Using ozone on mold can be an effective remediation method if high levels of the agent are used. Spores on surfaces and circulating in the air can be killed by treatments of ozone on mold, but the process might not destroy mold growing inside walls and in other inaccessible areas. Most portable generators sold as ozone blasters do not emit ozone levels high enough to destroy mold.
Ozone is a reactive gas made up of three oxygen atoms, with two of those atoms representing the air breathed by people. When the third atom detaches from the other two, it can create a toxic gas that pollutes the air. This air pollution may harm the lungs, and in high concentrations may cause coughing, chest pain, and shortness of breath.
Manufacturers of ozone-generating devices advertise ozone blasting as effective for killing mold inside buildings. A home or business is commonly vacated and sealed before high levels of ozone are released. The effect of ozone on mold might be hampered because ozone may not reach spores in areas where air does not circulate, such as inside walls or other building material, and on porous substances. After the area has been purified, the building is cleaned to remove any remaining toxins.
Ozone in the upper atmosphere acts as a filter to protect against harmful ultraviolent rays released by the sun. When ozone infiltrates the air humans breathe, it can damage health. Ozone is produced from harmful chemicals that interact with the sun, like those from automobile emissions and industrial plants.
Studies have shown that at healthy concentrations, using ozone on mold might not produce any benefits or remove other contaminants from the air, such as carbon monoxide. Some health experts believe the application of high levels of ozone on mold could increase the number of hazardous chemicals in the air. The level of ozone on mold would have to be five to 10 times higher than what portable ozone machines emit to kill the toxins, according to the U.S. Environmental Protection Agency.
Mold needs moisture and organic nutrients to grow and spread. Controlling moisture inside buildings is recommended to prevent mold from starting to develop. Adequate air circulation can eliminate damp places where mold can flourish.
If mold is found, health experts advise sealing the area with plastic sheeting before cleaning work begins. A solution of bleach and water can be used to remove mold that's visible on surfaces. All cleaning materials should be sealed in plastic bags before being discarded, to prevent the spores from escaping. Once the cleaned area is dry, a vacuum with a special filter that traps tiny particles can be effective to remove any residual mold.