How are listed and labeled electrical products defined?

• A. Listed products have been tested and comply with applicable standards by a recognized testing laboratory and are labeled accordingly
• B. They are simply labeled by the manufacturer
• C. They are any products installed in the field
• D. They have no testing

Answer: (A)

Listing means the product has been tested by a nationally recognized testing laboratory to applicable safety standards and approved for use. Labeling means the product carries a mark from that lab (and often the manufacturer’s information) showing it complies with those standards and its electrical ratings. In residential work, you rely on that listing to confirm a device is safe and appropriate for its intended installation.

That’s why the best description is the one that states it has been tested by a recognized testing laboratory and complies with standards, and is labeled accordingly. Simply being labeled by the manufacturer isn’t enough, and products installed in the field or without testing aren’t considered listed or labeled.