We Answer Customers' Top 15 RFID Questions

Top RFID questions

We often refer to our Sales Representatives as our “boots on the ground,” but in reality, they also are our eyes and ears of the customers. So, what better place to look when searching for our next blog topic than to our not-so-secret weapons who get the most “face time” with customers. That’s exactly what I did and with their help, we put together the following list of top RFID questions they hear from customers.

1. What is the difference between an RFID “tag” and an RFID “inlay?”

Great place to start. Think of an RFID tag having a construction. For example, the first layer is the substrate or material that can be printed. The second layer is the actual RFID inlay, and the last layer is the attachment adhesive. Whereas the RFID inlay is a component of the RFID tag. It consists of the integrated circuit (IC), antenna, and substrate.

2. What is the lifespan of an RFID tag?

Unfortunately, the answer to many of these questions will be “it depends.” Very little in RFID is cut and dried. For example, are we talking about active or passive RFID tags? Passive RFID tags will label much, much longer than active RFID tags because the active RFID tag relies on a battery and the passive RFID tags do not.

3. Can an RFID tag read through walls or people?

That depends on what the walls are made of. Are they made of metal? The answer then is no; however, if they are simply drywall then the answer is yes. RFID also has a difficult time reading through people because the body is more than 60% water and water absorbs RF energy.

4. What are the benefits of using RFID versus barcode?

This question alone can be (and has been) the subject of its own blog article. The primary benefits of using RFID versus barcode include not having to have a line of sight when reading the RFID tag, being able to read many tags at once versus scanning one barcode at a time, having the ability to store more information on an RFID tag than what can be put on a barcode tag and being able to read the RFID tag from further away than a barcode tag.

5. Do RFID tags work on liquid filled containers?

Yet another “it depends” answer. UHF, or ultra-high frequency RFID tags do not work well on liquid filled containers because the liquid absorbs the RF waves; however, HF, or high frequency RFID tags work much better on liquid filled containers but have a much shorter read range.

6. Can I walk into a room and read all my asset tags automatically?

It depends on the configuration of the room, the location of the assets, i.e., are they out or are they in a metal storage closet, the composition of the assets, i.e., metal, plastic, both? It is important to set realistic expectations and objectives when looking at implementing an RFID system. The RFID experts at Metalcraft can help guide you through this process.

7. Can RFID read through metal?

Simple answer – no, RFID cannot read through metal. However, using specialized RFID inlays like Metalcraft’s Universal RFID tags, RFID can read on metal surfaces.

8. Do RFID tags last long outdoors?

This time it depends on the RFID tag selected. For example, a paper RFID tag is not going to last as long outdoors as a polyester tag will. It also depends on what other environmental conditions the tag will be exposed to and what the life expectancy of the tag construction is.

9. If I have a lot of RFID tags in an area, how can I find a specific one?

This can be as simple as using a function on most readers called Geiger. Using the software set a filter with the serial number of the RFID tag you are looking for. The Geiger feature will help locate the asset by zeroing in on that tag and alerting the user when it has been found.

10. What is the approximate cost of an RFID implementation (readers, tags, software)?

It’s appropriate that our last question is another “it depends” answer. RFID implementations are definitely not one-size-fits-all; therefore, the approximate cost of an implementation is across the board. How complex is the implementation? How many items need to be tracked? Can a standard tag be used or will it require a custom RFID tag? Is there existing software or will that need to be customized for the application? How many readers will be needed? What types of readers will be needed – handheld or fixed? Will an integrator be involved? There are basic systems available on the market where a company could get started with RFID for less than $5,000; however, we do need to emphasize the importance of qualification for both the technology being used and the identification product being used to make sure the application is successful.

11. Why would I use RFID for tracking assets?

Organizations face significant time and cost challenges to track the location, quantity, condition, maintenance, and depreciation status of their fixed and mobile assets. RFID is a very fast and efficient approach that doesn’t require line of site in order to read the serial number programmed to the tag that is associated with the asset.

Other advantages include the ability to read numerous tags at once instead of one at a time as with other automated identification technologies such as bar code. Data redundancy is also an advantage, i.e. programming the same number into the bar code as the RFID tag or you could actually program two different numbers and track different information.

12. How and where do you attach RFID tags on wood, plastic and metal objects?

Each material requires a slightly different approach to ensure proper adhesion of the RFID tag to the asset. For example, wood can be rough and requires a thicker adhesive that can flow into the pores and grain of the wood to “wet the surface” and create a powerful, long-lasting bond.

Plastic materials require low surface energy acrylic adhesives that wet out on the smooth surface.

For metal surfaces a special RFID tag is necessary. Metalcraft offers an entire family of on-metal RFID tags to meets your project's needs.

13. My assets are stacked in cardboard boxes in our warehouse and trucks. Where is the best place to attach a tag so I can be sure to read all of the items?

The answer first depends on the contents of the boxes. Wood, paper and plastic items in boxes are relatively easy to read, but should still be tested on-site. Metallic and liquid contents present more of a challenge and will require a more specialized tag, i.e. Metalcraft’s Universal RFID Asset Tag and testing to see how items packed in a box impact read range and read rates. In some cases, the size or shape of the box may need to change to make sure each part with an RFID label is electronically visible from the outside of the larger box.

14. In general, is there a "best" location to attach the tags?

The best place to put an RFID tag is an area that is electronically in the line of sight for the radio frequency waves to travel from the reader to the tag and return. RF waves can travel through dry wood, paper and plastic; but not metal or liquids. This means you can put a tag inside or under wooden furniture and cabinets and still read from above; however, you can’t put RFID tags inside metal cabinets and expect it to work.

15. Does "noise" from equipment in the area affect the read range of the tags?

Radio frequency (RF) noise is usually not a problem in most facilities; however, this should not be assumed and testing is highly recommended. This is also one of the benefits of working with an integrator who can help diagnose any of these issues and design a system that will minimize the interference.