To calculate vibration from generators and transformers affecting a building's structure, it's important to consider the resonant frequencies of the building, which may align with the equipment's vibrations. Vibration isolating mounts should be used for the equipment to mitigate these effects. Induction motors typically operate at speeds with about 5% slip, and unbalance vibrations can be expected within a frequency band of ±5% of the motor's design speed. Additionally, vibrations from motors will occur at their RPM frequency, while load imbalance vibrations depend on the pulley diameter ratios. Transformers generate vibrations due to magnetostriction, producing a buzz at twice the fundamental frequency, such as 100Hz for 50Hz supplies and 120Hz for 60Hz supplies.