The ISO barcode quality specification for testing and grading of linear barcodes is often misquoted and misunderstood.

Two frequently misrepresented parameters for ISO 15416 are the ten-scan average and the 660nm wavelength requirement for light source. Neither of them is hard-wired into the ISO Barcode Quality specification.

Ten Scan average is not always required for ISO Barcode Quality 

The main text of the ANSI/CEN/ISO specification does indeed state that the Overall Symbol Grade is based on a ten scan average, but the appended language states that when there is low possibility of variability in the barcode—for example if it is very short—the number of scans per symbol can be reduced to as few as 2. See Annex G and J.

Then there’s the requirement that verification be done in 660nm red light. Actually the ISO specification does not require any particular wavelength of light for verification. What it says is that verification should be performed in the same wavelength as the scanner that will ultimately decode the symbol. Certainly most of the scanners out there are built with 660nm + 10nm but not all of them are. The wavelength is specified in the industry application specification—not in the ISO/IEC 15416 specification. Thus it is not always wrong to verify in some other wavelength, such as white light or infra red.

ISO Barcode Quality testing does not require verifying in red light

These apparent discrepancies do not discredit ISO/IEC 15416. The ISO Barcode Quality specification knowingly attempts to do the impossible: to nail down variables in a highly diverse world. Some of these variables just won’t be nailed down—and in addition to that, scanning technology is evolving and improving. The specification is meant to give shape and direction to barcode quality and to make barcode symbol performance predictable and repeatable.

High speed conveyer situations are one example where a verification system will deviate from ISO/IEC 15416. Often these are for automated, unattended verification on variable printing systems where the barcodes are sequenced, not repetitions of the same encoded data. Lighting can be a major concern for two primary reasons:

 

  1. Ambient light can be intense and variable, and not optional. The work area must be well illuminated. Work areas may have high-intensity sodium illumination, mercury vapor, or fluorescent. Each system has spectral differences. Verification lighting needs to overcome ambient light. Sometimes white light is the best available technology.

 

  1. The high speed nature of the situation also required very intense light to strobe and “freeze” the passing barcode images.

 ISO Barcode Quality verification does not ignore common sense

If the barcodes are always black on white, color contrast is unlikely to be an issue. Using white light can often be justified in this way.

This is not bending the rules—this is making use of flexibility built into the rules—even ones that are considered “bedrock”. It is not always possible to follow ISO/IEC 15416 (or ISO/IEC 15415 for verification of 2D symbols), whether for technical or economic reasons. Good faith must always be the cornerstone. The ultimate goal is to produce predictably high quality, high performing barcodes that meet the requirements of the trading partners in the supply chain, including the customer and the retailer.

 

 

 

 

 

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3db Barcode Testimonial

Our company (an advanced software company) recently worked with Barcode Test to source a barcode verifier.  Not long ago, we were awarded a contract requiring products to be marked with IUIDs in accordance with MIL-STD-130.  For that standard, marking labels must pass a verification test that evaluates many variables (contrast, size, clarity, syntax, modularity, and more).  After a thorough search, we reduced our options to a select few.

In our search for a verifier, the Axicon line caught our attention.  Barcode Test is our regional reseller for this product.   From the beginning, they were very prompt with their responses.  We ended up having a quick call with John Nachtrieb to go over our needs.  John was extremely easy to work with and provided a lot of great information.  He was very knowledgeable on the matter and was quick to offer up a demo unit (free of charge).

Upon receiving the demo verifier and testing it, a few questions arose.  John joined a call with us and answered all our questions.  Ultimately, the Axicon verifier wasn’t the best fit for us, so we shipped the demo back.  John was completely understanding.  A few weeks later, Barcode Test reached back out with another possible verifier for us to try.  While they didn’t sell that brand, they just wanted to help us find the best option that met our needs. They even offered to send us the unit that they have in-house to see if it worked to our liking. 

Barcode Test is truly a great company to work with.  Their service and willingness to help the customer are far beyond what you typically get from other companies.  They are experts in barcode quality assurance and seem willing to help in any way they can (even if that means not getting a sale and recommending another option that better fits the customer’s needs).  If anyone is in the market for barcode verification/scanning services or products, I would highly recommend giving Barcode Test a call.

Regards,

Production Manager