Setting up a new personal dosimetry system at SCK•CEN: testing the Instadose 2 dosimeter

The SCK•CEN personal dosimetry system is nearly 30 years old, reaching the end of its life. Because this system is no longer available on the market, a new dosimetry system will be needed. One of the possible candidates is the brand new Instadose 2 dosimeter, based on the Direct Ion Storage (DIS) technology. This is a system in-between passive and active dosimetry and has some remarkable advantages compared to present systems. Instadose 2 can communicate its results through a Bluetooth connection and should no longer be sent back to the dosimetry service for reading purposes. The objective of this work is to test this system for implementation in daily routine. This encompasses practical issues, like calibration and quality control, but also some more formal type testing according to IEC 62387 international standards. This was done through a study on repeatability, backwards irradiation, angular and energy response and environmental influences. On the basis of the results obtained from the different tests, it was decided to re-calibrate the devices. Using the new calibration factors the performances of the dosimeters were substantially improved and the requirements of the IEC 62387 international standards were met in a better way.