Barcodes are integral to your daily workflow, whether you’re a business, laboratory, or healthcare institution. For many businesses, they help track and trace inventory; for labs, they’re also necessary to identify samples and patient specimens. But what happens when you have problems reading your barcodes, or they fail to scan? Here are some reasons (and solutions) that might help you navigate through this unwanted situation.

Poor label placement

The most obvious culprit of an unreadable barcode is poor label placement. Imagine wrapping a 1D barcode label around the circumference of 15 mL tube. Now take a scanner and try reading the barcode. There’s no way the laser emitting from the scanner can read all the lines of the barcode if it’s wrapped around the tube. Unfortunately, samples that are labeled by one user are frequently analyzed by another later down the road (a nurse who takes a blood sample and delivers it to a medical lab to be processed, for instance), making it difficult for lab personnel to control how samples are labeled.

Solution: The best way to avoid a poorly placed barcode is to have a standard operating protocol (SOP) in place that specifies an appropriate methodology for each container that requires labeling, including the type of label, barcode, and label placement. When designing your SOP, be sure to include pictograms that make it clear how each type of tube is supposed to be labeled.

Poor barcode/scanner position

A failed barcode scan can be caused by a few things related to the position of the barcode or scanner:

The barcode might be too close or too far from the scanner, depending on the scanner’s optimal focal distance (the distance at which the barcode comes into focus).

The barcode might be located at a poor angle relative to the scanner. Mounting a scanner perpendicularly to the barcode can cause specular reflection, where light is reflected directly back at the scanner, blinding it to the signal of the barcode.

The orientation of the barcode might not be compatible with the scanner. For example, laser barcode scanners must be placed such that the laser line is perpendicular to the bars of the barcode for it to be read.

Solution: For applications requiring challenging scanning conditions, using readers with built-in autofocus is ideal, as they can adjust to a range of variable barcode distances, angles, and orientations. Employing barcode imagers instead of barcode scanners, which use cameras to read images of codes rather than the signal of the reflective laser, may also be helpful as they are less liable to suffer interference from the reflecting laser and can often read barcodes no matter the orientation. Right-angle mirrors can also reflect the light of the barcode towards the scanner; however, when using right-angle mirrors, it’s important to have a scanner that can read flipped images.

Damaged barcodes

Barcodes can be exposed to many harsh conditions, such as extreme temperatures and chemical exposure. This can make your barcodes fade or smudge, causing them to become unreadable. Barcodes can also suffer from mechanical damage, like scratches, tears, or crinkling.

Solution: Here is where choosing the right label is crucial. Using a label that’s appropriate for your application will not only make sure that it stays affixed to your container, but it will also prevent damage to the label (and barcode) from the harsh environment(s) it encounters. Remember, prevention is always worth more than a cure, especially when it comes to physically damaged labels. This also applies to the printout; not all types printouts will protect your barcodes. Thermal-transfer printers provide your labels with the greatest resistance against extreme temperatures as well as organic solvents and other chemical substances, ensuring your barcodes won’t smudge or fade over time. For the times where physical damage is unavoidable, some high-performance readers can utilize symbol reconstruction technology, which allows them to reform the original barcode from the scan lines that are still intact. Varnishing or laminating your labels will also help protect your barcodes from scratches and other damage.