Empowering research in of nuclear industry
On the basis of different measurement principles, two prototype instruments of energy/direction spectrometers were developed that complement each other in the exploration of unknown radiation fields in nuclear industry. The instruments were used and derived spectra allowed the calculation of the reference values for energy- and direction-dependent quantities of the neutron radiation. These quantities will ultimately lead to the estimation of personal dose equivalent and effective dose that constitute key measures for the radiation protection of workers. The instrumentation involves a silicon detector-based direction spectrometer that includes six detector capsules, each containing a stack of four silicon detectors. The capsules are mounted onto the surface of a 30cm-diameter polyethylene sphere. The direction spectrometer with superheated drop detectors has a "telescope design" and the response matrix of the full detector set-up was specified by measurements. Although validation of the first device has not been completed yet, the follow-up devices were extensively tested in all radiation fields. The spectrometers are available for use in research activities upon request. The project also gathered information on the technical and dosimetric performance of several devices and instruments, some of which are commercially used. This equipment included area monitors, active electronic personal dosemeters and other personal dosimeters. The responses of area motors were satisfactory, with a slight under-estimation of ambient dose equivalent in harder spectra and generally good estimation of personal dose equivalent or effective dose. On the other hand, the response of dosemeters varied a lot, showing a better response in hard spectra and over-response in soft spectra. Finally, Active Personal Dosemeters (APDs) were found to have a much lower detection limit than passive ones and almost similar spread of responses. All dosimetric and technical performance has been published in open literature.
