A grease duct is a duct that is specifically designed to vent grease-laden vapors from commercial cooking equipment such as stoves, pizza ovens, deep fryers and woks to the outside of a building or mobile food preparation trailer. Grease ducts are regulated both in terms of their construction and maintenance, forming part of the building's passive fire protection system. Even the cleaning schedule is typically dictated by the fire code and evidence of compliance must be kept on file by the owner.
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