What does it mean when equipment, material, or services are shown as 'listed'?

What does it mean when equipment, material, or services are shown as 'listed'?

• A. They have been found tolerable for the purpose described in the manufacturer's specifications.
• B. They are identified and published by an organization that is acceptable to the authority having jurisdiction.
• C. They have been tested and approved by the construction supervisor.
• D. They have been tested by a medical gas verifier.

Answer: (B)

Listing means a product has been evaluated by a recognized testing organization and included in that organization’s published listings. This third‑party evaluation shows the item meets applicable standards and performance criteria, giving confidence to authorities and inspectors that it is suitable for its intended use, especially in regulated systems like medical gas installations. The important point is that the listing comes from a respected, independent body, not from the manufacturer or a local supervisor. Therefore, when equipment, material, or services are listed, they are identified and published by an organization acceptable to the authority having jurisdiction. This acceptance by the AHJ is what allows the item to be approved for use in code‑regulated contexts. It isn’t simply a manufacturer’s claim of tolerability, nor is it something verified solely by a construction supervisor or a specific verifier role.

Listing means a product has been evaluated by a recognized testing organization and included in that organization’s published listings. This third‑party evaluation shows the item meets applicable standards and performance criteria, giving confidence to authorities and inspectors that it is suitable for its intended use, especially in regulated systems like medical gas installations. The important point is that the listing comes from a respected, independent body, not from the manufacturer or a local supervisor.

Therefore, when equipment, material, or services are listed, they are identified and published by an organization acceptable to the authority having jurisdiction. This acceptance by the AHJ is what allows the item to be approved for use in code‑regulated contexts. It isn’t simply a manufacturer’s claim of tolerability, nor is it something verified solely by a construction supervisor or a specific verifier role.