The European Space Agency (ESA) is currently expanding its efforts in identifying requirements and promoting research towards optimizing radiation protection of astronauts. Space agencies use common limits for tissue (deterministic) effects on the International Space Station. However, the agencies have in place different career radiation exposure limits (for stochastic effects) for astronauts in low-Earth orbit missions. Moreover, no specific limits for interplanetary missions are issued. Harmonization of risk models and dose limits for exploratory-class missions are now operational priorities, in view of the short-term plans for international exploratory-class human missions. The purpose of this paper is to report on the activity of the ESA Topical Team on space radiation research, whose task was to identify the most pertinent research requirements for improved space radiation protection and to develop a European space radiation risk model, to contribute to the efforts to reach international consensus on dose limits for deep space. The Topical Team recommended ESA to promote the development of a space radiation risk model based on European-specific expertise in: transport codes, radiobiological modelling, risk assessment, and uncertainty analysis. The model should provide cancer and non-cancer radiation risks for crews implementing exploratory missions. ESA should then support the International Commission on Radiological Protection to harmonize international models and dose limits in deep space, and guarantee continuous support in Europe for accelerator-based research configured to improve the models and develop risk mitigation strategies.

欧洲航天局（ESA）目前正在努力确定要求并促进研究，以优化宇航员的辐射防护。太空机构对国际空间站上的组织（确定性）影响使用通用限制。但是，这些机构对低地球轨道飞行任务中的宇航员制定了不同的职业辐射暴露极限（出于随机影响）。此外，没有发布行星际飞行的具体限制。鉴于国际探索性人类飞行任务的短期计划，协调探索性飞行任务的风险模型和剂量限值现已成为业务优先事项。本文的目的是报告ESA空间辐射研究专题小组的活动，其任务是确定最相关的研究要求，以改善空间辐射防护，并发展欧洲空间辐射风险模型，为在深空剂量限制方面达成国际共识做出努力。专题小组建议欧空局根据欧洲在以下方面的专门知识，促进发展空间辐射风险模型：运输守则，放射生物学建模，风险评估和不确定性分析。该模型应为执行探索性任务的工作人员提供癌症和非癌症辐射的风险。然后，欧空局应支持国际放射防护委员会协调外层空间的国际模式和剂量限值，