The Exhaust Duct is a component of a ventilation system that carries contaminated air from a commercial kitchen to the outside of the building. It connects the exhaust hood to the roof or sidewall of the building and consists of a series of metal ducts, elbows, and other fittings that transport the air. The exhaust duct also includes a fan that creates negative pressure, pulling the contaminated air out of the kitchen and through the ductwork. Proper installation and maintenance of the exhaust duct are critical to the efficient operation of a ventilation system and the safety of the building. Regular cleaning of the Exhaust Duct is necessary to prevent the buildup of grease and other contaminants, which can lead to fire hazards and other safety risks.