MIL-STD-2225, MILITARY STANDARD: VIBRATION AND NOISE TESTINGFOR INSTRUMENT BEARINGS (01 AUG 1994)., Vibration and noise measurements under controlled test conditions provide baseline data which can be used to ascertain relativebearing quality. The causes of vibration and noise are complex phenomena affected by many factors. This standard defines vibration and noise measurements under closely controlled conditions, and there is no guarantee that values measured in accordance with this standard will correlate with actual application.