Sources Of Ionizing Radiation Research Articles

Exploring the viability of desiccant silica gel beads as A novel material for radiation dosimetry: A preliminary investigation

Silica gel bead material, with its porous structure, high surface area, uniform particle size, stability, and excellent adsorption capacity, is a key material for advancing dosimeter technologies. These qualities make it ideal for accurately measuring and monitoring ionizing radiation in various environments. The research aims to characterize the response of different ionizing radiation sources on desiccant silica gel beads, laying the groundwork for potential applications in medical dosimetry. In this study, silica gel bead samples were subjected to various radiation sources, including gamma rays with an average energy of 1.25 MeV, photons (6 MV), and electrons (6 MeV). The radiation was administered at doses within the range of 2 Gy–20 Gy, which is commonly used in radiotherapy to evaluate the dosimetric behaviour of the desiccant silica gel bead samples using the conventional thermoluminescence (TL) technique. The silica gel bead samples have been found to provide a highly linear dose response within the dose range of interest, with the coefficient of determination (R2) ranging between 0.91 and 0.96. Additionally, the samples show high sensitivity at lower doses and maintain excellent reproducibility, with a standard deviation of less than 4%. In regard to fading evaluation, desiccant silica gel beads exhibit minimal signal loss within 35 days post-irradiation, averaging between 20% and 38%. The findings of this study are promising for developing a new dosimeter, which will enhance radiation monitoring and measurement practices in various environments. These improvements cover dosimetric applications in medical and industrial fields including food safety and agricultural development.

Collective Effective Dose from Medical Radiation Use in Indonesia: Si-INTAN Data Study Period 2018-2021

Until now, there has been no information regarding the value of the collective dose per procedure using the X-ray modality in Indonesia. As in the ICRP 103 publication (2007), it is stated that the collective effective dose is an instrument for optimizing protection by comparing radiological technology and the protection procedures that will be taken. This article aims to raise awareness and optimize the use of diagnostic X-ray modalities by providing an estimate of the proportion of Indonesia's total population compared to the number of radiation examinations carried out, the collective annual effective dose, and the potential risks. The information provided is based on a data reported to the Patient Dose Data Information System (Si-INTAN) application from 2018 to 2021. The data is in the form of the number of patient examinations per modality and the national Diagnostic Reference Level (DRL) value for each type of procedure. From the results of the analysis, it was found that the proportion of patient examinations per modality in the sequence was conventional radiology (79.19%), CT Scan (17.56%), dental radiology (1.75%), interventional fluoroscopy (0.70%), medical diagnostic nuclear (0.62%), and mammography (0.18%). The majority of the annual collective effective dose in Indonesia comes from CT Scan (97.45%), interventional fluoroscopy (1.30%), conventional radiology (0.86%), diagnostic nuclear medicine (0.38%), and a small percentage from mammography and dental radiology. It is estimated that around 116.6 million Indonesians receive radiation exposure for medical needs with a collective annual effective dose of 860,000 man-Sv. This collective effective dose provides an estimate of the incidence of cancer in the Indonesian population of around 0.016% of the entire population in 2021. This information can be used as a baseline to evaluate trends in using and monitoring ionizing radiation sources for medical imaging needs in Indonesia. Keywords: effective dose, collective effective dose, diagnostic reference level (DRL), radiation imaging, diagnostic X-rays, radiation protection

Specificity of DNA damage formation induced by femtosecond near-infrared laser filamentation in water

We investigated the deoxyribonucleic acid (DNA) damage induced by laser filamentation, which was generated by focusing femtosecond near-infrared Ti:Sapphire laser light in water at several repetition rates ranging from 1000 Hz to 10 Hz. Using plasmid DNA (pUC19), the single-strand break, double-strand break, nucleobase lesions, and the fragmented DNA were analyzed and quantified by agarose gel electrophoresis. Additionally, the H2O2 concentration after irradiation was determined. We observed that (1) the DNA damage per laser shot and (2) the enzyme-sensitive base lesions per total DNA damage decreased as the laser repetition rate increased. Furthermore, (3) extraordinarily short DNA fragments were likely to be produced, compared with those produced using X-rays, and (4) most OH radicals could be eliminated by recombination to generate H2O2, preventing them from damaging the DNA. The Monte-Carlo simulation of the strand break formation implies that the observed dependency of strand break efficiency on the laser repetition rate is mainly due to diffusion of DNA molecules. These findings quantitatively and qualitatively revealed that an intense laser pulse induces a specific DNA damage profile that is not induced by X-rays, a sparsely ionizing radiation source.

PRACTICAL RECOMMENDATION FOR CALIBRATION OF RADIATION SOURCES USED FOR CONTACT RADIOTHERAPY

Relevance: This paper presents two methods for calibrating ionizing radiation sources in brachytherapy. The first method involves measuring the radiation activity using a well chamber, while the second method involves measuring the air kerma using an ionization chamber. Additionally, the application and measurement method of radiochromic film is demonstrated. The relevance of the above calibration methods of the ionizing radiation source in brachytherapy is explained by the need to ensure high accuracy and reliability of treatment. All calibration methods provide a multilevel approach to quality control and safety of brachytherapy. Combining an ionization chamber, air kerma power measurement, and radiochromic film allows for high dosimetry accuracy, which is critical for successfully treating patients and minimizing side effects. The study aimed to analyze primary calibration methods and their applicability in medical institutions. Methods: The data from the radiation source provided by the manufacturer is compared with the measurements obtained using the method proposed in the article. Radiochromic film was exposed to radiation to assess the initial dose distribution in the phantom. This scientific research was carried out within the framework of the PCF scientific program “Metrological support of dosimetric measurements in contact radiation therapy,” IRN BR12967832. Results: It has been established that the measurement accuracy is approximately 1.2% at a 95% confidence interval. The activity of the radiation source and the field distribution around it were measured using methods recommended by the IAEA. Conclusion: In our case, the difference between the data measured by these two methods is 1.2%. Using the third method, which involves radiochromic film, it has been established that the radiation source distribution matches the treatment plan. The user has the right to choose any of the calibration methods mentioned above for the eye, taking into account the technical capabilities of their medical facility.

Simulation of Radiation-Induced DNA Damage and Protection by Histones Using the Code RITRACKS.

(1) Background: DNA damage is of great importance in the understanding of the effects of ionizing radiation. Various types of DNA damage can result from exposure to ionizing radiation, with clustered types considered the most important for radiobiological effects. (2) Methods: The code RITRACKS (Relativistic Ion Tracks), a program that simulates stochastic radiation track structures, was used to simulate DNA damage by photons and ions spanning a broad range of linear energy transfer (LET) values. To perform these simulations, the transport code was modified to include cross sections for the interactions of ions or electrons with DNA and amino acids for ionizations, dissociative electron attachment, and elastic collisions. The radiochemistry simulations were performed using a step-by-step algorithm that follows the evolution of all particles in time, including reactions between radicals and DNA structures and amino acids. Furthermore, detailed DNA damage events, such as base pair positions, DNA fragment lengths, and fragment yields, were recorded. (3) Results: We report simulation results using photons and the ions 1H+, 4He2+, 12C6+, 16O8+, and 56Fe26+ at various energies, covering LET values from 0.3 to 164 keV/µm, and performed a comparison with other codes and experimental results. The results show evidence of DNA protection from damage at its points of contacts with histone proteins. (4) Conclusions: RITRACKS can provide a framework for studying DNA damage from a variety of ionizing radiation sources with detailed representations of DNA at the atomic scale, DNA-associated proteins, and resulting DNA damage events and statistics, enabling a broader range of future comparisons with experiments such as those based on DNA sequencing.

Advanced Technology for Energy, Plant Nutrients and Water Recovery at Wastewater Treatment Plants

In present times, with increasing emphasis on circular economies, municipal wastewater treatment plants (WWTPs) are considered resource recovery facilities. The targeted resources are water, biogas, and sludge, organic residuals containing nutrients and elements needed by plants (nitrogen and phosphorus). Sludge is a byproduct that constitutes the largest volume of all other byproducts obtained in wastewater treatment plants. Its processing and disposal are challenging for environmental engineers because of its complexity. Thus, quick development and implementation in industrial practice of sludge valorization and utilization technologies is required, where high nutrient content must be taken into account. Also, the occurrence of a variety of pathogens in sewage sludge is a matter of concern, even in the case of developed countries. The use of untreated sludge or wastewater in agricultural activities poses a serious risk of bacterial and parasitic infection in human beings. To overcome such issues, the application of ionizing radiation processing, especially electron beam (EB), can be considered a promising method. Its effectiveness in pathogen removal has been proven by researchers. Water radiolysis products created during irradiation of water are highly reactive and cause some effects such as DNA damage, OH • radical production, etc. Additionally, ionizing radiation technologies in sewage sludge treatment enhance the efficiency of the methane fermentation process. Depending on specific needs, different types of ionizing radiation sources can be discussed. Based on the review information and our research results, the basic engineering parameters of hybrid installation have been presented as the conclusion of the report. In this technical solution, a notably effective additional step would be the use of EB irradiation, combined with conventional wastewater treatment, to achieve efficient removal of pollutants.

Biological Efficacy of Ionizing Radiation Sources on 3D Organotypic Tissue Slices Assessed by Fluorescence Microscopy.

Traditional cell-based radiobiological methods are inadequate for assessing the toxicity of ionizing radiation exposure in relation to the microstructure of the extracellular matrix. Organotypic tissue slices preserve the spatial organization observed in vivo, making the tissue easily accessible for visualization and staining. This study aims to explore the use of fluorescence microscopy of physiologically compatible 3D tissue cultures to assess the effects of ionizing radiation. Organotypic tissue slices were obtained by vibratome, and their mechanical properties were studied. Slices were exposed by two ionizing radiation sources; electron beams (80 Gy and 4 Gy), and soft gamma irradiation (80 Gy and 4 Gy). Two tissue culture protocols were used: the standard (37°C), and hypothermic (30°C) conditions. A qualitative analysis of cell viability in organotypic tissue slices was performed using fluorescent dyes and standard laser confocal microscopy. Biological dosimetry is represented by differentially stained 200-µm thick organotypic tissue sections related to living and dead cells and cell metabolic activity. Our results underscore the ability of fluorescence laser scanning confocal microscopy to rapidly assess the radiobiological effects of ionizing radiation in vitro on 3D organotypic tissue slices.

Clinical guidelines for prevention, diagnostics, treatment and recovery from acute radiation injuries: classification and basic pathology

The provision of state guarantees to citizens with medical care is achieved by compliance with clinical recommendations by medical organizations. However, acute diseases (conditions) caused by excess radiation were excluded from the relevant pathologies for the development of appropriate clinical recommendations. The current events increase the relevance of acute radiation pathology for the healthcare system and determine the high risk of such cases among the personnel of radiation-hazardous facilities and population. The necessity of developing national clinical guidelines for the prevention, diagnosis, treatment, and rehabilitation of acute radiation injury victims is substantiated. Based on an analytical review of the databases of NEB, PubMed, and Medline for 1970 to 2023 on the problem of prevention, diagnosis, treatment, and rehabilitation of individuals exposed to excess radiation and analysis of the regulatory framework governing the process of creating clinical recommendations in the Russian Federation on the provision of medical care to victims of acute radiation injuries, the main terms and their definitions relevant to acute radiation pathology were formulated, which must be unified when developing clinical recommendations. The basic classification of acute radiation lesions is presented, systematizing the variety of possible clinical forms of diseases (conditions) and their etiopathogenetic variants based on the characteristics of the types of ionizing radiation sources and individual characteristics of the conditions of acute radiation exposure. Variants of working clinical classifications of acute radiation lesions based on the generalization of the experience in the country and the world on the systematization of acute radiation pathology were determined. In general, the expediency of developing a group of clinical recommendations for the prevention, diagnosis, treatment, and rehabilitation of acute radiation injuries, covering all the various current clinical forms of diseases caused by excess (uncontrolled, unregulated, emergency) exposure, is justified. The task of determining the current list of diseases (conditions) and groups of diseases (conditions) caused by excessive human exposure in the dose range that can lead to the development of acute radiation lesions is of practical importance both for departmental medicine and the country’s healthcare system.

Развитие правовой базы в области обеспечения радиационной безопасности

Purpose: To justify the main areas of Russian legacy framework in the field of radiation safety assurance as a basis for improvement of the current standards and regulations. Material and methods: The article analyses international documents and Russian federal laws regulating different aspects of human safety and highlights the most important approaches and procedures of safety assurance proven in practice. Results: The necessity of developing new federal law “On Radiation Safety in Russian Federation” is substantiated. The article shows that internationally recognized principles of radiation safety assurance should be applied in Russia: those are the preservation principle, the responsibility principle, the continuous control principle and, in particular, the permission principle. The last principle means that what is not permitted is forbidden when it comes to handling ionizing radiation sources. The article describes the main provisions and elements of new law and details some considerations that need to be articulated and enhanced in new federal law based on positive experience of their implementation in the current federal laws on different safety aspects. Conclusion: New federal Law “On Radiation Safety in Russian Federation” should incorporate all positive experience of applying the current Federal Law of 09.01.1996 N 3-FL “On Radiation Safety of the Public” and other Russian laws regulating different aspects of human safety assurance in various fields. New law should be based on unconditional priority of protection of human life and health, present and future generations and the environment from possible radiation exposure. New law should enable interaction of the facilities whose activities are related to handling ionizing radiation sources and facilities of the infrastructure for radiation safety assurance, as well as provide connection to other regulations that set specific norms and requirements in the field of radiation safety assurance.

Extended study of the influence of europium doping on phosphate glass

The phosphate glasses with various Eu2O3 concentrations (0.1–3.0 w/w%) were synthesized and studied regarding the influence of europium dopant on the properties of irradiated phosphate glasses. During studies, samples were irradiated using two types of ionizing radiation sources (β− and γ), with obtained doses up to 40 kGy. TL studies were investigated using various methods, such as TL response vs. radiation dose and the TMax-Tstop method. To further investigate, if increasing the europium concentration affects the structure of electron traps, Computer Glow Curve Deconvolution studies linked with various heating rates methods were applied –increasing the concentration of dopant does not influence the number and energy of electron traps in irradiated samples. This fact was also supported by the results of the thermoluminescence spectrum – where no additional signals, besides wide signals from native glass were observed. OSL and IRSL studies were also conducted, for OSL we observed quenching of the signals, similar as in the TLD case. For IRSL studies all samples didn't display any signals. Finally, to understand if Eu3+ also has a “protective” effect, decreasing the yield of generating F-centers during irradiation, UV-VIS spectroscopy was used. It was established that samples doped with europium oxide possess ca. 20% lower signals at F-center maximum (at 475 nm), the building-up maximum at 320 nm was observed, characteristic of the absorption band of Eu2+. All data indicate that europium in phosphate glass is taking the role of an efficient electron quencher. This quenching phenomenon occurs in three ways: first (direct) when the ion reduction process (Eu3+→Eu2+) competes with the formation of F-centers, and second (indirect) when during heating electrons coming from F-centers were quenched by near Eu3+ ions. The third mechanism of quenching occurs through the electron's non-radiative transition induced by increased stress in the glass matrix caused by a large ionic radius of the dopant.

The Molecular Mechanisms in Senescent Cells Induced by Natural Aging and Ionizing Radiation.

This review discusses the relationship between cellular senescence and radiation exposure. Given the wide range of ionizing radiation sources encountered by people in professional and medical spheres, as well as the influence of natural background radiation, the question of the effect of radiation on biological processes, particularly on aging processes, remains highly relevant. The parallel relationship between natural and radiation-induced cellular senescence reveals the common aspects underlying these processes. Based on recent scientific data, the key points of the effects of ionizing radiation on cellular processes associated with aging, such as genome instability, mitochondrial dysfunction, altered expression of miRNAs, epigenetic profile, and manifestation of the senescence-associated secretory phenotype (SASP), are discussed. Unraveling the molecular mechanisms of cellular senescence can make a valuable contribution to the understanding of the molecular genetic basis of age-associated diseases in the context of environmental exposure.

POPULATION'S RADIATION ANXIETY STRUCTURE ANALYSIS FOR THE PRE-COVID-19 PERIOD

Introduction. A considerable amount of conflicting reports creates conditions for concern about the effects of radiation on health. The adequacy of the assessment of problems and responses to these challenges depends on the sources used by a person, his culture and education level, as well as the emotional overtone of this assessment.
 The aim of the study is to determine dynamic changes in the prevalence and structure of population’s radiation anxiety states under stable social conditions based on a psychological and hygienic assessment.
 Materials and methods: In order to research and assess the perception of Kropyvnytskyi residents about the degree and prevalence of radiation anxiety states, a survey was conducted on Facebook and Instagram social networks from February to December 2019 using Google Form. For assessment of dynamic changes in radiation anxiety, data from our own studies in 2014 were used [9]. The questionnaire methodology was based on the principles of the previously tested and patented "Methodology for determining radiation anxiety among the population" and the monograph "Radiation anxiety among the population". Three hundred and twenty four residents of Kropyvnytskyi aged 18 to 73 were included in the study, 155 (47.8%) men and 169 (52.2%) women. The average age of the interviewees (Me (LQ; HQ)) was 27 (20; 33) years old.
 Results. A specific psycho-emotional state is developed and maintained at some level in the residents of cities with nuclear power plants – radiation anxiety, which is manifested by a complex of neuropsychological and somato-physiological disorders against the fear of ionizing radiation sources background. At the same time, such a psychogenic effect may not be related to the degree of actual effects of ionizing radiation on human health. It was determined that in 2019, before the COVID-19 pandemic and Russia's full armed aggression against Ukraine, more than 90% of the surveyed residents of Kropyvnytskyi, regardless of gender and age, were concerned about potential radiation pollution of the environment and foodstuffs, medium level of radiation anxiety was in 34,9%, and high level in 14.8% . Low radiation anxiety was detected in 41.4% of respondents, and in 8.9% it was absent.
 Conclusions. Over 5 years (from 2014 to 2019), there were noticeable negative changes in the structure of the radiation anxiety states among the surveyed urban residents, namely: the amount of people without signs of radiation anxiety halved (8.9% vs. 16.0%) and respondents with the high level of this psycho-emotional state increased almost four times (14.8% versus 3.9%). The obtained results encourage the authors to future studies of specific radiation anxiety states among the population to clarify their dynamics.

USE OF CONTROL CHARTS OF CUMULATIVE AMOUNTS FOR THE METHOD OF EXTENDING THE SERVICE LIFE OF THE IONIZING RADIATION SOURCE ACCORDING TO CALIBRATION RESULTS

The article forms and substantiates the application of control charts for the method of extending the service life of the source of ionizing radiation (SIR). An algorithm for its aim was developed. The main types of con- trol charts and the features of their application were considered. A methodology for constructing a cusum map for extending the service life of SIRs based on the results of their calibrations, as well as a methodology for checking the results of SIR calibration for statistical controllability, were developed. Extrapolation methods were considered, and the method of least squares was chosen as the most optimal for this technique.

The effect of external radiation exposure per person depending on his position and anthropometric indicators

This study reviews existing methods for modelling the impact of ionising radiation sources on the human body. Using advanced modelling methods, the main modelling parameters are determined and it is revealed whether anthropometry affects the increase or decrease of the total radiation dose in the conditions of work in radiation-contaminated areas of the nuclear fuel cycle. The most rational and safe approach today is to conduct experimental studies on anthropomorphic mannequins to simulate human exposure using the RANDO phantom model with different geometries of exposure to ionising radiation sources. The considered modelling methods are taken from medicine, nuclear power, economics and labour protection, where they have found their application and continue to be improved. For further research, it is necessary to use other types of models, such as the Event Tree model, SWOT analysis model, Zero Risk model, Correlation and Regression System model, Matrix model, and other computer models and simulations using artificial intelligence. The factors proposed in this article provide a “complete picture” of the factors that occur in real conditions of research, measurements, service, security and physical protection of radiation-hazardous facilities such as tailing ponds of former uranium production.

Physical and radiation shielding properties for borate, boro-tellurite, and tellurite glass system modified with different modifiers: Comparative study

Two newly synthesized glass series, 10Bi2O3-20BaO-(70-x)B2O3-xTeO2, and 10MoO3-20SrO-(70-x)B2O3-xTeO2, where x = 0, 35, and 70 mol%, were fabricated using the melt-quenching technique. The fabricated glass samples' physical properties and radiation shielding capabilities were examined. The insertion of TeO2 into the glass composition increased the density values, with the glass samples labeled BBB-T70 (6.53 g/cm3) and SBM-T70 (5.66 g/cm3) exhibiting the highest density due to the increased concentration of TeO2. The addition of TeO2 led to loosely bonded glasses, indicating lower glass stability. Using SRIM and Phy-X/PSD software, the radiation shielding capabilities of the produced samples were investigated for various radiation types, including alpha particles, protons, neutrons, and gamma rays. The increase in TeO2 content and the reduction in B2O3 revealed significant increases in the linear attenuation coefficient (LAC) values and improved gamma shielding properties. For example, the LAC values at 0.283 MeV are 0.283, 0.367, 0.667, 0.902, 1.095, 1.313, and 1.55315 cm−1 for SBM-T00, SBM-T35, SBM-T70, BBB-T00, BBB-T53, and BBB-T70, respectively. However, the SBM-T00 sample exhibited lower charged particle shielding properties. The SBT-T35 and BBB-T00 samples showed the highest ability to stop fast neutrons. In conclusion, the glass samples synthesized in this work are highly recommended for shielding against various ionizing radiation sources.

Radiation Protection of a 3D Computer Tomography Scanning Workplace for Logs-A Case Study.

Despite its undeniable advantages, the operation of a CT scanner also carries risks to human health. The CT scanner is a source of ionizing radiation, which also affects people in its surroundings. The aim of this paper is to quantify the radiation exposure of workers at a 3D CT wood scanning workplace and to determine a monitoring program based on measurements of ionizing radiation levels during the operation of a CT log scanner. The workplace is located in the Biotechnology Park of the National Forestry Centre. The ionizing radiation source is located in a protective cabin as a MICROTEC 3D CT machine with an X-ray lamp as X-ray source. The CT scanner is part of the 3D CT scanning line and its function is continuous quality scanning or detection of internal defects of the examined wood. The measurement of leakage radiation during scanning is performed with a metrologically verified meter. The measured quantity is the ambient dose equivalent rate H˙*10. The results of the measurements at the selected measurement sites have shown that, after installation of additional safety barriers, the CT scanner for the logs complies with the most strict criteria in terms of radiation protection. Workers present at the workplace during the operation of the CT scanner are not exposed to radiation higher than the background radiation level.

Preparation of pollucite ceramic matrices as 137Cs ionizing radiation source by spark plasma sintering

The paper proposes an original one-stage method using spark plasma sintering technology (SPS) of manufacturing the ionizing radiation source (IRS) of closed type with a non-dispersible ceramic core based on pollucite obtained using aluminosilicate raw materials saturated (24.3 wt%) with cesium, and doped with 10–40 wt% CsCl. According to the XRD, EDX, AAS and DTA-TG data, optimal conditions for hydrothermal synthesis zeolite NaA were established, the consolidation kinetics and phase transformations into ceramic pollucite under SPS conditions were studied. The ceramics had a relative density of 99.8 % and mechanical strength up to 732 MPa, a low rate of cesium leaching 10−7 g/cm2 day and thermal resistance in air up to 1000 °C. It was confirmed by SEM and EDX that the destruction and deformation of pollucite ceramics in the composition with CsCl and steel at the boundary of their contact in the design of the IRS product was absent and diffusion of cesium outside the ceramics did not occur. The achieved cesium content in the ceramic core of the resulting the ionizing radiation source, which meets high quality and regulatory requirements, is 44.3 wt%. The results of the study may be promising for the manufacture of industrial products.

APLIKASI PENGELOLAAN LIMBAH RADIOAKTIF BERBASIS ANDROID DI KEDOKTERAN NUKLIR RSUP DR. KARIADI

The utilization of ionizing radiation sources for diagnostics and therapy, such as radioactive substances, including radionuclides and radiopharmaceuticals, generates radioactive waste. This radioactive waste poses potential radiation hazards for workers, members of the public, and the environment. Therefore, it is crucial to manage it correctly by established regulations. Radioactive waste resulting from the utilization of Nuclear Medicine varies in terms of activity value and mass, necessitating different storage times and appropriate management. Considering these factors, this study aims to develop an Android-based application called 'Si Mbah KeCE Kariadi' (Kalkulasi Limbah Kedokteran-Nuklir Cepat dan Efektif di RSUP Dr. Kariadi) for the management of low and medium-level open radioactive waste in Nuclear Medicine. This application aims to estimate when radioactive waste can be released before being discharged to the hospital's sanitation department. The research method employed in this study involves applying the principles of radioactive waste management, specifically the decay of activity. The radioactive waste release calculator application is generated by utilizing the radioactive decay equation derived from measuring the initial radioactive waste radiation exposure rate using a survey meter radiation measuring instrument and referencing the clearance level value to estimate the release time of the radioactive waste. The evaluation of this application indicates that the radiation exposure value of the radioactive waste is equivalent to the background radiation level at its release, suggesting that it can be disposed of in the hospital sanitation department for further management as infectious waste from patients. Keywords: radioactive waste management, activity decay, application of android, nuclear medicine, clearance level.

BEST PRACTICE PERAN TIM PETUGAS PROTEKSI RADIASI (PPR) DALAM IMPLEMENTASI KESELAMATAN RADIASI DI MANDAYA ROYAL HOSPITAL PURI

Utilizing ionizing radiation sources at Mandaya Royal Hospital Puri requires strict implementation of radiation protection measures. The principles of radiation protection must be applied meticulously, considering the potential effects. The hospital has a team of radiation protection officers (RPO) comprising radiographers and medical physicists responsible for ensuring radiation safety and implementing radiation protection measures. The RPO team has conducted various radiation protection activities between January and July 2023, including monitoring radiation worker doses, optimizing patient radiation doses, conducting internal and external quality control, checking radiation protection equipment, monitoring supporting equipment related to radiation safety, socializing radiation protection across all hospital departments, and testing room radiation exposure. The RPO team has been executing their 2023 program, adhering to the best practices. The hospital management plays a crucial role in carrying out radiation protection activities, and their support and commitment are vital to the practical and sustainable implementation of the RPO team's activities. Keywords: Radiation protection officers (RPO), radiation safety culture, radiation dose, radiation protection.

Experimental study of dosimetric properties of thermoluminescent powder TLD-100

The creation of a scientifically substantiated quality assurance system for dosimetry and the optimization of medical exposure of the population of Ukraine during diagnostic and therapeutic procedures (and the possibility of dosimetric control and monitoring of emergency situations) falls within the field of the application of ionizing radiation sources (IRs). Trends in modern medicine in most countries, including Ukraine, prove a continued increase in the share of medical exposure. The main requirements and recommendations for the use of IRs for medical purposes while ensuring the radiation safety requirements for patients are provided in the documents of such International Organizations as the International Commission on Radiological Protection (ICRP), the International Atomic Energy Agency (IAEA), the World Health Organization (WHO) and the European Commission (EC).
 One of the key factors to ensure the quality of radiation therapy is metrological and dosimetric support. To enhance the effectiveness of radiation treatment and reduce the number of complications in the future, it is necessary to irradiate the local target within the patient’s body with a dose error of no more than 5%. Control of the radiation output of the therapeutic device, i.e., the calibration of the therapeutic beam used in the treatment process, is an essential element of radiation therapy.
 Radiation protection programmes are based on checking the accuracy of the calibration of remote radiotherapy devices using thermoluminescent dosimeters (TLDs) – small plastic capsules filled with thermoluminescent powder that are sent by post to radiology centres for exposure to a specific dose in a water phantom.
 Radiation therapy in Ukraine is primarily conducted using cobalt machines, X-ray therapy devices and linear accelerators.
 The results of the study include the examination of the dependency of measurement results on various exposure parameters using the automatic reader PCL-3, the determination of dosimetric characteristics of the thermoluminescent powder TLD-100, and the development of a calibration method for thermoluminescent dosimeters under standard irradiation conditions on a remote gamma therapy device.
 Therefore, the accuracy of beam calibration using TLD dosimeters has been studied, which will enable to timely detect errors in clinical dosimetry and reduce the number of cases of radiation-related complications for patients during their treatment.