A vibration isolator may be unsuitable for many reasons. The most obvious reason is failing to match the isolator’s deflection with the required natural frequency to achieve the necessary level of vibration isolation. In many cases, rubber or other layer material ‘vibration isolators’ are used when the limited deflection they provide means that they will be close to resonance at the equipment’s operating speed. This results in a slight amplification of the vibrational energy, rather than any isolation being achieved.