UL variation notice and corrective action requirements:  UL/C-UL/ULC Mark Follow-Up Services

UL defines minimum requirements for actions by manufacturers in response to UL variation notices for nonconformances to UL requirements.

When a product does not comply with the follow-up service procedure, applicable standard or other UL requirements, UL representatives document the nonconformance on a variation notice (VN). A variation notice is a channel of communication between UL and a manufacturer and creates a record when nonconformances are discovered.

View the Variation Notice Corrective Action requirements document.