Recently, we reported on a novel ex situ thermal impulse sensing technique (based on lanthanide-doped oxide precursor nanoparticles) for use in structural fire forensics and demonstrated its functionality in small-scale lab-based tests. As a next step we have now performed a large-scale lab test at the US Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) Fire Research Laboratory using a burn chamber with three sand burners. In this test we demonstrate our technique’s ability to determine the average temperature experienced by surfaces during the fire. While we successfully demonstrate our techniques accuracy, we also discover several previously unknown vulnerabilities. Namely, we find that: (1) our current method of embedding sensors in paint results in our sensor particles being difficult to recover (due to a large quantity of debris), (2) the current test panels have poor survivability, (3) debris from the fire tests interferes with excitation of dopant Dy ions (limiting our sensors’ functionality), and (4) dispersal in paint results in suppression of the (metastable)tetragonal-to-monoclinic phase transition of ZrO2. To overcome these vulnerabilities we are evaluating new panel materials, paints, and lanthanide-dopants.

中文翻译：

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异地热脉冲传感器的燃烧室测试

最近，我们报道了一种用于结构火灾取证的新型异位热脉冲传感技术（基于镧系元素掺杂的氧化物前体纳米颗粒），并在小规模实验室测试中证明了其功能。作为下一步，我们现在使用带有三个沙子燃烧器的燃烧室在美国酒精、烟草、枪支和爆炸物 (ATF) 火灾研究实验室进行了大规模的实验室测试。在这个测试中，我们展示了我们的技术能够确定火灾期间表面所经历的平均温度。虽然我们成功展示了我们的技术准确性，但我们还发现了几个以前未知的漏洞。即，我们发现：（1）我们目前在油漆中嵌入传感器的方法导致我们的传感器颗粒难以恢复（由于大量碎片），(2) 当前测试面板的生存能力较差，(3) 火灾测试产生的碎片会干扰掺杂剂 Dy 离子的激发（限制我们传感器的功能），以及 (4) 油漆中的分散导致（亚稳态）四方离子的抑制ZrO2 向单斜晶相转变。为了克服这些漏洞，我们正在评估新的面板材料、油漆和镧系元素掺杂剂。