Universal product codes (UPC) are part of an intricate system of identifying trade items throughout the globe. According to the EDI Center, the 12-digit UPC codes are the dominant standard in the United States, while the 13-digit expanded UPC European article number (EAN) is widely used in the rest of the world. There’s also an additional Global Trade Item Number (GTIN), which identifies a product across organizational boundaries and countries and is also often encoded within a UPC or EAN bar code. These necessary but complex coding systems may confuse the first-time retailer, and a few other inherent disadvantages come with using UPC bar codes, which a retailer must watch for and manage.

Poor Print Quality

One disadvantage to using UPC bar codes is that the system relies on having well-printed, undamaged bar codes for bar code readers to scan. According to "PlantServices" magazine, if the print quality of a bar code is poor, or if the color contrast between the bar code and the paper’s color is too close, it may be too difficult to read.

Expensive Scanning Equipment

Generally, two types of bar code scanners or readers exist, according to "PlantServices": contact and noncontact. Contact scanners are usually hand-held wands or light pens and are the least expensive type. However, contact wand scanning requires actual contact with the bar code and a bit of skill. Thus, it increases scanning time.

Noncontact laser bar code scanners are thus the industry-preferred type. They come in two forms: fixed and moving beam lasers. These are more effective and efficient for operators or cashiers, especially when handling large volumes of products. Noncontact scanners can more easily discern bar codes of poor quality print or those that are etched, coated or recessed. But this scanner technology is more expensive.

Large Inventory Inefficiencies

For all its tracking advantages, using UPC bar codes is still not as quick and efficient as using the newer radio frequency identification (RFID) technology. This is the latest method championed by the GS1 US, the American organization espousing the use of the global GS1 System, which incorporates the EAN/UCC, UPC and GTIN coding systems.

According to IDAutomation, the tags used in RFID technology can be read no matter where and how it is placed on an item. Pallets in a huge warehouse can be located and inventoried this way, no matter where they are situated, because the radio waves used are strong enough to establish communication between the RFID reader and tag. This isn't so with using UPC bar codes. Like in cashier work, automated inventory tracking becomes difficult in large volumes because bar code scanning still has to be done within the line of sight of the reader.