This standard considers the functional design criteria for a Safety Parameter Display System (SPDS) which provides information in a concise manner to aid reactor personnel, particularly under abnormal conditions. Computer based systems are used to display the main parameters associated with critical safety functions of light water reactors such as: reactivity control, reactor coolant system integrity, reactor core cooling and heat removal from primary system, radioactivity control and containment integrity. This standard provides functional design criteria only and is only applicable to plant control rooms that were not designed in accordance with the IEC control room design standard. The SPDS consists of instruments, displays, hardware and computer software forming a standalone system or integrated into the control room information system.