Anyone who has traveled by plane has almost certainly gone through a metal detector. Schools, sporting events, government buildings, and concerts have all deployed these security gadgets. They’re part of a larger security system that includes cameras, door access control, and paging systems in the event of an emergency.
Metal detectors are both efficient and secure. They contribute to your safety and security in the same way as IP cameras and door access control do. This is how they function.
Behind Metal Detectors
The metal detector is based on the laws of James Clerk Maxwell (1831–1879), a Scottish physicist. He identified a link between magnetism and electricity. A coil of copper wire wrapped around a metal nail is an example of the relationship. The metal nail becomes magnetic when current is introduced to the coil.
A magnetic field is created when an electric pulse is transmitted through a coil of wire. When the field collides with a metal object, it reflects back and can be detected using a second wire coil. The size and timing of the detected pulse are utilized to determine the object’s size and position.
How They Work
Pulse induction (PI) technology is commonly used in walk-through metal detectors. Powerful, quick bursts (pulses) of current are sent through the coil of wire by the PI systems. A brief magnetic field is generated by each pulse. A reflected magnetic field is formed when a piece of metal travels through a magnetic field. This magnetic field subsequently reacts with the receiver coil, causing the alarm system to go off. This starting spike lasts a few microseconds and causes a current to flow through the coil. The reflected pulse is the succeeding current that lasts roughly 30 microseconds.
A typical PI-based metal detector sends roughly 100 pulses per second; however, this might vary depending on the brand and type, ranging from about 25 to over 1,000 pulses per second.
The enormous magnetic fields created by walk-through metal detectors fill the whole space inside the rectangular arch of the metal detector. If a person walks through the metal detector and the alert goes off, airport security is notified that this individual may be concealing a dangerous metal-based weapon, such as a knife or a gun, and additional investigation is carried out.
Metal detector Archway gate with numerous zones can not only sound an alarm but also tell a security officer where the metal object is situated.
Multiple coils in multi-zone walk-through metal detectors generate a separate detecting zone. They are capable of detecting several things and displaying all of the locations where they can be found. Systems with up to 33 zones are available. The alert lights on the unit’s side make it easier for the security guard to locate the object. Take a peek at our video on “How Walk-through Metal Detectors Work” to learn more.
Walk-Through Metal Detectors are Safe and Effective
“Even though magnetic fields [produced by metal detectors] are a form of radiation, the radiation the equipment generates is nonionizing… [and] does not cause biological damage,” the Health Physics Society noted in a fact page on airport security. As a result, even repeated exposure to metal detectors poses no risk of radiation.” With this in mind, metal detectors in airports, schools, and companies are a very effective and safe way of enforcing security.
Magnetic fields are used by walk-through metal detectors to detect metal that goes through them. Maxwell’s equations are at the heart of how they function. Multiple detection zones are included in the most recent detectors, allowing them to pinpoint the exact location of the metal that is producing the alarm. They’ve been shown to be a safe and effective way to keep things secure.