In the recent past, high-pressure pipelines have been, independent of the medium which is transported by them, used in a more and more optimal way as far as their remaining life is concerned. A large number of the pipeline operators have handled the pipelines in a different way in recent years. The maintenance costs for transmission pipelines have been reduced more and more. Where in earlier times a rehabilitation or reconstruction of pipe-lines already occurred in case of slight impairments, for example by corrosion, nowadays the weak point or damaged spot will be left in the pipeline, provided that it does not influence the basic stability of the pipeline. For this, suitable tools were developed in the past in order to prove the integrity of the pipeline also for such cases. It must be guaranteed that the quality of the transmission pipeline does not fall below a certain minimum. In this case, it is distinguished between an absolute minimum and a relative minimum defined by the safety philosophy of the operator.