[Radiation hygiene in medical X-ray imaging: part 2: Assessment of radiation exposure and radiation protection measures]

In order to secure and continually improve radiation protection standards in the field of medical X-ray imaging, the German X-Ray Ordinance requires that each individual examination be properly justified and that any procedure undertaken be optimized. Diagnostic reference levels have been introduced in Germany as a measure of optimization for common and/or high-dose X-ray procedures, and are regularly checked for compliance by the competent Medical Experts Office. A prerequisite for the implementation of these regulatory requirements is the determination of readily measurable dose quantities. They also form the basis for the estimation of organ doses and of the effective dose for exposure and risk assessment. The aim of this paper is to describe the essential dosimetric concepts and methods used for the assessment of radiographic, fluoroscopic, and CT procedures. In addition, practical measures for reducing the radiation exposure of patients and personnel will be discussed.

Revision of the Euratom Basic Safety Standards Directive--current status

The European Commission is currently developing a revised Euratom Basic Safety Standards (BSS) Directive covering two major objectives: the consolidation of existing Euratom Radiation Protection legislation and the revision of the Euratom BSS. The consolidation will merge the following five Directives into one single Directive: the BSS Directive, the Medical Exposures Directive, the Public Information Directive, the Outside Workers Directive and the Directive on the Control of high-activity sealed radioactive sources and orphan sources. The revision of the Euratom BSS will take account of the latest recommendations by the International Commission on Radiological Protection and shall improve clarity of the requirements where appropriate. It is planned to introduce more binding requirements on natural radiation sources, on criteria for exemption and clearance, and on the cooperation between Member States for emergency planning and response. The provisions for regulatory control of planned exposure situations foresee a graded approach commensurate to the magnitude and likelihood of exposures from a practice. Finally, the new BSS shall take account of recent scientific developments. One additional goal is to achieve greater harmonisation between the Euratom BSS and the international BSS. While the requirements on the protection of workers, apprentices and students remain nearly unchanged, the revised BSS will clarify the roles and responsibilities of services and experts involved in technical and practical aspects of radiation protection, such as the occupational health services, the dosimetry services, the radiation protection expert and the medical physics expert. The requirements in the BSS on individual monitoring of category A workers remain unchanged, but the existing guidance on individual monitoring was revised and updated--the technical recommendations for monitoring individuals occupationally exposed to external radiation are published by the European Commission. This paper summarises the current status of the revision of the Euratom BSS Directive.

Performance and approval procedures for active personal dosemeters

Active personal dosemeters (APDs) are well accepted as useful and reliable instruments for individual dosimetry measurements. The increasing concern about studying the behaviour of APDs in pulsed fields is illustrated through revision of the results of the most representative studies on the performance of APDs in the last 5 y. The deficiencies of APDs in pulsed fields are discussed together with proposals to overcome them. Although there are no legal constraints or technical limitations for recognising APDs for legal dosimetry in facilities with continuous radiation fields, APDs continue to be mainly used as operational dosemeters. The approval procedures applicable to APDs, especially the approach undertaken by Germany, are presented. Finally, some trends in the developments and use of APDs are summarised.

Summary of the Forty-Fifth NCRP annual meeting on "the future of nuclear power worldwide: safety, health and the environment"

The role of nuclear power as a major resource in meeting the projected growth of electric power requirements in the United States and worldwide during the 21st century is a subject of great contemporary interest. The goal of the 2009 NCRP Annual Meeting was to provide a forum for an in-depth discussion of issues related to the safety, health and environmental protection aspects of new nuclear power reactor systems and related fuel-cycle facilities such as fuel production and reprocessing strategies. The meeting was an international conference with participation of almost 400 representatives from many nations, scientific organizations, nuclear industries, and governmental agencies engaged in the development and regulatory control of advanced nuclear reactor systems and fuel-cycle operations. Highlights of the meeting are summarized in this report.

Role of the International Radiation Protection Association

Global concerns over energy supply and climate change have given rise to an increase in uranium prospecting, mining and extraction. The changing world economy is spreading the use of advanced nuclear and radiation-related technologies to many parts of the world, giving rise to global initiatives on nuclear energy and operation of nuclear fuel cycle facilities. The emerging global nuclear safety regime promotes and encourages high standards of radiation safety worldwide. These developments call for increasing capacity and capabilities in radiation protection expertise and continue to present both challenges and opportunities to the International Radiation Protection Association (IRPA), an association of 46 societies representing 58 countries with an individual membership of approximately 17,000. IRPA's objectives include: (1) assisting the development of competent radiation protection programs; (2) fostering the exchange of scientific and technical information through its international and regional congresses; (3) promoting the scientific and professional recognition of the radiation protection expert; and (4) supporting continuing education programs at each IRPA congress. IRPA has adopted a Code of Ethics and Guiding Principles for the Conduct of Stakeholder Engagement. Recently work began to develop guidance for maintaining and improving current levels of radiation protection and transferring this culture to future radiation protection professionals. These IRPA projects are developed through the Associate Society Forum discussions that are held at each IRPA international and regional congress. Finally, IRPA maintains a close working relationship with various international organizations and is also represented on the Inter-Agency Committee on Radiation Safety.

New nuclear build and evolving radiation protection challenges

Radiological protection has continued to evolve in order to meet emerging challenges and will continue to do so. This paper will discuss the scientific and social challenges that will or may be faced by the radiological protection community in the coming 10 to 20 y and how these may affect what is expected to be a renewed interest in building and operating nuclear power plants for electricity generation.

Decommissioning a phosphoric acid production plant: a radiological protection case study

During a preliminary survey at the area of an abandoned fertilizer plant, increased levels of radioactivity were measured at places, buildings, constructions and materials. The extent of the contamination was determined and the affected areas were characterized as controlled areas. After the quantitative and qualitative determination of the contaminated materials, the decontamination was planned and performed step by step: the contaminated materials were categorized according to their physical characteristics (scrap metals, plastic pipes, scales and residues, building materials, etc) and according to their level of radioactivity. Depending on the material type, different decontamination and disposal options were proposed; the most appropriate technique was chosen taking into account apart from technical issues, the legal framework, radiation protection issues, the opinion of the local authorities involved as well as the owner's wish. After taking away the biggest amount of the contaminated materials, an iterative process consisting of surveys and decontamination actions was performed in order to remove the residual traces of contamination from the area. During the final survey, no residual surface contamination was detected; some sparsely distributed low level contaminated materials deeply immersed into the soil were found and removed.

[Duties of the radiologist for the radiation protection of radiation workers]

After a risk analysis has been completed by the radiation safety officer, all entities where a source of ionizing radiation is present must established a monitored or controlled zone containing the source. When exposure exceeds the maximum regulatory dose, a dedicated color-coded controlled (yellow or orange) or restricted zone must be established. All assessments performed by the RSO should reflect normal working conditions. From these results, workers can be divided into two categories, A or B, based on their level of exposure. The workers should undergo medical and dosimetric follow-up with the use of passive dosimetry. The use of operational dosimetry should be added when working in a controlled zone. A radiation dosimetry report for each worker should be available to the occupational medicine provider to ensure appropriate dosimetric monitoring.

[The radiologist's responsibilities for the radiation protection of patients]

The obligations of the radiologist for the radiation protection of patients include a review of the appropriateness of the examination and optimization of the protocol. Both internal and external quality assurance programs are mandatory. The specific tasks and their frequency are defined by the AFSSAPS. The radiology report of procedures performed over radiosensitive regions must include the delivered dose. The imaging technique must be optimized based on published guidelines or law for the most frequent examinations. All radiologists should be familiar with radiation protection. Incidents should be reported to the Nuclear Safety Authority.

Practical and effective ALARA

The ALARA Principle ensures that the total effective dose equivalent is minimized subject to economic and social factors. Effective ALARA programs must include the participation of all facility workgroups, management support, teamwork, and strong leadership. The development and sustainability of effective ALARA programs require the establishment and monitoring of goals, rewarding the successful achievement of those goals, and incorporating lessons learned from tasks that fail to meet their goals.

Medical radiation exposure and accidents. Dosimetry and radiation protection. Do we only benefit the patient?

This article presents and discusses new information on the old Hippocratic moto of "...not to harm but to benefit the patient". Some radiation accidents are due to medical errors. Millions of medical tests exposing radiation are performed every day worldwide increasing and sometimes exceeding the annual permissible dose administered to the general population. Public authorities are now seriously concerned about medical radiation overused. In U.S.A. both the House of Representatives and the Food and Drug Administration have recently delt with this problem. Others and we have suggested before and the International Atomic Energy Agency now proposes: a "Smart Card" for every individual who receives medical radiation. In this card the amount of medical radiation administered will be recorded. It is time to issue rules for protection of the public from medical radiation overdose.

Radiation exposure control from the application of nuclear gauges in the mining industry in Ghana

The use of nuclear gauges for process control and elemental analysis in the mining industry in Ghana, West Africa, is wide spread and on the increase in recent times. The Ghana Radiation Protection Board regulates nuclear gauges through a system of notification and authorization by registration or licensing, inspection, and enforcement. Safety assessments for authorization and enforcement have been established to ensure the safety and security of radiation sources as well as protection of workers and the general public. Appropriate training of mine staff is part of the efforts to develop the necessary awareness about the safety and security of radiation sources. The knowledge and skills acquired will ensure the required protection and safety at the workplaces. Doses received by workers monitored over a period between 1998 and 2007 are well below the annual dose limit of 20 mSv recommended by the International Commission on Radiological Protection.

Guidelines for the labelling of leucocytes with (111)In-oxine. Inflammation/Infection Taskgroup of the European Association of Nuclear Medicine

We describe here a protocol for labelling autologous white blood cells with (111)In-oxine based on previously published consensus papers and guidelines. This protocol includes quality control and safety procedures and is in accordance with current European Union regulations and International Atomic Energy Agency recommendations.

Guidelines for the labelling of leucocytes with (99m)Tc-HMPAO. Inflammation/Infection Taskgroup of the European Association of Nuclear Medicine

We describe here a protocol for labelling autologous white blood cells with (99m)Tc-HMPAO based on previously published consensus papers and guidelines. This protocol includes quality control and safety procedures and is in accordance with current European Union regulations and International Atomic Energy Agency recommendations.

Protection of the environment from ionising radiation in a regulatory context (protect): proposed numerical benchmark values

Criteria are needed to be able to judge the level of risk associated with dose rates estimated for non-human biota. In this paper, European guidance on the derivation of predicted no-effect chemical concentrations has been applied to appropriate radiation sensitivity data. A species sensitivity distribution fitted to the data for all species resulted in a generic predicted no-effect dose rate of 10 microGy h(-1).Currently, data are inadequate to derive screening values for separate organism groups. A second, higher, benchmark could aid in decision making by putting results into context on the scale of no effect to a risk of 'serious' effect. The need for, meaning and use of such a value needs to be debated by the wider community. This paper explores potential approaches of deriving scientific input to this debate. The concepts proposed in this paper are broadly consistent with the framework for human protection.

The effects of the Brazilian regulatory inspection programme on nuclear medicine facilities

This paper aims to demonstrate the importance of the regulatory inspections carried out by the Brazilian regulatory body in the area of nuclear medicine. The main aspects observed during the inspections are presented as well as the time evolution of the non-compliances, according to their occurrence by type. We also evaluate factors concerning the working of the nuclear medicine facility responsible for solving the non-compliances. The results suggest a decrease of occurrence of non-compliances with time that can be related to the strictness of the inspections and the awareness of the personnel in the nuclear medicine facilities. An analysis of radiation dose exposure levels for the professionals involved in nuclear medicine was carried out; although dose values are below regulatory dose limits, their occurrence is not decreasing satisfactorily. Results indicate the need for staff training and commitment of the responsible nuclear medicine facility staff to the radiological protection procedures. Our results also emphasise the importance of continuous coercive actions to improve the level of radiological protection in nuclear medicine facilities in compliance with the standards established by the national regulatory authority and international recommendations.

Survey of the cosmetic use of lasers and other strong optical radiation sources

A survey was undertaken regarding the extent to which optical radiation is used in cosmetic treatments and the compliance with national regulations. Questionnaires were sent to 65 clinics, and 23 of these were later inspected. Only one of 41 class 4 lasers had been reported to the authorities according to the regulations prior to the survey. Among sources other than lasers, intense pulsed light (IPL) sources were the most frequent. Although qualified health personnel should be in charge of the treatment, it was observed that 30% of the clinics did not fulfil this requirement. Deviations with respect to personnel training, availability of written procedures, protective equipment and warning signs were frequently observed. The results give rise to concern about the safety of patients and employees.

The use of mobile computed tomography in intensive care: regulatory compliance and radiation protection

The use of mobile head computed tomography (CT) equipment in intensive care is of benefit to unstable patients with brain injury. However, ionising radiation in a ward environment presents difficulties due to the necessity to restrict the exposure to staff and members of the public according to regulation 8(1-2) of the Ionising Radiation Regulations 1999. The methodology for enabling the use of a mobile head CT unit in an open ward area is discussed and a practical solution given. This required the reduction in scatter doses through the installation of extra internal and external shielding, and a further reduction in annual scatter dose by restricting the use of the equipment based on a simulation of the annual ward workload.

How do we combine science and regulations for decision making following a terrorist incident involving radioactive materials?

Approaches to safety regulations-particularly radiation safety regulations-must be founded on the very best science possible. However, radiation safety regulations always lag behind the science for a number of reasons. First, the normal scientific process of peer-review, debate, and confirmation must ensure that the conclusions are indeed correct, the implications of the research are fully understood, and a consensus has been established. Second, in the U.S., there is a well-established, all-inclusive political process that leads to changes in radiation safety regulations. This process can take a very long time, as was demonstrated when the process was initiated to change the Code of Federal Regulations more than 20 y ago in response to International Commission on Radiation Protection Publication 26 and other recommendations. Currently, we find ourselves in a situation where the possibility of a terrorist radiological attack may occur and where the existing body of regulations provides very little guidance. Many international and national bodies, including several federal agencies, have provided recommendations on the appropriate levels of exposure for first-responders and first-receivers, as well as for the general public. However, some agencies provide guidelines based on very conservative dose limits which are not appropriate in situations where there is a substantial chance for the loss of lives and critical infrastructure. It is important that an emergency response is not hampered by overly cautious guidelines or regulations. In a number of exercises the impact of disparate guidelines and training in radiological situations has highlighted the need for clear reasonable limits that maximize the benefit from an emergency response and for any cleanup after the incident. This presentation will focus first on the federal infrastructure established to respond to radiological accidents and incidents. It will review briefly the major recommendations, both international and national, for responders and will attempt, where possible, to establish the scientific foundation for these guidelines. We will also stress the need to clearly and openly communicate the recommendations to the first-responders and the public so that no unnecessary anxiety or associated actions on their part impedes the ability to respond to a disaster. Finally, the use of these guidelines and recommendations by decision-makers at all levels will be discussed.

Radioactive waste management and decommissioning of accelerator facilities

During the operation of high-energy accelerators, the interaction of radiation with matter can lead to the activation of the machine components and of the surrounding infrastructures. As a result of maintenance operation and during decommissioning of the installation, considerable amounts of radioactive waste are evacuated and shall be managed according to the radiation-protection legislation. This paper gives an overview of the current practices in radioactive waste management and decommissioning of accelerators.

Perspectives of U.S. government agencies on the potential role of greater scientific understanding of low-dose radiation effects in establishing regulatory health protection guidance

This paper summarizes the perspectives of three U.S. federal agencies on the potential long-term influence of new findings on the biological and potential health effects of low dose and low dose-rate radiation on regulatory controls placed on exposures in occupational, medical, and public settings.

Work to save dose: contrasting effective dose rates from radon exposure in workplaces and residences against the backdrop of public and occupational regulatory limits

Office workers are exposed to radon while at work and at home. Though there are a multitude of studies reporting radon concentrations and potential lung and effective doses associated with radon progeny exposure in homes, similar studies in non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more "typical" workplace with residential exposures within the same county. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed for 3-mo sampling periods in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico. The measured concentrations were used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about 8 times greater exposure at home than while in the office (2.3 mSv y-1 vs. 0.3 mSv y-1). The estimated effective dose rate for a more homebound person was about 3 mSv y-1. Estimating effective doses from background radon exposure in the same county as Los Alamos National Laboratory, with thousands of "radiological workers," highlights interesting contrasts in radiation protection standards that span public and occupational settings. For example, the effective dose rate from background radon exposure in unregulated office spaces ranged up to 1.1 mSv y-1, which is similar to the 1 mSv y-1 threshold for regulation of a "radiological worker," as defined in the Department of Energy regulations for occupational exposure. Additionally, the estimated average effective dose total of >3 mSv y-1 from radon background exposure in homes stands in contrast to the 0.1 mSv y-1 air pathway effective public dose limit regulated by the Environmental Protection Agency for radioactive air emissions, and both these are substantially lower than effective doses associated with priority radon levels in homes of "tens of pCi L-1 and greater" (>370 Bq m-3), as suggested by the Health Physics Society.

Neutron dose per fluence and weighting factors for use at high energy accelerators

In June 2007, the United States Department of Energy incorporated revised values of neutron weighting factors into its occupational radiation protection regulation Title 10, Code of Federal Regulations Part 835, as part of updating its radiation dosimetry system. This has led to a reassessment of neutron radiation fields at high energy accelerators such as those at the Fermi National Accelerator Laboratory (Fermilab) in the context of the amended regulation and contemporary guidance of the International Commission on Radiological Protection (ICRP). Values of dose per fluence factors appropriate for accelerator radiation fields calculated elsewhere are collated and radiation weighting factors compared. The results of this revision to the dosimetric system are applied to americium-beryllium neutron energy spectra commonly used for instrument calibrations. Also, a set of typical accelerator neutron energy spectra previously measured at Fermilab are reassessed in light of the new dosimetry system. The implications of this revision and of recent ICRP publications are found to be of moderate significance.