There are more fans at work in indoor air spaces than you may realize, with many purposes from home use to industrial. The most obvious fans are the portable ones around the house that keep you cool in the heat, and ceiling fans that circulate air. An exhaust fan above the stove typically keeps your kitchen from getting smokey, and a chimney fan has the same purpose. A fan in your bathroom keeps it from filling up with steam from a hot shower. If you need to install a bathroom fan, figure out the volume of the room and divide it by five; this will give you the size of fan you will need.
Exhausto fans are high tech and can save money in a home or restaurant settings in a variety of ways. Despite higher initial purchase and installation costs, a fan that consumes less energy and lasts longer will be a sound investment. Using an energy efficient fan while raising air conditioning by 3 degrees has been shown to cut energy costs by 12-15%, which can end up being quite a lot of savings in hot summer months.
Restaurants can benefit greatly from exhausto fan systems, though some of the benefits of an expensive renovation may not be immediately felt. Many large walk-in freezers use antiquated fan systems, and efficient fan motors can reduce energy costs, by about $200 per year. This savings may not be felt immediately, depending on how much was spent to install them.
Restaurants and other large businesses typically also need air filtration and circulation, which can either be a system that recirculates air a certain regulated amount, or vents the exhaust to the outside. A laminar fan circulates air 300 times per hour, and is typically used in hospitals. Indoor air quality is very important and may be tested more often as our awareness of it grows.