Security as tight as your clothing
The device at Huaihai Road M. Metro station
The Metro will soon be using an imaging device for passenger security checks.
The device, based on passive terahertz imaging technology, can detect dangerous materials hidden under people’s clothing.
Passengers only need to walk through a curved walkway to be checked, and if suspicious objects are detected, the device informs security staff.
The first devices are being installed at Huaihai Road M. and the Natural History Museum stations on Line 13.
Bowei Thaherz Information Technology Co, the company that makes the devices, said they emit no radiation at all. Terahertz waves, with wavelengths between microwaves and infrared, are produced by the human body and can pass through thin fabrics and plastics. When objects block the waves, their shapes and positions are indicated.
While most scanners react only to metal objects, this can analyze liquids, gels, ceramics and powder. It takes only three seconds to check each person.
The device is already in use at some subway stations in Beijing, and has been used at large international events such as the China International Import Expo.
