Abstract: A single-barometer device, a method for fall detection and a system are provided. The single-barometer device worn on a user is used to measure multiple barometric values continuously by a barometer inside the device. The barometric values are stored in a memory of the single-barometer device. When a current barometric value is produced, the current barometric value is compared with a previous barometric value retrieved from the memory. A barometric difference can be obtained. The barometric difference is then compared with a threshold, and a comparison result is used to determine whether or not a fall event is present. The fall event is confirmed if the barometric difference is larger than the threshold. Further, an acceleration change obtained by an accelerometer inside the single-barometer device can be used to reconfirm the fall event.