Vibration, by causing loosening of parts or relative motion between parts in the specimen, can produce objectionable operating characteristics, noise, wear, and physical distortion, and often results in fatigue and failure of mechanical parts.

Vibration testing is used to determine the effects on component parts of vibration within the predominant frequency ranges and magnitudes that may be encountered during field service and/or transportation. Most vibrations encountered in field service and/or transportation are not of a simple harmonic nature, but tests based on vibrations of this type have proved satisfactory for determining critical frequencies, modes of vibration and other data necessary for planning protective steps against the effects of undue vibration.

Random Vibration is characteristic of modern field environments such as commercial transportation, those produced by missiles, high-thrust jets and rocket engines. In these types of environments, the random vibration provides a more realistic test as it simulates vibration amplitudes which may vary randomly, periodically, or both.