The PureAir and PureAir S systems reduce concentrations of pollutants through a process called photocatalytic oxidation (PCO). Similar to the process used by the Department of Defense to combat germ warfare, PCO combines nature's three most powerful air purifiers:

1. Ultraviolet light
2. Titanium dioxide, a nontoxic substance found in the earth's crust
3. Hydroxyl radicals, particles derived from hydrogen peroxide

The PureAir PCO process involves three steps:

1. The pleated media filter captures particles and bioaerosols like pollen and pet dander, removing them from the airstream.
2. As the odor- and chemical-filled airstream flows over the UVA light, the airstream is exposed to the catalytic surface (titanium dioxide-coated mesh filter).
3. The light energy activates the catalyst, which generates hydroxyl radicals. These particles, which are more than twice as powerful as chlorine, break down the odors and chemicals into carbon dioxide and water.