Abstract: The specification discloses an exhaust ventilation system with a vented hood arrangement over a cooking area which is controlled automatically by the presence of a cook at a cooking station. The primary exhaust fan is automatically turned off a predetermined period of time after the cook has left the cooking station. A fresh air fan is similarly controlled by the presence of the cook at the cooking station. An auxiliary exhaust fan is automatically energized and deenergized in response to the operation of the primary exhaust fan, such that the auxiliary fan is on when the primary exhaust fan is off and vice versa.