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Ensuring the effective use of a dose calibrator used for the practice of nuclear medicine, and the injection of the correct dose to the patient is the subject of a long traceable calibration chain, which serves to establish the relationship between the values of the activity indicated by the dose calibrator and the activity corresponding to ISO 2919 certified sealed sources whose activity is known with an uncertainty of less than 1 %. Our calibration program consists in carrying out various quality control on the CRC 55TR activimeter, namely the daily control which is carried out in the absence of any radioactive source, then the fidelity control carried out by a source of 37Cs and a source of 60Co, then the reproducibility check performed with a 137Cs source, and finally the linearity check performed with a 99mTc source. In our case the results obtained from the specific tests used to verify the proper functioning of the Capintec CRC 55tR activimeter in a nuclear medicine service in Morocco, shows an agreement with international standards so that the measurement of activities is done with significant results, in addition, to guarantee the metrological quality of the measurements delivered, Our laboratory registers in an accreditation process according to ISO 17025.

Quality control of dose calibrators is essential to evaluate the accuracy of the instrument response. In this work, a GUI (Graphical User Interface) has been developed to facilitate performing and recording quality control tests of dose calibrators. The interface is capable to automate several tests which include routine checks, accuracy test, linearity test, reproducibility test, repeatability test, concordance MBq/mCi test, and geometry test. In principle, the program computes correction factors that should be applied to minimize the uncertainty of measurements and the determining factors for success or failure of each test, then visualizes the results as tables and curves into a pdf file. Therefore, this interface can be considered as an efficient tool for performing quality control tests of dose calibrators thought it is still unable to offer the correction factors for the geometry test without experiment which will be achieved by integrating Monte Carlo simulation into the GUI.

In environment radiation measurement, calculation the correction factors are critical, especially for low energy measurement because of self-absorption phenomena. In this work the main purpose is to determination the self-absorption correction factors of lead-210 (210Pb) energy (46.5keV) in various environment samples (7 sediments, 5 soil) using an experimental method called Spike Method. The samples were collecting from different places in Syrian. They were prepared according to the laboratory producers starting from collecting, cleaning, drying, grounding, hemogenic and calculating the appearance density. Low-energy gamma spectroscopy HPGe was used for radiation analysis which available at the laboratories of the Protection and Safety Department - Syrian Atomic Energy Commission – Syria. The spike method depends on adding a quantity of a standard solution with a known activity which contains lead isotope 210Pb and added to the studied samples. Self-absorption correction factors (CF) calculated by the ratio of the count rate or activity of spiked and unspiked samples. The CF for sediment samples were between 29% to 54% and for soil samples, the CFs were between 38% to 56% recording correction higher than sediment samples. The results showed a relatively high self-absorption and CFs values because of the chemical composition changeable between the spiked and unspiked samples. For that, it is better to adopt other methods less expensive, give results faster, higher accuracy and do not make change in the chemical composition. The results were also showed the density factor is the most influential factor in self-absorption phenomena.

On the level of this article, we deal with nuclear radiation (and their residues), which is defined as a physical phenomenon and strong atomic activity that occurs in unstable atoms of elements. We are interested in studying radiation as the emission or diffusion of energy into space in the form of electromagnetic waves or particles. The scientist Fermi (1934 AD) is among the first to present scientific research in this field. Radioisotopes are considered one of the most prominent discoveries of modern science and based on the importance of the topic, scientists and researchers searched for methods and techniques to facilitate the implementation of practical applications for radiation measurement, and among those methods a specialized program was used to simulate radiation dose (digital simulation in a computer through the use of an imaginary model of the radiometric process with technology Monte Carlo using code (Geant 4). We have also highlighted the views of researchers and specialists in the area of disposal of radioactive waste, relying on a field study and a comparison of some of the currently adopted techniques to get rid of the negative consequences that each unreasonable (reckless) management and measure of this radioactive waste may have Among the most prominent results we have reached is highlighting the weakness of dealing with this topic and not giving it the right to research and scientific achievements carried out by researchers, which increases the complexity of the situation and from which it is difficult to control the problem in the future.