An extractor hood consists of three main components: a skirt or capture panel to contain the rising gases (also known as the "effluent plume"), a grease filter, and a fan for ventilation.
A ducted system removes of all forms of airborne contamination, while a ductless one recirculates heat and moisture.
In addition, a ducted application eliminates the need for regular replacement of the filters and avoids the airflow restriction (and the resultant loss of power) caused by them.
However, the ducted application can be impractical, due to lack of space or ability to install a duct system, make-up air requirements, or the additional cost of heating or cooling the make-up air.
Extractor hoods with electronic controls can offer remote control, motorized height adjustment, thermal sensor, overheat protection, boost mode, delayed shut-off, filter cleaning reminder, active noise cancellation, temperature display, user presets (memory), and so on.
Extractor hoods may be made from a variety of materials, including stainless steel, copper, bronze, nickel silver, zinc, tempered glass, wood, aluminum, brass, heat-resistant plastics, and more.
NFPA 96 Standard for Ventilation Control and Fire Protection of Commercial Cooking says that mesh filters shall not be used.
Large sized duct hoods are widely used not just in homes but also in commercial restaurants and communal kitchens too.