This part of ISO 10791 specifies, with reference to ISO 230-1, the geometric tests for machining centres (or other numerically controlled machines, where applicable) with horizontal spindle (i.e. horizontal Z-axis).This part of ISO 10791 applies to machining centres having three numerically controlled linear axes (X-axis up to 5 000 mm length, Y-axis up to 3 200 mm length, and Z-axis up to 2 000 mm length), but refers also to supplementary movements, such as those of rotary, tilting, and swivelling tables. Movements other than those mentioned are considered as special features and the relevant tests are not included in this part of ISO 10791.This part of ISO 10791 takes into consideration in Annexes A through D four possible types of tables, fixed and rotary, as hereunder described:— Annex A: horizontal non-rotating tables;— Annex B: tables rotating around a vertical B’-axis;— Annex C: tables rotating around a vertical B’-axis and tilting around a horizontal A’-axis;— Annex D: tables rotating around a horizontal A’-axis and swivelling around a vertical B’-axis.This part of ISO 10791 does not consider accessory spindle heads, which are covered by ISO 17543-1:—1).This part of ISO 10791 deals only with the verification of geometric accuracy of the machine and does not apply to the testing of the machine operation, which should generally be checked separately. Tests not concerning the pure geometric accuracy of the machine are dealt with in other parts of ISO 10791, as listed in the Foreword.