This European standard specifies a method for the determination to intergranular corrosion of austenitic stainless steels in a sulphuric acid/copper sulphate medium in the presence of copper turnings (Monnypenny Strauss test). The method is applicable only to austenitic stainless steels supplied in the form of cast, rolled or forged products and tubes and intended to be used in a mildly oxidizing acid medium (for example sulphuric or phosphoric acids).