Barcodes are central to laboratory traceability, but creating a barcode label that scans reliably in a lab is often more complicated than printing a label and applying it to a sample. Laboratories frequently work with small tubes, curved vials, microscope slides, microplates, frozen specimens, and automated handling systems—all of which can interfere with barcode readability.
A barcode may scan perfectly in a controlled environment but fail after exposure to condensation, chemical wipes, cryogenic storage, or repeated handling. In automated labs, even minor inconsistencies in barcode placement can disrupt scanning workflows.
Improving laboratory barcode scanning requires engineering the barcode, laboratory labels, and application strategy together. This article explains the key design decisions that help laboratories achieve faster, more reliable scans.
Common barcode scanning challenges in laboratories
Laboratories create scanning challenges that most retail, warehouse, and healthcare environments never face. Lab teams often need to identify samples on extremely small containers, preserve readability through harsh storage conditions, and support both manual and automated scanning workflows. A barcode that scans reliably on a corrugated box or shipping label may struggle on a frozen cryovial or curved microcentrifuge tube.
Common scanning challenges include:
- Barcodes printed too small
- Curved surfaces distort barcode images
- Frost blocks barcode readability
- Chemicals damage printed images
- Poor print contrast
- Inconsistent label placement
- Scanner compatibility issues
- Barcode abrasion from repeated handling
- Limited scan angles
- Overcrowded label designs
Most of these issues can be prevented when labs engineer barcode labels around scanning performance from the beginning.
Engineer barcode design for scanner performance.
Reliable scanning starts with barcode design. Even highly durable labels can create scanning problems if the barcode itself isn’t built for the scanner, surface area, and workflow it needs to support.
Barcode Symbologies
The first decision is barcode symbology. Many laboratories still use Code 128 because it stores alphanumeric data efficiently and works well when labels have enough horizontal space. Smaller labware often benefits from Data Matrix because it stores more data in a smaller footprint and allows omnidirectional scanning. Many labs also use QR Code for mobile workflows, though healthcare and regulated lab environments often prefer Data Matrix because of its compact size and strong error correction capabilities.
Barcode Size
Labs often reduce barcode dimensions to fit small tubes, vials, and slides, but shrinking a barcode too aggressively can create modules or bars that scanners can’t reliably distinguish. For 2D barcodes, this often means reducing the individual cell size below what the scanner’s imaging sensor can accurately resolve. For linear barcodes, extremely narrow bars can exceed the scanner’s optical resolution. Scanner depth of field also matters—some scanners perform well at close range while others struggle when operators scan from inconsistent distances.
This issue becomes even more common when teams use scanners with lower resolution sensors or longer scan distances. Barcode size should align with both the available label space and the scanner’s technical capabilities.
Quiet Zones
Quiet zones are blank spaces around the barcode that help scanners identify where the code begins and ends. When text, borders, or other design elements sit too close to the symbol, scanners may struggle to isolate the barcode from surrounding content. This issue becomes more common on small laboratory labels where teams try to maximize every available millimeter of space. Most barcode standards require minimum quiet zones based on the barcode’s x-dimension, so reducing them too aggressively can hurt scan reliability.
Print Contrast
Print contrast directly affects readability because scanners detect the difference between dark barcode elements and lighter background spaces. Most laboratory labels use black thermal transfer printing on white label stock because it creates consistent contrast for both laser scanners and 2D imaging scanners.
Problems often appear when teams print on glossy, transparent, metallic, or highly reflective materials that create glare or reduce edge definition. Low-quality printheads can also produce voids, inconsistent darkness, or feathered edges that make bars and cells harder to decode. Ribbon selection matters as well—an incompatible ribbon may not properly bond to the label surface, which can reduce image density and cause barcode degradation over time.
Strong contrast helps scanners decode barcodes faster, especially in automated workflows where scanners have limited time to capture an image.
Barcode Verification
Barcode verification helps confirm that a barcode can be consistently decoded before labels move into production. Verifiers measure factors such as contrast, modulation, axial non-uniformity, symbol defects, and edge quality based on standards like ISO/IEC 15415 for 2D codes and ISO/IEC 15416 for linear barcodes. While verification doesn’t replace real-world scanner testing, it helps identify print quality issues early before they create larger scanning problems in the lab.
Optimize barcode scanning for small and curved labware.
Barcode design won’t solve scanning issues if the physical label doesn’t fit the labware correctly. Laboratories routinely label some of the most difficult surfaces for barcode scanning, including cryovials, microcentrifuge tubes, conical tubes, microscope slides, ampoules, and microplates.
Curved surfaces often create the biggest challenge. When teams wrap a barcode too far around a small tube, scanners may struggle to read distorted bars or compressed cells. This issue becomes especially common with linear barcodes because they require a clean horizontal scan path. In many cases, compact 2D barcodes like Data Matrix perform better on smaller curved containers because they require less horizontal space.
Wrap-around labels often help solve this issue by creating a dedicated printable area while securing the label tightly to the tube. This allows teams to keep the barcode flat enough for consistent scanning while protecting the printed image. Small cap labels also work well for top-down scanning workflows in storage racks or automated retrieval systems.
Barcode placement directly affects scanner performance. Labs should position barcodes where handheld scanners, fixed scanners, or automated readers can access them quickly without rotating the sample excessively. In automated workflows, consistent barcode orientation becomes even more important because scanners expect the barcode to appear at the same angle and location every time. Better placement reduces rescans and improves throughput.
Select materials that protect barcode readability.
The right label material should protect barcode readability throughout the entire life of a sample. In laboratory environments, that often means engineering labels to withstand cold storage, chemical exposure, sterilization processes, and repeated handling without compromising scan performance.
For cryogenic workflows, labels need adhesives and face stocks that remain stable in ultra-low freezers and Liquid nitrogen environments. Materials should resist lifting, wrinkling, and cracking while maintaining a smooth barcode surface that scanners can read consistently. Teams also need to account for condensation during sample removal, since frost buildup can temporarily block scans.
Chemical resistance matters in many labs as well. Containers may be exposed to ethanol, isopropanol, xylene, bleach, and other solvents that can damage printed images. Top-coated materials paired with compatible resin thermal transfer ribbons help create stronger image durability by improving scratch resistance and chemical resistance. Adhesive dwell time also matters—many cryogenic labels require time to fully wet out on the substrate before exposure to ultra-low temperatures.
Some applications also require resistance to autoclave sterilization cycles, abrasion, and long-term storage. Laminates can add protection in certain workflows, but teams should evaluate glare carefully because highly reflective surfaces can interfere with scanner performance.
When labs choose materials based only on upfront cost or basic adhesion, barcode readability often declines over time. The right material protects scanning performance from application through final sample retrieval.
Engineer barcode labels for automated scanning systems
Automation introduces a different set of scanning requirements. A barcode that scans reliably with a handheld scanner may still create problems in automated workflows where scanners read samples at fixed angles, fixed distances, and much higher speeds where decode speed and read rate consistency become critical. Machine vision systems often operate within tight tolerances for barcode location, orientation, and lighting conditions.
Many laboratories now use automated storage systems, liquid handlers, robotic pick-and-place systems, and high-throughput workstations. These systems often rely on fixed barcode scanners or machine vision systems that expect labels to appear in highly consistent positions.
Barcode orientation becomes especially important in these environments. If one tube places the barcode slightly higher, lower, or at a different angle than the next tube, automated scanners may struggle to locate the code quickly. Standardized placement improves scan speed and reduces workflow interruptions.
Labs also need to account for scan direction. Some systems scan from the side, while others read barcodes from the top or bottom of tubes, plates, or racks. Small cap labels often support top-down scanning workflows, while side-mounted labels may work better in other automated systems.
Lighting conditions matter as well. Glossy materials, reflective laminates, and inconsistent print contrast can create glare that interferes with machine vision systems.
Before implementing automated workflows, labs should design barcode labels around the exact scanning environment. Scanner type, read distance, orientation requirements, and throughput expectations all influence barcode performance.
Test barcode labels with the scanners used in your workflow.
A barcode may look perfect in design software and still create scanning issues in real laboratory environments. Reliable performance requires testing labels with the same scanners, workflows, and environmental conditions they’ll encounter in the field.
Barcode verification typically comes first. Verification uses specialized equipment to measure barcode quality against International Organization for Standardization standards such as ISO/IEC 15416 for linear barcodes and ISO/IEC 15415 for 2D barcodes. These tests evaluate print contrast, symbol defects, edge quality, modulation, and other factors that affect scan performance. The verifier then assigns a grade that helps identify printing issues before labels move into production.
Verification only measures barcode quality under controlled conditions. Real-world validation confirms that the label performs in actual lab workflows.
That’s why we test labels with the same scanners customers use, including handheld scanners, fixed-mount scanners, machine vision systems, and automated readers. Our dedicated testing space allows us to evaluate scan distance, scan angles, throughput speed, lighting conditions, and barcode orientation before implementation.
We also test barcode performance after freeze-thaw cycles, chemical exposure, abrasion, and other environmental stressors that could impact readability over time.
Strong barcode labels don’t just meet specifications—they scan reliably in real workflows.
Engineer laboratory barcode labels for optimal scanning performance.
Reliable laboratory barcode scanning starts long before someone scans a sample. Barcode design, label placement, material selection, automation requirements, and real-world testing all influence whether a barcode scans quickly and consistently throughout a sample’s lifecycle.
Laboratories often operate in environments that make scanning more difficult—small containers, curved surfaces, cryogenic storage, chemical exposure, and automated handling systems all introduce unique challenges. Solving those challenges requires more than selecting a barcode format. It requires engineering the entire label around long-term scan performance.
For additional insight into scanner performance, explore the Dynamsoft blog. It offers a range of articles focused on barcode scanning challenges, decoding performance, and real-world optimization strategies that complement the label engineering approaches covered here.
When labels scan reliably, labs reduce rescans, improve throughput, strengthen traceability, and avoid workflow disruptions. If your lab needs barcode labels for challenging applications, we can help engineer a solution around your scanners, sample containers, environmental conditions, and workflow requirements. Start here to find the right label match for you.
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