Make your mark – the challenge of unique device identification

On 24 September 2013, the US FDA released its final ruling on the introduction of unique device identification (UDI) within the medical device sector. The ruling is intended to give full traceability of medical devices within the supply chain from the point of manufacture through to point of use on the patient. One of the requirements for manufacturers is to ensure that all of their devices are clearly marked with a unique identifier at each packaging level.

UDI is in two parts: the device identifier, a unique number allocated to a product at a packaging level, and the production identifier, which is the quality control system used by the manufacturer (for example, lot number, expiry or manufacturing date and/or serial number). The UDI should be shown on the product labelling at each packaging level, and for reusable devices marked on the actual product. It should be shown in both machine and human-readable formats.

Within Europe, UDI will be a requirement of the new Medical Device Directive, so it is imperative that all manufacturers of medical devices are aware of the ruling, and if they have not already started to implement UDI on their product labelling then they should treat it as a priority in the coming months.

Systems and processes

Manufacturers will need to look at their printing systems and manufacturing processes, and assess whether any changes or upgrades to the current technologies are needed in order to meet these new requirements. There are a number of different options that could be chosen, depending on a number of factors ranging from the product type through to the way the actual production lines run. Printing systems for labelling and packaging can range from highly technical, high-speed online printing to more basic offline printing with manual label application.

For example, labels could be created individually in a simple software package and printed on an offline printer. The labels would then be applied manually at the relevant packaging level. This system would be used where the packaging process is very manual, and although it involves minimum cost to set up, the labour costs would need to be considered.

The next step up would be to print the labels offline and use label applicators on the packaging line. It's a relatively popular solution and is ideal for automated packaging lines. Again, the implementation costs are fairly low, with a lesser amount going into additional labour.

With both of the above examples, any printing issues could obviously be resolved offline prior to the production run and therefore would not result in any delays to the production process.

The most expensive option would be full online printing, with information obtained directly from the material requirements planning (MRP) system and applied to the packaging. This option is ideal for fully automated, high-speed production lines, removing any requirement for additional steps to the process and therefore minimising manual labour input. However, there may be an effect on the speed of the packaging line. Also, if there are any printing issues, it could lead to downtime while the problems are corrected.

A second part of barcode production is verification of the symbols being printed - the process of actually checking the printed barcodes to ensure they are readable and of a good quality, and contain the correct information. This, too, can be completed as either part of an automated process or a more manual system.

Verification can be done in a number of ways. Standards organisations such as GS1 offer a verification service to their members. You can send samples of printed barcodes to them and they will verify the codes for you, giving feedback on the quality and suggesting improvements if required.

However, this method is probably not very practical for ongoing verification. Depending on the size of the organisation, the best methods would be to purchase the verification equipment and verify in-house, which can be carried out either offline during the label printing process or as an integral part of the production and labelling process, with online verifiers checking each label (although it's possible to just check random codes at preset intervals within production).

For offline verification you can either verify every label that is printed with a machine attached to the printer, which will let you know if a label is out of specification, or have stand-alone verification and test a sample number of labels (e.g. at the beginning, middle and end of a print run).

Once it can be confirmed that the quality of the codes being produced is consistent, spot checks at various points of production will enable you to reduce the amount of tests you need to complete.

Assessment

Before deciding on the type of system required within a business, it is crucial to ask the following:

1. Are barcodes already applied to labelling?
2. Does the content of the barcodes meet the requirements for UDI?
3. Are the barcodes compliant with the relevant standards organisation's specifications?
4. Do changes to the current labelling to incorporate barcodes meet the relevant specifications?
5. How is the variable data currently printed on labelling?
6. Is it possible to add barcode printing to the variable data?
7. Do you manufacture products that will be reprocessed and therefore require part marking?
8. How automated are the production lines?
9. How fast are the production lines?
10. What printing equipment is currently in place (on/offline)?
11. Is there verification equipment in place (on/offline)?
12. What is the budget?

Once this information is compiled, an assessment can be completed and decisions made as to the best solutions to implement for the relevant production lines.

Printing equipment

Serious consideration should be given to the type of printing equipment used for printing barcodes. It is worth looking into the different options in detail before making decisions because there are benefits and pitfalls to each one. There are five basic printer types used in barcode printing:

1. Thermal transfer: the most widely used type of printer because it produces very high-quality barcodes. The initial implementation cost would be moderate to high, but the ongoing maintenance levels are low.
2. Direct thermal: these printers produce medium to high-quality barcodes. The implementation costs would again be moderate to high with low ongoing maintenance levels.
3. Laser: gives medium to low-quality barcodes depending on the quality of the printer. The costs would be moderate, although they would be a lot higher for a better-quality code. The maintenance level would be fairly high.
4. Ink jet: produces medium-quality barcodes but the implementation costs are high. The maintenance requirements are also fairly high.
5. Dot matrix: has the lowest implementation cost but only produces low-quality barcodes with a high maintenance level.

Part marking

For multiple-use products there may be a requirement for the actual product to be directly marked with the UDI, which can be done either directly onto the product or onto something permanently applied to the product - for example, a metal plate that is attached to a machine. This would require a different type of printing, with the options dependent upon the type of products.

1. Dot peening: a low initial cost and gives a permanent mark, but it is quite slow and is impact marking, so is not suitable for all product types.
2. Laser etching: delivers a high-quality permanent mark, but there are high implementation costs and it is a non-contact method.
3. Ink jet: a high-speed, low-cost, non-contact method, but the results are not permanent. There are consumable costs involved too.
4. Electro-chemical etching: a low-cost option that does not change the surface of the product, but is slow and there are consumable costs to consider.

Verification

Once barcodes have been printed it is a good idea to check the quality and ensure that they are readable. You can check that the barcode reads with a simple barcode scanner that will just decode the symbol back to numbers and/or letters. However, it is recommended that you get a proper verification of the symbol done to ensure that the barcode is of a good quality and will be able to be read by all scanners on its journey through the supply chain.

Standards organisations such as GS1 offer their members a barcode verification service. Alternatively, there are a number of verifiers available to purchase and build into your quality systems. This could be as an offline quality check, or online as part of an automated production line.

Verification of the barcodes will also ensure that you comply with the barcode printing standards ISO/IEC 15426-1, CEN 1635, and ANSI standards X3.182-1990 and ANSI/UCC5.

UDI is happening and the healthcare sector has a lot to gain from its implementation: the improved efficiency of the supply chain will not only lead to a more cost-effective health service but, more importantly, improved patient safety.