Mechanical ventilation is the use of a mechanical device (machine) to inflate and deflate the lungs.

They have mechanical ventilation.

Mechanical ventilation is ordered for patients in acute respiratory distress, and is often used in an intensive care situation. In some cases, mechanical ventilation is a final attempt to continue the breathing function in a patient.
Mechanical ventilation may be required only at night, during limited daytime hours, or around the clock, depending on the patient's condition. Some patients require mechanical ventilation only for a short period,

Passive ventilation is a system of ventilation which requires no mechanical parts. for example, one could ventilate a room using a powerful exhaust fan, and that would be mechanical ventilation. Or one could simply open a couple of window's that would be passive ventilation.

A building management system is a computer-controlled system that controls all aspects of a building that are mechanical or electrical. Examples include ventilation, lighting and security systems.