Radiation Protection Guidelines Research Articles

Radiation protection and personal dosimetry in a core facility for multimodal small animal imaging.

Clinical imaging techniques such as positron emission tomography (PET) in combination with computed tomography (CT) are increasingly being used in biomedical research involving small animal models. The handling of open radioactive substances (radiopharmaceuticals) necessary for PET imaging requires prior official authorization for handling, the application of radiation protection principles, and regular training. The overriding aim of radiation protection is to protect the personnel directly involved, other persons, and the environment from the harmful effects of ionizing radiation.This paper aims to provide an overview of the regulatory requirements of the Radiation Protection Act (StrlSchG), the Radiation Protection Ordinance (StrlSchV), and the associated standards and guidelines. Furthermore, their implementation in practical work in small animal imaging using PET/CT is shown. We will focus on the individual steps of the imaging process, from delivery of the radiopharmaceuticals to waste disposal. This should provide interested researchers with an initial overview of the safe and successful use of the method. In addition, exposure values from the last six years in the literature were analyzed. While personal dosimetric monitoring in clinical PET/CT imaging has been extensively published, there is no published data known to us for personnel for PET/CT research with small animals. The evaluation of the personal dosimetric monitoring of our small animal imaging facility with 7 employees over 4 years revealed an increased personal and finger dose normalized to the injected activity and compared to human PET/CT imaging. Nevertheless, the annual personal dose or annual finger dose in small animal imaging (Hp(10): 1.7 mSv, Hp(0.07): 64 mSv) is lower than for personnel performing human PET/CT imaging at the local University Department of Nuclear Medicine (Hp(10): 3.8 mSv, Hp(0.07): 156 mSv) or published values, and is well below the legally permissible maximum dose of 20 or 500 mSv per year.The increasing use of PET/CT in small animal research can be safely utilized if the radiation protection principles are implemented and continuously trained. · PET/CT imaging in small animals is increasingly used in biomedical research.. · Radiation protection laws and guidelines have to be known and are relevant in animal experiments.. · Compared to published values from human medicine, activity-specific employee doses are increased in the presented imaging facility.. · The legal personal dose in the studied imaging facility is below legal limits.. · Schildt A, Sänger P, Lütgens M et al. Radiation protection and personal dosimetry in a core facility for multimodal small animal imaging. Fortschr Röntgenstr 2024; DOI 10.1055/a-2462-2419.

Beyond one million years: The intrinsic radiation hazard of high-level nuclear wastes

Abstract This paper highlights the absence of quantitative estimates regarding the intrinsic radiation hazard of high-level nuclear wastes, namely, spent fuel (SF) and vitrified high-level wastes (VHLW), for periods exceeding one million years. Using available data, conducting scoping calculations of radiation doses, and comparing the results to radiation protection guidelines and natural background radiation, this paper shows that high-level wastes cannot be safely handled or left unprotected essentially indefinitely. By quantitatively evaluating the dose rates of unshielded SF and VHLW, this study identifies critical new insights, such as the roles of the Np-237 decay chain; the eventual, long-term dominance of the U-238 decay chain; and the interplay of three actinide decay chains, including the significant role of Bi-214. These findings fill a gap in the literature and emphasize the need for more detailed investigations in this as-yet-unexplored research area, which has a direct bearing on technical and societal decision-making for both waste disposal safety and the choice of the back end of the nuclear fuel cycle.

Assessment of Practice of Radiation Protection Devices in Fluoroscopy in SKIMS SOURA Hospital Srinagar J&K

This study evaluated radiation protection practices in fluoroscopy at Sher-i-Kashmir Institute of Medical Sciences (SKIMS) in Soura, Jammu and Kashmir. A descriptive cross-sectional design involved observing 47 patients and medical professionals during radiological procedures in the gastroenterology and radiology departments. Data were collected using a chart table, focusing on the use of radiation protection apparel and devices. Results showed that 50% of patients were aged 26-35, with an equal gender ratio. Thyroid shields were used by 56.7% and gonad shields by 36.7% of patients. Among radiation technologists, 75% were aged 30-40 and all used lead aprons and thyroid shields. Radiologists were evenly split by age and gender, with all using lead gloves, thyroid shields, collimators, and filters. The findings indicate that SKIMS staff exhibit strong knowledge and adherence to radiation protection guidelines, providing adequate safety measures for patients and themselves.

Electromagnetic simulation and electromagnetic safety characteristics analysis of implantable medical devices in wireless charging processes

In recent years, wireless charging technology for electric vehicles has received increasing attention. Existing research has been limited to the safety of specific body parts in the electromagnetic environment of wireless charging for electric vehicles, with insufficient consideration for the overall human body and the electromagnetic safety of implanted medical devices. In order to assess its safety in the electromagnetic environment more comprehensively, a three-dimensional electromagnetic simulation software based on the finite element method is used to construct models of the human body and implanted medical devices in the electromagnetic environment of wireless charging for electric vehicles. The study aims to investigate the impact of this electromagnetic environment on the human body and implanted medical devices. The results indicate that, except for the maximum magnetic induction of 0.47 μT at the ankle, which exceeds the limit, the magnetic induction intensity and electric field strength in important tissue areas, especially the upper trunk of the human body, are both below the safety limits specified by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. For implanted cardiac pacemakers, the effective and peak magnetic field strengths are 13.7 A/m and 19.4 A/m, respectively, when the coil input power is 22 kW, meeting the relevant magnetic field strength requirements. The maximum temperature rise of the pacemaker is 3.2 × 10-3∘C, and there are no significant changes in the temperature of the major organs in the human body after the implantation of the pacemaker. The thermal effects of electromagnetic waves on the temperature rise caused by implanted cardiac pacemakers have minimal impact on the human body.

Monte Carlo simulation analysis of radiation attenuation properties induced by arsenic accumulation in femur and tibia bones of rats exposed to sodium arsenite diet

PurposeThe study aims to investigate the effect of sodium arsenite (NaAsO2) on radiation permeability in biological tissues of rats, challenging existing literature claims about NaAsO2's influence on the density of bones. The motivation is determining whether exposure alters radiation permeability within a defined range of radiological energy. Should any changes be observed, radiation protection guidelines may necessitate the use of lower energy levels in imaging procedures involving such exposure. This consideration is vital for ensuring adherence to radiation safety standards, particularly in medical imaging, where minimizing patient and operator exposure to radiation is paramount. Materials and methodsIn this study, rats were divided into two groups: a control group and a NaAsO2-treated group. After the treatment period, these animals were euthanized to collect their femurs and tibias for further analysis. The elemental composition of these bones was then meticulously examined using Scanning Electron Microscopy (SEM), enhanced by Energy-dispersive X-ray Spectrometry (EDX). Monte Carlo Simulation codes of MCNP6 and PHITS 3.22 were used for investigate photon induced interactions. These powerful tools allowed us to assess the gamma-ray attenuation properties of the collected samples. For an accurate comparison and analysis, we referred to the NIST database using the WinXCom program. Furthermore, the study explored the effects of charged particles on the bone samples, employing the SRIM code for this purpose. This part of the research was crucial to understanding the interactions at a more detailed level. We calculated the photon attenuation parameters for radiological energies up to 0.5 MeV and also investigated the interactions of charged particles with energies as high as 15 MeV. ResultsIn groups treated with NaAsO2, while there is less reduction in mass attenuation coefficients, larger differences have been observed in linear attenuation coefficients. Notably, a decrease in the linear attenuation coefficient has been observed in the NaAs Tibia group. ConclusionThe application of sodium arsenite (NaAsO2) results in a reduction in the Linear Attenuation Coefficient, necessitating a detailed investigation to determine whether this decrease also affects the Hounsfield unit, in accordance with the ALARA (As Low As Reasonably Achievable) principle that guides radiation safety protocols.

Computational analysis of electromagnetic field exposure in passengers near high- current contact wire environments.

The electromagnetic environment of a railway station is composed of electrical, magnetic, and electromagnetic fields, which are generated by various sources such as traction current, voltage, pantograph-catenary arc, locomotive braking, wheel-rail rolling arc, and communication systems. However, there is public growing concern among the public about the potential negative human health effects of this electromagnetic environment. To analyze the distribution of electromagnetic fields in human tissues, electromagnetic simulation software is used to create a model that includes six track contact wires and four waiting passengers on three platforms. This model is used to analyze the magnetic field environment created by high currents in the contact wires of a multi-track high-speed railway station. By varying the loads on different contact wires, the distribution of electric field and magnetic flux density within human tissues of waiting passengers on different platforms is studied using this model. When the track is unoccupied, the calculation results show that the maximum values of the electric field and magnetic flux density of the passenger's human body tissue at the blind way on the platform and 1m of the blind way are 17.6mVm-1 and 52.7 μT, respectively. These values increase by 9.28mVm-1 and 16.4 μT compared to when the track is occupied. When more contact wires are loaded with currents, the electric field mode and magnetic flux density mode of human tissues increase at the same position on the platform. Specifically, when the contact wires of six tracks are loaded with current at the same time, the maximum values of the electric field mode and magnetic flux density mode of the waiting passengers' human tissues at the blind way on different platforms are 29.6mVm-1 and 88.1 μT, respectively. These maximum values are lower than the public electromagnetic exposure limits that are designated by the International Commission on Non-Ionizing Radiation Protection guidelines. The research results demonstrate that the magnetic field environment generated by the current in the contact wires of a railway station with six tracks does not pose a health risk to human tissues of passengers waiting at the blind way and 1m of the blind way on the platform. These findings can provide valuable data reference for the formulation of relevant standards for the design of electrified rail transit, as well as the suppression of electromagnetic interference and protection of human bioelectromagnetism.

Upotreba ručnog radiografskog uređaja za intraoralno snimanje u suvremenoj stomatološkoj praksi

Recently, there has been an increased interest in the utilization of a handheld X-ray devices for intraoral imaging in modern dental practice. Globally, several documents with recommended guidelines on the utilization of a handheld X-ray device for intraoral imaging have been issued. Considering that the recommended guidelines were contradictory, additional research was initiated on the justification of manual utilization in everyday practice. The goal of this article is to present the justification for the utilization of a handheld X-ray devices as an alternative to wall mounted fixed devices that has been presented by several studies that examined the level of radiation received by the operator, the environment and the patient. In the interest of research, the emphasis was also on the radiological image quality control. Although the results of the quality parameters on the radiological image with both types of devices proved to be successful, the results of the radiation dose oscillated and were not completely acceptable for the operator, the environment and the patient, if all radiation protection guidelines were not followed. Further research should be done additionally on people, instead on models and phantoms, before they are fully introduced into everyday dental practice.

Design of prehospital spectral CT with a rotation-free rectangular gantry and deep learning reconstruction

Treatment of stroke depends on a narrow therapeutic time window and requires urgent intervention to be emergently pursued. Despite recent “fast” initiatives that have underscored “time is brain,” many patients still fail to present within the narrow time window to receive maximum treatment benefit from advanced stroke therapies. The convergence of emergency medical services, telemedicine, and mobile technology, including transportable computed tomography scanners, has presented a unique opportunity to advance patient stroke care in the prehospital field by shortening the time to hyperacute stroke treatment with a mobile stroke unit. However, in order to facilitate the integration of computed tomography (CT) scanners into small ambulances, their geometry should be streamlined and made compact. Additionally, it is imperative that radiation exposure from prehospital CT scans comply with established radiation protection guidelines to safeguard both patients and healthcare workers. In this study, we propose a newly designed CT system for a rotation-free rectangular gantry with a photon-counting detector (PCD) and a deep-learning reconstruction approach for undersampled projections. Undersampled projections obtained using the designed CT system were implemented using a deep learning method. The deep learning approach showed superior image quality without distortion compared to state-of-the-art reconstruction methods. Finally, we implemented imaging of brain microhemorrhages using low- and high-energy images obtained from the PCD. Our results indicate that the proposed scanner effectively shows potential for acute stroke detection in prehospital ambulances. Its effectiveness was validated by comparing its image performance with those of other methods such as FBP and compressed sensing.

Knowledge and practice of radiation safety in Brazilian equine veterinarians are less than optimal: An online survey.

Exposure to ionizing radiation is an occupational risk for veterinarians due to the potential for carcinogenesis, reproductive disorders, cataracts, and hereditary genetic changes. This survey study aimed to identify the radiological protection practices routinely used by veterinarians who work with portable digital X-ray equipment in horses in Brazil and assess their knowledge regarding current legislation. A total of 120 voluntary participation questionnaires were sent to veterinarians who used portable digital radiographic equipment in horses nationwide. The frequencies of the answers were analyzed using the chi-square test and logistic regression models. Thirty-five veterinarians responded (29% response rate). Of these, there was a greater participation of professionals in public institutions (40%, 14/35, p<.001), with 69% from the southeast region (24/35, p<.001) and 69% (24/35, p=.028) being male. We found that self-employed veterinarians had a higher odds ratio (OR) (9.00; 95% confidence interval (CI) [1.39-58.44]; p=.021) of not using personal protective equipment compared with those in professional public institutions. In addition, not knowing the current legislation Collegiate Directorate Resolution 611/22 was a potential risk factor for lower radiological protection (OR, 8.00; 95% CI, [0.79-81.33]; p=0.079). In conclusion, findings indicated that Brazilian equine veterinarians generally do not adopt adequate radiological protection against ionizing radiation during radiographic examinations and have low knowledge of the current legislation. Results can be used as background for the formulation of specific radiation protection guidelines for veterinarians and incentive educational and training strategies to reduce risks inherent to occupational exposure.

Management of pregnant or potentially pregnant patients undergoing diagnostic and interventional radiology procedures: Investigation of clinical routine practice

It is well known that foetuses are highly sensitive to ionising radiation and special attention to justification and optimisation of radiological procedures involving a pregnant patient is required. A task to review, validate and compare different approaches to managing the pregnant patient and to estimating the associated foetal doses arising from a diagnostic or interventional radiology (DIR) procedure was designed in the framework of EURADOS working group 12.As a first step, a survey of radiation protection practice including dosimetry considerations among EURADOS members was performed using online questionnaire. Then, to evaluate the possible differences in the estimated foetal doses, a comparison of assessed dose values was made for three cases of pregnant patients that underwent different CT procedures.More than 120 professionals from 108 institutions and 17 countries that are involved in managing pregnant patients undergoing DIR procedures answered the questionnaire. Most of the respondents use national or hospital guidelines on the management of pregnant patients undergoing DIR procedures. However, the guidelines differ considerably among respondents. Comparison of foetal dose assessments performed by dosimetry experts showed the variety of methods used as well as large variability of estimated foetal doses in all three cases.Although European and International commission on radiation protection guidelines already exist, they are more than 20 years old and, in some aspects, they are obsolete. This paper shows that there is a need to revise and update these guidelines.

Scattered Radiation Distribution Utilizing Three Different Cone-Beam Computed Tomography Devices for Maxillofacial Diagnostics: A Research Study.

This study aimed to estimate scattered radiation and its spatial distribution around three cone-beam computed tomography (CBCT) devices, in order to determine potential positions for an operator to stand if they needed to be inside the CBCT room. The following devices were tested: Morita Accuitomo (CBCT1), Newtom Giano HR (CBCT2), Newtom VGi (CBCT3). Scattered radiation measurements were performed using different kVp, mA, and Field of View (FOV) options. An anthropomorphic phantom (NATHANIA) was placed inside the X-ray gantry to simulate clinical conditions. Scattered measurements were taken with the Inovision model 451P Victoreen ionization chamber once placed at fixed distances from each irradiation isocenter, away from the primary beam. A statistically significant (p < 0.001) difference was found in the mean value of the scattered radiation estimations between the CBCT devices. Scattered radiation was reduced with a different rate for each CBCT device as distance was increased. For CBCT1 the reduction was 0.047 μGy, for CBCT2 it was 0.036 μGy, and for CBCT3 it was 0.079 μGy, for every one meter from the X-ray gantry. Therefore, at certain distances from the central X-ray, the scattered radiation was below the critical level of 1 mGy, which is defined by the radiation protection guidelines as the exposure radiation limit of the general population. Consequently, an operator could stay inside the room accompanying the patient being scanned, if necessary.

Assessment of the Blue Light Ocular Hazard by Solar Measurements and the Impact of Selected Sunglasses Based upon the Limits of the International Commission on Non-Ionizing Radiation Protection Guideline.

A quantitative assessment of the blue light hazard for the human eye related to direct solar irradiation is presented. For six radiation situations, missing eye protection was compared to protection by nine different commercial sunglasses with and without an optimized blue light filter. Measurements of the solar irradiance were performed on Earth's surface as well as at an elevation of 12 km in the cockpit of an airliner. An irradiation time limit was calculated from the measurement data, within which the maximum blue light dose of 100 J m-2, recommended by the International Commission on Non-Ionizing Radiation Protection and mandatory for the safe operation of lamps according to the norm ICE 62471, is reached. The results suggest that the blue light dose limit is violated within less than 3 s when looking without eye protection directly into the sun. For Category 3 sunglasses without the optimized blue light filter, time limits of 10 to 25 s on Earth's surface and 7 to 8 s at 12 km altitude were observed. The investigated Category 3 sunglasses with optimized blue light protection and suited for traffic use allow a time limit of more than 40 s on Earth's surface and 18 to 95 s in the airliner's cockpit. The outcome of the study is that the eye protection against blue light hazard related to solar radiation can be quantified using existing limits and that the choice of sunglasses is relevant: Traffic-worthy sunglasses optimized for protection against blue light hazard offer a better protection than non-optimized sunglasses.

RF Health Safety Limits and Recommendations [Health Matters

The rapid proliferation of cellular mobile telecommunication devices and systems is raising public health concerns about the biological effects and safety of RF radiation exposure. There is also concern about the efficacy of promulgated health safety limits, rules, and recommendations for the RF radiation used by these devices and systems. This article reviews and discusses the U.S. Federal Communications Commission (FCC) notices and rules, International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines, and International Committee on Electromagnetic Safety (ICES) standard for safety levels with respect to human exposure to electric, magnetic, and electromagnetic fields (EMFs). The recently revised RF exposure limits are adjusted only for heating with RF radiation. These limits are largely intended to restrict short-term heating by RF radiation that raises tissue temperatures. They are narrow in scope and are not applicable to long-term exposure at low levels. This review discusses the assumptions underlying the standards and the outdated exposure metrics employed, and concludes that the revised guidelines do not adequately protect children, workers, or the public from exposure to RF radiation or people with sensitivity to electromagnetic radiation from wireless devices and systems. Furthermore, the review discusses important animal data that the standards do not appear to take into account. Moreover, for millimeter-wave radiation from 5G mobile communications, there are no adequate human health effects studies in the published literature. The conclusions by scientific organizations, such as the International Agency for Research on Cancer (IARC), that diverge from these standards are also discussed. The review concludes that many of the recommended limits are debatable and require more scientific justification from the standpoint of safety and public health protection.

Occupational Exposure to Nonionizing Radiation and Risk for Malignancy in Young Adults.

Nonionizing radiation (NIR) is considered "possibly carcinogenic to humans," and therefore, exposure of young military personnel raises concerns regarding increased risk for cancer. The aim of our study was to compare the cancer incidence in exposed and nonexposed populations in order to gain better understanding of their risk. A longitudinal retrospective cohort study, between 2009 and 2018, was conducted. Israel Defense Forces (IDF) aerial defense units service members, with NIR exposure (range of 2-300 GHz, below the International Commission of Non-Ionizing Radiation Protection guidelines), were compared with a similar sociodemographic group of service members without NIR exposure. Both groups were followed for cancer incidence (all-cause and specific malignancies). Kaplan-Meier analysis of cancer-free survival and univariate and multivariable logistic regressions for possible confounders and risk factors were performed. This analysis was repeated on a matched 1:1 control group. Exposure and comparison groups included 3,825 and 11,049 individuals, respectively. Forty-one cases diagnosed with cancer were identified during the follow-up time (mean 4.8 [±2.7] years), 13 (0.34%) of which were reported in the exposure group, and 28 (0.25%) were reported in the comparison group. The odds ratio (OR) for cancer incidence in the exposure vs. control groups was 1.34 (95%CI, 0.70-2.60), P-value = 0.3807. The results remained unchanged after adjustment for sex, age at enrollment, service length, socioeconomic status, and military occupation (adjOR = 1.38 [95%CI, 0.67-2.82], P = 0.3818). Our study did not find an increased short-term risk for cancer in young adults exposed to NIR radiation as compared with unexposed young adults.

The use of protection measures in dento-maxillofacial radiology in Europe: a survey among experts

Patient contact shielding to reduce radiation exposure to radiosensitive organs of patients is known to be used inconsistently in the field of dento-maxillofacial radiology (DMFR). There is an ongoing discussion if its use is still justified with regard to recent technical enhancements in the field. Thus, the aim of this study was to investigate the recommended and applied safety standards regarding dose protection measures in dental radiology within European countries. With an online questionnaire the use of safety measures, especially lead protection and collimation, in different patient groups (adults, children, pregnant women) was interrogated including leading experts in the field of DMFR. Among the 24 participants from 13 different countries, there was a tendency towards lead protection for intraoral radiography and towards collimation for extraoral radiography. Participants based their decision mainly on law and societal guidelines. Overall, the application of radiation protection measures varies within Europe. It seems safe to say that lead protection as a measure of radiation dose limitation is still recommendable even though collimation and technical advancements have led to great dose reductions. Collimation should be used more broadly and a standardization of protection measures and an update of radiation protection guidelines in Europe is desirable. Accepted for publication: September 12, 2022 Published online: September 13, 2022

The use of protection measures in dento-maxillofacial radiology in Europe: a survey among experts.

Patient contact shielding to reduce radiation exposure to radiosensitive organs of patients is known to be used inconsistently in the field of dento-maxillofacial radiology (DMFR). There is an ongoing discussion if its use is still justified with regard to recent technical enhancements in the field. Thus, the aim of this study was to investigate the recommended and applied safety standards regarding dose protection measures in dental radiology within European countries. With an online questionnaire the use of safety measures, especially lead protection and collimation, in different patient groups (adults, children, pregnant women) was interrogated including leading experts in the field of DMFR. Among the 24 participants from 13 different countries, there was a tendency towards lead protection for intraoral radiography and towards collimation for extraoral radiography. Participants based their decision mainly on law and societal guidelines. Overall, the application of radiation protection measures varies within Europe. It seems safe to say that lead protection as a measure of radiation dose limitation is still recommendable even though collimation and technical advancements have led to great dose reductions. Collimation should be used more broadly and a standardization of protection measures and an update of radiation protection guidelines in Europe is desirable.

Sun-Safe Zones: Investigating Integrated Shading Strategies for Children's Play Areas in Urban Parks.

Although Open Space Ratio is a critical control in the Development Approval process, there are no ultraviolet radiation (UVR) protection guidelines for urban parks. This study explores key strategies for shade provision in children's play areas in urban parks, aiming to promote sun-safe play environments against alarming skin cancer trends. The literature review identified primary issues affecting UVR exposure in public venues, and the research comprises a shade audit of Beaton Park in Dalkeith. The methods involved using virtual park modeling and Shadow Analysis simulations to generate the daily average number of hours in shade for each month. Our recommendations based on this analysis are (a) a minimum canopy cover representing 50% of the entire ground cover; (b) a minimum diameter for a shade (umbrella) of about 2.5 times the diameter of the table; and (c) an ideal umbrella height of 90 cm from the table surface. This research proposes a potential nexus between landscape design and a UVR protection framework for child-friendly Sun-safe Zones (SsZ).

Analysis of the Advances of RDC 330/19 in relation to Ordinance 453/98 under the Radiation Protection Focus

Almost twenty years after the publication of Ordinance 453, the National Health Surveillance Agency (ANVISA) approved the Collegiate Board Resolution 330 (RDC 330), which establishes the basic guidelines for Radiation Protection (RP) in diagnostic and interventional radiology and regulates the use of X-ray diagnostic methods throughout the national territory. Therefore, when observing the radiodiagnostic service and its changes suffered in recent decades, the addition of new modalities is noticeable, as well as changes in the service flow, brought about as a result of the advancement of new technologies. The RDC 330 came with several changes even in its format: a document with the basic guidelines for radioprotection and several Normative Instructions (INs) - one for each technology in diagnostic imaging. Among the INs, IN58 and IN59 can be mentioned, which provide for sanitary requirements for quality assurance and safety in ultrasound and magnetic resonance systems, respectively, which now makes quality control mandatory. The RDC 330 and its respective IN were developed to meet all these needs, contextualizing the principles already established for the elevation of the RP culture and diagnostic quality. Therefore, the implementation of RDC 330 is defended, in view of the need for agile adaptation that can ensure improvements in the quality of imaging services, dose optimization and in the quality control of radiodiagnostic equipment, promoting the safety of patients, population and workers exposed to ionizing radiation.

Knowledge, attitude, and practice assessment of pediatric radiation protection guidelines amongst radiographers and radiologists at governmental hospitals in the Gaza Strip.

Introduction: Even small doses of radiation over time can cause cancer and short-term exposure may cause burns or radiation sickness. This study assessed medical radiographers' and radiologists' knowledge, attitude, and practice regarding paediatric radiation protection at Gaza Strip government hospitals. Methods: A cross-sectional analytical study involving quantitative and qualitative data tools was used and conducted at the three main pediatric governmental hospitals, in addition to six general hospitals receiving children in emergency cases. A questionnaire was issued to 176 medical radiographers and radiologists. In-depth interviews were also conducted with nine experts in the radiology field. Results: The knowledge, attitude, and practice scores among radiologists and medical radiographers regarding the radiation protection measures were 63% (moderate), 70% (neutral), and 54% (poor), respectively. Training courses had a significant effect on the level of knowledge regarding radiation protection measures (p = 0.015). Participants working at the pediatric hospitals had better knowledge than those working in the general hospitals (p = 0.013). Participants with previous training had better attitudes than those who had not undertaken training; however, the difference was not statistically significant (t = 1.80, p = 0.077). Conclusion: There is a need for continuous training programmes in radiation protection measures. Physicians, medical radiographers, and radiologists should be provided with written criteria, protocols, and guidelines which should be adopted for all pediatric referrals to imaging. Implications for practice: Consideration should be given to applying pediatric radiation protection measures routinely.

Assessment of incident power density in different shapes of averaging area for radio-frequency exposure above 6 GHz

Objective. The International Commission on Non-Ionizing Radiation Protection guidelines and IEEE C95.1-2019 standard for human protection from local electromagnetic field exposure above 6 GHz state that absorbed (or epithelial) power density (APD) and incident power density (IPD), averaged over a square area, are internal and external physical quantities, respectively, that set the exposure limit. Per exposure standards, the measurement procedure and evaluation of the IPD have been established in technical standards, where a circular averaging area is recommended only for non-planar surfaces in IEC/IEEE 63195-1 and -2. In this study, the effects of two averaging shapes on the APD and IPD are evaluated computationally to provide new insights from the viewpoint of exposure standards. Approach. The relation between the APD, IPD, and the steady-state temperature rise (heating factor) in rectangular and human models for exposure to a single dipole, dipole arrays, and the Gaussian beams is investigated computationally with finite-difference method. Main results. The maximum differences in the heating factor of the APD and IPD for square and circular averaging areas were 4.1% and 4.4% for the antenna–model distance >5 mm, respectively. These differences appear when the beam pattern on the model surface has an elliptical shape. For an antenna–model distance ≤5 mm and at frequencies ≤15 GHz, the heating factors for square averaging areas were not always conservative to those for circular ones (−7.8% for IPD), where only the antenna feed point are visible before beam formation. Significance. The heating factors of the APD and IPD for a circular averaging area are conservative for near-field exposure of canonical sources for frequencies up to 300 GHz, except for a beam with a significant major-to-minor axis ratio and an angle of 30°–60° to a square averaging area. This tendency would help bridge the gap between exposure and product standards.