Effectiveness
The efficacy of millimeter wave scanners in detecting threatening objects has been questioned. Formal studies demonstrated the relative inability of these scanners in detecting objects—dangerous or not—on the person being scanned. Additionally, some studies suggested that the cost–benefit ratios of these scanners is poor. As of January 2011, there had been no report of a terrorist capture as a result of a body scanner. In a series of repeated tests, the body scanners were unable to detect a handgun hidden in an undercover agent's undergarments.
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