Why Do Barcodes Misread?

Some of the reasons barcodes misread:

•Design file mistakes

•Poor print quality

•Post-production processes

•Damage

Design File Mistakes

• Failure to impose bar width

reduction (see image)

• Wrong symbology

• X dimension is too small

• Quiet Zone(s) too small or violated

• Design file resolution cannot be executed by the printer

Poor Print Quality

• Barcode in ladder orientation

• Thermal head temperature too low or too high

•Bad “housekeeping”—printer or print materials dirty

• Print speed too fast

• Unacceptable color

This UPC is printed in a color that is invisible to the scanner

Post Production Processes

• Shrink wrap partially obscures barcode

• Carton folding or gluing mistakes

• Variable data (date codes, lot number, etc.) over-write the barcode

• Product final finishing obscures or damages the barcode (such as blister pack, hang tag or header card affixing)

Barcode Damage

• Barcode abraded or scratched in handling

• Dirt or packaging dust obscures all or part of the barcode

• Punctures, tears or creases due to rough handling

Barcode Misread Types

• Non-read: barcode fails to scan

• Misread:

poor print quality causes barcode to scan wrong data

barcode scans fine but barcode contains the wrong data

Barcode Misread: the Perfect Storm

When a retail barcode misreads:

• The retailer doesn’t know what they sold

• The retailer doesn’t know what to replenish

In this UPC the human readable characters do not match the encoded data. Which is correct? Maybe neither—but either way it is a major problem.

Barcode Misread: the Perfect Storm

When a healthcare barcode misreads:

• patient and drug match fails or a false match could occur

• trading partner communications delayed

• drug safety compromised

Misreads: the worst problem Misreads can go undetected because nothing is apparently wrong!

• the scanner “beeps”

•no signal of an apparent problem

• the problem—if detected at all-- seems to happen after that

This UPC does not decode because it has a bar missing on the right side.

Misreads: a Stealth Problem

• Misreads go undetected in verification

Because most verifiers only read the encoded data, misreads are seldom detected

The Axicon 15000 is the only verifier that reads and compares the match between the encoded data and the OCR human readables

Non-reads: the “Best” Problem

• Non-read is the preferred problem

– Self-signaling: you know something is wrong

–Post production processes are often detectable

–Many print quality problems are detectable

– The process of finding a solution is immediate

Misread Detected: What Next?

• Use an ISO compliant verifier to identify the cause

• A scanner cannot reliably detect misreads or predict the behavior of other scanners

• Seek expert assistance to understand the ISO verification report

We can help…

Barcode-Test LLC

• Independent ISO compliant testing services

• Barcode quality seminars and webinars

• Verification equipment sales and support

• Plain English assistance with verification reports

Barcode-Test LLC – www.barcode-test.com – 630-235-6077 – lab@barcode-test.com