Branch Circuits & Receptacles

When more than one nominal voltage system is present in a building containing multi-wire branch circuits, each ungrounded conductor of a multi-wire branch circuit, where accessible, must be identified by phase and system. The means of identification must be permanently posted at each branch-circuit panelboard.

Receptacles installed on 15- and 20-ampere branch circuits must be of the grounding type except as permitted for replacement receptacles. Grounding-type receptacles typically must be installed only on circuits of the voltage class and current for which they are rated.

The grounding contacts of receptacles and cord connectors must be grounded by connection to the equipment grounding conductor of the supplying circuit. The branch circuit wiring method must provide an equipment grounding conductor. The grounding contacts of the receptacle or cord connector must be connected to this.

Where a grounding means exists in the receptacle enclosure or where a grounding conductor is installed, grounding-type receptacles must be used and be connected to the grounding means or conductor. Ground fault circuit interrupter (GFCI) protected receptacles must be provided where replacements are made at receptacle outlets where protection is required.

When a grounding means does not exist in the receptacle enclosure, a non-grounding-type receptacle may be replaced with certain other receptacles detailed in 29 CFR 1910.304.

All 125-volt, single-phase, 15- and 20-ampere receptacles installed in bathrooms or on rooftops must have GFCI protection.

In temporary wiring installations that are used during construction and maintenance activities, all 125-volt, single-phase, 15-, 20-, and 30-ampere receptacle outlets in use by personnel that are not part of the permanent wiring of the structure and must have GFCI protection for personnel.

Receptacles other than 125 volt, single-phase, 15-, 20-, and 30-ampere receptacles that are not part of the permanent wiring of the structure and that are in use by personnel must have GFCI protection. Where the required GFCI protection is not available for such receptacles, the employer must establish and implement an equipment grounding conductor program covering cord sets, receptacles that are not a part of the building or structure, and equipment connected by cord and plug that are available for use or used by employees on those receptacles. The employer must designate one or more competent persons to implement the program.

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