California Air Resources Board

Unfortunately, some electronic air cleaners and other consumer products generate ozone, which could harm your health. Ozone is a reactive gas comprised of three oxygen atoms. While ozone high up in the atmosphere protects us from the sun’s harmful UV rays, ozone at ground level can cause health problems such as coughing, chest tightness and shortness of breath. Exposure to ozone may both induce and worsen asthma symptoms and worsen lung disease; and chronic exposure may also increase the risk of premature death. Some consumer products and home appliances are designed to emit ozone, either intentionally or as a by-product of their function. Such devices can produce levels of ozone several times higher than health-based standards set for ozone.