National Consumers League


NCL Technology Issues

All about radio frequency identification (RFID)

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What is RFID?RFID – radio frequency identification – has been around for over 60 years. Today, consumers come into contact with this technology in many forms, from the passes that employees use to gain access to the buildings where they work to payment cards that don’t have to be swiped through a machine. As RFID is increasingly used in people’s daily lives, it’s important to understand what it is and how it works.

This tutorial and glossary from the National Consumers League will help you better understand RFID and how it's involved in your life.


What is RFID and how does it work?

RFID is a wireless technology that is used to identify things. It typically involves three components: a tag, a reader, and a computer system.

Sometimes referred to as a transponder, the tag consists of a microchip and a radio antenna. The chip in the tag contains information about the item that it is either attached to or that it is embedded in. The tag transmits that information to the reader using radio signals.

The reader, also called an interropgator, is a device that is designed to pick up those radio signals and deliver the information they contain to the computer system.

The computer system can use the information in a variety of ways, depending on what it is set up to do – for example, it might be to track inventory or give a person access to an office building. It may be connected to databases that contain more information linked to the item and, in some cases, to the person using it.


How big are the tags?

The tags vary in size depending on the size of the chip they contain.

Some tags are smaller than a grain of rice and can be embedded in products or labels, even planted under the skin. Others are as big as a deck of playing cards and are attached to pallets and cases. Tags also vary in how much information their chips can store or process, with inexpensive “dumb” tags having little memory or processing capacity and more costly “smart” tags having far greater computing power.


How is RFID used in the real world?

Many consumers are already familiar with one form of RFID – the toll-pass that drivers can keep inside their cars to go through toll booths without having to stop to pay.

The chip in the toll-pass sends information to a reader located in the toll booth. This information, the reader’s location, and the time and date of the reading are then transmitted to a computer system, which may be linked to databases containing other information such as the toll fee and the bank account that will be billed for the toll.

Another use of RFID that some consumers are familiar with are payment systems that allow them to wave a tag in front of a reader on a gas pump to fill up a gas tank. RFID technology is also being used to control entry into certain buildings. Some pet owners are having their dogs or cats implanted to help track them in case they get lost, and the U.S. Food and Drug Administration has approved a tag to be implanted in humans containing their patient records for use in hospitals. RFID is being used in supply chains to track the movement of products from a manufacturer to a distributor to a retailer and any points in between. Depending on their intended use, RFID systems vary in capability, the complexity and cost of the tag, the amount and sensitivity of the information that the chips contain, and the distance from which readers can pick up the signals from the tags.


How close to the tag does the reader need to be?

That depends on whether the RFID tag is passive or active.

Some tags are called passive because they don’t have their own power source. The reader powers up the tag by sending it a radio signal, and the tag responds by sending radio signals back with the information the chip contains. An active tag has its own small battery or other source of power and doesn’t require power from the reader to send a signal to it. Passive tags can be read only from a relatively short distance, from a few inches to a few yards. Active tags can generally be read from a longer distance.

The radio signals used to communicate between tags and readers can pass through objects – they don’t require a direct line of sight between them as barcodes do with bar code readers. This means that if individual items in a grocery store were tagged, it is theoretically possible to go through the checkout simply by wheeling the shopping cart by a reader, without having to unload it. As the technology advances, the ability to get consistently accurate reads is improving.


What information can be stored on the chips in the tags?

The chips in the tags may have all sorts of information on them, depending on the purpose for which the tags are used.

For example, those that control access to buildings may contain the employee’s name, job title, and information about which parts of the building the person can go. Some tags have only a unique ID code for the item they are identifying (see Understanding the EPC). The information on the chips may be linked to databases that contain more information, including about individuals. As technology advances, the chips in the tags will be able to store and process an increasing amount of information.


What about security?

As with any technology, criminals might try to exploit RFID, so security is important. For consumers, the main security concern is about RFID uses in which their personal information, such as health records or bank account numbers, is stored on the chips in the tags or in databases that are linked to them.

There are various types of security measures that can be used to protect information as it is transmitted and stored, such as encrypting it – turning it into a code that only authorized users can translate. Devices such as key fobs and wireless phones that are equipped with RFID in order to use them to pay for purchases present another security concern – what happens if they are lost or stolen? One way to prevent unauthorized use would be to have the ability to “lock” these devices so their functions can be turned off if they fall into the wrong hands.


How can RFID benefit consumers?

Convenience is one of the biggest benefits of RFID. In addition to the tags that allow drivers to pass through toll booths quickly, consumers can also use cell phones, key fobs, and credit cards that are equipped with RFID to pay for purchases simply by waving them in front of readers.

RFID tags on items can make it easier for consumers to make product returns without receipts. Similar to the way that pets can be implanted with tags to make it easier to identify them if they are lost, Alzheimer’s patients may wear tagged wrist bands in case they wander away from their caregivers. Patients in some hospitals wear them to ensure that they get the right medications, and expensive hospital equipment is being tagged so it can be located quickly and be more efficiently used.


What is an electronic product code (EPC)?

EPC stands for Electronic Product Code.  It is also sometimes called “the next generation barcode.”

It’s a unique identification code that is stored in the chip on a tag as a product goes through the supply chain. Unlike the bar codes that are commonly used on items to distinguish a can of soup from a box of crackers, the EPC can identify a specific can of soup or box of crackers by its unique ID number.


Do all RFID systems use EPC?

No, the EPC is a unique numbering system enabled by RFID and is mainly used on shipping cartons and pallets to track products from the manufacturer to the warehouse to delivery at the retail location. If individual items have tags with the EPC, the tags are usually on the packaging – on the box that contains the television a consumer buys, for instance, not on the television itself.


How can the EPC benefit consumers?

Convenience is one of the biggest benefits of the EPC.  It can also help merchants keep popular products from running out by tracking inventory and ordering re-supplies more quickly.

Some shopping carts are being equipped with readers that will communicate with tags embedded on store shelves. When the consumer walks by, a small screen on the cart will display promotions, recipes, and other information connected with those products.

Safety is another benefit. For example, tagging prescription drug bottles with the EPC at the manufacturer can help pharmacies assure that the drugs they are providing to consumers are real, not counterfeit and that the prescription drugs being dispensed are those that the doctor prescribed. Stores can use RFID to locate and remove perishable items that are past their prime or recalled items from their shelves. RFID can also help protect the public health by enabling companies to track the source of an item – like a bag of spinach or beef from a cow, in case of disease.

Do all RFID systems use EPCs? No, the EPC is a unique numbering system enabled by RFID and is mainly used on shipping cartons and pallets to track products from the manufacturer to the warehouse to delivery at the retail location. If individual items have tags with the EPC, the tags are usually on the packaging – on the box that contains the television a consumer buys, for instance, not on the television itself.


What about my privacy?

Though few individual items are presently being tagged, the use of tags is growing. As RFID use becomes more widespread, it is important to know what information, if any, will be collected, how it will be used, if it will be stored and for how long, and whether it will be shared and with whom, especially if it is or can be linked to personal information about individuals.

Tags with chips programmed with the EPC to track items through the supply chain don’t contain information about individuals. But as with barcodes today, it’s possible that information about individuals could be linked to purchasing those items. For example when consumers use store loyalty cards to get sale prices, the retailer can keep track of the types of products they buy by linking the information from the barcodes on those items to the personal information those individuals may have provided when they signed up for the cards. With that information, retailers can track the spending habits of customers in a certain zip code, or send them advertisements for certain kinds of products.

In other uses of RFID technology, information about individuals may be stored on the chips in the tags. Again, the information on the chips may also be linked with information about individuals stored in databases connected to the system. Take the toll-pass system – it’s designed to collect information about where the tag was, and when, and links that data with information in a database about whose account to bill. This information could potentially be used in ways that may raise privacy concerns. For instance, an employer who installs a toll pass in a company car and monitors the charges made against the account could track where and when an employee has driven the car on toll roads.


How do I know if RFID is being used?

Because the tags can be so small, their use may not be readily visible. Sometimes they are embedded in items – for instance, tags are being built into new tires to monitor the tire pressure for safety purposes.

Items with tags that have chips containing the EPC are marked with a symbol that contains those letters, which indicates that the manufacturer participates in a voluntary program that requires it to disclose the use of RFID technology and follow certain practices to protect consumer privacy. The symbol will usually appear on the back of the package.

In other uses of RFID, there may be disclosures on signs in the store, on product labels, or in contracts and user agreements, or there may be no notice at all. There is no U.S. federal requirement to label RFID tagged items or to disclose that RFID is being used. Some states are considering laws concerning RFID, which may include requirements to disclose its use.


Can I remove RFID or deactivate the tag?

That depends on how the tag is attached and how it is intended to be used.

If it’s embedded in an item, like a tire, it may not be possible to remove or deactivate it, or to do so without destroying the product. In other cases, removing it may be pointless. For example, if someone were to remove the RFID technology from the keyless remote for their car, it would become useless. If a tag can be easily removed or turned off, consumers may have that option.

In the case of tags with chips that contain the EPC, they are usually on the packaging and will be discarded with when the packages are thrown out. In some cases, a store clerk may remove a tag at the point of purchase, as is done now with the security tags on certain items, such as a DVD or clothing item.

If there is a choice about removing or disabling a tag, consider any benefits it provides and weigh them against any trade-offs you’d have to make. For example, if the tag is designed to make returning items easier, what is the return process without the tag? Are there other options? Is it possible to get the same or a similar item without the tag?

Also consider what privacy implications, if any, there may be in relation to the tag. Will any personal information be on the tag or linked to it? What type of information is it and how will it be used? Is it possible to get the benefits without any personal information being linked to the tag? If the tag is used as part of a payment system or for another sensitive purpose, such as providing health records, is there adequate security to prevent it from being read or used without authorization? Look for explanations about privacy and security and ask questions to make informed decisions about using products with RFID.


Where can I get more information about RFID?

Information is available from a variety of sources, and consumers can search online for more resources about RFID.

Trans Atlantic Consumer Dialogue
Consumer and privacy issues related to using RFID

Center for Democracy and Technology
Best practices for companies using RFID

Discover RFID: An consumer-oriented site about RFID technology

Guidelines for companies using the EPC

EPCglobal US

Guidelines for U.S. companies using the EPC