California's Ban on Ozone Air Purifiers

In 2001, The Office of Environmental Health Hazard Assessment had released a report detailing toxic air contaminants, particularly in how they affect children; the resulting the Children's Environmental Health Protection Act enforced an ozone standard. Since that time, additional products have hit the market as studies into air quality have continued to progress with newer understanding of how purifiers affect both health and the environment.

In light of newer findings, not all air-cleaning devices are appropriate for home use. The California EPA Air Resources Board recommends that ozone generators, (air cleaners that intentionally produce ozone), not be used in the home as they're harmful to health.

What is Ozone?

Ozone is a gas molecule composed of three oxygen atoms. It has the capacity to cause serious health problems, including respiratory tract irritation and breathing difficulty.  It is a highly reactive, unstable, toxic gas. Ground level ozone is a major component of photochemical smog found in larger urban environments during the summer.

However, ground level ozone is different from the layer of ozone high up in the atmosphere, called stratospheric ozone.  This type of ozone offers protection by reducing the amount of ultraviolet light entering the earth's atmosphere. This helpful ozone layer is not be confused with the harmful ozone that occurs at ground level.

An important ingredient of smog, produced by hydrocarbon and nitrogen oxide gases, ozone is a highly reactive and unstable gas that has the potential to damage respiratory tract linings. This pollutant forms in the atmosphere through complex reactions between chemicals directly emitted from sources such as vehicles and industrial plants/factories.

Experts say that exposure to levels of ozone beyond minimal to standard air quality can lead to lung inflammation,  tissue damage, and impaired lung function. Ozone exposure is also associated with symptoms such as coughing, chest tightness, shortness of breath, and the worsening of asthma symptoms. Those at the greatest risk for exposure to this poor air quality include outdoor workers, athletes, children and others who spend greater amounts of time outdoors during smoggy periods. Elevated ozone levels can reduce crop and timber yields, as well as damage native plants. Ozone can also damage materials such as rubber, fabrics and plastics.

What are Ozone-Generating Air Cleaners?

Some indoor "air purifiers" or air cleaners emit ozone, a major component of outdoor smog, either intentionally or as a by-product of their design. Those that intentionally emit ozone are often called "ozone generators".   However, note that manufacturers sometime inappropriately refer to ozone as "activated oxygen," "super oxygenated" or "energized oxygen".  These types of references are misleading because they lead consumers to believe there is a charged ability in the product, when in fact there isn't.

This type of reference also implies that ozone is a healthy kind of oxygen. Since ozone reacts with some other molecules, manufacturers claim that the ozone produced by these devices can purify the air and remove airborne particles such as chemicals, mold, viruses, bacteria, and odors. However, ozone is not effective at cleaning the air except at extremely high, unsafe ozone levels, and even then it is only partially effective. Ionizers and electrostatic precipitators are other types of air cleaners that emit ozone, but they do so as a by-product of their design and function. These devices are designed to electrically charge particles and remove them from the air.  Even though devices typically emit less ozone than ozone generators, they still release ozone into the air through the charging process.

The California Air Resources Board, the California Department of Health Services, and other government agencies advise the public not to use so-called "air purifiers" that are specifically designed to generate ozone indoors (see references below). These ozone generators are sometimes marketed as emitting "trivalent" oxygen, "activated" oxygen, "allotropic" oxygen, "saturated" oxygen, "super oxygen," or "mountain-fresh air." These devices may also be combined with an ionizer or other technologies. However, these devices are actually emitting ozone, which (as stated before) can be harmful, especially for children, the elderly, and people with asthma, emphysema, bronchitis, or other respiratory diseases. Ozone irritates the eyes, nose, and throat, and may trigger asthma attacks.

Additionally, long-term exposure to ozone may permanently reduce a person's breathing ability. Research studies show that use of an ozone generator can produce harmful levels of ozone in a home - over three times the State outdoor air quality standard of 90 parts per billion. Ozone at safe levels does not clean the air. Independent studies by the U.S. Environmental Protection Agency, the Consumers Union, and others have shown that these devices do not effectively destroy microbes, remove odor sources, or reduce indoor pollutants enough to provide any health benefits. Ozone masks the odor of other indoor pollutants by deadening the sense of smell. It also reacts with certain indoor pollutants to produce toxic byproducts, such as formaldehyde. Ozone is used effectively in water to destroy microbes, but ozone in air must reach extremely hazardous levels (50-100 times the outdoor air quality standards) to effectively kill microbes.

What are the adverse health effects from exposure to ozone??

Ozone can harm the cells in the lungs and respiratory airways. Exposure to ozone irritates and inflames the lining of the respiratory system. It causes symptoms including coughing, chest tightness, and shortness of breath. In people with asthma, ozone can worsen asthma symptoms, and one study indicates that ozone may contribute to the development of asthma. Ozone impairs breathing. Elevated exposures to ozone can cause permanent lung damage, and repeated exposure can even increase the risk of dying among people already in poor health. People particularly vulnerable include children and those who suffer from asthma or other respiratory diseases, including the elderly. Due to the health hazards of ozone, California has worked aggressively for decades to reduce outdoor ozone levels, with considerable success. In addition to its impacts on health, ozone can also damage materials such as rubber, fabrics, plastics and other indoor furnishings.

Adopting a regulation to limit the ozone emissions from indoor air cleaning devices, the ABA has formed a list of potentially hazardous ozone generators sold as "air purifiers"

Safe to Use

It is possible to find portable air purifiers that don't emit ground ozone. These air cleaners are different from air ionizers; rather than neutralizing the electric charge, portable air purifiers actually filter through the air.  Portable air cleaner 's are practical for existing homes where the addition of a central air cleaner is too costly.  Proper size, installation and maintenance are critical for portable air cleaners to be effective.

To determine which air filter best suits your needs, check the room size rating (in sq feet) before purchase and choose the unit appropriately sized for your situation, which in most cases calls for a home air purifier.  However, if your needs are more compact, then consider a room air purifier.

Some safe and approved cleaners include the BlueAir Air Filter, the AustinAir Air Cleaner, and the IQ Air Purifier. Whichever you decide to get, note that placement is the second most important consideration.

Place the unit in your room where you spend most of your time or have the worst symptoms. Locate the unit away from doors, windows, and foot traffic, but not close to walls or corners, so as to not block the air from reaching the air cleaner.

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