An exhaust hood is a ventilation system component that removes contaminated air, moisture, and odors from an indoor space and expels them outdoors. Exhaust hoods are fundamental to HVAC systems in commercial kitchens, bathrooms, laboratories, and industrial facilities. They function as capture devices that pull air away from source pollution areas and direct it through ductwork to the exterior.
Technical Details
Exhaust hoods contain fans powered by electric motors that create negative air pressure, typically operating between 500 to 2,000 CFM in commercial kitchen applications. The hood design includes a capture area sized proportionally to equipment dimensions, with sufficient face velocity typically ranging from 60 to 100 feet per minute for cooking equipment. Most commercial exhaust hoods incorporate dampers to prevent backflow and outdoor air infiltration when fans are inactive.
Applications
Exhaust hoods are standard in commercial kitchens above all cooking equipment, in bathrooms for moisture control, and in laboratories for hazardous vapor removal. Residential kitchen exhausts typically operate at 150 to 400 CFM depending on cooktop size and cooking intensity.
Practical Significance
Effective exhaust hood operation reduces indoor humidity, prevents mold growth, eliminates cooking odors, and maintains code compliance. Proper sizing and installation ensure adequate air removal while minimizing energy consumption and noise levels.