Emporia Telecom: The emergency service button

In episode 7 of the Emporia Telecom video series, Ian Hosking, Senior Research Associate at the Engineering Design Centre, University of Cambridge, explains how the emergency button works on Emporia handsets. The key issue here is that it's not just a serial dialler -- that's no use if your primary contact's voicemail answers. What's the solution? Ian explains in this video.