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Ozone Does Not Kill Mold

Table of Contents

Does Ozone Kill Mold? Debunking the Myth

What Science Says

Contrary to popular belief, ozone does not effectively remove mold contamination. Mold is a living organism. When it is deprived of oxygen with ozone, it will “die” BUT the dead mold spores can produce mycotoxins which are the harmful part of “toxic mold”.  The assumption is that is mold is “dead” it can’t hurt humans and pets. False. Mycotoxins continue to be produced by “dead” mold spores. And, if the leaks and/or elevated humidity are not corrected completely, the mold growth will return.

Mold growth is primarily caused by water and cellulose. To truly tackle a mold problem, the source of water must be eliminated first. Then, all materials affected by mold spores should be either replaced or professionally cleaned. So, if you’re considering using ozone for mold cleanup, think again. The mold will continue to grow until the root cause—water—is addressed.

Ozone will temporarily reduce the airborne toxic mold spore count levels, but they will quickly return when water or elevated humidity occurs.

The air purifiers sold for home use do not emit enough ozone to kill very much air borne mold; adding ozone is a marketing trick used by the manufacturers. All home use air purifiers emitting ozone do is add to global warming.

Professional remediation companies (we do not perform mold remediation) will tent the area or the building before injecting ozone, similar to termite building tenting.

The EPA says this: “When used at concentrations that do not exceed public health standards, ozone applied to indoor air does not effectively remove viruses, bacteria, mold, or other biological pollutants.” 

Ozone's Role in COVID-19 Cleanup

The Uncertainties

Ozone is a popular choice among COVID-19 cleanup contractors, but does it really work? The answer is not straightforward. Surface testing is available but only covers a limited area. Moreover, if someone with COVID-19 enters the area, that will contaminate the area again.

Third-Party Testing vs Manufacturer Testing

Some manufacturers provide their own testing kits, but these may not be as reliable as neutral, third-party EPA-approved tests. The conflict of interest is clear, and the science behind such methods is not universally accepted.

The Challenges of COVID Testing

COVID swab sampling is the most widely used testing method for buildings. However, getting accurate results can take time, ranging from a few hours to several weeks. This delay hampers contact tracing efforts and makes the “clearance” unreliable.

Measuring the air-borne load of particles under the 2.5PM is sometimes used as an indicator. Note: most viruses are smaller than 2.5PM. Also, someone with a common cold that sneezed recently could impact the results.

So, there is no clear, reliable method to test for airborne Covid.

Ozone as a Greenhouse Gas

Environmental Impact

While ozone is effective in cleaning up smoke and other particles, it’s also a greenhouse gas that contributes to climate change. For mold remediation ozone doesn’t fix the underlying issues – leaks or high humidity – that led to the elevated mold growth in the first place.

Alternatives to Ozone

There are paints and sealers that can encapsulate odors. If you’re considering this option, make sure to opt for products with low or no VOCs (Volatile Organic Compounds). One manufacturer of these products is Safe Seal. We have no affiliation with them, but they make a good product.

Health Concerns Associated with Ozone

The EPA’s Stance

The EPA strongly advises against using home ozone generators. Ozone is a lung irritant and can be harmful at certain levels. The FDA has set a limit of 0.05 parts per million of ozone for medical devices.

The Risks

High levels of ozone can be dangerous and are generally considered unsafe for humans. Always be cautious and read the labels if you’re considering buying an “ozone generator.”

Ionizers and Other Ozone-Generating Air Cleaners

What Are They?

Ionizers and other ozone-generating air cleaners also produce ozone, albeit indirectly. These devices can produce ozone levels significantly above what is considered safe for human health.

Consider Alternatives

For the sake of everyone’s health, it’s better to consider different methods for mold cleanup. Feel free to contact us for free mold cleanup recommendations.