scope:

NEN-EN-ISO 6789-2 specifies the method for the calibration of hand torque tools and describes the method of calculation of measurement uncertainties for the calibration. This document specifies the minimum requirements for the calibration of the torque measurement device where the relative measurement uncertainty interval, W´md, is not already provided by a traceable calibration certificate. ISO 6789 is applicable for the step by step (static) and continuous (quasi-static) calibration of torque measurement devices, the torque of which is defined by measuring of the elastic form change of a deformable body or a measured variable which is in proportion to the torque. This document applies to hand torque tools which are classified as indicating torque tools (Type I) and setting torque tools (Type II).