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N42-2011 Radiation Portal Monitor

ANSI/IEEE N42.42 Standard project

This document is an example of output from gross counting radiation portal monitor (RM).

  • The RPM has four gamma and two a neutron radiation detectors, named according to DNDO conventions (e.g., Aa1, Ba1).
  • Each of the gamma radiation detectors has three energy windows.
  • The detectors are sampled every 100 ms.
  • The document represents one non-alarmed occupancy, consisting of seven time slices: the RPM is occupied in the third, fourth, and fifth slices; the first and second, and sixth and seventh slices are pre- and post-occupancy data.
  • In addition, the same example is provided with an additional fragment and shows the <AnalysisResults> element resulting from an alarmed occupancy, with both a gamma alarm (from three detectors), and a neutron alarm (from one detector only) together with a usage of the <NuclideIdentifiedIndicator> element resulting from and RPM and limited spectroscopic radionuclide categorization capability

Radiation portal monitor with no alarm file:

Radiation portal monitor with an alarm file:


Created March 3, 2011, Updated November 15, 2019