UL Certification Standard System
 

UL certification standards, which involve almost all kinds of products, are the basis of product identification. UL publishes more than 500 standards, 70 percent of which are adopted as U.S. national standards by the American National Standards Institute (ANSI).

 

1, UL certification standard structure

 

In general, the structure of UL certification standards can be broadly divided into:

 

(1) The range of products covered by the standard;

 

(2) product structure requirements;

 

(3) Requirements for raw materials used in the product;

 

(4) Requirements for components used in the product;

 

(5) UL laboratory's requirements and test methods for sample testing instruments;

 

(6) Test equipment requirements and test methods for the manufacturer's factory;

 

(7) Product labeling and specification requirements.

 

2, UL certification standard revision

 

The UL standard is an ever-evolving document. Revisions to UL certification standards are requested by industry, users, UL engineers, or other interested parties.

 

Industry Modification procedures: When certain content of the UL certification standard needs to be modified, the requirements for a product will change accordingly. Therefore, UL has established a formal industry modification procedure.

 

The expiration date of each UL certification standard change is published. Products that are part of UL's tracking and inspection services must be changed in accordance with the new requirements from the effective date, so there is ample time between the date the standard is revised and the published effective date for the factory to change its own products and submit them to UL again for testing.

 

After the formal adoption of the change request, the industry revision process is carried out. This process includes sending formal notice to the applicant, the start date of the change, and having UL engineers assist the applicant in inspecting the part of the product that needs to be changed in the same way as they used to authenticate the product, as well as revising the UL factory tracking inspection documents prior to the effective date.

 

After the new UL certification standard becomes effective, a UL inspection representative will visit the manufacturer to review the changes in accordance with the revised requirements.