International coordination of research: EPRI International Dose Effect Alliance.

Purpose: The key to increasing our understanding of low dose effects of ionizing radiation is cooperation and communication between research organizations around the world. The purpose of this article is to describe the Electric Power Research Institute (EPRI) program for such cooperation. Materials and methods: EPRI is an independent, non-profit organization dedicated to research support for the generation, transmission, and utilization of electricity. As part of its robust program, EPRI has sought to support research into low dose ionizing radiation health effects. Starting in 2016, one piece of the radiation safety program has been the International Dose Effect Alliance (IDEA), the mission of which is to organize collaborative meetings to bring together researchers from around the world to discuss research agendas, programs, and priorities. Results: IDEA workshops were held in the fall of 2016 and 2017, and were successful in starting the dialogue toward increased collaboration within the United States, Canada, Asia, and Europe. EPRI supports global collaboration and cooperation as a key opportunity to build upon the work being undertaken throughout the world to create a unified effort to answer the questions of low dose and dose rate ionizing radiation health effects. The International Workshop on the Biological Effects of Radiation, which was held in Osaka, Japan in March 2018, provided a further opportunity to expand upon the initiative for global collaboration. Conclusions: Significant advances are being achieved through the IDEA program, and the Osaka workshop held in Japan in March 2018 has further contributed to the initiative.

Health Risks From Low Doses and Low Dose-Rates of Ionizing Radiation. Session 5: Future of Radiation Protection Regulations.

The system of radiological protection is a prospective approach to protection of individuals in all exposure situations. It must be applied equitably across all age groups and all populations. This is a very different circumstance from dose assessment for a particular individual where the unique characteristics of the individual and the exposure can be taken into account. Notwithstanding the ongoing discussions on the possible shape of the dose response at low doses and dose rates, the prospective system of protection has therefore historically used a linear assumption as a pragmatic, prudent and protective approach. These radiation protection criteria are not intended to be a demarcation between "safe" and "unsafe" and are the product of a risk-informed judgement that includes inputs from science, ethics, and experience. There are significant implications for different dose response relationships. A linear model allows for equal treatment of an exposure, irrespective of the previously accumulated exposure. In contrast, other models would predict different implications. Great care is therefore needed in separating the thinking around risk assessment from risk management, and prospective protection for all age groups and genders from retrospective assessment for a particular individual. In the United States, the prospective regulatory structure functions effectively because of assumptions that facilitate independent treatment of different types of exposures, and which provide pragmatic and prudent protection. While the a linear assumption may, in fact, not be consistent with the biological reality, the implications of a different regulatory model must be considered carefully.

Summary of the NCRP 51st Annual Meeting.

Traditionally, the last presentation of the National Council on Radiation Protection and Measurements (NCRP) Annual Meeting is a summary of the presentations and discussions by the Program Committee Chair. Thus, it is now time to try to sum up a day and a half of very excellent presentations on a wide variety of subjects in this 51st Annual Meeting.