ABSTRACT
The loadbearing surfaces of the specimens (i.e. the faces in contact with the platens of the testing machine) shall not deviate from flatness by more than 0.1 mm per 100 mm.
Flatness can be checked across the diagonals, using a straight edge and a feeler gauge. Deviations shall be corrected by dry grinding, milling or a similar process. The dust of this process is removed.
