Code black
Code black is the standard Australian hospital emergency code for a personal threat: an incident of violence or aggression requiring an immediate response.
Hospitals run on colour codes - red for fire, blue for medical emergency - and black is the one for people: an armed threat, a violent patient, an assault in progress, a staff member in danger. Calling a code black mobilises security and trained responders to a location, fast.
The weak point in many code black systems is the trigger. Wall-mounted duress buttons assume the incident happens near a wall; overhead announcements assume the worker can reach a phone and speak. Wearable duress devices close that gap: a nurse pinned in a bed bay or a clinician in a car park can raise the alarm silently, with their exact location attached.
Beyond hospitals, the same pattern appears wherever teams formalise aggression response: corrections, emergency departments, mental health units, and increasingly community settings where the responder is a monitoring centre rather than on-site security.