National Electrical Code (NEC) Requirements for Surge Protective Devices

In the United States, The National Electrical Code® (NEC®) sets forth installation requirements for electrical systems and equipment, including Surge Protective Devices (SPDs). The NEC provides guidance regarding where SPDs should and should not be used and how they may be installed in electrical power distribution systems.

Triennial revisions to the NEC make it important to track the editions of the code that is in effect for a project location. The NEC articles referenced herein constitute the bulk of requirements regarding the location and use of SPD in power distribution system. A look-up table summarizing key SPD-related NEC requirements is provided as follows.

Key 2017 NEC Surge Protection Provisions
Article Application Requirements
285 Surge Protective Devices 285.4, 285.6, 285.12, 285.3, 285.7
517 Healthcare Facilities 517.2, 517.26
620 Elevators/Escalators 620.51
645 IT/Data Systems 645.18
670 Industrial Machinery 670.6
695 Fire Pumps  695.15
700 Emergency Systems 700.1, 700.8
708 Critical Operations Power Systems 708.2, 708.10(D), 708.14(4)