Grease duct - Simple English Wikipedia, the free encyclopedia

A grease duct is a duct that vents flammable vapors from commercial cooking equipment such as stoves and deep fryers to the outside of the building. It will normally be connected to an exhaust fan.

Vapors are created when grease is heated to and beyond its vaporization point. When it cools, the grease will condense on colder surfaces. Grease is a flammable hydrocarbon.

In many places, they will be constructed out of stainless-steel ductwork connected through a series of air filters which will be pulled by a fan and exhausted outside. They will also often have some form of fire damper in this ductwork connected to the fire alarm system. ^[1]

These systems must be cleaned sometimes. Many will have certificates issued by the cleaning^[2] and maintenance contractors.^[3]

Problems with hoods that are not taken care of include poor ventilation, excess heat and smoke, and the potential risk of fires.^[4][5]

Wikimedia Commons has media related to Category:Kitchen exhausts.

• UL treatise on wrapping systems
• NFPA 96: Standard for Ventilation Control and Fire Protection of Commercial Cooking Operations Archived 2013-05-02 at the Wayback Machine
• ASTM E2336 Standard Test Methods for Fire Resistive Grease Duct Enclosure Systems
• ISO 6944-1:2008 Fire containment -- Elements of building construction -- Part 1: Ventilation ducts