RFID tags on every instrument + RFID wristbands on each technician identify who picked up what. A soap sensor at the wash station confirms a hand-wash event. Cameras at the bench and wash station provide a second confirmation layer and supply the evidence clip on violation. A deterministic state machine — not ML inference — evaluates the sequence and triggers alerts. The protocol logic is a simple three-state machine: idle → holding → wash-window → idle (clean) / violation.