noise emissions which have been analyzed using stored threshold values and or stored noise patterns as regards the apparatus for determining a leak in at least one installation component and or a state of at least one installation component of an installation at least one optical recording unit for monitoring a subregion of one or more installation components is provided wherein one or more acoustic recording units is or are arranged in the region of at least one of the installation components and can be used to detect analyze and locate any noise emissions occurring wherein the optical recording unit can be controlled in such a way that it additionally detects optically and analyzes acoustically located noise emission regions of the installation component in question expediently the at least one acoustic recording unit and or the optical recording unit are connected to an evaluation unit as an alternative the evaluation unit can be an integral part of the acoustic or optical recording unit expediently the acoustic recording unit is an acoustic pickup in particular an acoustic transducer for example a microphone another suitable means for recording the sound waves of the noise emissions can be provided which converts the detected sound waves into a usable electrical signal the optical recording unit is preferably a camera or another suitable apparatus such as an infrared camera a radar unit an omnidirectional camera a stereo camera for example in.