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Burn Chamber Test of Ex Situ Thermal Impulse Sensors

NCJ Number
Applied Spectroscopy Volume: 74 Issue: 5 Dated: 2020 Pages: 515-524
Date Published
10 pages

Having recently 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, the current article reports on a next step in which the authors performed a large-scale lab test at the U.S. Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) Fire Research Laboratory, using a burn chamber with three sand burners.


This test demonstrated the technique’s ability to determine the average temperature experienced by surfaces during the fire. Although the test demonstrated the technique’s accuracy, it also revealed several previously unknown vulnerabilities. It found that (1) the current method of embedding sensors in paint results in 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 sensors’ functionality); and (4) dispersal in paint results in suppression of the (metastable)tetragonal-to-monoclinic phase transition of ZrO2. To overcome these vulnerabilities, the authors are currently evaluating new panel materials, paints, and lanthanide-dopants. (publisher abstract modified)

Date Published: January 1, 2020