Full-body scanners have become a crucial component in modern security systems, particularly in airports and other high-security areas. These devices are designed to detect objects on or inside a person's
body without the need for physical contact or the removal of clothing. The evolution of full-body scanners has been driven by the need to enhance security measures, especially following various airliner bombing attempts in the 2000s.
Early Development and Adoption
The development of full-body scanners began in earnest in the 1990s, with significant contributions from the Pacific Northwest National Laboratory (PNNL) in Richland, Washington. PNNL developed the first millimeter-wave full-body scanner, which utilized 3-D holographic-imagery technology. This innovation was supported by research and development funding from the Transportation Security Administration (TSA) and the Federal Aviation Administration (FAA).
By 2002, a Silicon Valley startup, SafeView, Inc., had obtained an exclusive license to commercialize PNNL's technology. SafeView developed a production-ready millimeter body scanner system, which included software for scanner control, threat detection, and object recognition. These scanners were trialed at various locations worldwide, including international airports and government buildings.
Technological Advancements
Full-body scanners have evolved to incorporate three distinct technologies: millimeter wave scanners, backscatter X-ray scanners, and transmission X-ray scanners. Millimeter wave scanners use non-ionizing electromagnetic radiation, similar to that used by wireless data transmitters. These scanners do not generate ionizing radiation, making them a safer option for frequent use.
Backscatter X-ray scanners, on the other hand, use low-dose radiation to detect both metallic and non-metallic objects. Despite their effectiveness, concerns about radiation exposure have led to their ban in several countries. Transmission X-ray scanners use higher dosage penetrating radiation, allowing for the detection of objects hidden inside the body.
Privacy and Safety Concerns
The implementation of full-body scanners has not been without controversy. Privacy concerns have been raised, particularly regarding the display of images that resemble virtual strip searches. To address these issues, newer technologies have been developed to provide less intrusive images, such as cartoon-like representations of the person being scanned.
Safety concerns, particularly regarding radiation exposure, have also been a topic of debate. While millimeter wave scanners are considered safe, the use of X-ray-based scanners has been scrutinized. Regulatory bodies have established standards to ensure that radiation doses remain within safe limits, but the debate over their safety continues.
Overall, full-body scanners have become an integral part of security infrastructure, balancing the need for safety with concerns over privacy and health.
