Abstract: The present invention relates to an annular barrier (1) to be expanded in an annulus (2) between a well tubular structure and an inside wall (4) of a borehole (5) downhole, comprising a tubular part for mounting as part of the well tubular structure, said tubular part (6) having a longitudinal axis; an expandable sleeve (7) surrounding the tubular part and having an outer face (8), each end (9, 10) of the expandable sleeve being fastened to the tubular part by means of a connection part (12), where one of the connection parts is a sliding connection part sliding in relation to the tubular part when the expandable sleeve is expanded; an annular barrier space (13) between the tubular part and the expandable sleeve; an aperture (11) in the tubular part for letting fluid into the annular barrier space to expand the sleeve; and an activatable shut-off valve (14) having an open and a closed position and arranged in the aperture, wherein the annular barrier further comprises a detection device (20) for detecting whe