Victim-Operated Switch (VOS)
Definition
A firing switch that is actuated by the intended victim's own movement or action, including pressure plates, trip wires, tension-release switches, and pressure-release switches.
- Trigger
- The intended victim's own movement or action
- Types
- Pressure plate, trip wire, tension-release, pressure-release
- Contrast
- Command-initiated devices, triggered deliberately by an operator
- Relevance
- IED render-safe procedures and EOD triage
Common questions
How does a victim-operated switch differ from a command-initiated device?+
A VOS fires passively when the target's own movement or action disturbs it, while a command device is deliberately set off by an operator, either remotely or by a physical firing wire, requiring an active decision to detonate.
Why does identifying the specific VOS type matter to EOD technicians?+
The disarm and render-safe approach differs by mechanism, a pressure plate, trip wire, and release switch each require a different handling method, and misidentifying the type risks accidentally triggering the device.
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