Must all services, feeders, or branch circuits supplying a building be identified by a permanent plaque?

In accordance with the National Electrical Code (NEC), it is essential for all services, feeders, or branch circuits supplying a building to be identified by a permanent plaque. This requirement is designed to enhance safety and facilitate maintenance by ensuring that anyone working on the electrical system can easily identify the circuits servicing the structure. Proper identification helps prevent accidents, such as unintentional disconnection of crucial circuits and allows for correct troubleshooting during electrical work.

Having a permanent plaque also serves to inform emergency personnel about the electrical service layout in case of emergencies. These identifiers must be legible and durable to withstand the test of time and environmental conditions. This requirement applies universally and is not limited to specific building types or configurations, such as those with multiple services or only in commercial buildings. Therefore, a permanent plaque is a fundamental safety practice that applies to all buildings needing those services.