- Mechanical strength on impact with a steel ball Tests for the nature of destruction
- Resistance to mechanical impact with a soft body (protection class)
- Geometric dimensions
- Thickness
- The presence of cracks, chips, cracks on the edges and damage to the corners
- Appearance (defects) and color
- Deviation from flatness
- Deviation from the straightness of the edges
- The difference in the lengths of the diagonals
- The location of holes, grooves, cutouts
- Marking control