There are three methods to reduce pollutants in indoor air. In order of effectiveness, these are:

• The removal of the source of the emission
• Ventilation
• Air cleaning

Air cleaning can be used as an adjunct to source control and ventilation, but alone it cannot effectively remove all the pollutants typically found in indoor air.

Many factors need to be considered in determining whether using an air cleaner is appropriate. There are also several different types of air cleaners on the market. Air cleaners can be part of the central heating/air-conditioning system or they can be portable. The various types of air cleaners also need frequent cleaning and filter replacement to work properly. It is best to consult a professional HVAC contractor to assist with selection, installation, and maintenance of such devices.