There are no effectiveness standards for air purifiers sold on the consumer market. Because scientific testing is expensive and is not required, manufacturers simply don't do it before they bring their product to market. Please see the informative article written by Frank Hanes, President of IQAir, North America entitled "The Seven Sins of Air Filter Manufacturers". Mr. Hanes's article describes clearly the problems that exist when there are no industry concentration level standards for specific air pollutants. The marketplace is full of machines that sell, but either make no difference in air quality or make it worse. There is a huge unmet market for effective air purifiers.
Other air filters claim to capture many different pollutants. But since they don't list concentration levels, consumers have no way of knowing how much of each pollutant is in the "clean air." Unfortunately, that's the very information they need the most. The concentration level of a gas or paticulate is what can make the difference between an innocuous dose and a harmful dose.
The following are examples of the technology that our competitors use:
- Ionizers and other electrical approaches to cleaning particles from vehicle cabin air. These are low cost, quiet operation, small footprint, and no filter media requiring replacement. The disadvantages are unknown or minimal processing of dirty air by the device, creation of ozone when charged particles snap onto a plate with the opposite charge, frequent cleaning required of the charged plates, and possible interference with a vehicle's electrical system as evidenced in patents.
- Ozone generators that are sold as air cleaners and intentionally produce ozone gas. Some manufacturers or vendors suggest that ozone will render almost every chemical contaminant harmless by producing a chemical reaction whose only by-products are carbon dioxide, oxygen and water. Because of suspected health concerns associated with ozone, US-EPA conducted a thorough study of available scientific data. They concluded that, at concentrations that do not exceed public health standards, ozone does not effectively remove indoor air contaminants, odor-causing chemicals, or biological pollutants such as bacteria and mold.
- Carbon impregnated fiber filters which supposedly capture gasses. The CIFs offer the advantage of being inexpensive; additionally, they allow claims of capturing "some odors" and they provide structure. The disadvantages are: unknown effectiveness against the most harmful gasses; limited useful life compared to granular or palletized carbon (because less carbon is in carbon impregnated fiber filters and there are fewer available carbon pores since some are filled with the adhesive used to attach the carbon to the fiber structure); the adhesive used may outgas toxic gasses; in highly polluted conditions the carbon will become saturated quickly and breakthrough of harmful gasses will occur.