Professional EAS tag manufacturer
FAQ about EAS labels
-Shield by metal object
For the metal have a strong reflection of electromagnetic waves, the EAS signal will be weakened when the label near metal. So the detection range will be reduced. When interference is serious, it will make the antenna failing in alarm

Most systems can be circumvented by placing the tagged goods in a bag lined with aluminum foil. The booster bag will act as a Faraday cage, shielding the tags from the antennas. Although some vendors claim that their EAS systems cannot be defeated by bags shielded with aluminum foil, a sufficient amount of shielding will defeat all standard systems. 
Although the amount of shielding required depends on the system, its sensitivity, the distance and orientation of the tags with relative to its antennas, total enclosure of tags is not strictly necessary. Indeed, some shoplifters use clothes lined with aluminum foil. Low-frequency magnetic systems will require more shielding than radio-frequency systems due to their use of near-field magnetic coupling. 
The shielding technique is well-known amongst shoplifters and store owners. Some countries have specific laws against it.[7][10] In any case, possession of such a bag demonstrates a prior-intent to commit a crime, which in many jurisdictions raises shoplifting from misdemeanor to felony status, as they are considered a "burglary tool."[11]
To deter the use of booster bags, some stores have add-on metal detector systems which sense metallic surfaces.
Vikson has developed a new absorbing material to deter this illegal technology. The new material takes silica gel as a carrier, added with high-performance nano-electromagnetic absorbing materials
It will completely eliminate full band of electromagnetic of 10MHz ~30GHz..

But for the cost factor, currently it only be used on hard tags. 

-Technical principles of EAS label (8.2Mhz)
*the RF soft label is consists of two conductive aluminum coils to form a loop. The Peripheral coil forms the inductance, and the central flat part plate formed a capacitor. The middles of the insulating plastic film will make them separated, to form a passive LC circuit (L- inductance, c- capacitance)  
When the RF label near the RF sensor, strong electromagnetic fields emitted by the antenna will make the LC circuit produce self-excited oscillation. At this time, the RF sensor will detect the oscillation, which will trigger alarm.

The use of an external electromagnetic field so that the use of strong self-excited oscillation circuit generates lc, while adding high-voltage (200 ~ 300v ac) the film breakdown. When lc shock, vibration signal detection equipment will produce an alarm. When decoded by decoder board high-voltage (200 ~ 300v AC) makes two concave film Click to wear, causing the circuit is turned on, reset the alarm.
The deactivator will make the label inactivated through 200~300V AC.  The high voltage will breakdown the two nodes on the label film, to switch on the circuit, and then the label is inactivated.

-Decoding failed
In race cases, the RF label may not be decoded in one time, which means the labels still have the ability to trigger alarm. This may bring some troubles to consumers and businesses, so Vikson brings a new RF deactivator with alarm function. The new alarm function will give prompt if the label is not decoded normally.

-Static electricity
For the RF label will be decoded by voltage, so if static electricity is strong enough, it may even have the opportunity to kill the label. 
When we should pay attention to anti-static?
* On carpet
* Printer