Funding for radiation research: past, present and future.

For more than a century, ionizing radiation has been indispensable mainly in medicine and industry. Radiation research is a multidisciplinary field that investigates radiation effects. Radiation research was very active in the mid- to late 20th century, but has then faced challenges, during which time funding has fluctuated widely. Here we review historical changes in funding situations in the field of radiation research, particularly in Canada, European Union countries, Japan, South Korea, and the US. We also provide a brief overview of the current situations in education and training in this field. A better understanding of the biological consequences of radiation exposure is becoming more important with increasing public concerns on radiation risks and other radiation literacy. Continued funding for radiation research is needed, and education and training in this field are also important.

The Work of ICRP on the Ethical Foundations of the System of Radiological Protection.

The International Commission on Radiological Protection (ICRP) has established Task Group 94 (TG 94) to develop a publication on the ethical foundations of the system of radiological protection aiming to consolidate the basis of ICRP's recommendations, to improve the understanding of the system and to provide a basis for communication on radiation risk and its perception. Through the review of the publications of the Commission and the conduct of a series of workshops, TG 94 has identified the key components of the ethical theories and principles relevant to the system of radiological protection. The purpose of eliciting the ethical values underpinning the system of radiological protection is not only to clarify the rationale of the recommendations made by the Commission, but also to assist in discussions related to its practical implementation. The report nearing completion by TG 94 will present the key steps concerning the scientific, ethical and practical evolutions of the system of radiological protection since the first ICRP publication in 1928, describe the core ethical values underpinning the present system and address the key procedural aspects for its implementation.

Core ethical values of radiological protection applied to Fukushima case: reflecting common morality and cultural diversities.

The International Commission on Radiological Protection (ICRP) has established Task Group 94 (TG94) to develop a publication to clarify the ethical foundations of the radiological protection system it recommends. This TG identified four core ethical values which structure the system: beneficence and non-maleficence, prudence, justice, and dignity. Since the ICRP is an international organization, its recommendations and guidance should be globally applicable and acceptable. Therefore, first this paper presents the basic principles of the ICRP radiological protection system and its core ethical values, along with a reflection on the variation of these values in Western and Eastern cultural traditions. Secondly, this paper reflects upon how these values can be applied in difficult ethical dilemmas as in the case of the emergency and post-accident phases of a nuclear power plant accident, using the Fukushima case to illustrate the challenges at stake. We found that the core ethical values underlying the ICRP system of radiological protection seem to be quite common throughout the world, although there are some variations among various cultural contexts. Especially we found that 'prudence' would call for somewhat different implementation in each cultural context, balancing and integrating sometime conflicting values, but always with objectives to achieve the well-being of people, which is itself the ultimate aim of the radiological protection system.

A polygon-surface reference Korean male phantom (PSRK-Man) and its direct implementation in Geant4 Monte Carlo simulation.

Even though the hybrid phantom embodies both the anatomic reality of voxel phantoms and the deformability of stylized phantoms, it must be voxelized to be used in a Monte Carlo code for dose calculation or some imaging simulation, which incurs the inherent limitations of voxel phantoms. In the present study, a voxel phantom named VKH-Man (Visible Korean Human-Man), was converted to a polygon-surface phantom (PSRK-Man, Polygon-Surface Reference Korean-Man), which was then adjusted to the Reference Korean data. Subsequently, the PSRK-Man polygon phantom was directly, without any voxelization process, implemented in the Geant4 Monte Carlo code for dose calculations. The calculated dose values and computation time were then compared with those of HDRK-Man (High Definition Reference Korean-Man), a corresponding voxel phantom adjusted to the same Reference Korean data from the same VKH-Man voxel phantom. Our results showed that the calculated dose values of the PSRK-Man surface phantom agreed well with those of the HDRK-Man voxel phantom. The calculation speed for the PSRK-Man polygon phantom though was 70-150 times slower than that of the HDRK-Man voxel phantom; that speed, however, could be acceptable in some applications, in that direct use of the surface phantom PSRK-Man in Geant4 does not require a separate voxelization process. Computing speed can be enhanced, in future, either by optimizing the Monte Carlo transport kernel for the polygon surfaces or by using modern computing technologies such as grid computing and general-purpose computing on graphics processing units programming.

Radon exposure assessment for underground workers: a case of Seoul Subway Police officers in Korea.

The objective of this study is the systematic and individual assessment of the annual effective dose due to inhaled radon for the Seoul Subway Police officers, Korea. The annual average radon concentrations were found to be in the range of 18.9-114 Bq·m(-3) in their workplaces. The total annual effective doses which may likely to be received on duty were assessed to be in the range of 0.41-1.64 mSv·y(-1). These were well below the recommended action level 10 mSv·y(-1) by ICRP. However, the effective doses were higher than subway station staff in Seoul, Korea.

Use of photographic images to construct voxel phantoms for use in whole-body counting.

Quantification of radioactivity in the body by in vivo bioassay uses counting efficiencies obtained from calibration from a phantom. Usually a standardised BOMAB (Bottle Manikin Absorption) phantom is employed for whole-body counting. The physical size of workers being counted, however, may differ from the calibration phantom, and can be a source of significant errors in dose estimates. A methodology was developed applying subject-specific efficiency data determined by Monte Carlo simulation based on a voxel phantom that was constructed from photographic images of the subject. This approach was demonstrated using a BOMAB phantom. The measured and calculated efficiencies agreed well, with maximum deviation of 30 % at 1.836 MeV (Y-88 gamma-rays). The expected counting efficiencies for an obese volunteer appear higher compared with a BOMAB phantom. This is caused by a closer distance between the detector and the body surface. The fast construction technique of voxel phantoms will contribute to a reduction in uncertainty caused by variations in the counting geometry.

Implementation of the ICRP 2007 recommendations in Korea.

The International Commission on Radiological Protection (ICRP) published the new recommendations 2007 on radiological protection. International Atomic Energy Agency (IAEA) is also under process in revising its International Basic Safety (BSS). According to revision of the ICRP recommendations and BSS, the Korean government plans to implement those changes. In the 2007 ICRP recommendations, there are some new concepts, principles and quantities. Based on the study carried out by Korea Institute of Nuclear Safety (KINS) so far, the following points are identified as major areas that need further in-depth review and consideration for the implementation of the ICRP 2007 recommendations into Korean radiation protection laws and regulations; changes in the radiation risk factors, radiation weighting factors and tissue weighting factors, maintenance of the ICRP 60 dose limits, practical application of the dose constraints and determination of the reference levels in many source to individual exposure relationships, change from process-based system to exposure situation-based system, strengthening of the principle of optimization in all exposure situations, system of radiation protection for the environment, practical application of the exclusion and exemption principles, active participation of the stakeholders, changes in glossary etc. The study for the implementation of the ICRP 2007 recommendations into national legislations will be conducted till the end of 2012. In the meantime, draft regulations will be developed and the possible impact on the nuclear industry will also be analyzed and active involvement of the stakeholders including licensees will be encouraged in the entire process. The final draft of the revised laws and regulations will be issued in the early of 2013 and the formal legislation process of this final draft will commence in due course.