Isolation refers to a reduction in transmitted vibratory forces or amplitude of motion.
This allows the inertia of the unit to oppose and thereby reduce the vibratory motion transmitted to the support. It must have the capacity to support the static weight of the unit as well as the unbalanced dynamic force. It must have a natural frequency lower than the offending unit's disturbing frequency. Static Weight of the Isolated Unit Isolator manufacturers have this information readily available in their publications. It depends on the desired percent reduction in transmitted vibration, referred to as transmissibility, and is governed by the ratio of disturbing frequency to isolator natural frequency.