ISO 8503-3:2012规定了光学显微镜，并描述了校准符合ISO 8503-1要求的ISO表面轮廓比较仪的程序。 它也适用于测定基本平面喷砂清理钢的表面轮廓，范围为20μm至200μm。可在喷砂清理后的基材的代表性截面上进行测定，如果无法直接观察表面，则可在表面的复制品上进行测定。

ISO 8503-3:2012 specifies the optical microscope and describes the procedure for calibrating ISO surface profile comparators conforming to the requirements of ISO 8503？1. It is also applicable to the determination of the surface profile, within the range of 20 μm to 200 μm, of essentially planar blast-cleaned steel. The determination can be carried out on a representative section of the blast-cleaned substrate or, if direct observation of the surface is not feasible, on a replica of the surface.