This recommended practice addresses activities related to PPS reliability, including design considerations, analytical studies, operational and maintenance considerations, and IAs between an NPGS and its associated Transmission Entities. This document provides a recommended practice to enhance the PPS reliability with respect to NPGS requirements. New IEEE Standard - Superseded. This recommended practice addresses activities related to preferred power supply (PPS) reliability, including design considerations, analytical studies, operational and maintenance considerations, and interface agreements between a nuclear power generating station (NPGS) and its associated Transmission Entities.