Electronic article surveillance (EAS) is a commonly used technological protection method for apparel and merchandise in the retail industry. EAS consists of magnetic, acousto-magnetic, radio frequency, microwave systems, and source tagging. Created in the mid-sixties, EAS provided a practical solution to loss prevention executives: a physical deterrent against shoplifters. With installation of EAS systems, retailers can greatly reduce theft within stores. A casual shoplifter could be caught because of EAS tags, or may refrain from shoplifting altogether.

EAS systems are used to identify items that go through a gated area, which then sounds an alarm to alert the store of unauthorized removal of an item. EAS hard tags are reusable and can be removed using a detacher. Paper tags are disposable and can be deactivated by swiping the tag over a pad or using a handheld scanner, which authorizes the item to leave the store. Without proper deactivation or removal of a tag, an alarm will sound when an item passes through a store’s security gates.

Magnetic systems are activated through demagnetization and therefore deactivated with magnetization. These tags are suitable for library items because they can be reactivated upon return. Magnetic tags are small and have a low cost, making them suitable for low value goods.

Acousto-magnetic tags are thicker and have better detection rates than magnetic tags. These tags are made up of two strips: one magnetostrictive, ferromagnetic amorphous metal and one magnetically semi-hard metallic strip. Acousto-magnetic tags use a transmitter to create a surveillance area where tags and labels are detected. A radio frequency signal pulse is sent out by the transmitter and energizes a tag in the surveillance zone. The tag responds when the pulse ends and emits a single frequency signal.

Radio Frequency EAS system functions through a small, disposable electronic circuit and antenna that is attached to a product. This antenna responds to a specific frequency emitted by a transmitter antenna, or pedestal. The response from the label is picked up by an adjacent receiver antenna. This processes the label response signal and will trigger an alarm when it matches specific criteria. RF consists of an LC (inductor/capacitor) circuit with a resonance peak ranging from 1.75MHz to 9.5MHz. The most commonly used frequency, 8.2MHz, can be deactivated by a strong electromagnetic field, which will create voltages that exceed its breakdown voltage, thereby destroying the capacitor.

Microwave systems are permanent tags, mostly used in apparel, that contain one microwave and one electrostatic antenna. The tag emits combinations of signals from a low-frequency (about 100 kHz) field and a microwave field, which then trigger the alarm.

Source tagging refers to the embedding of EAS security labels at the source, be it the manufacturer or the supplier. This saves the retailer time and labor expenses from having to apply tags. Labels can be implemented within product packaging, making them more difficult to remove, and without ruining the product aesthetics.

EAS systems vary in cost, depending on the system type, size of the store, and amount of merchandise being protected. Retailers can compare the amount of inventory shortage before and after EAS installation to justify its cost, and they will find that they can benefit from its return on investment.