The Unique Device Identification (UDI) is a system used to mark and identify medical devices produced and distributed within the healthcare sector.

The system utilizes UDI labels to clearly identify medical devices for all parties in the supply chain.


The Food and Drug Administration (FDA) goal is to ensure public safety and transparency between food and medical suppliers and their consumers.

In an effort to better serve this goal, the FDA established the Unique Device Identification (UDI) system to improve the level of identification for medical devices.

The UDI system follows the device from manufacture to end use. A designated device labeler must clearly mark the UDI number assigned to a device on labeling and packaging. The labeler is typically the manufacturer of the device.

A unique number is assigned to each version of a device. This should be labeled in human readable (HRI) as well as AIDC formats.

UDI codes themselves are issued by FDA-accredited agencies:

  • GS1
  • Health Industry Business Communications Council (HIBCC)

All items under the medical devices category available for use in the US are required to comply with the system. This includes many single-use items as well.


Many nations across the globe have adopted the UDI standard. In an attempt to create a globalized standard for the labeling of medical equipment and devices, a Global Unique Device Identification Database (GUDID) was established.

Device information must be submitted to this database to prevent any numbers accidentally being duplicated. Duplicated codes would essentially defeat the purpose of the system.

Compliance Dates

The initial program was set forth in September of 2013. Since compliance deadlines have extended several years in order to allow the industry time to adopt the new requirements.

The majority of medical device class distinctions were incorporated in 2016 and 2018, with Class I devices being added by September 2020.

What Information Goes on the Label?

UDI is a unique code that consists of a Device Identifier (DI) and Production Identifier (PI). Each element contains specialized criteria.

The Device Identifier is the more standardized element, as it simply identifies the device labeler, as well as specifies a version or model of the item.

Production Identifiers are conditional and may require different information for each UDI code.

These can include:

  • Date of Manufacture
  • Item Expiration Date
  • Batch Number
  • Serial Number
  • Specific Codes for Other Regulations

This information must be provided in both human-readable plain text, as well as an AIDC format (i.e. a barcode or QR code).

Marking Processes


The primary method for identifying medical devices is with UDI labels. These labels typically feature a digitally printed design on a vinyl or polyester material.

Digital printing means that the label can include any type of custom design. Logos, various colors, and barcodes can all be added to the design.

Safety Tags Decals Label Full Color

Keep in mind that this is a topical ink. Surface-level printing can be vibrant but is susceptible to wear and tear. The ink will eventually fade and wear after being exposed to use.

In addition, UDI labels are produced with a highly strong adhesive backing. This allows for simple and easy attachment to tools, instruments, and other devices.

Photo Anodization

While the main substrate used for medical devices is typically vinyl or polyester, some applications call for metal materials as well.

This may be due to the necessity for a more long-lasting situation, such as marking a machine that will see prolonged use, instead of a single-use disposable medical instrument.

The photo anodization process embeds a design beneath aluminum layers. This custom marking can include any information or design. This includes barcodes, data matrix codes, and QR codes to meet the AIDC compliance.

Similarly to digitally printed labels, photo anodized tags can be attached via adhesive backing, or directly bolted onto equipment.

Direct Marking

In some instances, adding an additional tag or label to a device is counterproductive, or cannot be performed due to the nature of a specific medical instrument.

In these cases, direct part marking (DPM) is often a better alternative. The processes for direct marking can include stamping, engraving, or dot peen marking.

Direct marking is also considered a permanent solution, as the mark cannot be simply peeled off like an adhesive label could. The information is physically marked into the surface of the device or machine.

This method is sometimes preferred due to the ability to mark information into a very small surface area. This can include barcode symbols as well such as data matrix and QR Codes.

Additionally, if a device is going to be reused and reprocessed after use, the UDI must be marked directly on the device.

Marking a QR Code directly on a device allows for a large amount of information to be stored directly where it needs accessed.


The UDI system serves an important purpose in the healthcare supply chain. Ensuring full transparency and identification of medical devices provides a safer environment for both patients and practitioners.