Human presence detection by monitoring the indoor CO2 concentration

Presence detection systems are becoming more and more important and are used in smart home environments, in the Ambient Assisted Living (AAL) domain or in surveillance technology. Common systems focus on using motion sensors or cameras, which have only a limited viewing angle and therefore monitoring gaps can easily occur within a room. Humans produce carbon dioxide (CO2) through their respiration, which is distributed in rooms. As a result, if one (or more) persons are in a room, a significant increase in CO2 concentration in the room can be noted. With this work we investigate an approach to detect the presence or absence of people indoors by monitoring the CO2 concentration in the ambient air.