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Ozone, air purifiers and public health

How much ozone is permissible indoors without causing negative health effects? Learn why indoor ozone is unhealthy and how to avoid it.

With so much public concern (rightly) about the health effects of ozone and establishment of safe standards, it’s surprising that so many countries still allow the sale of air purifiers that generate high levels of ozone. In the current debate over permissible ambient ozone levels in outdoor air the central question is, “How much ozone can we breathe without suffering negative health effects?” For public policymakers, it’s a matter of trying to balance business growth with public safety. But for cleaning the air in a home or office, there is absolutely no excuse for an air purifier to produce any ozone at all. And yet so many do.

There are two categories of air purifiers that produce ozone: a) those that deliberately produce ozone as their primary air cleaning mechanism, and b) those that produce ozone as the inevitable byproduct of ionization. Public health groups are not impressed with either technology, and the American Lung Association specifically recommends avoiding air purifiers that add ions or ozone into the air. The U.S. Environmental Protection Agency (EPA)  is equally unimpressed, especially with air purifiers that purport to clean the air by generating ozone. “At concentrations that do not exceed public health standards, ozone has little potential to remove indoor air contaminants,” says the EPA. Even worse, the EPA has found that ozone-generator air purifiers can produce levels of ozone indoors five to 10 times higher than public health standards.

Ozone is a reactive gas composed of three oxygen atoms. High in the earth’s atmosphere ozone helps protect the planet from excessive ultraviolet radiation. But close the ground, inhaled ozone can irritate the lining of the respiratory system, causing coughing, chest tightness and shortness of breath. Long-term exposure can cause or worsen asthma and even lead to premature death. Ozone is the primary component of smog. Ozone can also react with other chemicals, including some fragrances that give pine or citrus scents at home, to produce dangerous volatile organic compounds such as formaldehyde.

It’s worth noting that all IQAir air purifiers are 100 percent ozone free. They are certified by the International Association of Air Cleaner Manufacturers as producing absolutely no ozone. 

Since 2008, the EPA ozone standard for outdoor air has been 75 parts per billion (PPB). The EPA proposal that has been delayed would have revised the standard to 60 to 70 PPB in an effort to offer greater protection to those who suffer from a variety of respiratory symptoms. CARB found levels as high as 300 PPB in homes with ozone-generator air purifiers. “These concentrations are equal to, or worse than, a first stage smog alert,” CARB concluded. Since 2010, California has required air purifiers sold in the state to be certified as producing less than 50 PPB of ozone.

Whle other air purifiers are adding ozone into the air, IQAir systems are not. In fact, IQAir room air purifiers remove ozone from the air. The IQAir HealthPro 250 room air purifier with its V5-Cell filter will remove about 95 percent of the ozone in the air, and the GC MultiGas system can remove up to nearly 100 percent of the ozone

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