This nationally adopted international standard is applicable to land-based gas turbines, steam turbines and generators (whether coupled with gas and/or steam turbines) with power outputs greater than 40 MW, fluid-film bearings and rated speeds of 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min. The criteria provided in this document can be applied to the vibration of the gas turbine, steam turbine and generator (including synchronizing clutches). This document establishes provisions for evaluating the severity of the following in-situ, broad-band vibration: a) structural vibration at all main bearing housings or pedestals measured radial (i.e. transverse) to the shaft axis; b) structural vibration at thrust bearing housings measured in the axial direction; c) vibration of rotating shafts radial (i.e. transverse) to the shaft axis at, or close to, the main bearings.