Listed
Equipment, materials, or services that have been evaluated by a nationally recognized testing laboratory (NRTL) and found to meet appropriate safety standards.
Detailed Explanation
NEC 110.2 requires that only listed equipment be used in electrical installations. Common listing organizations include Underwriters Laboratories (UL), Intertek (ETL), and CSA Group. A listing mark (like the UL logo) on equipment means it has been tested to applicable standards (such as UL 489 for circuit breakers). Using unlisted equipment can result in inspection failure, insurance issues, and potential safety hazards.
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Which of the following best describes the concept of Listed?