NIR User Manual

Radiation detectors are used in nuclear security in an attempt to intercept illicit trafficking of radioactive or nuclear materials. In this field, several types of detectors are used to detect the presence of a source, to measure the exposure rate to men, to locate and to identify it. To test the performance of such detectors, many exposures with a radioactive source are required (typically 60), and the exposures need to be repeated with sources with different gamma-energies, and with neutron-emitting sources. For some tests, combinations of sources are used. IRMM and ITU jointly designed and built an instrument, named "NIR" that can expose a radioactive source for a defined amount of time. The instrument consists of a source holder, mounted on an electrically controlled cylinder. The cylinder pushes the source holder out of a radiation shield, and retracts the holder after the exposure time has elapsed. Unique about this instrument is the fact that it does not contain a fixed source. Instead, the user can choose any source available and mount it in the source holder. The motion of the source holder is very precisely controlled using a servo motor. It will always come to the same position, following the same motion profile. The instrument can be controlled from a distance using software running on a computer, thereby reducing exposure to operators, as compared to manually executed exposures. The instrument allows to test of several radiation detectors at the same time. The high speed of operation and precision results in a reduced total test time and an increased confidence in the test result. This document is the user manual of the instrument NIR, it contains the original instructions for transport, installation and operation.JRC.D.5-Nuclear physic