Ensuring Radiation Safety Research Articles

A prototype neutron dose measuring instrument based on prompt gamma detection

Neutron detection and the measurement of ambient dose equivalent are essential to ensure radiation safety in the workplace neutron environment existing in neutron-generating facilities, like particle accelerators, nuclear reactors and other neutron-generating facilities. Based on the measurement of the prompt gammas emitted from elements like hydrogen, boron and carbon, consequent to neutron interactions, a prototype neutron dose measuring instrument has been fabricated using high-density polyethylene and borated high-density polyethylene. This instrument provides an optimized response that closely approximates the fluence to dose conversion coefficients recommended by the International Commission on Radiological Protection (ICRP) to estimate the ambient neutron dose equivalent. Experimental evaluation of the performance of the instrument has been done using neutrons emitted from a 241 Am-Be source, kept inside a concrete enclosure with a square opening on one side. The present system can measure neutron dose with a match of about 5% with theoretical estimates and an existing rem-meter. The measured minimum detection level (MDL) of the instrument is 8.35 μSvh-1 in the presence of significant gamma background and can be improved using a larger NaI(Tl) detector.

Laboratory Radioactive Protection and Safety Management

In order to strengthen the safety management of radioactive laboratories, ensure the safety of laboratory radioactive protection and management, This paper, according to the relevant national laws and regulations, combined with the characteristics and commitment of radioactive laboratories, analyzed the existing hazards, the protection and management measures that should be taken during radioactivity laboratories or in radioactive practice. Adhere to the principle of ″prevention in the first place and integrating prevention with control″ to ensure radiation safety, and environmental pollution.

Программа профессиональной переподготовки кадров медицинских физиков для лучевой терапии

The article assesses the personnel situation in the field of domestic radiation therapy and nuclear medicine. Despite the fact that in recent years there has been a significant re-equipping of Russian medical centers with the latest devices, the quantitative indicators of medical equipment normalized for the number of residents of the country are still significantly inferior to the indexes other countries. And this problem is greatly aggravated by the insufficient number of specialists who can work on the equipment supplied. First and foremost, this refer to medical physicists who are responsible not only for ensuring the required accuracy when applying a dose of ionizing radiation to the tumor, but also for ensuring radiation safety when working with sources of ionizing radiation.
 A continuing vocational educational retraining program covering development, operation and application of high-tech systems for radiotherapy is being proposed. This program was developed and tested at the Department of Physics of Accelerators and Radiation Medicine of the Physical Faculty of M.V. Lomonosov Moscow State University with the support of the Rusnano Foundation for Educational Programs.
 The co-executors in the development and approbation of the Program were the National Medical Research Center of Radiology, A.I. Burnasyan Federal Medical Biophysical Center of the FMBA of Russia. Invited experts in the process of developing the Program were scientists and specialists of the Bauman MSTU, Tomsk Polytechnic University, NRNU MEPhI, N.N. Blokhin National Medical Research Center of Oncology. As a result of a professional educational program, the necessary professional skills for working as specialists in radiotherapy units and nuclear medicine centers are formed, which will successfully solve the problem of professional human resources for the clinical centers of Russia.
 The program was developed and successfully implemented at the Department of Physics of Accelerators and Radiation Medicine of the Physics Department of M.V. Lomonosov Moscow State University.
 The need to develop a program of assessment of medical physicists, which are working at the moment, is being considered. This will guarantee a high level of knowledge necessary for full participation in the medical process and making responsible decisions on the therapeutic use of radiation devices and ensuring radiation safety of patients and personnel.

Радіоекологічні дослідження у лісових екосистемах України

Проаналізовано основні наукові публікації і нормативні документи щодо ведення лісового господарства в умовах радіоактивного забруднення. У процесі досліджень порушено такі проблеми: вивчення міграції радіонуклідів у лісових екосистемах, санітарно-гігієнічні, обгрунтування лісокористування, здійснення лісогосподарських заходів, економічні. Проведені дослідження дали змогу вченим обґрунтувати новий напрям у лісівництві – радіоекологію лісових екосистем, а також регламентувати використання продукції лісового господарства та проведення лісогосподарських заходів на територіях, забруднених радіонуклідами.

Calculation of the shielding safety of Computed Tomography scanner room by using MCNP5 code

Shielding design of Computed Tomography scanner room is a vital work to ensure radiation safety for medical physicists and public. In this paper, we measured CTDI (CT Dose Index) and determined the normalization factor between Monte Carlo simulation and experiment values of absorbed dose. Then, the absorbed dose distribution inside and outside the CT scanner room were surveyed for the variation of the room size. In addition, the influence of photons scattered from the shielding material to patients while shrinking the sizes of the room is also studied in this work.

Анализ международных подходов к обеспечению радиационной безопасности населения и окружающей среды при реабилитации объектов и территорий, загрязнённых в результате прошлой деятельности предприятий ядерного топливного цикла

Анализ международных подходов к обеспечению радиационной безопасности населения и окружающей среды при реабилитации объектов и территорий, загрязнённых в результате прошлой деятельности предприятий ядерного топливного цикла

Sustainability of the European training and education of the medical physics expert in diagnostic radiology (EUTEMPE-RX)

Introduction EUTEMPE-RX ( http://www.eutempe-rx.eu/ ) is an EU funded project that provides state-of-the-art education for Medical Physicists in diagnostic and interventional radiology at expert level. Its sustainability is crucial for the high level of education and training of Medical Physicists in this specialty hence ensuring radiation safety in Europe and beyond. Purpose To present the plans for a sustained continuation of EUTEMPE-RX under the umbrella of the EUTEMPE Network. Materials and methods The work-out of a business plan for sustainability of the EUTEMPE-RX course modules is a project task. Given the overwhelming level of satisfaction expressed by the present EUTEMPE-RX participants, the quality EUTEMPE-RX manual was considered the best basis for future actions. The present modules will be repeated and parallel programmes will be developed for Nuclear Medicine and Radiation Oncology. Results The major sustainability achievements so far have been the creation of a Memorandum of Understanding for continued efforts among current project partners and the foundation of the EUTEMPE network. The structure, quality manual and terms of reference for the Boards and Committees of the EUTEMPE Network have been established and the population of these is being solicited. The programme for the second round of EUTEMPE-RX modules will be available soon. Conclusion A sustainability business plan for EUTEMPE-RX is being developed. The EUTEMPE-RX modules will be repeated in the near future and possibly expanded to other specialties of medical physics. Demand will decide the sustainability of EUTEMPE Network. Disclosure The authors declare that they have no conflict of interest.

Predictive analysis of shaft station radon concentrations in underground uranium mine: A case study

This paper presented a method for predicting shaft station radon concentrations in a uranium mine of China through theoretical analysis, mathematical derivation and Monte-Carlo simulation. Based upon the queuing model for tramcars, the average waiting time of tramcars and average number of waiting tramcars were determined, which were further used in developing the predictive model for calculating shaft station radon concentrations. The results exhibit that the extent of variation of shaft station radon concentration in the case study mine is not significantly affected by the queuing process of tramcars, and is always within the allowable limit of 200 Bq m−3. Thus, the empirical limit of 100,000 T annual ore-hoisting yields has no value in ensuring radiation safety for this mine. Moreover, the developed model has been validated and proved useful in assessing shaft station radon levels for any uranium mine with similar situations.

Criteria for evaluation of building materials hazard based on their natural radioactivity in Russia and in the European Union countries

We hereby have considered the natural radioactivity of building materials as a source of radiation for the human environment. We have considered the Russian and the European evaluation criteria for ensuring radiation safety of the population. We also present an experimental research of the content of natural radionuclides in building materials. We have calculated the effective specific activity and the activity concentration index based on the results presented. We have identified discrepancies between the Russian and the European standards.

A study on plain radiography rooms in Sri Lanka with emphasis on radiation protection

Aim: To ensure radiation safety, the design of X-ray Rooms require consideration of various aspects including size of the room, shielding requirements, wall thickness, distance from focal spot to operator, the warning light, lead lined doors etc. Methods: Data was collected from sixty three X-ray rooms in twenty seven hospitals. Results: Results show 89% of X-Rooms are larger than recommended size of 20 m 2 . 64 % had sufficient wall thickness. Only 12.5% had warning lights but 95.3% had lead lined doors. TLD and protective aprons were available in majority of hospitals. Conclusion: Therefore, some of the plain X-ray rooms surveyed need design improvements to comply with recommended guidelines. A larger detailed study is needed to assess overall impact from these findings on general population. DOI: http://dx.doi.org/10.4038/sljr.v1i0.3 Sri Lanka Journal of Radiology Vol.1 2015: 13-18

Mechanisms and biological importance of photon-induced bystander responses: do they have an impact on low-dose radiation responses.

Elucidating the biological effect of low linear energy transfer (LET), low-dose and/or low-dose-rate ionizing radiation is essential in ensuring radiation safety. Over the past two decades, non-targeted effects, which are not only a direct consequence of radiation-induced initial lesions produced in cellular DNA but also of intra- and inter-cellular communications involving both targeted and non-targeted cells, have been reported and are currently defining a new paradigm in radiation biology. These effects include radiation-induced adaptive response, low-dose hypersensitivity, genomic instability, and radiation-induced bystander response (RIBR). RIBR is generally defined as a cellular response that is induced in non-irradiated cells that receive bystander signals from directly irradiated cells. RIBR could thus play an important biological role in low-dose irradiation conditions. However, this suggestion was mainly based on findings obtained using high-LET charged-particle radiations. The human population (especially the Japanese, who are exposed to lower doses of radon than the world average) is more frequently exposed to low-LET photons (X-rays or γ-rays) than to high-LET charged-particle radiation on a daily basis. There are currently a growing number of reports describing a distinguishing feature between photon-induced bystander response and high-LET RIBR. In particular, photon-induced bystander response is strongly influenced by irradiation dose, the irradiated region of the targeted cells, and p53 status. The present review focuses on the photon-induced bystander response, and discusses its impact on the low-dose radiation effect.

Development of high-sensitivity neutron detectors and measurements at the TPS LINAC

TPS LINAC is essentially concatenated by three consecutive sections of linear accelerators with a nominal output of 2.25 W (150 MeV, 5 nC, 3 Hz) electron beam. A 15 m long transfer line used to guide accelerated electrons from the LINAC outlet to the beam dump. For ensuring radiation safety of personnel around the area, gamma-ray and neutron dose rates outside the LINAC room were repeatedly measured and reviewed during the commissioning. If all the accelerated electrons are perfectly dumped as we wish, radiation dose rates outside the shielding should be as low as comparable to the natural background level. To be able to clearly identify radiation changes above background levels and perform reliable dose rate measurements, high-sensitivity radiation detectors are necessary. This paper presents the design and characteristics of these detectors and a data analysis of the measured results taken during a full-power LINAC operation. NSRRC is now constructing its second light source facility called Taiwan Photon Source (TPS) to meet the increasing demand for brighter synchrotron X-ray source. Focusing on a low-emittance design, the TPS will become one of the brightest synchrotron light sources in the world. The accelerator system consists of a 3.0-GeV electron storage ring with a circumference of 518.4 m, a concentric booster synchrotron with a circumference of 496.8 m, and a pre-injector of 150-MeV electron LINAC. Due to some delay of the TPS civil construction, NSRRC has built a simple rectangular shielding room made of 1 m thick concrete for the assembly and acceptance test of the outsourcing LINAC.

The journey from proton to gamma knife.

It was generally accepted by the early 1960s that proton beam radiosurgery was too complex and impractical. The need was seen for a new machine. The beam design had to be as good as a proton beam. It was also decided that a static design was preferable even if the evolution of that notion is no longer clear. Complex collimators were designed that using sources of cobalt-60 could produce beams with characteristics adequately close to those of proton beams. The geometry of the machine was determined including the distance of the sources from the patient the optimal distance between the sources. The first gamma unit was built with private money with no contribution from the Swedish state, which nonetheless required detailed design information in order to ensure radiation safety. This original machine was built with rectangular collimators to produce lesions for thalamotomy for functional work. However, with the introduction of dopamine analogs, this indication virtually disappeared overnight.

Biodistribution and radiation dosimetry of [18F]-5-fluorouracil

PurposeTo estimate the radiation dose and biodistribution of 18F-5-fluorouracil ([18F]-5-FU) from positron emission tomography/computed tomography (PET/CT) data, and to extrapolate mouse data to human data in order to evaluate cross-species consistency. MethodsFifteen cancer patients (head and neck cancer (n=11), colon cancer (n=4)) were enrolled. Sequential PET/CT images were acquired for 2h after intravenous administration of [18F]-5-FU, and the percent of the injected dose delivered to each organ was derived. For comparison, [18F]-5-FU was administered to female BALB/cAJcl-nu/nu nude mice (n=19), and the percent of the injected dose delivered to mouse organs was extrapolated to the human model. Absorbed radiation dose was calculated using OLINDA/EXM 1.0 software. ResultsIn human subjects, high [18F]-5-FU uptake was seen in the liver, gallbladder and kidneys. The absorbed dose was highest in the gallbladder wall. In mice, the biodistribution of [18F]-5-FU corresponded to that of humans. Estimated absorbed radiation doses for all organs were moderately correlated, and doses to organs (except the gallbladder and urinary bladder) were significantly correlated between mice and humans. The mean effective [18F]-5-FU dose was higher in humans (0.0124mSv/MBq) than in mice (0.0058mSv/MBq). ConclusionBiodistribution and radiation dosimetry of [18F]-5-FU were compared between humans and mice: biodistribution in mice and humans was similar. Data from mice underestimated the effective dose in humans, suggesting that clinical measurements are needed for more detailed dose estimation in order to ensure radiation safety. The observed effective doses suggest the feasibility of [18F]-5-FU PET/CT for human studies.

Ensuring Radiation Safety to Staff in Lymphatic Tracing and Sentinel Lymph Node Biopsy Surgery – Some Recommendations

Introduction: Lymphatic mapping and sentinel node biopsy (LM/ SNB) techniques for melanoma and breast cancer management potentially expose staff, including operating theatre personnel, radiologists, pathologists and others, to ionising radiation. Aims: To ascertain exposure levels in a practical setting and to establish safe work practices for staff involved in the LM/ SNB procedure pathway. Methods: Cumulative intra-procedural extremity (hands) and whole body radiation doses were recorded separately for surgeons, pathologists and couriers during standard sentinel lymph node biopsy procedures from 13 melanoma and included also radiologists in 11 breast cancer cases. Results: The measured extremity dose for melanoma procedures was zero for surgeons and pathologists. The extremity dose for breast cancer procedures was approximately 250 μSv for surgeons, and about 10 μSv for pathologists per breast procedure if done on the day of surgery, but is otherwise negligible; zero for the radiologist; and zero for the courier. No whole body dose was detectable for any staff member. Conclusions: Using the international limit for skin dose some 200 breast cancer procedures could be performed per annum per surgeon (at the general public radiation limit) – and 2000 breast surgical procedures (at the radiation worker limit) based on extremity doses. Radiologists, pathologists and couriers received minimal or zero radiation doses from handling breast specimens. Melanoma procedures showed no measurable dose. Some recommendations for effective safe work practices are given.

Lead aprons: how protected are you?

Lead aprons: how protected are you?

On radiation protection at the LINAC-800 linear electron accelerator

The Automatic System of Radiation Safety Control (ASRSC) of the LINAC-800 linear electron accelerator is designed to ensure radiation safety for accelerator personnel during regular operations and in emergency cases. The results of calculating the emission power used to develop the ARPS are given. Both hardware and software components of the radiation control system are described. This paper also presents a description of the interlock and signalization system.

The Radioactivity Levels and Safety Assessment of Building Materials in Nanjing, Jiangsu Province, China

In order to invetigate the natural radioactivity levels of typical building materials in Nanjing, Jiangsu Province,China, the specific activities of natural radionuclides (226Ra,232Th and40K) in samples of building materials were measured by ORTEC HPGe gamma ray spectrometer. And the radium equivalent activity, the internal and external exposure index, and relative annual effective dose equivalents were also claculated. The average concentrations of all the samples ranged from 64 to 318.79 Bq·kg-1, 11.35 to 144.83 Bq·kg-1and 92.57 to 951.68 Bq·kg-1for226Ra,232Th and40K, respectively. Their average values were in the ranges: 0.33-1.50 for the internal exposure index (Ira); 0.29-1.51 for the external exposure index (Ir); 0.34-1.74 mSv·a-1 for HEextand 0.36-1.76 mSv·a-1for HEint. The average radium equivalent activity varied from 106.49 to 541.77 Bq·kg-1. According to the standard, most samples were in a lower radioactivity level expect a few of artificial tiles. But, we must perfect detection and management system of many materials to ensure radiation safety and physical health.

Prevalence and Risk Factors for Cervical and Lumbar Spondylosis in Interventional Electrophysiologists

The volume and complexity of interventional electrophysiology procedures have increased greatly over the last 20 years. Anecdotal reports from Canada and elsewhere have suggested an important prevalence of neck and back problems in interventional electrophysiologists. To quantify the scope of neck and back problems, we surveyed 70 interventional electrophysiologists in Canada using an electronic survey with in person and email reminders. We also surveyed an age- and gender-matched group of noninterventional cardiologists. We received responses from a total of 58 of 70 interventional electrophysiologists (response rate 82.8%). There was a significantly higher prevalence of cervical spondylosis among electrophysiologists compared to matched noninterventional cardiologists (20.7% compared to 5.5%, P = 0.033). There was a trend for increased prevalence of lumbar spondylosis (25.9% compared to 16.7%, P = 0.298). Among electrophysiologists, those with cervical spondylosis were older (49.83 ± 10.48 years compared to 44.57 ± 9.20, P = 0.092) and had worked in the specialty for longer in comparison to unaffected physicians (19.67 ± 10.06 years compared to 13.37 ± 8.97 years, P = 0.039). All other variables including gender, height, weight, BMI, type of lead, weekly average lead time, and % of time standing in electrophysiology laboratory were not different. On multivariable analysis there were no independent predictors of disease. There is a significant increased prevalence of cervical spondylosis among interventional electrophysiologists. Programs to improve ergonomics and minimize time spent wearing lead are needed. The same vigilance that is used to ensure radiation safety in the laboratory should be applied to create ergonomic safety.

Quantitative criteria for rehabilitation of the territory of shore servicing bases of the naval fleet

A variant of the application of the norms and regulations currently operating in our country which ensure radiation safety for workers, the general public, and the environment is presented to valdiate the criteria for rehabilitation of the territory of the shore servicing bases of the naval fleet. The main normative-legal documentation on the rehabilitation of the radiation dangerous objects is analyzed and the international and domestic experience in performing such work, including radiation accidents, is examined. The quantitative criteria used in practice for the residual radioactive contamination of industrial objects and housing developments and the environment are singled out, and an attempt is made, on the basis of a generalization of the information available, to adapt individual tenets in the interests of rehabilitation of radiation dangerous shore-based objects of the fleet.