I&C Equipment Qualification In Nuclear Power Plant

With the increase of greenhouse gases which are produced by human activity, the resulting environment problem as global warming is more serious. For this reason, many countries begin to develop the clean energy rapidly.The first essential step in qualification is to identify the systems and equipment important to safety. The nuclear power plants safety systems have isolation and diversity criteria. The reliability of safety important equipments is important. One aspect of defense-in-depth is a tolerance for single, randomly occurring failures provided by designed-in redundancy of safety systems. Qualification aims at eliminating "common-cause" failures that can defeat redundancy by incapacitating the two or more paths or trains available for providing essential safety function. Given the above concepts related to common-cause failures called equipment qualification. Our country always uses IEEE and RCCE standards. This paper describes, from the view point of defense in depth, the signification and key points as well as procedures and approaches to environmental qualification for class IE electric equipment in nuclear power plants. Principles presented in standards, such as IEEE323, R.G.1.89, and IEC60780, are detailed to the extent of being operable.