Faculty of Health Sciences, College of Medicine, Department of Radiology, University of Manitoba, Winnipeg, Manitoba.
Health Phys. 2021 Feb 1;120(2):217-223. doi: 10.1097/HP.0000000000001286.
The full ALARA principle includes "as low as reasonably achievable" taking social and economic factors into consideration. The International Commission on Radiological Protection advises a conventional cost benefit approach (e.g., cost per monetized averted stochastic effects or years of life saved) to consider economic factors. Given small incremental radiation dose reductions to patients, workers, or the public that may be realized in medical settings and the correspondingly small changes to theoretical stochastic effects, a conventional cost benefit approach is less than ideal. This is illustrated in the case studies presented in this paper. Alternate approaches, such as cost per unit of radiation dose averted (e.g., $/μSv averted), cancer induction/fatality probabilistic thresholds, or thresholds relative to natural background radiation may be alternate options. However, the decision regarding what is a "safe" level of radiation and what are reasonable costs to make it "safer" are driven by societal values and may vary from jurisdiction to jurisdiction.
充分的 ALARA 原则包括“在合理可行的情况下尽量低”，同时考虑社会和经济因素。国际放射防护委员会建议采用常规的成本效益方法（例如，每避免一个货币化的随机效应或挽救的生命年的成本）来考虑经济因素。鉴于在医疗环境中可能实现的对患者、工作人员或公众的微小增量辐射剂量降低，以及对理论随机效应的相应微小变化，常规的成本效益方法并不理想。本文提出的案例研究说明了这一点。替代方法，如每避免单位辐射剂量的成本（例如，/μSv 避免）、癌症发生率/死亡率的概率阈值或与自然本底辐射的阈值，可能是替代选择。然而，关于什么是“安全”的辐射水平以及使它“更安全”的合理成本的决策是由社会价值观驱动的，并且可能因管辖范围而异。
