The U.S. Nuclear Regulatory Commission (NRC) is issuing a new Regulatory Guide (RG) 3.78 (Revision 0), "Acceptable ASME Section XI Inservice Inspection Code Cases." This new RG provides applicants and licensees with methods that the NRC staff considers acceptable for specific or general independent spent fuel storage installation (ISFSI) licensees and certificate of compliance (CoC) holders to comply with NRC regulations for inservice inspection of confinement boundary components and aging management activities associated with the renewals of ISFSIs, general licensees, and CoC holders for spent fuel storage systems.