What does it mean when equipment is described as "Listed"?

When equipment is described as "Listed," it indicates that this equipment has been evaluated and included in an approved organization's published list of products that meet specific safety and performance standards. This listing typically confirms that the equipment has undergone rigorous testing and complies with relevant safety codes and regulations, providing assurance to consumers, installers, and inspectors of its reliability and safety.

The concept of "Listing" is integral to the National Fuel Gas Code as it helps ensure that the products used in gas systems have been vetted for quality and safety. Therefore, when you see that a piece of equipment is "Listed," it assures you that it has been reviewed by a recognized third-party testing organization, which serves as a valuable credential in the industry to ensure compliance with construction and safety standards.