Abstract: The described invention relates to a computer-implemented method for determining fire safety and occupant safety information, comprising: receiving data from a plurality of Appliances, each equipped with thermal sensors, carbon dioxide detectors and real-time voice communication capabilities, arranged within a building and configured to detect locations of elevated temperature and ambient carbon dioxide levels within the building; wherein one or more of said Appliances are arranged to detect elevated temperatures and levels of carbon dioxide indicative of the presence or risk of fire, and one or more of said Appliances are arranged to detect elevated temperatures indicative of body heat and carbon dioxide levels indicative of respiration and therefore the presence of one or more people, and enabling communication between occupants and a remote person to determine any special medical priorities of said occupants; analysing the received data to determine a first location corresponding to the presence or risk of