An exhaust fan is a fan which is used to control the interior environment by venting out unwanted odors, particulates, smoke, moisture, and other contaminants which may be present in the air. Exhaust fans can also be integrated into a heating and cooling system. Common locations for exhaust fans include bathrooms and kitchens, and these fans are usually very easy to install, so they can be situated in many other locations as well. For installation, people do need a few tools, and they must be comfortable working with electricity to wire the fan in place.
A classic use for an exhaust fan is in an environment like a kitchen or a bathroom. These locations tend to get filled with steam, and steam can promote the development of mold, which is not desirable. An exhaust fan can be used to vent the warm, moist air to the outside, where it can disperse harmlessly. Exhaust fans can also vent cooking odors outside so that they do not linger indoors, and when people cook smoky foods, the fan can help keep the air in and around the kitchen clear.
For temperature control, an exhaust fan can be used in the hot months to push warm air outside, creating negative pressure inside the house. This promotes air flow by drawing in air from the outside, and the outdoor air may be cooler, contributing to cooling in the house. Using an exhaust fan can be an alternative to air conditioning, or a supplement to an air conditioning system.
These fans can also be useful in garages and workshops to ventilate the space. Since these areas can sometimes acquire strong smells and people may work with potentially dangerous chemicals in them, exhaust fans can be used for comfort and safety. An exhaust fan is especially important when people are working with things like solvents, which are not healthy or safe to inhale. Likewise, it is important to vent fumes from paints, varnishes, and similar types of treatments.
Such fans have uses outside the home as well. Any enclosed space can be vented with an exhaust fan, ranging from a large storage warehouse to a storefront. These fans are also used in settings like science labs to provide ventilation which will pull potentially hazardous substances away from people working in the lab. Similarly, they are used to vent operating rooms so that anesthetic gases are dispersed, and restaurants rely on heavy duty exhaust fans to keep their kitchens clear.