Blast Seat
Definition
The origin point of an explosion, characterised by a crater (in contact detonations), radiating damage patterns, and the highest concentration of explosive residues. Evidence collection begins at the blast seat and radiates outward.
- Definition
- Origin point of an explosion
- Contact detonation sign
- Crater at the seat
- Evidence concentration
- Highest residue levels at the seat
- Collection order
- Begins at seat, radiates outward
Common questions
Why does explosive residue concentration peak at the blast seat?+
Unreacted or partially reacted explosive particles are deposited closest to the point of detonation before being carried outward and diluted by the blast wave, so the seat area typically yields the best chemical evidence for identifying the explosive used.
How do investigators locate the blast seat when no obvious crater is present?+
In a non-contact or elevated detonation, investigators look for the radial pattern of fragment scatter, structural damage severity, and directional witness marks converging on a common origin point rather than relying on a crater alone.
Related terms
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- Daubert Standard
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- Forensic Explosives Laboratory (FEL)
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- Ion Chromatography (IC)
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