This International Standard describes, with reference to ISO/R 230, both geometrical and practical tests on general purpose and normal accuracy turret and single spindle co-ordinate drilling machines with vertical spindle and the corresponding permissible deviations which apply. It deals only with the verification of accuracy of the machine. It does not apply to the testing of the running of the machine (vibrations, abnormal noises, stick-slip motion of components, etc.), or to machine characteristics (speeds, feeds, etc.) which should generally be checked before testing accuracy. As there is great variety in the configuration of these machines, the most common being — box type and variable height table machines, — box type and fixed height table machines, — bridge machines, it is specified that the geometrical tests given in this International Standard shall be selected according to the particular conformation of the machine type considered.