Transportation Security Administration (TSA) scanners are advanced technologies used at airport security checkpoints to screen passengers. They identify prohibited items on individuals, enhancing safety by detecting objects that could pose a threat during air travel.
Types of Body Scanners Used
The TSA primarily utilizes two types of advanced imaging technology (AIT) for passenger screening: millimeter wave scanners and backscatter X-ray scanners. While both aim to detect concealed items, they operate on different scientific principles. Millimeter wave scanners use radio waves, whereas backscatter X-ray scanners employ very low-dose X-rays. Currently, millimeter wave technology is the most common type of body scanner found in airports.
How Millimeter Wave Scanners Operate
Millimeter wave scanners emit low-power electromagnetic waves, similar to radio waves. These waves reflect off a person’s body and any concealed objects. Receivers collect the reflected waves. Computer software processes this data to generate a generic, privacy-protective outline.
The system highlights anomalies or concealed objects on this outline, indicating potential threats. These scanners do not produce detailed images of internal body structures. Instead, they create a simplified outline with flagged areas for closer inspection. This technology detects both metallic and non-metallic items.
How Backscatter X-ray Scanners Operate
Backscatter X-ray scanners operate by emitting very low-dose X-rays that scatter off the body’s surface and any hidden objects. Detectors then capture these scattered X-rays to form an image. This technology creates a two-dimensional image that reveals items concealed under clothing.
While less common in many airports now, these systems were previously used. They provided an alternative screening method, highlighting objects based on their density and atomic number.
What Scanners Identify
TSA scanners are designed to identify various items concealed on a person’s body or within their clothing. Their primary function is to detect both metallic and non-metallic threats. This includes items such as weapons, including guns and knives, as well as explosives.
These systems are specifically configured to flag any anomalies on the surface or within the immediate clothing layers. The scanners are not intended to identify specific medical conditions or internal body structures. They focus on identifying objects that could pose a security risk during air travel.
Passenger Safety and Privacy
Concerns regarding scanner use often revolve around passenger safety and privacy. Millimeter wave technology utilizes non-ionizing radiation, which is a form of low-level radio waves, similar to those used in wireless data transmission. This technology does not use X-rays and does not contribute to a person’s ionizing radiation dose.
For privacy, the images generated by millimeter wave scanners are processed to protect passenger anonymity. The system typically displays a generic outline or avatar of the person, highlighting only areas where potential threats are detected. Passengers also retain the option to request a physical pat-down instead of undergoing a scanner screening.