The use of backscatter X-ray technology for screening human subjects at airports and border crossings became more widespread after a terrorist bombing attempt involving explosives hidden near the surface of the bomber's body.
Backscatter involves analysis of the low-dosage x-ray reflections which bounce of a human target revealing the surface profile of the human form as well as any foreign objects hidden within or under the clothing of the subject. In this respect, it is a viable and reliable alternative to physical searches or "pat-downs".
The advantage of backscatter over other human screening systems is the high resolution image available at low dosages enabling the detection of small quantities of explosives that are capable of causing catastrophic failure on an aircraft.
Health and privacy concerns relating to the technology continue to be hotly debated.
Vancouver aviation security conference sees launch of millimetre wave body scanner which can operate in isolation or as part of an integrated security screening system.
