Case History: Major Midwest Corrugated Plant
The client company, a major corrugated plant in the Midwest was having a problem with their barcodes. Their portable verifier was telling them everything was fine, but one of their customers was complaining.
Their customer was using their boxes on a sortation line, and the scanners weren’t reading a lot of the ITF14 barcodes.
The Quality Control manager at the corrugated plant felt confident the barcodes were fine—they weren’t getting complaints from other customers, and the scanner in their own palletizing area was reading their barcodes no problem.
But one of his technicians mentioned they were sometimes getting widely varying results from their verifier. Sometimes it would return a C grade, sometimes an A, sometimes an F, all on the same barcode and often just a few seconds apart. Could there actually be a problem?
We met at the client’s plant and inspected their verifiers—several brand new portable verifiers, most of them with the calibration patches and documentation still unopened in the shipping boxes.
The client didn’t know that their portable verifiers were unable to test for contrast or reflectivity because of the gun-type scanning devices. This is because the gun does not scan the barcode at a fixed distance or angle. The reflectance parameters in a normal ANSI/ISO verification test are simply disabled when the gun scanner is plugged in, so the test results simply don’t factor in these attributes.
Furthermore, the client was unaware that barcodes printed on corrugated are almost never better than a D grade due to the poor contrast and reflectance characteristics of corrugated material. In other words their verifiers did not test for the most important qualities of their barcodes.
If contrast and reflectance are not tested as part of barcode verification, the test results can be (and usually are) optimistic. When it comes to managing barcode-related risk and liability, you don’t want a verification report to be optimistic or pessimistic—you want it to be truthful because there can be significant liabilities at stake—you want customers to be satisfied and loyal.
We started by unplugging the gun devices from their verifiers and replacing them with the mouse wands I brought with me. Their ITF14 symbols were achieving a solid D on Symbol Contrast but getting varying results, ranging from A to F on Defects.
Upon visual inspection, we could see that symbol quality varied from bottom to top. This explained the widely varying results with the gun imager. What about their customer’s inability to successfully scan these symbols?
The customer has older laser scanners, which are notoriously unforgiving of symbol defects. The scanners on their sortation line just happen to hit these barcodes in their lowest quality area, near the bottom of the symbol. Newer area imagers would have more vertical redundancy and be more forgiving.
Outcomes: The client has purchased ISO-compliant verifiers that eliminate all the variables and unknowns in their barcode testing. Initially their operators were upset to discover that their barcodes are not nearly as good as they thought, because of the “optimism” of their old, non-compliant verifiers but the more reliable symbol quality information has given them improved tools to evaluate and adjust their printing process. They haven’t had a barcode-related customer complaint since acquiring the new equipment.