VIBRATION T ISOLATION THEORY he choice of vibration isolators must take many factors into consideration. Some of them are the vibration disturbing frequency and amplitude, the mass of the suspended system, the isolator static deflection and effective spring rate and the criticality of the location. There are many fine independent acoustical consultants who, with the help of specialized equipment, are able to pinpoint exactly what is required to solve any specific problem. One of the most important factors when determining the efficiency of a system is the static deflection of the isolators. The static deflection is how much the isolators compress under the weight of the equipment. The greater the static deflection, the greater the isolation efficiency (see the chart below). It is therefore very important to choose isolators that will provide the maximum static deflection for the load to be supported. Choosing isolators for a much greater load to be " safe " will result is a less efficient system. The maximum recommended steady loads shown are not failure points, but represent loads that, when exceeded for long periods of time, may cause the isolator to take a " permanent set " there-by reducing the efficiency of the system. % ISOLATION EFFICIENCY 99 97 95 90 85 80 70 60 RESONANCE NATURAL FREQUENCY CYCLES PER MINUTE CYCLES PER SECOND VIBRATION AND NOISE DISTURBING FREQUENCY STATIC DEFLECTION IN INCHES