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Updated: Jun 30, 2025

Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children
Published on: September 11, 2018
Test Methods to Rigorously, Reproducibly, and Accurately Measure the Detection Performance of Walk-through Metal
1Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Dr., Mail Stop 8102, Gaithersburg, MD 20899, USA.
Abstract:
Walk-through metal detectors (WTMDs) are the primary tool for the detection of concealed metal contraband and threat items on a person. They are found at almost all security checkpoint stations worldwide. It is important for security that assessing the detection performance of WTMDs is done rigorously, accurately, and reproducibly. Current standardized test methods do not provide this capability. Moreover, exhaustive testing would be prohibitively expensive and slow. Test methods, test objects, and their rationale are described here that can be used to accurately and reproducibly measure the detection performance of a WTMD while rigorously exercising its detection capability. Focused selection of the most informative test parameters reduces the time required for testing by about two orders of magnitude.
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