When we have a vibrating equipment, such as a centrifugal pump and we want to avoid that vibration affects the pipes to which it is connected or to the slab where it sits, it is best to use vibration isolating springs, however, sometimes it is not enough since there is an excess of “heavy” movement and this continues to be transmitted. The isolation of the vibration depends on the deflection of the spring, the disturbing frequency, and the total weight of the system. The first two are difficult to vary, but the weight of the system is easy, because if we add more mass to the system the vibrating part will lose percentage of importance in the system and the transmissibility will be lower, that is, the more weight we add to a system given, the smaller the magnitude of the transmitted vibration will be. And to easily add “mass” to the system, the best thing is a “base of inertia”, this is a steel structural base that can be filled with concrete to give extra “weight” to the system, we seek to give you with the base of 1 to 3 extra times the weight of the system. This complies with ASHRAE, book Applications, chap. 47, p. 47.45, note 30, type C, “Concrete Bases”.