A sensor for physiological measurement comprising at least one detector configured to acquire a signal indicative of a vital sign of a subject. The sensor further comprises at least one state indicator configured to indicate one of at least two different ranges based on the signal acquired by the at least one detector, wherein the ranges are a first range and a second range, wherein the first range is for one of desired vital sign signals and minor alarming vital sign signals, and the second range is for vital sign signals outside the first range.
