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The Ionising Radiation Regulations 2017 requires prior risk assessment calculations and regular environmental monitoring of radiation doses. However, the accuracy of prior risk assessments is limited by assumptions and monitoring only provides retrospective evaluation. This is particularly challenging in nuclear medicine for areas surrounding radionuclide therapy patient bathroom wastewater pipework. Machine learning (ML) is a technique that could be applied to patient booking records to predict environmental radiation dose rates in these areas to aid prospective risk assessment calculations, which this proof-of-concept work investigates. 540 days of a dosimeters historical daily average dose rate measurements and the corresponding period of department therapy booking records were used to train six different ML models. Predicted versus measured daily average dose rates for the following 60 days were analysed to assess and compare model performance. A wide range in prediction errors was observed across models. The gradient boosting regressor produced the best accuracy (root mean squared error = 1.10 µ Sv.hr−1, mean absolute error = 0.87 µ Sv.hr−1, mean absolute percentage error = 35% and maximum error = 3.26 µ Sv.hr−1) and goodness of fit (R 2 = 0.411). Methods to improve model performance and other scenarios where this approach could prove more accurate were identified. This work demonstrates that ML can predict temporal fluctuations in environmental radiation dose rates in the areas surrounding radionuclide therapy wastewater pipework and indicates that it has the potential to play a role in improving legislative compliance, the accuracy of radiation safety and use of staff time and resources. [ABSTRACT FROM AUTHOR]

Patients treated with radionuclide therapy usually require restrictions on certain activities for a period of time following treatment to optimise protection of the public and ensure the legal dose limit is not exceeded. Software may be used to calculate necessary restriction periods for an individual based on longitudinal dose rate measurements from the time of radiopharmaceutical administration. A spreadsheet program has been used for this purpose in Australian hospitals for the last two decades. However, this spreadsheet has a limitation in that it uses an approximation in the calculation of dose from a contact pattern, which affects the calculated restriction period. A computer program called Dorn was developed that provides the same functionality as the spreadsheet but without this approximation. Proffered radiation safety advice from Dorn and the spreadsheet were compared. Advice from the spreadsheet and Dorn were compared for 55 patients who underwent iodine-131 therapy for differentiated thyroid cancer. The restriction periods for caring for infants, close contact with children and sleeping with a partner were typically about 13 h longer in Dorn than in the spreadsheet, but in some cases were over a week shorter or a month longer. If the Dorn program is used clinically in place of the spreadsheet, some patients will enjoy shorter restriction periods and the therapy provider can be more confident in their compliance with regulatory requirements and best practice. Dorn is freely available from https://doi.org/jg5f. [ABSTRACT FROM AUTHOR]

Individual monitoring of radiation workers is essential to ensure compliance with legal dose limits and to ensure that doses are As Low As Reasonably Achievable. However, large uncertainties still exist in personal dosimetry and there are issues with compliance and incorrect wearing of dosimeters. The objective of the PODIUM (Personal Online Dosimetry Using Computational Methods) project was to improve personal dosimetry by an innovative approach: the development of an online dosimetry application based on computer simulations without the use of physical dosimeters. Occupational doses were calculated based on the use of camera tracking devices, flexible individualised phantoms and data from the radiation source. When combined with fast Monte Carlo simulation codes, the aim was to perform personal dosimetry in real-time. A key component of the PODIUM project was to assess and validate the methodology in interventional radiology workplaces where improvements in dosimetry are needed. This paper describes the feasibility of implementing the PODIUM approach in a clinical setting. Validation was carried out using dosimeters worn by Vascular Surgeons and Interventional Cardiologists during patient procedures at a hospital in Ireland. Our preliminary results from this feasibility study show acceptable differences of the order of 40% between calculated and measured staff doses, in terms of the personal dose equivalent quantity Hp(10), however there is a greater deviation for more complex cases and improvements are needed. The challenges of using the system in busy interventional rooms have informed the future needs and applicability of PODIUM. The availability of an online personal dosimetry application has the potential to overcome problems that arise from the use of current dosimeters. In addition, it should increase awareness of radiation protection among staff. Some limitations remain and a second phase of development would be required to bring the PODIUM method into operation in a hospital setting. However, an early prototype system has been tested in a clinical setting and the results from this two-year proof-of-concept PODIUM project are very promising for future development. [ABSTRACT FROM AUTHOR]

This work focuses on the determination of the radiation doses for a total sample of 916 children, categorised into four age groups (<1, 1â€"5, <5â€"10, <10â€"15 years) undergoing the most frequent paediatric CT scans performed in different scan facilities in Tunisia in order to establish the national diagnostic reference levels (DRLs). Dose evaluation concerned the dosimetric indicators: volume computed tomography dose index (CTDIvol) and doseâ€"length product (DLP). The different paediatric CT protocols and practices were also evaluated. The results show a large variation in doses between different radiology departments. For head scans, the respective DRLs for children aged <1, 1â€"5, 5â€"10 and 10â€"15 years were 26, 38, 51 and 51 mGy, respectively, for CTDIvol and 384, 664, 873 and 978 mGy cm, respectively, for DLP. For the chest, the equivalent respective DRLs were 8, 10, 12 and 15 mGy for CTDIvol and 118, 330, 442 and 526 mGy cm for DLP. For the abdomen, the respective DRLs were 9, 13, 19 and 18 mGy for CTDIvol and 353, 485, 592 and 1073 mGy cm for DLP. This study shows that the optimisation of paediatric CT procedures should be a priority, especially within regional hospitals. The implementation of corrective actions will take place after the initial DRLs. These actions, including recommendations and guidelines to good practice, should be a joint effort of all stakeholders, including health authorities, the radiation protection regulator, professional societies and universities. [ABSTRACT FROM AUTHOR]

The current approach in the system of protection, and the way in which it is implemented in regulation and practical application, has resulted in the allocation of significant and disproportionate societal resources to reduce relatively low-level exposures to even lower levels. The resulting exposure levels are often a fraction of the basic natural background level, and in particular are comparable to, or often significantly less than, the variability of natural background exposures due to individual decision-making, which the system of protection deems acceptable. There are arguments for a wider approach to decision-making at such low doses, recognising the uncertainties in radiation risk estimation and acknowledging the context that all human life takes place in a variable natural background radiation which generally dominates these lower dose exposures. Recommendations are presented for improvements in how decisions are made in controlling low doses. [ABSTRACT FROM AUTHOR]

A coherent and overarching framework for health protection from non-ionising radiation (NIR) does not currently exist. Instead, many governments maintain different compliance needs targeting only some NIR exposure situations. An international framework developed by the World Health Organization would promote a globally consistent approach for the protection of people from NIR. Designed based on decades of practical experience the framework provides guidance on establishing clear national health and safety objectives and how they should be achieved. It supports multisectoral action and engagement by providing a common language and systematic approach for managing NIR. The framework should allow governments to respond to policy challenges on how to achieve effective protection of people, especially in a world that is rapidly deploying new NIR technologies. In this paper the concepts and key features are presented that underpin the framework for NIR protection, including examples of implementation. [ABSTRACT FROM AUTHOR]

At the Belgian Nuclear Research Centre (SCK CEN) more than 850 employees advance the peaceful applications of ionising radiation through research, services and education and training. Several initiatives are taken to guarantee a safe working environment, one of them being a compulsory introductory safety training for all new employees, followed by refresher courses. With the objective to increase the flexibility for the participants and to optimise the teaching time of lecturers, the training format is adapted from face-to-face training to blended learning in which a significant amount of online learning is introduced. To appraise the perception and effectiveness of the original face-to-face training and the newly developed e-learning modules, and to compare both, information is gathered on two levels. Firstly, to monitor the perception of the participants regarding the face-to-face and e-learning formats an online questionnaire was launched. Secondly to evaluate the knowledge gain (difference between pre- and post-test results), the participants were requested to answer the same set of technical/scientific questions before and after the training. Results of the perception study show that the e-learning format was well received by the learners. For both learning formats an overall knowledge gain was noticed. The highest knowledge gain was noticed for the e-learning format. The results on perception and effectivity of the e-learning format confirm the further use of this format. [ABSTRACT FROM AUTHOR]

The 2013/59/Euratom Directive reduced the occupational exposure limits for the lens. Since it has become crucial to estimate the dose absorbed by the lens, we have studied the individual variability of exposed workers’ ocular conformations with respect to the data estimated from their personal dosimetry. The anterior eye conformations of 45 exposed workers were acquired using Scheimpflug imaging and classified according to their sight conditions (emmetropia, myopia or hypermetropia). Three eye models were computed, with two lens reconstructions, and implemented in an interventional radiology scenario using Monte Carlo code. The models were dosimetrically analysed by simulating setup A, a theoretical monoenergetic and isotropic photon source (10â€"150 keV) and setup B, a more realistic interventional setting with an angiographic x-ray unit (50, 75, 100 kV peak). Scheimpflug imaging provided an average anterior chamber depth of (6.4 ± 0.5) mm and a lens depth of (3.9 ± 0.3) mm, together with a reconstructed equatorial lens length of (7.1â€"10.1) mm. Using these data for model reconstruction, dose coefficients (DCs) were simulated for all ocular structures. Regardless of the eye model used, the DCs showed a similar trend with radiation energy, which highlighted that for the same energy and setup, no significant dependence on ocular morphology and workers’ visual conditions was observed. The maximum difference obtained did not exceed 1% for all eye models or structures analysed. Therefore, the individual variabilities of worker ocular anatomy do not require any additional correction, compared to the personal dosimetry data measured with a dedicated lens dosimeter. To estimate the dose absorbed by the other eye structures, it is, instead, essential to know the spectrum of the source that has generated the irradiation, since there are differences between monoenergetic sources and more realistic angiographic units. [ABSTRACT FROM AUTHOR]

The International Commission on Radiation Units and Measurements (ICRU) Report Number 95 (2020 Operational quantities for external radiation exposure ICRU Rep. 95 J. ICRU 20) recommends new definitions ffor operational quantities as estimators of the International Commission on Radiological Protection radiation protection quantities. As part of this report, dose coefficients for neutron fluences are included for energies from 10âˆ'9â€"50 MeV. For lens of the eye dosimetry, several changes in the ICRU recommended quantities are of particular interest. First, an updated eye model is used that includes segmentation of the sensitive lens region. In addition, the use of absorbed dose instead of dose equivalent has been selected as the appropriate operational quantity since deterministic (i.e. non-stochastic) effects are of primary importance for the lens of the eye. The ICRU report also addresses computational parameters, such as absorbed dose tally volumes, depths, source areas and source rotational angles. In this work, neutron dose coefficients calculated for the lens of the eye in support of the ICRU report are presented. Dose coefficients for mono-energetic neutrons and reference neutron spectra are presented. The source is a parallel beam, and the mono-energetic dose coefficients are provided for rotational angles with respect to the front face of the head ranging from 0°â€"90°. In addition, monoenergetic dose coefficients for the parallel beam incident on the back of the head (180°) and for a rotational source geometry where the head is irradiated from all angles are reported. For all scenarios, absorbed doses to the complete lens and the sensitive volume of each eye were calculated. Eye lens absorbed dose coefficients, D p,slab(3,0)/Φ, were also calculated in an ICRU tissue slab phantom at a depth of 3 mm for a parallel beam irradiating the slab perpendicular to the front face, and these results are compared to the values determined using the eye phantom. [ABSTRACT FROM AUTHOR]

An essential part of a protection strategy for radiological emergencies is the development of national dose criteria and of operational intervention levels (OILs) to decide about protective measures for all ten scenarios Germany is preparing. For the process of planning and implementing such protection strategies as required by the German Radiation Protection Law the Federal Ministry BMU has commissioned the German Radiation Protection Commission (SSK) to recommend dose criteria and OILs for emergency response measures. OILs link a chosen dose criterion for a protective action with a suitable measurement of the contamination situation such as ambient dose rate (μSv h−1), contamination level on surfaces (Bq cm−2) or activity content (Bq g−1, Bq cm−3). This link should adequately model the exposure of persons during a defined exposure period (e.g. seven days, one year) caused by the measured contamination. Dose calculations to quantify OILs should apply assumptions and parameter values that are in tendency realistic and not unduly conservative. OILs have been developed for the following emergency response actions based on radiation measurements: • Sheltering on the basis of dose rate (μSv h−1) and contamination level(Bq cm−2). • Evacuation on the basis of dose rate (μSv h−1) and contamination level(Bq cm−2). • Establishing a radiological hazard area to implement access andcontamination control on the basis of dose rate (μSv h−1) and contaminationlevel (Bq cm−2). • Contamination control and possibly decontamination of persons and objects(items, goods, vehicles, etc) based on contamination level (Bq cm−2). • A set of precautionary early actions: warning the population not toconsume freshly contaminated food and agricultural measures to reducefood contamination based on dose rate (μSv h−1). • Application of maximum permitted levels of radioactive contamination offood and feed (Bq kg−1) according to Euratom Regulation. [ABSTRACT FROM AUTHOR]

Over the last 10 years there have been increasing concerns raised about a potential skills gap in the field of radiation protection (RP). Noting these concerns in 2019, the Society for Radiological Protection, the UK's Chartered Professional Body, launched a study to determine the RP demand in the UK going forward along with the capacity of the profession. The initial results show that over 50% of the SRP membership retires in the next 10−15 years, coupled with an increase in RP demand across the nuclear fuel cycle, medical sector and advancement of new technologies or applications requiring RP advice. This provides strong evidence supporting the concerns of a future skills gap. This paper presents a framework highlighting three core objectives that need to be met to resolve the skills gap. A review of the existing initiatives being undertaken by the Society of Radiological Protection to meet these objectives is included, identifying both areas of good practice and areas for further work and development. A key theme in tackling this challenge has been identified as the need to foster greater collaboration between RP professionals, and organizations both within the UK and abroad, such as IRPA, national societies, employers, academia and industry. This brings a unique opportunity to direct efforts and resources toward a common goal, allowing the sharing of good practice, whilst reducing the strain and burden on any one organization. Another key output of the review was the need to embrace new and innovative solutions to developing our profession and importantly inspiring and communicating into the future of the profession. [ABSTRACT FROM AUTHOR]

The International Radiation Protection Association, IRPA, promotes the worldwide enhancement of professional competence, radiation protection (RP) culture and practice by providing benchmarks of good practice, as well as encouraging the application of the highest standards of professional conduct, skills and knowledge for the benefit of individuals and society. Enhancing public understanding of radiation and risk is highlighted by experiences from past emergencies, including the accident at Tokyo Electric Power Company's (TEPCO) Fukushima Daiichi Nuclear Power Plant in 2011 and the following post-disaster recovery, as one of the most important challenges, and this challenge is common across almost all public interfaces regarding radiation and risk. To this end IRPA has been continuing a Task Group activity for Public Understanding since 2013. After a series of workshops in various regions of the world, the IRPA draft guidance was developed and issued for consultation of the Associate Societies in 2019. Through these processes, IRPA received a lot of helpful comments and suggestions. IRPA finally published 'Practical Guidance for Engagement with the Public on Radiation and Risk' on the IRPA website in October 2020. The objective of the guidance is two-fold. Firstly, it is to enthuse all of us in our profession to become more active public advocates for RP. Secondly, it is to provide information, experiences and techniques to help us to become more effective and comfortable in this challenging task. This paper provides a key summary of the published IRPA guidance. [ABSTRACT FROM AUTHOR]

A special session was held in the International Radiation Protection Association (IRPA15) Congress to address the particular challenges facing developing countries regarding radiation protection infrastructure. The objective was to identify and share the key challenges facing developing countries regarding the ability to introduce and establish effective radiation protection programmes. The experiences of key international organisations (International Atomic Energy Agency, Pan American Health Organisation and World Health Organisation) that have support programmes were discussed, along with a perspective from several countries with developing programmes. The key common challenges include: governmental commitment at senior levels, with provision of the necessary resources: establishment of an independent regulatory body and related infrastructure: appropriate numbers of qualified staff in all necessary fields, including their education and training: supporting physical infrastructure, such as dosimetry and measurement equipment including calibration laboratories. In addressing these challenges the importance of support from the key international organisations was emphasised. More emphasis should be given to the application of the graded approach. The establishment of support networks at a national or regional level that allow for the sharing of experiences and resources, and that support the wellbeing of isolated professionals, is also crucial. In this aspect the support from wider professional bodies such as IRPA and established national radiation protection societies can also play a key role. [ABSTRACT FROM AUTHOR]

Large accelerator facilities for scientific research and particle accelerators for radiotherapy have been constructed in Korea. The environments requiring radiological protection procedures have changed substantially and the legal requirements have also increased. However, the same regulatory criteria that are applied to small radiation-generating devices also apply to large accelerator facilities. This study evaluates an approach that uses new criteria based on radiological risk to classify different types of large accelerator facilities. To inform this study, regulations and licensing procedures adopted in various countries were reviewed. The radiological risks from different types of particle accelerators and different types of accelerated particles were investigated in relation to current and planned large accelerators in Korea. The investigation was based on neutron yield and induced radioactivity calculations undertaken using the Monte-Carlo code FLUKA. Based on this analysis, we propose two categories for large accelerator facilities. In the process of the facility construction through to getting an operation permit, we also propose a graded approach, which would require changes in the Korean Nuclear Safety Act. A two-step licensing procedure with a prior review and a final permit for accelerator operation is very practical and conservative in the view of radiation protection. The review process for the revision of the Nuclear Safety Act is currently in progress and a major aspect of this revision reflects the results of this study. [ABSTRACT FROM AUTHOR]

There are many aspects of radiological protection in medicine that are different from other areas of activity using ionising radiation. In this paper, the author presents and justify some of these differences and highlight the reasons for and benefits of this consideration for the medical field. It is important to understand the differences as we are all likely to be patients at some point in our lives and be exposed to ionising radiation for imaging procedures several times and, in some cases, for therapeutic indications. The work done by the International Commission on Radiological Protection and other international organisations to produce and recommend a consistent system of radiological protection in medicine for the safe use of ionising radiation in medical practices must be highlighted. We should understand why we do not apply dose limits and dose constraints to patients, as well as why we have three levels of justification when considering the use of ionising radiation for patients. We highlight the relevance of personalised radiation protection in parallel to personalised medical practice, and the importance of an integrated approach for occupational and patient protection, especially for interventional procedures. We also cover the differences between patients and volunteers in biomedical research, the importance of radiation safety in quality assurance programmes (including the consideration of unintended and accidental exposures) for some clinical practices, and the relevance of education and training in radiological protection for medical and health professionals and information on radiation risks for patients. Finally, the ethical issues with regard to the safe use of ionising radiation in medicine and the impact of new technology will be addressed. [ABSTRACT FROM AUTHOR]

The new German Radiation Protection Act (StrlSchG) of 31 December 2018 established a reference value of 300 Bq m−3 for the annual average radon activity concentration in buildings with recreation and living rooms, as well as in workplaces. It is expected that the reference value will be exceeded in a vast number of buildings throughout Germany and that radon protection measures will become indispensable. A simple and inexpensive radon protection measure for existing buildings is ventilation. In the scope of a joint project, ventilation systems with zone control and heat recovery are to be extended by the control parameter radon activity concentration. A highly sensitive, miniaturized radon monitor will be developed for this purpose, which can be integrated wirelessly into ventilation systems. Radon measurements were carried out in 13 apartments of an unoccupied heated apartment block in Germany over a period of three weeks in the wintertime. High radon activity concentrations were found on all three floors. The maximum values were 14000 Bq m−3 on the first floor, 6000 Bq m−3 on the second floor, and 2000 Bq m−3 on the third floor. Ventilation experiments were carried out in an apartment with high radon activity concentration. Two decentralized ventilation systems with heat recovery were installed in each of the two opposite outside walls. The controlling device of the system was activated wirelessly depending on the radon activity concentration. The radon activity concentration was reduced from 8000 Bq m−3 to 800 Bq m−3 in a first experiment in the living room. [ABSTRACT FROM AUTHOR]

As we progress towards more diverse, equitable, and inclusive communities, workplaces, and organizations in radiation protection (RP), we begin to consider the experiences of our fellow radiation protectionists in parallel with our own. This is to identify, and ideally take down, barriers to pursuing a fulfilling career and positive professional relationships. Recognition and active consideration of differential experiences and needs will help promote both personal and community level success. Over the past few years there have been concerted efforts within the RP community to consider and promote the participation of women. An example outcome of this effort is that we are seeing more women assuming prominent leadership positions in our community. As we celebrate the progress made towards equity, specifically with respect to women, it is important to consider that other factors such as race and gender identity can present their own barriers. Those at the intersection of these or other identities often find themselves in the so-called 'double bind' of more pronounced, or stacking, barriers to success. This paper briefly highlights the need for considering the intersectionality of race and gender in the promotion of equity for all women. [ABSTRACT FROM AUTHOR]

Dose equivalent limits for single organs are recommended by the ICRP (International Commission for the Radiological Protection publication 103). These limits do not lend themselves to be measured. They are assessed by convoluting conversion factors with particle fluences. The Fluence-to-Dose conversion factors are tabulated in the ICRP literature. They allow assessing the organ dose of interest using numerical simulations. In particular, the literature lacks the knowledge of local skin equivalent dose (LSD) coefficients for neutrons. In this article, we compute such values for neutron energies ranging from 1 meV to 15 MeV. We use FLUKA, MCNP and GEANT4 Radiation transport Monte-Carlo simulation codes to perform the calculations. A comparison between these three codes is performed. These calculated values are important for radiation protection studies and radiotherapy applications. [ABSTRACT FROM AUTHOR]

Collimating apertures are used in proton therapy to laterally conform treatment fields to the target volume. While this is a standard technique in passive spreading treatment heads, patient-specific apertures can supplement pencil-beam scanning (PBS) techniques to sharpen the lateral dose fall-off. A radiation protection issue is that proton-induced nuclear reactions can lead to the formation of radionuclides in the apertures. In the experiments of the current study, cylindrical, thick brass targets were irradiated with quasi-monoenergetic proton fields of 100.0 MeV and of 226.7 MeV in PBS mode. The radioactivation of these two brass samples was characterised with a low-level gamma-ray spectrometer. The activation products were scored in a Monte Carlo simulation, too, and compared with the experimental activities. For the high-energy field, 63Zn, 60Cu, and 61Cu were the most important short-lived isotopes regarding the measured specific activity. After irradiation with the 100.0 MeV field, 62Cu, 63Zn, and 60Cu had the highest activity. Regarding long-lived isotopes, which determine the storage time of the used apertures, the isotopes 57Co, 65Zn, 54Mn, 56Co had the largest contribution to the activity. The relative difference of activities between simulation and experiment was typically between 10%–20% for short-lived nuclides and were up to a factor of five larger for long-lived nuclides. Summarising experiments and simulations for both incident proton energies, 62Cu was the most important detected residual nucleus regardless if specific activity or equivalent dose is considered. [ABSTRACT FROM AUTHOR]

The objective of this work was to make an intercultural adaptation and provide a Spanish translation and psychometric evaluation of the original English version of the Healthcare Professional Knowledge of Radiation Protection (HPKRP) scale. The Spanish translation was carried out following international guidelines for the process of cross-cultural adaptation of self-report measures. A cross-sectional design study was carried out. One hundred and thirty-eight nurses from four different hospitals in Barcelona (Spain) completed the Spanish version of the scale. The total score of the scale was calculated. The Pearson correlation coefficient (PCC) was used to evaluate a possible correlation between score and years of experience. A t-test for independent samples was used to evaluate significant differences between different groups. Cronbach's alpha, the corrected item–total correlation coefficient and the test–retest coefficient were used to determine internal consistency. The exploratory factor and parallel analysis were also calculated. All statistical tests were carried out with a level of significance α = 0.05. The mean scale score was poor among Spanish nurses. The PCC between total score and years of experience showed a non-significant correlation (p > 0.05). No differences were found between nurses who worked in radiation-exposed units and those who worked in units without radiation exposure (p > 0.05). A Cronbach α of 0.98 was obtained for the items of the scale. The corrected item–total correlation range was 0.5–0.8. The test–retest correlation coefficient was 0.9. The exploratory analysis factor showed a single factorial structure which explained 60.86% of the variance. The new scale translated into Spanish (Sp-HPKRP) could be used to evaluate the degree of knowledge about radiological protection. [ABSTRACT FROM AUTHOR]

Internal dose assessment intercomparison exercises are useful tools: to verify the performance of an internal dosimetry service; to promote the harmonisation of dose assessments; and to identify weaknesses where further improvements are necessary. However, no such international intercomparisons have been performed for more than ten years. In the period May 2014–May 2016, the 'Technical Recommendations for Monitoring Individuals for Occupational Intakes of Radionuclides' were developed on the initiative of the European Commission, and later published within the EC Radiation Protection series, as RP188. In 2017 the Working Group 'Internal Dosimetry' of the European Radiation Dosimetry Group (EURADOS) organised a new intercomparison action, named ICIDOSE 2017, with the main aim of testing the practical applicability of these technical recommendations (RP188). Four case studies were proposed to participants: an artificially created case of inhalation of 60Co to simulate a simple special monitoring case; a real case of inhalation of 125I, with simple routine monitoring; a real and more complex case of incorporation of 234+235+238U, featuring both confirmatory and special monitoring; and a complex real case of an accidental incorporation of 241Am, including multiple administrations of diethylenetriamine pentaacetic acid (DTPA). Results were received from 66 participants from 26 countries; these were compared to reference or recommended solutions, developed for each case based on the application of RP188. In cases 1, 2 and 4 only a small number of results were identified as outliers, with the spread of all the results, expressed as the geometric standard deviation (GSD) of the values, assessed as 1.07, 1.04 and 1.43, respectively. This observed spread of the submitted results was improved from those obtained from similar cases in previous intercomparison exercises, showing that the availability of RP188 contributes to the harmonisation of the internal dose assessment process. There was a much wider spread of results for the uranium case: this case was characterised by an absence of any prior knowledge of the exposure scenario, and participants assumed a range of different exposure pathways and patterns. [ABSTRACT FROM AUTHOR]

Low doses of radiation are used in diagnostic tests such as X-rays or CT exams. A Linear No Threshold model (LNT) is used to assess radiation risk. According to this model, risk decreases linearly with a decreasing dose, with no lower threshold. However, there is no definitive evidence to support risk at very low doses and the model relies on extrapolation to estimate risk at doses below a few 10 s mSv. The simplicity of the LNT model can disguise the more complex questions that arise when the facts are uncertain. There is a considerable debate over how best to interpret and communicate these risks for low dose exposures. This paper criticises arguments on both sides of this debate. In discussing the case for asserting risk we argue that it is only as a scientific model that LNT should be used to make predictions that can be tested. Taking the further step of using these calculations to state how many cancers are caused by the use of X-rays requires a strong scientific model and the disputed status of the LNT model and the consequent uncertainty as to whether low dose radiation definitely causes cancer, is the major obstacle to making these types of claims. In discussing arguments which tend to dismiss risk, we identify the hidden premises needed to support these claims. Differences between a prudent model and a scientific model are considered. A 'reductio ad absurdum' objection, and fallacies of ambiguity, where 'insignificant risk' may be confused with 'inconsequential risk', are also discussed. Disagreement over the interpretation of risk has the potential to disrupt the optimum use of medical imaging technology. While communication of risk need not address the underlying philosophical complexities, advice from the radiation protection community must be rooted in an awareness of these issues if inconsistencies are to be avoided. [ABSTRACT FROM AUTHOR]

Although radiation protection is challenged by many uncertainties, there is no systematic study investigating the definitions and types of these uncertainties. To address this gap, in this paper we offer a scoping review to comprehensively analyse, for the first time, peer-reviewed scientific articles (n = 33) related to uncertainties in the following radiation exposure situations: nuclear emergencies, decommissioning of nuclear/radiological installations and long-term radiological exposure situations (e.g. naturally occurring radioactive materials). The results suggest that firstly, there is no agreement regarding definitions of uncertainty, which is mainly defined based on its sources, types or categories rather than by its meaning. Secondly, different actors are faced with different types of uncertainties. Uncertainties of the scientific community are mostly data and methodology-driven (e.g. dose-response relationships), those of the decision-makers are related to the likely consequences of decision options and public reactions, while laypeople's uncertainties are mainly related to the trustworthiness of experts or the emotional potential of specific risk exposures. Furthermore, the majority of articles focus on the uncertainties of the scientific community, while those of the information receivers (i.e. decision-makers and laypeople) receive much less consideration. Finally, there was no difference in types of uncertainties across the different risk-related study areas analysed (radiation versus other risks). Based on these findings, we provide some preliminary recommendations regarding research on uncertainty related to radiation protection, as well as communication practices. [ABSTRACT FROM AUTHOR]

Routine monitoring is an important element of any occupational radiation protection programme to be able to determine how effective this protection is in practice. As well as providing information on normal operational conditions and routine worker dose uptakes, these programmes are also required to be able to detect the occurrence of abnormal or unexpected exposures to radionuclides, where these risks are deemed to be present in the workplace. Various monitoring techniques and methods are available and can be applied to the direct monitoring of workers or of the workplace. For many of the less radio-toxic radionuclides simple monitoring programmes are often more than sufficient to demonstrate compliance with operational and regulatory controls; however, multiple programmes, operated in parallel, are often required for the more radio-toxic radionuclides—e.g. Plutonium and americium—to be able to provide assurance that the potential risks of exposure are reliably and adequately controlled. When a potential exposure event is detected then further investigations are instigated to confirm whether an intake has occurred and to estimate the resultant dose. This paper presents an empirical review of the records of all such investigations over an eighteen-year period at the Harwell site, Oxfordshire, UK. The purposes of this review were to determine the relative effectiveness of different monitoring methods in being able to detect potential exposure events; and how efficient each method was in detecting potential exposures which, following investigation, were confirmed as real intakes. The analyses revealed that routine faecal sampling provided the better performance characteristics in terms of combined effectiveness and efficiency; and that the ability to detect potential exposures (at levels of up to 6 mSv) in the absence of any routine monitoring programme was limited. There was a very low incidence of potential exposures being detected by more than one monitoring technique, which emphasises the importance of operating multiple monitoring methods in order to optimise the probability and confidence of detecting potential exposures. [ABSTRACT FROM AUTHOR]

Emergency preparedness and response (EP&R) to radiological or nuclear accidents depends on many different stakeholder groups: nuclear and radiological regulators and authorities; institutions and ministries concerned by health, environment and consumption; first-line responders including the police, military, firefighters and health workers; as well as local authorities and nuclear industries. Stakeholders also include the general public, such as people living near NPPs8 or affected by previous nuclear or radiological accidents and incidents. Teachers and journalists, bloggers and other social media figures would play a key role in effective dissemination of knowledge and information. NGOs9 or civil associations/societies can also be involved in radiation monitoring and protection. The present study describes the role of different research institutions (such as CIEMAT10, UPM11 and ISGlobal12) and of the Spanish Society of Radiological Protection (SEPR) in bringing together the above-listed stakeholders in Spain to discuss EP&R and identify benefits and challenges of working together. Stakeholder opinions on EP&R, collected mainly in the framework of several European-funded projects, are provided. Remaining barriers and examples of good practices in radiation protection are discussed, as well as recommendations for improving nuclear and radiological emergency preparedness in Spain. The conclusions may be useful for other countries. [ABSTRACT FROM AUTHOR]

Communicating radiation risk is an important part of radiation protection. However, achieving effective risk communication is challenging given the negative public perception of radiation and conflicting views presented by both the media and social media. Noting the importance of building capacity amongst radiation protection professionals to communicate radiation risk effectively, the Society for Radiological Protection (SRP) ran a half-day workshop at its Annual Conference on the 22nd May 2019 in Scarborough Spa, UK. A number of key factors were identified that should be considered when communicating with the public, post a nuclear or radiological incident, communicating with government and local authorities, and communicating with the public as part of public outreach. The following memorandum provides a summary of the points presented and discussed. It also outlines proposed future activities of the SRP, focused on further developing the communications aspect of radiation professionals' practice. [ABSTRACT FROM AUTHOR]

We conducted a survey of doctors working in the cardiac catheterisation laboratories in Africa on their knowledge, attitude and practice with respect to radiation protection. Of seventy-two respondents contacted, 61 (84.7%) completed the questionnaire. Twenty-eight, (45.9%) were younger than 45 years. Thirty-seven, (60.6%) had less than 10 years of experience in the laboratory. Only 28 (45.9%) had undertaken radiation protection training. Fifty-eight, (95.1%) consistently used lead aprons. Forty-seven, (77%) reported consistently using thyroid shields. Ten (16.4%) consistently used radiation protection eyeglasses, whilst 36 (59%) never used them. Thermoluminescent Dosimeter badges were consistently used in 23 (37.7%). Forty-two, (68.9%) reported having ceiling mounted lead/acrylic shields. Level of radiation exposure in the most recent one year was ≤2 mSv in 14, between 2 and 20 mSv in 8 and between 20 and 30 mSv in 2, whilst 33 did not know their dose readings. The use of basic radiation protection tools as well as the knowledge and measurement of radiation exposure among interventional cardiologists working in Africa is low. The unavailability of some of the protective tools and a knowledge gap in terms of radiation protection and monitoring of self-exposure were some of the reasons for suboptimal self-protection against ionising radiation among our respondents. We suggest that initiatives be taken by all stakeholders to train this group of medical professionals in basic radiation protection to avoid unnecessary exposure to themselves, co-workers and patients. [ABSTRACT FROM AUTHOR]

Purpose: Recently new mobile systems for dispensing positron emitters have been produced, designed to guarantee dispensing cycles in an aseptic environment. The aim of the present work was to assess the advantage of one of these systems in radiation protection of operators in clinical settings. Methods: Recently, in our centre the new self-dispensing system named KARL100 by Tema Sinergie was adopted for 18F-FDG radiopharmaceuticals. The system is associated with an automatic Rad-inject infuser. The system that was previously used was a fixed isolator NMC DSI (Tema Sinergie), equipped with a μDDS-An activity fractioning system, together with a pneumatic post for the syringe delivery. The dosimetric evaluations on both systems were carried out through environmental measurements with an ionisation chamber and with the use of personal dosimeters. Results: The operations of preparation and administration of 18F-FDG dose to the patient, with the use of Karl100 + RadInject, involve exposures much lower than those obtained by the fixed isolator. The average body exposure of the technician was reduced by 31%, and for the physician by 77%. On the extremities, the equivalent dose to the hands of the technician was reduced by 78%, and for the physician by 96%. Also the additional dosimeters worn by the technician confirmed the estimated environmental assessments. Conclusions: The exposures of the working personnel were significantly reduced with the introduction of the new KARL100 system. [ABSTRACT FROM AUTHOR]

This report was commissioned by the IRPA President to provide an assessment of the impact on members of IRPA Associate Societies of the introduction of ICRP recommendations for a reduced dose limit for the lens of the eye.The report summarises current practice and considers possible changes that may be required.Recommendations for further collaboration, clarification and changes to working practices are suggested. Approved by the IRPA Executive Council in July 2013 [ABSTRACT FROM AUTHOR]

Radiation sources have being widely used in industrial applications, but their inappropriate use presents a large potential for hazards to human health and the environment. These hazards can be minimised by development of specific radiation protection rules and adequate procedures for the handling, use and storage of radiation sources, which should be established in a national normative framework. Recently, due to discovery of new oil and gas reservoirs on the Brazilian continental shelf, especially in deep water and the pre-salt layerAn aggregation of rocks located offshore of a large portion of the Brazilian coast, with the potential to accumulate oil. This layer was called pre-salt because it forms a rock interval that ranges under an extensive layer of salt which, at certain areas of the coast, can be as much as 2000 m thick. The distance between the surface of the sea and the oil reservoirs under the salt layer can be as much as 7000 m., there has been a large and rapid increase in the use of radiation sources for well logging. Generic radiation protection regulations have been used for licensing the use of radiation sources for well logging, but these are not comprehensive or technically suitable for this purpose. Therefore it is necessary to establish specific Brazilian safety regulations for this purpose. In this work, an assessment is presented of the relevant radiation protection aspects of nuclear well logging not covered by generic regulations, with the aim of contributing to the future development of specific safety regulations for the licensing of radioactive facilities for oil and gas well logging in Brazil. The conclusions of this work relate to four areas, which include the specific requirements to control (1) radiation sources, (2) radiation survey meters and (3) access to radiation workplaces and (4) to control and identify the workers who are occupationally exposed. [ABSTRACT FROM AUTHOR]

The article presents abstracts on topics related to radiological protection which include the issues during and after the Fukushima nuclear reactor accident in Japan, the estimation of health risks from ionising radiation exposure and the risk associated with low dose radiation exposure.

The purpose of this study is the development of paediatric reference phantoms for newborn and 1-year-old infants to be used for the calculation of organ and tissue equivalent doses in radiation protection. The study proposes a method for developing anatomically highly sophisticated paediatric phantoms without using medical images. The newborn and 1-year-old hermaphrodite phantoms presented here were developed using three-dimensional (3D) modelling software applied to anatomical information taken from atlases, textbooks and images provided by the Department of Anatomy of the Federal University of Pernambuco, Brazil. The method uses polygon mesh surfaces to model body contours, the shape of organs as well as their positions and orientations in the human body. Organ and tissue masses agree with corresponding data given by the International Commission on Radiological Protection for newborn and 1-year-old reference children. Bones were segmented into cortical bone, spongiosa, medullary marrow and cartilage to allow for the use of μCT images of trabecular bone for skeletal dosimetry. Anatomical results show 3D images of the phantoms' surfaces, organs and skeletons, as well as tables with organ and tissue masses or skeletal tissue volumes. Dosimetric results present comparisons of organ and tissue absorbed doses or specific absorbed fractions between the newborn and 1-year-old phantoms and corresponding data for other paediatric stylised or voxel phantoms. Most differences were found to be below 10%. [ABSTRACT FROM AUTHOR]

Measurements of doses to hands, legs and eyes are reported for operators in four different hospitals performing vertebroplasty or kyphoplasty. The results confirm that occupational doses can be high for interventional spine procedures. Extremity and eye lens doses were measured with thermoluminescent dosimeters positioned on the ring fingers, wrists, legs and near the eyes of interventional radiologists and neurosurgeons, over a period of 15 months. Doses were generally larger on the left side for all positions monitored. The median dose to the left finger was 225 μSv per procedure, although a maximum of 7.3 mSv was found. The median dose to the right finger was 118 μSv, but with an even higher maximum of 7.7 mSv. A median left eye dose of 34 μSv (maximum 836 μSv) was found, while the legs received the lowest doses with a median of 13 μSv (maximum 332 μSv) to the left leg. Annual dose to the hand assessed by the cumulated doses almost reached the annual dose limit of 500 mSv, while annual dose to the eyes exceeded the eye lens dose limit of 20 mSv yr-1. Different x-ray systems and radiation protection measures were tested, like the use of lead gloves and glasses, tweezers, cement delivery systems and a magnetic navigation system. These measurements showed that doses can be significantly reduced. The use of lead glasses is strongly recommended for protection of the eyes. [ABSTRACT FROM AUTHOR]

The fourth workshop of the Multidisciplinary European Low Dose Initiative (MELODI) was organised by STUK-Radiation and Nuclear Safety Authority of Finland. It took place from 12 to 14 September 2012 in Helsinki, Finland. The meeting was attended by 179 scientists and professionals engaged in radiation research and radiation protection. We summarise the major scientific findings of the workshop and the recommendations for updating the MELODI Strategic Research Agenda and Road Map for future low dose research activities. [ABSTRACT FROM AUTHOR]

The information for the present discussion on the uncertainties associated with estimation of radiation risks and probability of disease causation was assembled for the recently published NCRP Report No. 171 on this topic. This memorandum provides a timely overview of the topic, given that quantitative uncertainty analysis is the state of the art in health risk assessment and given its potential importance to developments in radiation protection. Over the past decade the increasing volume of epidemiology data and the supporting radiobiology findings have aided in the reduction of uncertainty in the risk estimates derived. However, it is equally apparent that there remain significant uncertainties related to dose assessment, low dose and low dose-rate extrapolation approaches (e.g. the selection of an appropriate dose and dose-rate effectiveness factor), the biological effectiveness where considerations of the health effects of high-LET and lower-energy low-LET radiations are required and the transfer of risks from a population for which health effects data are available to one for which such data are not available. The impact of radiation on human health has focused in recent years on cancer, although there has been a decided increase in the data for noncancer effects together with more reliable estimates of the risk following radiation exposure, even at relatively low doses (notably for cataracts and cardiovascular disease). New approaches for the estimation of hereditary risk have been developed with the use of human data whenever feasible, although the current estimates of heritable radiation effects still are based on mouse data because of an absence of effects in human studies. Uncertainties associated with estimation of these different types of health effects are discussed in a qualitative and semi-quantitative manner as appropriate. The way forward would seem to require additional epidemiological studies, especially studies of low dose and low dose-rate occupational and perhaps environmental exposures and for exposures to x rays and high-LET radiations used in medicine. The development of models for more reliably combining the epidemiology data with experimental laboratory animal and cellular data can enhance the overall risk assessment approach by providing biologically refined data to strengthen the estimation of effects at low doses as opposed to the sole use of mathematical models of epidemiological data that are primarily driven by medium/high doses. NASA's approach to radiation protection for astronauts, although a unique occupational group, indicates the possible applicability of estimates of risk and their uncertainty in a broader context for developing recommendations on: (1) dose limits for occupational exposure and exposure of members of the public; (2) criteria to limit exposures of workers and members of the public to radon and its short-lived decay products; and (3) the dosimetric quantity (effective dose) used in radiation protection. [ABSTRACT FROM AUTHOR]

The article presents abstracts on topics related to radiological protection including the artificial radionuclides in the Irish Sea, the radiation risk of the children of atomic bomb survivors and the radiographic protocols in pediatric interventional cardiology.

Information about the 14th European As Low As Reasonably Achieved (ALARA) Network Workshop held in Dublin, Ireland on September 4-6, 2012 is presented. Topics include the factors that must be considered in determining radiation dose reference levels, the challenges and practicalities related to ALARA, and stakeholder engagement. The event was graced by 66 individuals from 17 different countries.

This paper presents the response of the Health Protection Agency (HPA) to the 2011 statement from the International Commission on Radiological Protection (ICRP) on tissue reactions and recommendation of a reduced dose limit for the lens of the eye. The response takes the form of a brief review of the most recent epidemiological and mechanistic evidence. This is presented together with a discussion of dose limits in the context of the related risk and the current status of eye dosimetry, which is relevant for implementation of the limits. It is concluded that although further work is desirable to quantify better the risk at low doses and following protracted exposures, along with research into the mechanistic basis for radiation cataractogenesis to inform selection of risk projection models, the HPA endorses the conclusion reached by the ICRP in their 2011 statement that the equivalent dose limit for the lens of the eye should be reduced from 150 to 20 mSv per year, averaged over a five year period, with no year's dose exceeding 50 mSv. [ABSTRACT FROM AUTHOR]

The IRPA13 Congress took place from 14-18 May 2012 in Glasgow, Scotland, UK, and was attended by almost 1500 radiological protection professionals. The scientific programme of the Congress was designed to capture a snapshot of the profession's views of the current state of knowledge, and of the challenges seen for the coming years. This paper provides a summary of these results of the Congress in twelve key scientific areas that served as the structural backbone of IRPA13. [ABSTRACT FROM AUTHOR]

This paper describes research aimed at improving regulatory supervision of radiation safety during work associated with the management of spent nuclear fuel and radioactive waste at legacy sites in northwest Russia through timely identification of employees presenting unfavourable human factor risk characteristics. The legacy sites of interest include sites of temporary storage now operated by SevRAO on behalf of Rosatom. The sites were previously operational bases for servicing nuclear powered submarines and are now subject to major remediation activities. These activities include hazardous operations for recovery of spent nuclear fuel and radioactive waste from sub-optimal storage conditions. The paper describes the results of analysis of methods, procedures, techniques and informational issues leading to the development of an expert-diagnostic information system for monitoring of workers involved in carrying out the most hazardous operations. The system serves as a tool for human factor and professional reliability risk monitoring and has been tested in practical working environments and implemented as part of regulatory supervision. The work has been carried out by the Burnasyan Federal Medical Biophysical Center, within the framework of the regulatory cooperation programme between the Federal Medical-Biological Agency of Russia and the Norwegian Radiation Protection Authority. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which include radiation risk assessment, reliability of dose coefficients for inhaled and ingested radionuclides and chromosomal aberrations.

Exposure of the general public to electromagnetic radiation originating from randomly selected GSM/WCDMA base stations in Riyadh, Kingdom of Saudi Arabia has been assessed in the context of the International Commission on Non-Ionising Radiation Protection (ICNIRP) guidelines. The purpose of the measurement was to record the maximum power density of signals to estimate possible worst case exposure at each measurement location. These power density measurements were carried out at 60 mobile base stations located in different regions of the city. For each of these sites, three sectors were operational, yielding a total of 180 sectors. Two positions were identified per site with the greatest power density values. Exposures from these base stations were generally found to be in the range of 0.313 to 0.00000149% of the ICNIRP general public reference level, and the greatest exposure near any of the base stations was 21:96 mW m-2 for a wideband measurement in the 75-3000 MHz frequency range. Analysis of the measured data reveals several trends for different mobile bands with respect to maximum exposure in those locations. Additionally, a simplified calculation method for the electromagnetic fields was used to compare calculated and the measured data. It was determined, on the basis of both results of the measurements and calculations carried out for these selected base stations, that members of the public would not be exposed to in excess of a small fraction of the ICNIRP guidelines at any of those sites. These are first such measurements to be made in the Middle East and provide assurance that exposures in this region of the world do not seem to be any greater than elsewhere. [ABSTRACT FROM AUTHOR]

Computed tomography (CT) examinations have increased significantly in recent years due to technological innovations. In some industrialised countries, CT contributes to the population dose as much as background radiation. In developing countries, the uses and risks of CT have not been well characterised. The purpose of this investigation was to assess potential stochastic and deterministic radiation effects from common CT exams performed in six hospitals of Recife, Pernambuco. Scanning parameters and patient gender and age were collected for a total of 285 patients undergoing CT examinations of the head (90), chest (75), abdomen (60) and abdomen-pelvis (60). The organ doses, which were calculated using the ImPACT dosimetry calculator, varied significantly among institutions. Organs such as the brain, the heart and the eye lenses, which exhibited doses as high as 85, 42 and 100 mGy, respectively, are of concern for the production of cerebrovascular and cardiovascular diseases and cataracts. Effective cancer risks were calculated using Brenner methodology and BEIR-VII risk factors. They range from 1.8 to 110.2 cases per 100 000 persons for cancer induction and from 1.5 to 63.0 cases per 100 000 for cancer mortality. To reduce doses, a quality assurance programme that includes procedural justification and radiation protection optimisation should be implemented. [ABSTRACT FROM AUTHOR]

Consideration of uncertainties on doses can provide numerical estimates of the reliability of the protection quantities (dose coefficients) used in radiation protection to assess exposures to radionuclides that enter the body by ingestion or inhalation ('internal emitters'). Uncertainty analysis methods have been widely applied to quantify uncertainties on doses, including effective dose. However, it is not always clear how the distributions of effective dose per unit intake that result from such analyses should be interpreted with respect to the intended use of effective dose in radiation protection and the use of dose coefficients as reference values. The ICRP system of radiological protection is reviewed briefly and it is argued that the reliability of an effective dose coefficient as a protection device can best be determined by comparing the nominal detriment adjusted cancer risk associated with the dose coefficient, with a best estimate of risk for the exposure pathway and exposed population group, considering uncertainties in biokinetic, dosimetric and risk parameters. Because it is the uncertainty on the population mean of this quantity that is required, the effect of parameter variability should be distinguished from the effect of parameter uncertainty when performing uncertainty analyses. A methodology for performing the uncertainty analysis is discussed and studies that quantify uncertainty on doses and risk from intakes of radionuclides are reviewed. [ABSTRACT FROM AUTHOR]