tion. To the best of our knowledge, this paper is the first real-world implementation of the SensorThings API (STA) and IndoorGML. In order to validate the IoCT, an integrated COVID-19 solution was deployed and evaluated to monitor and analyze the risks of COVID-19 transmission in workplace reopening. For example, the following criteria may increase the risk of COVID-19 spread in an office room: If the room was used and the density of people was not regulated; if a sick p