Once a fan has been removed from the protective shipping container, it is important to properly handle fans. Some examples of improper handling are: dropping or knocking over onto a hard surface, applying excessive force to the fan frame, pushing or compressing the fan impeller. Fans should always be handled directly by the frame only. Note that it does not take much to damage a fan. Even if a fan is dropped, there may not be any physical indication of damage until the fan is in the field. If a fan is dropped or mishandled, Sanyo Denki recommends removing it from the product to prevent any issues that may arise later in the products life.