Which color indicates 110V?

• A. Yellow
• B. Blue
• C. Red
• D. Green

Answer: (A)

Color-coding is used to quickly identify the voltage level of a circuit to keep workers safe. In this material, yellow is the color used to indicate a 110V circuit. Seeing yellow tells you that the conductor or outlet is a lower-voltage setup, which helps distinguish it from higher-voltage circuits and reduces the risk of shock or incorrect connections.

Other colors have different roles in common practice: blue is often associated with other phases or a different function, red typically marks another hot or higher voltage circuit, and green indicates grounding. Keep in mind that color schemes can vary by region and code, so always verify with the local standards.