Bridgewire
Definition
The high-resistance wire element within an electric detonator, typically nichrome or platinum-iridium, that converts firing current into heat to ignite the pyrotechnic primer. Bridgewire alloy composition is a forensic identifier for detonator manufacturer and product line.
- Location
- Inside an electric detonator
- Common materials
- Nichrome, platinum-iridium
- Function
- Converts firing current to heat, ignites primer
- Forensic use
- Alloy composition can identify manufacturer and product line
Common questions
How does bridgewire evidence survive a detonation for forensic examination?+
Fragments of the bridgewire and surrounding detonator components can survive close to the seat of an explosion and are recovered during post-blast scene searches, then examined for alloy composition and construction details that help trace the detonator's origin.
What does bridgewire alloy analysis actually tell investigators?+
Comparing the recovered wire's composition against known manufacturer specifications can narrow down the detonator type and, in some cases, the specific product line or batch, which supports tracing the device back through legitimate or illicit supply chains.
Related terms
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