Why should electricians be concerned whether equipment they’re installing is labeled or listed? As an electrician in San Francisco my work is frequently inspected by San Francisco electrical inspectors and my goal is to pass those inspections on the first try. Competent and professional electricians give their customers safe electrical installations in compliance with the NEC. Check out NEC 110.3(B). This is why electricians need to be concerned about equipment being labeled and listed.
There are organizations, accepted by AHJ’s, dedicated to ensuring that items (equipment or materials) are made to a standard. Periodic inspections by these organizations of the item’s production are required to ensure the product meets the standard and continues to meet the standard. Standards specify certain physical and operational characteristics. These organizations attach a label that indicates compliance. If the equipment or material has this label attached it is considered labeled.
What it means to be listed is very similar. Instead of the equipment or material having a label attached indicating compliance with standards, the equipment or material is included on a list to indicate compliance with a standard or suitable for a specific purpose.
Recently, I purchased a handheld video game console from a social media platform. While charging the device, the wire melted and began smoking. Shoddy products are frequently sold to unsuspecting consumers. The labeled and listed system helps consumers know the equipment or material is safe to attach to your home’s electrical system.
I have had San Francisco electrical inspectors inquire if the device I’ve installed is labeled or listed. Luckily, so far this has never been the reason I’ve failed an inspection, but I have heard rumors that some SF electrical inspectors have failed inspections for equipment not being labeled or listed.
Labeled and Listed are terms defined in Article 100 of the NEC.
Stay Safe, Buddy