Radiation Protection Of Personnel Research Articles

A COMPUTER PROGRAM FOR THE DETERMINATION OF ABSOLUTE ACTIVITIES IN CONTAMINATIONS AND SKIN DOSES.

At radiological facilities, protocols are in place to guide radiation protection personnel in the event of the radioactive contamination of surfaces. A count rate measurement is performed with a portable contamination survey meter and a sample of the contamination is taken for later analysis and identification of the radionuclides. If the contaminated surface was of a worker's skin, then a skin dose assessment is made. The determination of the absolute activity of the radionuclides of the contamination often rests on the assumed detection efficiency of the survey meter used in the initial counting. This may lead to important underestimation or overestimation of the radionuclides' activities as the detection efficiency of the instrument must depend on the radiation type, the energy and the backscatter characteristics of the surface. This paper reports on a user-friendly computer application that relies on databases of pre-calculated detection efficiencies and skin dose rate conversion factors for the accurate assessment of contamination activities and skin doses. The results of some cases are compared with the available data in the literature.

Тривимірне моделювання як інструмент підвищення культури безпеки під час проведення робіт на радіаційно-ядерних об’єктах

As work is planned at the Shelter object (SO), minimizing doses to the personnel involved in these work is of great importance. This is of particular importance for the construction work with the dismantling of the structure, which is characterized by large collective effective doses, which are taken by the personnel during the hour of its implementation. The need to assign personnel doses, as well as optimize approaches to the radiation protection and, first of all, biological protection, is related to this already at the design stage. As the radiation situation will change during the dismantling of unstable structures, design solutions must take into account possible changes in the radiation dose when planning protective measures. To determine the intensity of the gamma radiation dose, a method of mathematical modeling based on the “point kernel” model is proposed. This approach makes it possible to carry out calculation and analysis of the radiation situation practically in real time. By means of the ChNPP VRdose Planner Pro program, a three-dimensional model of the SO roof outer shell with selected sources of gamma radiation and building structures with the protective screens properties was built. The radiation situation analysis was made and a radiation field visual display above the roof was shown. Models of building structures were created, which to some extent shield gamma radiation emanating from the SO Central Hall. Three-dimensional modeling of the early dismantled building structures was carried out using the program ChNPP VRdose Planner Pro v. 2.2.2. The application of methods of modeling radiation conditions during planning and execution of work in radiation-hazardous conditions will make it possible optimizing design solutions regarding the dismantling of unstable structures of the Shelter object, as well as optimizing the structure of radiation protection of personnel. The software package is a convenient tool for performing calculations of estimated exposure doses in radiation-hazardous conditions, enables quick and visual modeling of alternative work execution options, and enables optimization of the work performance process and personnel behavior in radiation-hazardous conditions. Based on the simulation, it is possible to create an interactive software package on the Chornobyl nuclear power plant training center for detailed personnel education and training. The results of the radiation situation analysis can be used in the performance of work planning in radiation-hazardous conditions to ensure the personnel protection in accordance with the ALARA principle.

A simulation system of radiation field and its detection for nuclear and radiological emergency preparedness and response training

Appropriate training of the related personnel is one of the most important aspects in nuclear and radiological emergency preparedness and response. The use of simulation training could provide the trainees learning experience of a lifelike, hands-on scenario without associated radiation safety restrictions. In this study, we established a radiation field simulation system that includes two separate parts. For small-area radiation field simulation, a set of simulation sources and detectors was designed based on ultra wide band distance measurement technology. For large-area field simulation, a Gaussian plume model was used to simulate the dispersion of released radioactive aerosols and calculate the consequent radiation field. Also, a Global Position System positioning and wireless transmission technique was used for simulation instruments’ data acquisition. This system could create a verisimilar but also safe and radiation-free environment and can be used in the training of nuclear emergency first responders, rescue teams or radiation protection personnel.

Study on Compliance with Radiation Protection Rules in the Medical Imaging Department of Pr Bocar Sidy Sall Hospital of Kati (Mali)

Objective: Evaluate the level of compliance with radiation protection rules in the medical imaging department of the University Hospital Center (CHU) of Kati. Methodology: This was a cross-sectional and descriptive study carried out in the medical imaging department of Pr Bocar Sidy Sall (BSS) Hospital of Kati. A questionnaire was developed and sent to the staff of the medical imaging department. The assessment focused on the radiation protection of personnel, radiation protection measures for patients, the delimitation and signage of zoning as well as the application of radiation protection principles. Results: Twenty-one people participated in the study, 90% of whom were men. The 30 - 39 age group was predominant with 61.90%. 33.33% of the staff knew the principles of radiation protection; 86% of our sample knew the basic rules of radiation protection. The majority of the staff in the imaging department (61.90%) had a perfect knowledge of protective equipment. For 76% of our workforce, the limits of the radiation doses received are regulated in Mali. 76% of those surveyed have not taken any additional training in radiation protection. The doors are closed during the X-ray examination for 76.19% of the respondents and 95% of the staff put themselves behind the sealed screen during the examination. For 81% of the respondents, the design of the premises met radiation protection standards. 62% of practitioners have a dosimeter and 80% of them wear it during their shift. For 62% of our sample, the change of the dosimeter is quarterly. The systematic request for DDR (date of last menstrual period) in women and the adaptation of the delivered dose to the patient’s morphology was only carried out by 65% of practitioners. The majority of staff (81%) did not benefit from medical surveillance, while for 55% of respondents the level of radiation protection in the establishment was average. Conclusion: This study enabled us to highlight the shortcomings in terms of radiation protection within the imaging department of the CHU Kati.

On the formation of the first Soviet industrial service of dosimetric control at the Ural nuclear plants (1945–1960)

The subject of this research is the process of organizing dosimetric service on the example of the Ural nuclear complex, primarily, the most powerful plutonium plant, the pioneer of the domestic nuclear industry – “Mayak” chemical plant in the 1945 – 1960. In the course of development of complex and hazardous for people and nature nuclear technologies, the problems of radiation protection of personnel at the first nuclear facilities became urgent, as most employees have been exposed to radiation. This required a set of emergency measures to create of safe working conditions and organize dosimetric control of nuclear energy workers. Based on the declassified archival documents, a substantial part of which is being introduced into the scientific discourse for the first time, as well as the reminiscences of the Soviet nuclear project participants, the article describes the peculiarities of formation of the first domestic service of industrial dosimetry, and provides periodization of this process. This defines the scientific novelty of the research. The use of historical and genetic method allowed outlining the prerequisites for the creation of the service of dosimetric control of the nuclear energy workers, its conditionality by the specificity of implementation of the Soviet uranium project, and a range of attendant problems. The method of historical periodization determined the key stages in organizing the dosimetric service in the context of establishment of the nuclear industrial complex. The historical-retrospective method allowed assessing the results of the activity of the scholars, leadership of the chemical plant “Mayak”, experts of dosimetric service aimed at solution of the issues related to radiation protection from the standpoint of time distance. The conclusion is made that the first domestic dosimetric service formed during the difficult period of the development of plutonium production in the Ural Region and committed work of its employees considerably contributed to ensuring safety of working conditions and preserving health and lives of thousands of the participants of the crucial for the country nuclear project

Radiation safety analysis of emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor

Objective Radiation safety of emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor is studied, the radiation protection method of emergency repair personnel in the reactor cabin is described, which provides a theoretical reference for personnel radiation protection and emergency repair time control. Methods The radiation was simulated by the Monte Carlo method for emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor, and the radiation was also analyzed with the radiation data measured by experiments in the reactor cabin under the natural circulation condition of the reactor. Results The neutron dose of external irradiation about reactor simulated computation was 140 µSv/h, and gamma radiation dose rate was 48 µSv/h. By experiment and calculation, the effective dose received by emergency repair personnel in the 30-minutein the reactor cabin was 2.2 mSv. Conclusions Under the natural circulation condition of the reactor, the gamma radiation is harmful to emergency repair personnel, but the focus of protection is different locations for maintenance. It’s safe for emergency personnel to repair the reactor in 30 minutes in turn, wearing the respirators. 摘要： 目的 开展对反应堆自然循环工况下抢修人员辐射安全研宄, 阐述反应堆舱应急抢修人员辐射防护方法, 为应 急抢修人员辐射防护和抢修时间控制提供理论参考。 方法 针对反应堆自然循环工况下抢修人员辐射情况, 利用蒙 特卡罗方法进行模拟计算, 并结合自然循环工况下反应堆舱实验测量的辐射数据进行验证分析。 结果 反应堆外照 射模拟计算中子剂量率约为 140 µSv/h, γ 辐射剂量率为 48 µSv/h, 实验测量计算抢修人员在 30 min 堆舱内受到的有效 剂量为 2.2 mSv。 结论 自然循环功率下进堆舱抢修, γ 辐射对抢修人员危害大, 但在不同的位置维修, 防护重点又有 不同;佩戴呼吸器, 30 min 轮流抢修的方式, 对抢修人员是安全的。

Get Protected! Recommendations for Staff in IR.

PurposeEvaluation and registration of patient and staff doses are mandatory under the current European legislation, and the occupational dose limits recommended by the ICRP have been adopted by most of the countries in the world.MethodsRelevant documents and guidelines published by international organisations and interventional radiology societies are referred. Any potential reduction of patient and staff doses should be compatible with the clinical outcomes of the procedures.ResultsThe review summarises the most common protective measures and the needed quality control for them, the criteria to select the appropriate protection devices, and how to avoid unnecessary occupational radiation exposures. Moreover, the current and future advancements in personnel radiation protection using medical simulation with virtual and augmented reality, robotics, and artificial intelligence (AI) are commented. A section on the personnel radiation protection in the era of COVID-19 is introduced, showing the expanding role of the interventional radiology during the pandemic.ConclusionThe review is completed with a summary of the main factors to be considered in the selection of the appropriate radiation protection tools and practical advices to improve the protection of the staff.

Delayed gamma fraction determination in the zero power reactor CROCUS

Gamma rays are an inextricable part of a nuclear reactor’s radiation field, and as such require characterization for dose rate estimations required for the radiation protection of personnel, material choices, and the design of nuclear facilities. Most commonplace radiation transport codes used for shielding calculations only included the prompt neutron induced component of the emitted gamma rays. The relative amount of gamma rays that are emitted from delayed processes – the delayed gamma fraction – amount to a significant contribution, e.g. in a typical zero power reactor at steady state is estimated to be roughly a third. Accurate predictions of gamma fields thus require an estimation of the delayed content in order to meaningfully contribute. As a consequence, recent code developments also include delayed gamma sources and require validation data. The CROCUS zero power research reactor at EPFL is part of the NEA IRPhE and has therefore been characterized for benchmark quality experiments. In order to provide the means for delayed gamma validation, a dedicated experimental campaign was conducted in the CROCUS reactor using its newly developed gamma detection capabilities based on scintillators. In this paper we present the experimental determination of the delayed gamma fraction in CROCUS using in-core neutron and gamma detectors in a benchmark reactor configuration. A consistent and flexibly applicable methodology on how to estimate the delayed gamma fraction in zero power reactors has hitherto not existed – we herein present a general experimental setup and analysis technique that can be applied to other facilities. We found that the build-up time of relevant short lived delayed gamma emitters is likely attributed to the activation of the aluminium cladding of the fuel. Using a CeBr3scintillator in the control rod position of the CROCUS core, we determined a delayed gamma fraction of (30.6±0.6)%.

Становление атомной промышленности на Урале в аспекте радиационной безопасности

This study examines the formation of the nuclear industry in the Urals from the perspective of radiation safety, identifies objective and subjective factors that led to problems in the field of radiation protection of nuclear facility personnel in the process of developing nuclear production, an assessment of the level and extent of radiation exposure to operating personnel. The author notes that the creation of the domestic nuclear industry took place in extremely difficult conditions of the post-war period and was fraught with many difficulties, especially at the initial stage of the formation of the nuclear industrial complex. During the years of commissioning and development of the first nuclear facilities, first of all, the industry pioneer the Mayak chemical plant, production personnel had to work under conditions of increased radioactive radiation. The experimental nature of plutonium production in the Urals, the novelty of the problem, the miscalculations and mistakes of designers and scientists, the extremely small amount of knowledge about the effects of radiation on a living organism, the secrecy regime and a number of other reasons led to the emergence of an emergency radiation situation at all main production facilities of the chemical plant, which entailed a significant re-irradiation of nuclear facility personnel. However, at that time, the problems of radiation protection of personnel did not have priority for the country's top political leadership. The main thing was to get plutonium for the first Soviet atomic bomb in the shortest possible time, regardless of the cost.

Исторические аспекты создания и развития основных объектов атомной отрасли страны. Радиационное воздействие на персонал в разные периоды времени

In connection with the 75th anniversary of the nuclear industry, quite large-scale events were planned, including the XI-th Russian scientific conference «Radiation protection and radiation safety in nuclear technologies». At this conference, as well as at a number of other events, it was planned to make a report on the radiation impact on personnel at different times of the creation and development of the main facilities of the country’s nuclear industry.
 A report was prepared, in which first an attempt was made to analyze the radiation impact on the personnel of the main nuclear and radiation-hazardous facilities of the nuclear industry in the historical context, given the past over the years, significant organizational and structural changes and to assess progress in the field of radiation protection of personnel during its 75 years of existence of industry of Russia (USSR).
 Recent events have made certain adjustments to the plans for the anniversary events, however, the publication of historical data on personnel exposure to these materials seems relevant.
 This article is a logical continuation of the publication «Evolution of the radiation safety system of the country’s nuclear industry and its current state» [1], which provided information about the formation and transformations that have occurred in the domestic nuclear industry over 70 years, the evolution of the radiation safety system, the current state of radiation safety in the industry, as well as current issues of regulatory and methodological support for radiation control at industry enterprises.
 In this publication, on the eve of the 75th anniversary of the industry, an attempt is made to assess the radiation impact on the personnel of the main nuclear and radiation hazardous facilities of the nuclear industry in different periods of their activity.

Estimation of effective dose using two ICRP criteria, applied to radiation protection of personnel in an unshielded PET cyclotron facility

Neutrons have no charge, but ionize indirectly through secondary particles.Neutron radiation is a source of exposure to ionizing radiation for personnel working withcyclotronsthat produce isotopes forpositron emission tomography (PET) radiopharmaceuticals.During production of isotopes in cyclotron in nuclear reactions beside gamma radiation are created also neutrons. The new recommendations of the International Radiological Protection Commission (ICRP) −103 have changed the method of calculating the neutron radiation weighting factor and the tissue weighting factor value that were defined in earlier ICRP recommendations (ICRP, 2007; ICRP, 1991; ICRP, 1996).The aim of this work is to estimate how this change influencesthe calculation of an effective dose in neutron radiation with a complex energy spectrum. This spectrum consists of three regions: a plateau area for thermal neutrons, a peak in the area of fast neutrons with a sharp edge from the high-energy side, and a mild field of decline for intermediate and epithermal neutrons.The application of new recommendations reduces the calculated effective dose by more than 10 mSv. The effect of increasing the effective dose for the maximum fluence area, i.e. energy near 1 MeV,by using a higher value of wR is negligible. The study finds that the new recommendations are less restrictive, and this is of great practical importance becauseno modification to the used shields is required.

Monitoring of Tritium Internal Exposure Doses of Heavy-Water Reactor Workers in Third Qinshan Nuclear Power Plant

To analyze the tritium internal exposure dose of workers in the Third Qinshan Nuclear Power Plant over the past 15 years. Urine samples provided by workers are tested directly to analyze the tritium concentrations and estimate internal exposure dose. Since 2004, an average of approximately 1600 workers have been monitored annually, with an average annual monitoring frequency of approximately 11 000. Since 2004, the average annual collective dose of tritium internal exposure was 149.62 person·mSv, accounting for 19.07% of the total annual collective dose. A total of 18 workers’ annual individual internal tritium radiation doses exceeded 2 mSv, of which 5 workers’ internal tritium radiation doses in a single intake exceeded 2 mSv. The occupational population with the largest total internal tritium radiation doses consists of maintenance personnel, fuel operators, and radiation protection personnel, whose collective doses of internal exposure account for 75.51% of the total collective doses within the plant. Over 15 years of operation, the internal tritium radiation doses of workers in the Third Qinshan Nuclear Power Plant have been strictly controlled within the national regulatory limit and power plant management target, ensuring the health and safety of the workers.

Consolidation of Health Physics Computer Codes: Sustainable Gains in Efficiency, Innovation, and Collaboration.

A decade ago, the nuclear power industry in the United States was on the verge of a nuclear renaissance with the potential to create jobs, funding streams, and great demand for radiation protection personnel. However, based on the high capital investment cost of building and licensing nuclear reactors and declining fossil fuel prices, the renaissance did not reach its full potential. Radiation protection initiatives were developed to bring attention to the profession in order to increase funding for the health physics community during these times of declining resources. It is now essential that the community be innovative in how it uses existing funds and acquires resources. This paper describes a radiation protection computer code program that uses existing resources and international funding to sustain computer codes and tools used in the health physics profession. The program is called the U.S. Nuclear Regulatory Commission's Radiation Protection Computer Code Analysis and Maintenance Program or RAMP. This collaborative, innovative, and transformative model can be followed by others seeking to alleviate the resource issues that exist within the health physics field.

Radiation Transport Calculation of the UGXR Collimators for the Jules Horowitz Reactor (JHR)

Jules Horowitz Reactor (JHR), a major infrastructure of European interest in the fission domain, will be built and operated in the framework of an international cooperation, including the development and qualification of materials and nuclear fuel used in nuclear industry. For this purpose UGXR Collimators, two multi slit gamma and X-ray collimation mechatronic systems, will be installed at the JHR pool and at the Irradiated Components Storage pool. Expected amounts of radiation produced by the spent fuel and X-ray accelerator implies diverse aspects need to be verified to ensure adequate radiological zoning and personnel radiation protection. A computational methodology was devised to validate the Collimators design by means of coupling different engineering codes. In summary, several assessments were performed by means of MCNP5v1.60 to fulfil all the radiological requirements in Nominal scenario (TEDE < 25µSv/h) and in Maintenance scenario (TEDE < 2mSv/h) among others, detailing the methodology, hypotheses and assumptions employed.

Multiple Methods for Assessing the Dose to Skin Exposed to Radioactive Contamination.

There is the possibility for a worker at a nuclear installation, such as a nuclear power reactor, a fuel production facility or a medical facility, to come in contact with radioactive contaminants. When such an event occurs, the first order of business is to care for the worker by promptly initiating a decontamination process. Usually, the radiation protection personnel performs a G-M pancake probe measurement of the contamination in situ and collects part or all of the radioactive contamination for further laboratory analysis. The health physicist on duty must then perform, using the available information, a skin dose assessment that will go into the worker's permanent dose record. The contamination situations are often complex and the dose assessment can be laborious. This article compares five dose assessment methods that involve analysis, new technologies and new software. The five methods are applied to 13 actual contamination incidents consisting of direct skin contact, contamination on clothing and contamination on clothing in the presence of an air gap between the clothing and the skin. This work shows that, for the cases studied, the methods provided dose estimates that were usually within 12% (1σ) of each other, for those cases where absolute activity information for every radionuclide was available. One method, which relies simply on a G-M pancake probe measurement, appeared to be particularly useful in situations where a contamination sample could not be recovered for laboratory analysis.

Comparative studies of radiation-protection fillers for composite materials based on fosfogipsum binder

The results of comparative experimental studies of the effect of various radiation-protection (RP) fillers for composite materials based on phosphogypsum binder on their RP properties were considered. The regularities of the influence of the parameters of X-ray protection structures, such as thickness, RP filler concentration, composite material density and matrix, etc. on the level of radiation protection of personnel taking into account the properties of phosphogypsum-based composite materials were established and, thus, creation technology parameters and efficiency of such structures were substantiated. The high efficiency of the rare earth elements (REE) as RP fillers for the phosphogypsum binder at a concentration of 30% by weight is associated with high RP properties at significantly lower cost compared to other investigated RP fillers. Comparative experimental studies have convincingly shown that REE are technologically advanced and the most efficient RP filler for gypsum binder, which offers the prospect of creating X-ray protection means (including collective) of a new technological level.

Critères de qualité de la radiothérapie

Quality in radiation oncology requires the creation, organization and daily management of a quality program. Rapid and important improvements are observed in this field, requiring human and financial investments. Radiation protection of personnel and public must take into account the existing regulation texts. The experience feedback committee (Comité de retour d'expérience, Crex) contributes to these regular and important improvements. Its formalization in each radiation oncology department is now unavoidable in terms of safety-management system. The cost of quality assurance must be taken into account in radiation treatment valorization, which seems to be still difficult.

Implication of new International Commission on Radiological Protection dose limit for eye lens: A brief review of TECDOC-1731

ICRP now recommends an equivalent dose limit for the lens of the eye of 20 mSv in a year, averaged over defined periods of 5 years, with no single year exceeding 50 mSv. In December 2013, IAEA brought out a TECDOC-1731, entitled “Implications for occupational radiation protection of the new dose limit for the lens of the eye,” providing interim guidance for application of the limit in operational settings of planned exposure situations. This brief review article is an attempt to bring out salient features of document for the benefit of the readers and operational radiation protection personnel.

Sécurité en curiethérapie

No technique can now be used without previously considering the safety of patients, staff and public and risk management. This is the case for brachytherapy. The various aspects of brachytherapy are discussed for both the patient and the staff. For all, the risks must be minimized while achieving a treatment of quality. It is therefore necessary to establish a list as comprehensive as possible regardless of the type of brachytherapy (low, high, pulsed dose-rate). Then, their importance must be assessed with the help of their criticality. Radiation protection of personnel and public must take into account the many existing regulation texts. Four axes have been defined for the risk management for patients: organization, preparation, planning and implementation of treatment. For each axis, a review of risks is presented, as well as administrative, technical and medical dispositions for staff and the public.

Optimisation of nasal swab analysis by liquid scintillation counting

When responding to an emergency radiological incident, rapid methods are needed toprovide the physicians and radiation protection personnel with an early estimation ofpossible internal dose resulting from the inhalation of radionuclides. This information isneeded so that appropriate medical treatment and radiological protection controlprocedures can be implemented. Nasal swab analysis, which employs swabs swiped inside anostril followed by liquid scintillation counting of alpha and beta activity on theswab, could provide valuable information to quickly identify contamination ofthe affected population. In this study, various parameters (such as alpha/betadiscrimination, swab materials, counting time and volume of scintillation cocktail etc) wereevaluated in order to optimise the effectiveness of the nasal swab analysis method. Animproved nasal swab procedure was developed by replacing cotton swabs withpolyurethane-tipped swabs. Liquid scintillation counting was performed using a Hidex300SL counter with alpha/beta pulse shape discrimination capability. Results show thatthe new method is more reliable than existing methods using cotton swabs andeffectively meets the analysis requirements for screening personnel in an emergencysituation. This swab analysis procedure is also applicable to wipe tests of surfacecontamination to minimise the source self-absorption effect on liquid scintillation counting.