Evaluation of the effectiveness of radiation detection systems in measurement of equivalent dose rate for nuclear reactor workers

This paper introduces a practical study to evaluate and analyze the effectiveness of radiation detection systems used to measure the equivalent dose of the workers involved in Gemstones (Topaz) colour treatment process at Egypt Second Research Reactor (ETRR-2). Typically, thermoluminescence dosimeters (TLDs) are used to record the accumulated radiation dose equivalent to the periodic assessment of the health and safety of reactor workers. The accuracy of using TLDs has been evaluated in the International Atomic Energy Agency's Radiological Dosimetry Laboratory as they can be used in various nuclear environments such as nuclear reactors. This paper proposes the use of a gas-filled radiation detector, a Geiger-Muller (GM) tube, to assess the intervention of workers in handling Topaz irradiation boxes and preparing them for regular irradiation at the reactor. A comparison was made between the TLDs and the GM tube detectors and the difference in their readings and their dependence on the radiation dose rate were assessed. The difference in sub-linearity phenomena of both detectors and its effect on the GM tube values and the effect on the operator's performance to complete the filling and preparing Topaz boxes for irradiation were investigated. The difference in recording dose for both the TLD and the GM tube was taken into account based on the equation shown.