Does UL apply a Listing Mark to a product based on evaluation to an Outline of Investigation?


Does UL apply a Listing Mark to a product based on evaluation to an Outline of Investigation?



Yes, in cases where a published UL Standard does not cover a product submitted for investigation and certification, an Outline of Investigation may be used and contains basic requirements for such products.

When the first submittal of a new type of product is received, UL can evaluate the product for compliance with the appropriate requirements selected from related UL Standards, UL’s technical experience with the basic hazards involved using Hazard Based Safety Engineering principles, and appropriate safety requirements of other organizations. The product evaluation which results in the first Listing (or other type of certification, such as UL Classification) of the new type of product then becomes the basis for UL’s requirements for subsequent product submittals for the new product category and the requirements are documented in an Outline of Investigation.

UL’s Guide Information for the product category references the Outline of Investigation, and this document is maintained by UL in the same manner as UL Standards. UL’s Primary Designated Engineers (PDE) periodically review an Outline of Investigation for conversion to a UL Standard. Factors considered include the number of manufacturers of the product, references to the Outline of Investigation made by AHJs, and the need for ANSI recognition.

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