Raman Microspectroscopic Mapping: A Tool for Identification of Fused Materials in Fire Debris

Abstract

Examination of fire debris can provide information about the types of materials which were present at the time of the fire to give insights for fire scene reconstruction and understanding compartment fire dynamics. This paper demonstrates the ability of Raman spectroscopy for material identification postfire in complex situations, such as the production of fused masses during fire dropdown. A validated Raman spectral library is combined with Raman mapping in three fire case studies, to determine the individual materials in the fused masses formed. The case studies accessed material combinations of several common polymers. Raman mapping was carried out on a 10 μm × 10 μm square of the masses. Material identification using this technique ranged from a high of 85% match to a low of 40% match. This work demonstrated that complex masses found in the fire debris can be resolved into the individual material components for identification and spatial distribution.

Forensic investigation of arson residue by infrared and Raman spectroscopy: From conventional to non-destructive techniques

“…Fire-debris and accelerant analysis are among the most difficult analytical tasks. 21,24 Materials associated with fire and arson change their chemical structure post burning, and this can make identification difficult. 21,24 Non-destructive spectroscopic techniques are emerging as the best analytical tools for evidence analysis because of their sensitivity, as in most of cases, the sample may be found in trace amounts.…”

“…21,24 Materials associated with fire and arson change their chemical structure post burning, and this can make identification difficult. 21,24 Non-destructive spectroscopic techniques are emerging as the best analytical tools for evidence analysis because of their sensitivity, as in most of cases, the sample may be found in trace amounts. 21–25 The rapid, sensitive, quantitative, confirmatory and non-invasive nature of these techniques enables preservative analytical approaches, which in turn helps in the re-analysis in cases of disputed analytical results.…”

“…21,24 Non-destructive spectroscopic techniques are emerging as the best analytical tools for evidence analysis because of their sensitivity, as in most of cases, the sample may be found in trace amounts. 21–25 The rapid, sensitive, quantitative, confirmatory and non-invasive nature of these techniques enables preservative analytical approaches, which in turn helps in the re-analysis in cases of disputed analytical results. 22,23,25 Hence, the spectroscopic methods are superior in comparison to the other destructive techniques (i.e.…”

“…The combination of these two spectroscopic techniques is exclusively considered as vibrational spectroscopy. 21,24 Molecular vibrations reveal characteristic information about the structure of a substance. IR and Raman spectroscopy can reveal the structure of molecules to identify any substance.…”

“…21–25 The application of various instrumental analytical tools for the analysis of fire debris has also been critically discussed. 2–26…”