This project in a joint effort by the Faculty of Engineering, Faculty of Medicine, industrial companies and independant colaborators. This mechanical ventilator is intended for invasive ventilation. It works in pressure regulated volume control (PVRC) mode which is a continuous mandatory ventilation (CMV) type. It uses pneumatic parts used in the food processing industry, which require special certification but are commonly available. Air and gas are mixed in a container to the required FiO2. The cycle frequency is controlled by turning on and off pneumatic directional valves so the flow is directed into the patients lungs or out. A combination of pressure regulated valve and an air nozzle allows to control flow rate. The tidal volume is controlled by the opening time interval of the inlet valve. The expiratory branch has a peep valve as well as second pneumatic valve to direct the flow out at the required peep pressure.