Abstract

This paper outlines research on understanding, characterizing, and managing conservatisms in safety analyses. This research includes a review of national and international approaches for developing and using conservative and best-estimate analyses. A probabilistic approach is discussed to support reducing conservatism while maintaining safety margins. An example of the proposed approach is applied to two case studies for nonreactor nuclear facilities. The objective of this work is to provide a means for better understanding and managing risks associated with nuclear facilities. The results from these examples show that conservative estimates could lead to excessive safety margins when compared to the best-estimate values; the amount of excess margin may be as high as one or more orders of magnitude.

摘要

本文概述了对安全性分析中的保守性的理解，表征和管理的研究。这项研究包括对开发和使用保守和最佳估计分析的国家和国际方法的综述。讨论了一种概率方法，以支持在保持安全裕度的同时减少保守性。拟议方法的一个例子应用于非反应堆核设施的两个案例研究。这项工作的目的是提供一种更好地理解和管理与核设施有关的风险的手段。这些示例的结果表明，与最佳估计值相比，保守估计可能会导致过多的安全边际。超额保证金的金额可能高达一个或多个数量级。