One of the most common questions end users ask RFID providers is: How do I tag this item?
"Customers routinely look for options available for tagging assets that they wish to gain visibility within their operations," says John Poplawski, product development manager at RFID tag provider William Frick & Co. "Most of them lack the knowledge of specific designs. They just understand what the tag needs to do—identify an asset—and what it needs to endure or survive while in use."
Avery Dennison also receives many questions from customers about attaching tags, according to George Dyche, the tag supplier's director of RFID product management. Among the most common queries: Can RFID tags be attached directly to metal? Can they be bent around cylindrical objects? Can RFID be applied at frozen temperatures? What types of adhesives are used to attach tags to plastic or rubber materials? Can the label be easily removed from an item without damaging the product, but strong enough to stay on the product during handling in the supply chain? Can the RFID tag be embedded in an injection-molding process? Will the label remain attached at high and low temperatures under humid conditions?
The answer to these questions is that just about any asset, part, product or other item can be identified, tracked and managed using an ultrahigh-frequency RFID tag. But tagging methods vary, based on an item's shape, size, material and texture, as well as the environmental conditions in which it will be tracked.
Among the key issues that must be considered, Poplawski says, are:
• the size of the asset to be tagged and the footprint available to receive the tag
• the surface of the asset to be tagged, such as metal, plastic, cloth, living tissue (nursery stock, farm livestock, lab animal, pets, infants), wet paint, wet chemical coating, chemically treated, abrasive
• the duration of time the asset needs to be tagged—short or long term, permanent or temporary
• the duration of time the item will be exposed to environmental conditions, such as extreme temperatures, moisture, chemicals, abrasion, dust, human contact, pressure, salt water, animal exposure, outdoor ultraviolet exposure and weather conditions, industrial processing, temperature shock (going from hot to cold and back), flash freezing (dry ice), and lab testing
• the asset's temperature at the time of tagging; for example, hot molded products just out of the mold, or frozen consumer vending products
There are also performance considerations, Poplawski says, including read distance, tag orientation, the type of readers that will collect the data, the amount of time required to read or write to the tag, how many tags will be read at a time, how quickly this will be done, and how fast the tag needs to be attached to the product.