Industrial on-demand exhaust ventilation system with closed-loop regulation of duct air velocities

A closed-loop regulation method of a ventilation system using a control computer. The method includes the steps comprising: providing a ventilation system with a control computer, an exhaust fan, sensors, and gates; using the sensors to determine actual air velocities within the ventilation system; providing minimum air velocities that must be maintained throughout the ventilation system; monitoring the one or more air velocities; and maintaining by the control computer that the actual air velocities are above the one or more minimum air velocities. Preferably, the ventilation system includes a control computer that takes the measurements, makes the air flow calculations, and automatically adjusts the gates and fans to ensure that a minimum air velocity is kept in all parts of the ducts of the system. Preferably, the ventilation system is energy efficient by optimizing the air flow and lowering the amount of energy needed to run the system.