1. 13-5 Analysis of Flammable Residues
Forensic Aspects of Fire Investigation
Sanders

2. Forensic Aspects of Fire Investigation
Accelerants
Most arsons are initiated by petroleum distillate such as gasoline and kerosene.
April 24, 2019
Forensic Aspects of Fire Investigation

3. Forensic Aspects of Fire Investigation
Analyzing Residues
The gas chromatograph is the most sensitive and reliable instrument for detecting and characterizing flammable residues.
Telltale signs of suspicious fires include evidence of separate and unconnected fires, the use of “streamers“ to spread the fire from one area to another, and evidence of severe burning found on the floor as opposed to the ceiling of a structure.
April 24, 2019
Forensic Aspects of Fire Investigation

4. Forensic Aspects of Fire Investigation
Gas Chromatography
A gas chromatograph separates the hydrocarbon components to produce a chromatographic pattern consistent with a particular petroleum product.
April 24, 2019
Forensic Aspects of Fire Investigation

5. Chromatographic Peaks
By comparing select gas chromatographic peaks recovered from fire scene debris to known flammable liquids, a forensic analysis may be able to identify the accelerant used to initiate the fire.
April 24, 2019
Forensic Aspects of Fire Investigation

6. Forensic Aspects of Fire Investigation
April 24, 2019
Forensic Aspects of Fire Investigation

7. Forensic Aspects of Fire Investigation
Complex Patterns
Complex chronographic patterns can be simplified.
Passing the separate elements of the gas it column to a mass spectrometer.
April 24, 2019
Forensic Aspects of Fire Investigation

8. Forensic Aspects of Fire Investigation
GC is used to separate complex mixtures. It is much better at this than thin-layer or paper chromatography. This is because it is more sensitive - allowing the determination not only of what chemicals are in the mixture, but also how much of each chemical there is.
April 24, 2019
Forensic Aspects of Fire Investigation