This document specifies, with reference to ISO 230-1, ISO 230-2 and ISO 230-7, geometric tests and tests to check the accuracy and repeatability of positioning of numerically controlled axes for general-purpose, normal accuracy bridge-type milling machines with a travelling bridge (gantry-type). This document also specifies the applicable tolerances corresponding to the above-mentioned tests.

This document provides the terminology used for the identification of the principal components of the relevant machine tools and the designation of axes with reference to ISO 841.

This document is applicable to machine tools with travelling bridge and fixed table. This document does not include single-column (open-sided) machine tools and those with fixed bridge and moving table.

This document deals only with the verification of the accuracy of the machine tool. This document does not apply to the testing of the machine tool operation (vibration, abnormal noise, stick-slip motion of components, etc.) nor to machine tool characteristics (such as speeds and feeds), which are generally checked before testing the accuracy.