Air cleaning can be used to reduce indoor air pollutants. Air cleaning is a technique generally used in conjunction with source removal and ventilation strategies. Air cleaners will not removes all types of pollutants and air cleaning alone cannot adequately remove all pollutants typically found in indoor air. Pollutants that can be effectively removed by air cleaners include:
• dust 
• pollen 
• dander
• dust mite residue
• bacteria 
• viruses 
• most airborne particles
(Note: not all air cleaners are equally effective in removing different pollutants) 

Some air cleaners may be installed in the ducts that are part of the home central heating or air-conditioning system. Portable air cleaners stand alone in a room. 

Types of air cleaners include:
• Mechanical filters, similar to and including the typical furnace filter;
• Electronic air cleaners (for example, electrostatic precipitators), which trap charged particles using an electrical field;
• Ion generators, which act by charging the particles in a room. The charged particles are attracted to walls, floors, and draperies or to a charged collector.
• "Hybrid" devices, which contain two or more of the particle removal devices discussed above.

Air cleaners can be mounted on the home heating and air conditioning system and clean the air in the entire home or they can be portable units, typically used to clean the air in one room. Your Indoor Air Alliance Technician will recommend a type of air cleaner to suit the needs of your home based on the results of the Healthy Home Screening described in the Programs and Services section.

Additional Factors To Consider

1. Ion generators and electronic air cleaners may produce ozone, particularly if they are not properly installed and maintained. See the U.S. EPA report on ozone in air cleaners (http://www.epa.gov/iaq/pubs/ozonegen.html).

2. Ozone can be a lung irritant.

3. Gases and odors from particles collected by air cleaning devices may be re-dispersed into the air.

4. Tobacco smoke odor is due largely to gases in the smoke, rather than particles. Thus, you may smell a tobacco odor even when the smoke particles have been removed.
5. Some devices scent the air to mask odors, which may lead you to believe that odor-causing pollutants have been removed.

6. Ion generators, especially those that do not contain a collector, may cause soiling of walls and other surfaces.

7. You may be bothered by noise from portable air cleaners, even at low speeds.

8. Maintenance costs, such as replacement costs for filters, may be significant. Consider these costs in addition to the initial cost of purchase. In general, the most effective units are also the most costly.

Air Cleaners and Ductwork Cleaning

If the ductwork environment in your home is contaminated, IAA suggests that you have this problem solved before purchasing or installing an air cleaner. Contaminated ducts will add to the levels of dust and particulates in the air. These particulates will clog up an air cleaner and can dramatically reduce its effectiveness. Cleaning ductwork as needed and then installing an air cleaner is generally the best solution.