Prescriptive Versus Performance Rules

摘要

THE NATIONAL ELECTRICAL CODE (NEC) is primarily a prescriptive-based code, meaning it indicates requirements and not what must happen electrically. Performance rules, on the other hand, clarify what must be accomplished electrically. For example, a prescriptive requirement in the Code could convey that a certain type of protection is required, such as Section 210.8(B), which mandates ground-fault circuit-interrupter protection for 125-volt (V), 15- and 20-ampere (A) receptacles in locations or facilities other than dwelling units. In Article 100, the informational note to the definition of "ground-fault circuit-interrupter" provides performance language that indicates the level of milliamperes at which the protection must operate.