Kitchen exhaust fans are recommended for all kitchens, whether they are in residential homes or commercial enterprises. There are a number of different kitchen exhaust fans to choose from; they include the simple exhaust fan which is mounted in a wall or ceiling, range hoods and commercial exhaust systems.
Kitchen ventilation is a necessity as it is important to vent humidity from steam and cooking odors as well as air borne grease. Although in a domestic environment the greatest amount of humidity comes from boiling water on the stove top, it also comes from washing dishes with hot water. In those homes and commercial establishments where gas is the fuel of choice, it is also important that carbon monoxide fumes are also eliminated. There is also the issue with odors that must be eliminated and the most efficient way to do this is to pull them out with some sort of exhaust fan.
In many kitchens the owner will install either a ceiling mount exhaust fan or a wall mounted unit. In the case of a ceiling mount fan it is important that it be ducted outside whereas a wall mounted unit can fit neatly into a preformed cavity in the wall. There are many different sizes of these fans available, small units are preferred for the home while commercial kitchens will have significantly larger units.
A range hood is another type of kitchen exhaust fan. In this case a hood which has an integral exhaust fan is mounted above the cooking surface. When the fan is engaged the steam, grease and odors are pulled into the hood and then vented outdoors through a duct. This is the ideal way but there are also range hoods that are not vented, they filter the air which is then returned to the kitchen. This type of range hood is often preferred when the cooking surface is located against an interior wall and ducting is difficult.
Industrial kitchens such as those found in canteens, restaurants, hospitals, etc have all the same problems; just bigger. There is a huge amount of heat and steam generated in an industrial kitchen as well as a large amount of grease. In these cases the solution lies with a combination of devices. Normally there is a full length hood that spans all the cooking appliances, through one or more outlets the moisture, odors and grease are pulled out with the use of large industrial duty roof mounted centrifugal fans which are equipped with grease filters and dampers.
Regardless of the size of the kitchen, the fuel that is used or the location of the appliances there is a way to exhaust the hot, damp and odorous air.