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N42-2011 Spectroscopic Radiation Portal Monitor

ANSI/IEEE N42.42 Standard project

This is an example of a Spectroscopic Radiation Portal Monitor (SRPM) document.

  • The SPRM's detectors are named according to DNDO conventions. There are two pillars A and B, each containing one HPGe gamma radiation detector (Aa1 and Ba1) and one a neutron radiation detector (Aa1N and Ba1N). The SRPM can determine occupant (i.e., the measured item) presence and speed, and allows entry of occupant metadata; in this case, the container identification and manifest.
  • The example document records a single occupancy:
    • First, the applicable background data are recorded
    • Six one second measurements (i.e., time slices) are recorded: the first two unoccupied, the third and fourth occupied, and the fifth and sixth unoccupied.
    • For the two occupied measurements, the occupant's position (relative to the SRPM) and speed are recorded via <RadItemState>.
    • The sum of the two occupied measurements is recorded via <DerivedData>.
    • The analysis of the summed data is recorded. The analysis resulted in an alarm due to the identification of C0-57 and Cs-137.

Spectroscopic radiation portal monitor file:


Created March 3, 2011, Updated March 13, 2020