Factory-floor workers are likely to have difficulty differentiating between product labels that contain radio-frequency identification transponders and those that don't, according to market researcher ARC Advisory Group. But a new specification could help. The AIM RFID Mark spec provides a way for companies to visually identify RFID-enabled bar-code labels. The specification is designed to be built into labels and can help workers using handheld readers sort out the different label types. The marker will serve as a visual identifier that differentiates RFID labels. Developed by the AIM North America Standards Action Group, the mark is a distinctive pattern containing a two-character code that defines the type of transponder and data.