This European Standard defines a method of microscopic non-metallic inclusion assessment using picture charts. The method does not apply to particles of a length less than 3,0 µm or a width smaller than 2,0 µm. Defined by a product standard or agreement between the involved parties for certain special products, inclusions with a width below 2,0 µm can only be evaluated according to their length. Elongated inclusions with a length above 1 410 µm are counted separately and are beyond the upper application limit of this standard. Globular inclusions with a diameter of 3,0 µm and above are included in the assessment. It is assumed, if particles are elongated or if there are stringers of particles, that they are parallel to each other. Other arrangements are not covered by this standard. This European Standard applies to samples with a microscopic precipitation approaching random distribution. From the data of measurements obtained by this method, evaluation according to other standards can be established. This European Standard does not apply to free cutting steels. NOTE The basic principle of this European Standard allows the determination of non-metallic inclusion content by image analysis techniques.