How should circuit conductors be labeled?

• A. With clear identifiers, color codes, and circuit numbers on accessible labels or tags.
• B. By painting the wires with the same color as insulation.
• C. By stamping the main panel with numbers only.
• D. By labeling only at the end of the circuit.

Answer: (A)

Clear labeling of circuit conductors should include distinct identifiers, color codes, and circuit numbers on labels or tags that are easily accessible. This helps anyone working on the system quickly identify which wire is which, which circuit it belongs to, and where it runs from the panel to its loads. Use durable, weather-resistant labels placed at points where conductors are exposed or terminated—such as the panel, junction boxes, and near terminations along the route. Color codes support quick recognition of basic function (hot, neutral, ground) and should be used in combination with unique circuit numbers so that different circuits aren’t confused by color alone.

Painting wires the same color as insulation isn’t a reliable labeling method because it doesn’t provide unique, traceable identification and can wear off or be misinterpreted. Stamping the main panel with numbers identifies the panel, not the individual conductors. Labeling only at the end of a circuit fails to show how the conductor runs or what it controls, making troubleshooting and safety checks harder.