Mold growth is a common problem in many homes and buildings. It not only poses a threat to the structural integrity of the property but also to the health of its occupants. As a result, people are constantly searching for effective methods to eliminate mold and prevent its recurrence.

One such method that has gained attention is the use of ozone generators. But does an ozone generator really kill mold?

In this article, we will explore the effectiveness of ozone generators in mold remediation and discuss their limitations.

Understanding Ozone Generators

Ozone generators are devices that produce ozone gas, which is a highly reactive form of oxygen. These generators are marketed as air cleaners and are often promoted as a solution for eliminating mold, odors, and other indoor pollutants. The idea behind using ozone for mold remediation is that ozone can kill mold spores and eliminate the musty odor associated with mold growth.

The Effectiveness of Ozone in Killing Mold

According to some sources, ozone can indeed kill mold spores. When ozone comes into contact with mold spores in the air, it can break down their cellular structure, rendering them inactive. This can help reduce the concentration of mold spores in the indoor environment and potentially inhibit mold growth.

However, it is important to note that the effectiveness of ozone in killing mold is limited and I have found some studies have proven they are not only dangerous but that they are also ineffective at removing mold.

For example, a study titled, “Evaluation of Antifungal Effect of Gaseous Ozone in a Meat Processing Plant,” found that after the treatment gaseous ozone, it did not show any inhibitory activity against mold strains, as optimum growth during all the trials was observed.” (1)

In another study of using an ozone generator to remove mold, the researchers discovered that “over a six-hour period in an average size room the device did not generate sufficient ozone to suppress bacterial and fungal growth.” (2)

Potential Safety Issues and Health Warnings

It can be so harmful that the Environmental Protection Agency (EPA) has listed ozone as one of six of the most dangerous air pollutants under the Clean Air Act which sets the standards for outdoor air quality to protect public health.

The Mississippi State Department of Health has issued warnings to its citizens that ozone is not effective in controlling molds and fungi, even at high concentrations far above safe health levels.

Also, ozone may damage materials in the home. For these reasons, the Mississippi State Department of Health strongly recommends that you do not use an ozone air cleaner in any occupied residential space. (3)

There are no federal agencies that have approved the use of ozone generators in buildings for human use, and the California Air Resources Board (CARB) has very stringent regulations for air filters sold in the state to ensure that they do not produce harmful levels of ozone.

According to the California Air Resources Board, “not only are ozone generators ineffective at cleaning indoor air, but inhaling ozone poses serious health risks for humans and animals. This fact sheet discusses these health risks and provides effective, alternative solutions to address indoor air quality problems.”

“Manufacturers sometimes inappropriately refer to ozone as “activated oxygen,” “super oxygenated” or “energized oxygen,