Accurately estimating the sensitivity of explosive materials is a potentially life-saving task which requires standardised protocols across nations. One of the most widely applied procedures worldwide is the so-called '1-In-6' test from the United Nations (UN) Manual of Tests in Criteria, which estimates a 'limiting stimulus' for a material. In this paper we demonstrate that, despite their popularity, limiting stimuli are not a well-defined notion of sensitivity and do not provide reliable information about a material's susceptibility to ignition. In particular, they do not permit construction of confidence intervals to quantify estimation uncertainty. We show that continued reliance on limiting stimuli through the 1-In-6 test has caused needless confusion in energetic materials research, both in theoretical studies and practical safety applications. To remedy this problem, we consider three well-founded alternative approaches to sensitivity testing to replace limiting stimulus estimation. We compare their performance in an extensive simulation study and apply the best-performing approach to real data, estimating the friction sensitivity of pentaerythritol tetranitrate (PETN).

翻译：准确评估爆炸材料的感度是一项具有潜在救生意义的工作，需要各国采用标准化测试规程。目前全球应用最广泛的测试方法之一是联合国《试验与标准手册》中的"六发一发"试验，该方法通过估算材料的"极限刺激"来评估感度。本文论证表明，尽管极限刺激概念被广泛采用，但其并非明确定义的感度指标，也不能可靠反映材料对起爆的敏感程度。特别需要指出的是，该方法无法构建置信区间以量化估计的不确定性。我们证明，通过"六发一发"试验持续依赖极限刺激的做法，已在含能材料研究领域（包括理论研究和实际安全应用）引发了不必要的混淆。为解决这一问题，我们提出了三种理论基础完善的替代性感度测试方法以取代极限刺激估计。通过大量模拟研究比较了这些方法的性能，并将最优方法应用于实际数据，对季戊四醇四硝酸酯（PETN）的摩擦感度进行了评估。