Proposed is a monitoring apparatus for a sanitary installation, comprising a first sensor for monitoring the presence of persons in a first spatial region in the surroundings of the sanitary installation and comprising a second sensor for monitoring a second spatial region in the surroundings of the sanitary installation, wherein the first sensor comprises an operating mode and a standby mode and the second sensor is embodied to switch the first sensor from a standby mode into an operating mode in the case of a predetermined detection. In order to avoid faults in the operating procedure, the first sensor is embodied as a distance sensor, in particular as a TOF sensor.