Since that time, there has been a growth in the number of mobile devices with little or no user interface - including wrist bands, sensors and cameras – many of which are not able to display Warning Notifications. The recent growth in the number of IoT devices - not used by human users – also highlights the need for an alternative to text based Warning Notifications. If those devices can be made aware of the type of incident (. a fire or flood) in some other way than with a text message, then they may take preventive actions (. lift go to ground floor automatically).