Patent ID: 8604799

Claim:
A method for detecting at least one of damaged points, faulty points, and weak points having a reduced material thickness in a membrane-type, electrically non-conductive or poorly conductive structural seal having a high electrical disruptive strength by comparison with air and that is provided with a first electrically conductive layer, the first electrically conductive layer being arranged inside or outside the structural seal and extending over substantially the entire surface of the structural seal and to which an electrical test voltage is applied, the method comprising: providing a second electrically conductive layer, which is electrically separated from the first electrically conductive layer by the structural seal and extends over substantially the entire surface of the structural seal; selecting a level of the electrical test voltage between the electrically conductive layers in such a way that, if there exists at least one of a damaged point, faulty point and weak point in the structural seal, an electrical disruptive strength is exceeded and an electric spark or arc is formed at the location of at least one of the damaged point, the faulty point and the weak point; and applying the electrical test voltage between the electrically conductive layers, wherein the electrical test voltage is selected to be smaller than a destructive test voltage at which an electrical breakdown accompanied by the formation of an electric spark or arc would occur in at least one of an undamaged structural seal and an un-weakened structural seal corresponding to the structural seal to be tested.