Similar to an ozone cleaner, an ionic air purifier also uses an electrical charge to alter oxygen atoms in the air. There is often confusion between ionic air cleaners and ozone air purifiers. The main advantage of the former is that an ionic air cleaner will not only clear your home of odors and mildew, but also purge your air of dust and pollen.

What are ion air cleaners, exactly, and how well do they work? The theory behind an ionic air purifier will take you back to your days in science class in high school. Most common household pollutants carry a positive charge. These are too light to settle on the ground or furniture, where they can be vacuumed or cleaned. They float about freely in the air that we breathe in our homes. What an ionic air cleaner does, is that it negatively charges the air particles in the room. Now, if you remember some high school science, you know that a positive charge and negative charge when brought close together will experience a magnetic attraction. And voila! As soon as the positively charged pollutant collides with the negatively charged anion, they bond together, becoming too heavy to remain airborne, and sink to the floor. Thus they are out of harms way and can no longer be inhaled. Regular vacuuming and dusting can get rid of these particles.

According to the U.S. Department of Agriculture, if properly used, these ionizers can lessen the amount of airborne dust in the room by over 50% and also diminish the airborne bacteria by 95%.

As compared to HEPA air filters, people who are concerned about noise pollution in their homes may prefer air ionizers as they are generally silent. HEPA air purifiers make more noise as they use a motorized fan to circulate the air to purify it. Ionic air purifiers, on the other hand, send out the ions or activated oxygen to purify the air, and hence are usually silent. Also, another advantage ionizers have over other purifiers is that its parts do not need regular replacement, as there are no physical filters. Even though most air ionizers don't have a motorized fan, the ionization creates a faint breeze that helps to distribute the ions throughout a room. Some are also outfitted with screens or prongs that catch the particles of dust as they fall to the ground.

Positive endorsements for the ionizer have come from many quarters. In an epidemiological study, it was found that repeated airborne infections of the bacteria acinetobacter in an ICU ward was totally wiped out with the installation of a negative air ionizer. Through the year long study, the infection rate fell to zero, disinfecting the air and thereby stopping the transmission of the infection.

Thus, keeping in mind your concern over noise, reliability and cost of purchase and maintenance, a low-cost ionic air purifier is a reasonably wise purchase.