<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (September 2009) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (September 2009) (Learn how and when to remove this template message) </Td> </Tr> <P> An exhaust hood, extractor hood, or range hood is a device containing a mechanical fan that hangs above the stove or cooktop in the kitchen . It removes airborne grease, combustion products, fumes, smoke, odors, heat, and steam from the air by evacuation of the air and filtration . In commercial kitchens exhaust hoods are often used in combination with fire suppression devices so that fumes from a grease fire are properly vented and the fire is put out quickly . Commercial vent hoods may also be combined with a fresh air fan that draws in exterior air, circulating it with the cooking fumes, which is then drawn out by the hood . </P> <P> In most exhaust hoods, a filtration system removes grease (the grease trap) and other particles . Although many vent hoods exhaust air to the outside, some recirculate the air to the kitchen . In a recirculating system, filters may be used to remove odors in addition to the grease . </P>

What is the purpose of an oven hood
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