerated irradiation program included fracture mechanics specimens as well as Charpy V-notch impact specimens.