Information on Home Air Purifiers

The Facts

• The purpose of a home air purifier is, in essence, to remove impurities from the air inside the home. The various methods of removing impurities depend on the impurities to be removed, as different types of particles require different techniques to filter them out. Although some air purifiers claim to provide health benefits, research on their effectiveness is limited.

Anti-bacterial Air Purifiers

• Two of the four types of air purifiers attempt to filter out bacteria and microorganisms. Ultraviolet purifiers pump air through a beam of ultraviolet light, which floods the bacteria with radiation in an attempt to kill them. Similarly, ozone air purifiers filter the air through ozone, an unstable molecule made from three oxygen atoms. Bacteria absorb the ozone, with most dying as a result. As a byproduct, many odors are neutralized by reacting with ozone.

Filtration Air Purifiers

• Two of the four air purifier types filter some, or even most, allergens out of the air. Ionic air purifiers instill an electric charge in the air surrounding themselves, which they then use to attract nearby particles. This acts as a filter that removes some forms of allergens, such as pollen, from the air. HEPA purifiers instead filter the air through a cloth mesh in a similar method to a vacuum cleaner.

Warnings

• Some air purifiers reduce the amount of allergens in the air and may therefore help to relieve the symptoms of allergy sufferers, but this is by no means a guarantee. "Guide to Air Cleaners in the Home," the U.S. Environmental Protection Agency's report on air cleaners, states that "evidence is weak" regarding the ability of air purifiers to help alleviate the causes of asthma attacks.