PURPOSE This vibration fatigue test is performed for the purpose of determining the ability of component parts and their mountings to withstand vibration in the low frequency range of 10 to 55 Hertz. As it is . not practical to test components for vibration under actual operating conditions@ this set of accelerated laboratory tests was devised to simulate vibration conditions m6re severe than those normally encountered in fixed@ land mobile@ and marine installations. A component part is considered to be faulty if during or after vibration testing it exhibits objectionable operating characteristics@ noise wear@ physical distortion or degradation of mechanical properties which would result in the unit not meeting the performance requirements of the applicable individual specification.