This part of ISO898 specifies a torsional test for the determination of the breaking torque of bolts and screws with nominal diameters 1mm to 10mm with property classes 8.8 to 12.9 in accordance with ISO898-1. The test applies to bolts and screws with thread less than M3 for which no breaking and proof loads are indicated in ISO898-1, as well as to short bolts and screws with nominal diameters 3mm to 10mm which cannot be subjected to a tensile test.
The minimum breaking torques are not valid for hexagon socket set screws.