To help keep personnel working in high-threat environments safe, the Flash™ emergency alarm system instantly sends a call for help at the touch of a button. When a user causes an alarm by activating his / her Personal Protection Device (PPD) the PPD emits an RF signal that is picked up by Flash sensors installed in wall or ceiling spaces. The Flash sensors in turn signal the alarm condition to the central control computer running Flash user-interface software. The alarm and PPD is displayed to security personnel.