.This part of SS 728000 provides information on how to assess the severity of machine tool spindle vibrations measured on the spindle housing. The vibration criteria provided in this part of SS 728000 applies to spindles with integral drive intended for stationary machine tools with nominal operating speeds between 600 min-1 and 30 000 rpm-1. This part of SS 728000 only applies to spindles with rolling element bearing types. This part of SS 728000 provides specific guidance for assessing the severity of vibration measured on the spindle housing at customer site or at the machine tool manufacturer test facilities. This part of SS 728000 applies to spindles assembled in the machine tool. This part of SS 728000 is applicable for testing, periodic verification and continuous monitoring.Spindles with integral drive covered by this part of SS 728000 include spindle types intended for: — Machining centers — Milling machines — Boring machines — Grinding machines — Turning centers — Lathes — Turning machines. Spindles with bearing types other than rolling element bearings are excluded from this part of SS 728000. This part of SS 728000 does not address geometrical accuracy of axes of rotation (see ISO 230-7:2006). This part of SS 728000 does not address unacceptable cutting performance with regard to surface finish and accuracy. This part of SS 728000 does not address vibration severity issues of machine tool spindles operating at speeds below 600 min-1 or exceeding 30 000 min-1 due to lack of supporting vibration data and limitations in many vibration measurement instruments.