Can a manufacturer add labels to a UL Listed product in the field, even if the label is not a Listing Mark?
No, when you add labels to a Listed product after it leaves the factory, it is considered a Field Modification. The product was never reviewed to determine if the attribute identified on the added label or marking is accurate or continues to comply with UL’s requirements. In order for UL to determine if that product still complies with UL’s requirements, UL would have to conduct a Field Inspection or Field Evaluation to determine if the modifications are still in compliance with the UL’s requirements. Some examples would be changing the electrical rating nameplate or applying a label in the field to distribution equipment stating that the product is Suitable for Use as Service Equipment (also known as a SUSE label). If you encounter a situation where labels are added to a Listed product in the field, it would be warranted to require a UL Field Inspection or Field Evaluation as part of your approval decision.
UL’s Field Modification policy states:
An authorized use of the UL Mark is the manufacturer’s declaration that the product was originally manufactured in accordance with the applicable requirements when it was shipped from the factory. When a UL-Listed product is modified after it leaves the factory, UL has no way to determine if the product continues to comply with the safety requirements used to certify the product without investigating the modified product. UL can neither indicate that such modifications “void” the UL Mark, nor that the product continues to meet UL’s safety requirements, unless the field modifications have been specifically investigated by UL. It is the responsibility of the Authority Having Jurisdiction (AHJ) to determine the acceptability of the modification or if the modifications are significant enough to require one of UL’s Field Engineering Services staff members to evaluate the modified product. UL can assist the AHJ in making this determination.
An exception for a field modification authorized by UL is when the product has specific replacement markings. For example, a switchboard may have specific grounding kits added in the field. The switchboard is marked with a list of specific kit numbers that have been investigated for use in that particular switchboard. Only grounding kits that are included on the marking on the product have been investigated for use in that product.
If a party wishes UL to determine if the modifications made to a UL Listed product comply with UL requirements, the appropriate Field Engineering Service can be initiated to investigate the modifications. This investigation will only be conducted after UL consults with the AHJ to ensure that UL’s investigation addresses all areas of concern and meets all of the AHJ’s needs.
If you have any questions or would like to inquire about a Field Evaluation, contact Field Services at +1-877-UL-HELPS, prompt #2 (+1-877-854-3577) or visit http://www.ul.com/field.
For more information on UL’s Field Modification Policy see page 41 in the 2011 UL White Book or online at www.ul.com/codeauthorities and click on the “Concerns with products in the field” link.