Embodiments of the invention provide a venturi valve and control system for use in an indoor environment to regulate air flow. The venturi valve includes a substantially cylindrical pipe, a high pressure sensing assembly, a low pressure sensing assembly, a differential pressure transducer, and a damper assembly. The high pressure sensing assembly and the low pressure sensing assembly do not substantially impede air flow through the valve. A controller is connected to the differential pressure transducer and a damper actuator. The controller determines a current flow rate of air into the indoor environment and operates the damper actuator in order to provide a desired flow rate of air into the indoor environment.

A vacuum generator including a cluster of multi-stage venturi cells, each having a nozzle which is sealingly secured in an inlet orifice of a first mixer provided with a first suction orifice, and a second mixer fixed to the first mixer in such a manner that the second mixer extends coaxially to the first mixer and is spaced apart from an outlet orifice of said first mixer in order to form with the same a second suction orifice, characterized in that the first mixers are firmly interconnected by a first frame extending between the first suction orifices and the outlet orifices of the first mixers to form a first sealing surface surrounding said first mixers, and the second mixers are firmly interconnected by a second frame extending between the inlet orifices and the outlet orifices of the second mixers to form a second sealing surface surrounding said second mixers.