A device management system comprising: one or more devices; a control system connected to the one or more devices to be ready to communicate with the one or more devices, wherein each of the one or more devices are configured to detect a presence of an event that calls for disaster prevention measures; wherein each of the one or more devices comprises: detection units (32, 33, 34, 35) configured to output detection signals indicative to an internal event, the internal event including at least one of a timing to replace the device, a malfunction of the device, a low battery level of the device, dirtiness of the device, and an abnormal temperature inside the device, a control unit configured to monitor the detection signals output from the detection units (32, 33, 34, 35) and determine, based on the detection signal, whether or not the internal event has occurred; a communications unit configured to transmit device information about the detection signals at regular intervals to the control system; and an altert unit configured to emit light or a sound alerting a user to the internal event when the determination is made by the control unit that the internal event is happening to the device wherein the control system comprises: an acquisition unit configured to acquire device information from the one or more devices; a decision unit configured to determine, based on the device information and before the determination is made by the control unit that the internal event is happening to the respective device, whether or not the device shows any early signs of the internal event; and an output unit configured to output to an external server or telecommunications device owned by the user of the one or the plurality of devices, early signs information about any early signs of the internal event, the early signs information including a decision made by the decision unit and being based on the device information. one or more devices; a control system connected to the one or more devices to be ready to communicate with the one or more devices, wherein each of the one or more devices are configured to detect a presence of an event that calls for disaster prevention measures; wherein each of the one or more devices comprises: detection units (32, 33, 34, 35) configured to output detection signals indicative to an internal event, the internal event including at least one of a timing to replace the device, a malfunction of the device, a low battery level of the device, dirtiness of the device, and an abnormal temperature inside the device, a control unit configured to monitor the detection signals output from the detection units (32, 33, 34, 35) and determine, based on the detection signal, whether or not the internal event has occurred; a communications unit configured to transmit device information about the detection signals at regular intervals to the control system; and an altert unit configured to emit light or a sound alerting a user to the internal event when the determination is made by the control unit that the internal event is happening to the device detection units (32, 33, 34, 35) configured to output detection signals indicative to an internal event, the internal event including at least one of a timing to replace the device, a malfunction of the device, a low battery level of the device, dirtiness of the device, and an abnormal temperature inside the device, a control unit configured to monitor the detection signals output from the detection units (32, 33, 34, 35) and determine, based on the detection signal, whether or not the internal event has occurred; a communications unit configured to transmit device information about the detection signals at regular intervals to the control system; and an altert unit configured to emit light or a sound alerting a user to the internal event when the determination is made by the control unit that the internal event is happening to the device wherein the control system comprises: an acquisition unit configured to acquire device information from the one or more devices; a decision unit configured to determine, based on the device information and before the determination is made by the control unit that the internal event is happening to the respective device, whether or not the device shows any early signs of the internal event; and an acquisition unit configured to acquire device information from the one or more devices; a decision unit configured to determine, based on the device information and before the determination is made by the control unit that the internal event is happening to the respective device, whether or not the device shows any early signs of the internal event; and an output unit configured to output to an external server or telecommunications device owned by the user of the one or the plurality of devices, early signs information about any early signs of the internal event, the early signs information including a decision made by the decision unit and being based on the device information.