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  2. Item Unique Identification (IUID)

Item Unique Identification (IUID)

ALCL 061


Alternate Definition

A system of marking items delivered to DoD with unique item identifiers that have machine-readable data elements to distinguish an item for all other like and unlike items. For items that are serialized within the enterprise identifier, the unique item identifier shall include the data elements of the enterprise identifier and a unique serial number. For items that are serialized within the part, lot, or batch number within the enterprise identifier, the unique item identifier shall include the data elements of the enterprise identifier, the original part, lot, or batch number, and the serial number. "Enterprise” means the entity (e.g., a manufacturer or vendor) responsible for assigning unique item identifiers to items. “Enterprise identifier” means a unique code that is assigned to an enterprise by an issuing agency.

Alternate Definition Source

DFARS 252.211-7003 Item Unique Identification and Valuation  

General Information

Item Unique Identification (IUID) is one of a family of automatic identification technologies (AIT). IUID transfers its identifiers via both human readable text and machine scannable codes. Two other (of many) forms of AIT are common access card (CAC) and radio frequency identification (RFID). Each Federal employee, whether military or civilian, carries a CAC as unique identification. CAC transfers its identifiers via photograph, barcode, and embedded smart chip. RFID uniquely identifies shipping containers and other transportable loads. RFID transmits its identifiers using a passive chip passing through an inductive loop located at warehouse doors. Note that a shipping container with several serialized radios inside could have an RFID chip on the outside of the container while each of the radios may have separate IUID marks.

DoD requires IUID for all new item acquisitions meeting one or more of these criteria:

  • Line item acquisition cost in its contract of $5,000 or more
  • Serially managed by the DoD
  • Controlled or mission essential
  • Government wants permanent identification for any other reason

Some manufacturers mark nearly all parts regardless of the above criteria because they use IUID internally for pedigree (parent/children) tracking and error proofing of manufacturing and factory maintenance. The IUID Registry (described below) readily accepts the records of these additionally marked parts.

Serially-managed legacy items may also be IUID relevant according to the decision tree in DoD Instruction (DoDI) 8320.04, Item Unique Identification Standards for Tangible Personal Property. Legacy means that the item is already in the government’s inventory.

For embedded items, the only criteria for IUID are whether the item is or will be DoD serially managed or if the government wants permanent identification for any reason. Embedded items are parts or components delivered under contract without their own line item specifying their explicit cost.

For new acquisitions, the government includes DFARS clause 252.211-7003, Item Unique Identification and Valuation, in the contract. As part of this clause, DoD identifies items that need or don’t need IUID as exceptions to the criteria and categories described above.

The issuing agency (government or contractor) assigns a globally unique, permanent Unique Item Identifier (UII) as an early step to affixing an IUID. Most likely, the UII becomes part of the IUID Registry when the government accepts the corresponding item in Wide Area Workflow (WAWF). Generally, this acceptance is part of the Material Inspection and Receiving Report (DD Form 250) process.

The IUID Registry is the central repository for IUID information and serves as an acquisition gateway to identify:

  • What the item is
  • How and when it was acquired
  • The initial value of the item
  • Current custodial agency (government or contractor)
  • How it is marked

The IUID Registry is also the master data source for Government Furnished Property (GFP) in accordance with DoDI 8320.04. GFP items in the IUID Registry may or may not be uniquely identified.

The issuing agency encodes the UII data into an ECC200 data (two-dimensional) matrix . Then, it applies the mark using a method based on its assessment of the technical characteristics and usage environment of the item. Marking methods include adhesive foil labels, laser marking, shot peening, thermal spray, et al. The IUID mark is scalable per the dimensions of the marked parts from pinhead size to 11 inches square. Each IUID mark contains multiple copies of the same few fields (3-4, depending on chosen construct) of encoded data. This redundancy allows damage to 40 percent of the mark without affecting its readability.

As previously mentioned, each IUID is globally unique and permanent for the life of that item (and forever beyond). Even with major modification, depot rebuilding, consumption in use, or disposal, a specific UII pertains to only the first item marked. If the IUID mark remains readable, continue to use it as-is. When the mark becomes unreadable, the current custodian of the item applies a new IUID mark using the previously assigned UII (not a new UII).

If an item already contains another globally unique identification, it does not need to have an IUID in addition to the other acceptable identifier. The DoD recognizes six other schemas as IUID equivalents:

  1. Vehicle identification number (VIN)
  2. Cellular mobile telephone identifier (CMTI)
  3. Mobile equipment identifier (MEID)
  4. Electronic serial number (ESN)
  5. Global individual asset identifier (GIAI)
  6. Global returnable asset identifier (GRAI).

For additional information, see also: