This standard provides the basic principles for qualification of equipment used in nuclear facilities; it does not define the scope of equipment requiring qualification nor does it provide guidance on how to classify equipment. Other standards that present qualification methods for specific classifications of equipment@ specific types of equipment@ specific environments@ or specific aspects of a qualification program may be used to supplement this standard@ as applicable. The bibliography contains a partial list of references@ including other standards@ related to equipment qualification. Purpose The purpose of this standard is to provide basic principles and guidance to demonstrate the qualification of equipment. Qualification is intended to confirm the adequacy of the equipment design to perform its required function or functions over the expected range of operational conditions@ which could include any combination of normal@ abnormal@ design basis event@ design extension condition@ or in-service test conditions for which the equipment has a required function. The level of qualification depends on the nature of the required function; a required safety function necessitates a higher level of qualification than a function that is not classified as safety-related. See IEEE Std 603TM for additional guidance on the classification of electrical equipment. For those facilities adopting a risk-informed categorization program@ see IEEE 1819TM [B26] for additional guidance on the risk-informed classification of electrical and electronic equipment.