The performance criteria for active interrogation systems in Homeland Security applications are describe in this standard. These systems are intended for non-intrusive inspection of closed containers, vehicles, and packages of a wide range of types and sizes. In these systems, the contents of an inspection zone are irradiated with penetrating ionizing radiation to determine the presence of a hidden substance of interest by the analysis of stimulated secondary radiations or nuclear resonance absorption spectra that are indicative of the chemical and/or nuclidic composition of the substance of interest. The "IEEE Get Program" grants public access to view and download individual PDFs of select standards at no charge. Visit http://standards.ieee.org/about/get/index.html for details.