UID labeling involves many steps: From design to IUID verification

Department of Defense contractors have many details to think about when determining how to comply with the department’s Item Unique Identification (IUID) requirements. The IUID program involves the marking of individual pieces of equipment with a Unique Identification (UID) that stays with the item throughout its life. The marking is accomplished using a 2D Data Matrix symbol that is read with an automated scanner.

Decisions to be made include how the UID labels will be applied to the item; where the labels will be located; and the size of the mark. Finally, IUID verification is needed to ensure the symbol is of high quality and will be readily readable and in the proper syntax.

According to DoD standards, the Data Matrix symbol should remain readable throughout the life of the item; withstand environmental conditions the item may encounter; and not harm the performance, durability or reliability of the item.

The latter concern may come up when one is deciding which labeling method to use. There are two methods of applying UID labels: Direct and indirect marking. Direct marking methods include dot peening, laser marking, electrochemical etching, and engraving. While these marks are durable, care must be taken that the marking process does not damage the equipment or affect its performance. In some cases, metallurgical testing may be required before the marking method is approved. 

Indirect labeling methods involve applying the Data Matrix symbol to a tag — made of a durable material — which is then securely attached to the item to be labeled. This method is often less expensive than direct labeling. The method of attachment also needs to be evaluated to be sure the label will remain on the item throughout its life. Light, heat and corrosion can weaken the attachment over time.

Where to place the UID labels is another issue to address. Ideally, the label will be readable both when the item is in use and when it is in storage. Applying the label to a flat, rather than curved, surface is preferable. If possible, avoid placing the label over an air vent or sensor, near a heat source, or on a component that may be replaced during maintenance.

A crucial step in the UID process is IUID verification. Hardware and software are used to evaluate the UID labels on several parameters related to its readability and overall syntax. It may be wise to consult with UID labeling experts such as ID Integration, Inc. (www.id-integration.com).