Air Purifiers and Ozone Generators: What You Need to Know

boy smelling odor

Ozone generators are one of the most common ways to quickly remove airborne contaminants and odors from homes, offices, and even cars.

While these machines can “shock” the air and deliver fast results, they can also be dangerous to our health, especially our lungs.

The same molecular process that makes ozone generators so effective is also what makes them dangerous. If you are considering the use of an ozone air purification to remove a strong odor or eliminate mold, you need to be fully informed on their history and proper use, as well as the alternatives to ozone generators.

But first, you need to understand what ozone is and why it’s so effective yet so harmful.

What is ozone?

We know you didn’t come here for a chemistry lecture, but if you want to understand ozone, you’re going to have to bear with us while we get into the details a little. Don’t worry, it’s really not that complicated, and there’s no test afterwards!

Ready? Here we go...

Ozone is made of oxygen molecules. The type of oxygen we are most familiar with, the kind we breathe every day, is actually dioxygen, or “02,” which is made of two oxygen molecules. (Technically speaking, we don’t actually breathe individual oxygen molecules, we breathe dioxygen.)

Ozone is simply three oxygen molecules, or “O3.” In the science world, ozone is referred to as “trioxygen”. This third oxygen molecule is unstable and only shares a loose connection with the other two molecules. Therefore, it will easily attach itself to pollution, especially high-odor pollutants like smoke. It can also attach itself to viruses, bacteria, mold spores, and organic matter. After it attaches to pollutants, the substance is destroyed. The ability to attach to other molecules, such as smoke and odor, gives ozone it’s ability to clean and deodorize indoor areas quickly.

What is an Ozone Air Purifier?

cigar smoke

One of the most common ways to “clean” air and remove strong odors is through the use of an ozone air generator, also known as ozone machines or ozone air purifiers. These machines are designed to create ozone through a simple process that occurs naturally in the atmosphere. However, like many things, just because it’s “natural,” doesn’t mean it’s healthy.

Because ozone is highly reactive, it is nearly impossible, at least with today’s technology and knowledge, to store it for any prolonged time. Therefore, it needs to be generated onsite through the use of high-tech machines.

Ozone air purifiers, essentially take in oxygen from the air (O2) and give it a strong electrical charge. This electrical charge allows the oxygen molecules to rearrange themselves and form O3, our famous ozone. (Did you know that because of electrical charges, ground-level ozone is often present in higher levels after a lighting storm?)

Now, the ozone is released from the machine into the air. When it hits molecules like mold or smoke, the third oxygen molecule attaches itself to molecules of the pollutant and basically eliminates it. The O3 attaches itself to bacteria, fungus, germs, odors, and other contaminants and, at the molecular level, destroys the cell wall. This process eliminates the contaminant while reverting the ozone back to oxygen.

Through this process, ozone generators can be extremely useful for cleaning pungent odors, removing the smell of smoke, and eliminating mold. They are used in hospitals, hotels, and even homes, but, as we’ll learn, they can be dangerous and must be used only by trained, qualified professionals.

Knocking the Lid Off Ozone Generators

Before 2005, “ionizing” air purifiers, which were essentially ozone generators, were used in homes to clean air and remove odors. For a while this seemed like a perfectly acceptable practice, but in the spring of 2005, Consumer Reports released a study that essentially condemned the use of ionizing air purifiers for every day residential purposes.

Their study found that five popular models not only did “a poor job of cleaning the air,” several of the units exposed users to “potentially harmful ozone levels.” This report brought to the public attention a serious issue with this type of air cleaning and caused the federal government to severely regulate and restrict the use of ioniser air cleaners (ionic air purifiers) and ozone generators. Ionizers in an air cleaner most often work by releasing negative ions. A by-product of the negative ion generators is ozone although the ozone output tends to be at a much lower level than an ozone air cleaner.

Consumer Reports is operated by the Consumers Union, a non-profit organization dedicated to influencing policy and providing unbiased information for consumers. This organization recommended that the federal government set indoor ozone standards for air cleaners and require the use of pre-market testing, as well as labels displaying test results.

This report prompted the government to play a larger role in the oversight and regulations of ozone generators (and air purifiers in general), and is often cited as an important part of the development and use of ozone products.

Ozone: Part of the EPA’s Monitoring

The Environmental Protection Agency takes comprehensive measures to monitor outdoor air pollution. While there are hundreds of potential contaminants in the air, they have emphasized six specific pollutants that present the largest danger. These pollutants include carbon monoxide, nitrogen dioxide, and (you guessed it) ozone. (In this case, they are referring to ground-level ozone, as ozone in the upper atmosphere is good because it helps block harmful UV rays.)

The EPA constantly monitors the quality of air all throughout the country. By using advanced sensory machines, they review the amount of certain pollutants and relay this information to news sources and the public. The hope is that when pollution levels are high, people can avoid the outdoors or take safety measures to protect their health.

But we’re talking about indoor cleaning. Why does it matter that EPA monitors outdoor ozone?

Think of it this way: ozone generators produce a chemical that is officially designated as a “pollutant” by the EPA. Ozone is dangerous enough for the EPA to monitor it, yet ozone generators literally release this substance into your home. That, by itself, should be enough to warn you of the dangers of ozone air purification.

Why is Ozone Unsafe?

smog and ozone

So why is ozone so unsafe in the first place?

Why is a chemical that is found naturally in the atmosphere and produced even more during lighting storms a concern for our health and well being?

It occurs naturally, so it can’t be that big of a problem right?

Well, radon occurs naturally, as does UV light, and for that matter so do floods, blizzards, and hurricanes. And as we all know, these can all be dangerous too!

Ozone is a highly reactive chemical. Because of its ability to react with the molecules in the air, it has an uncanny ability to remove strong odors and pollutants. But ozone doesn’t magically lose its reactive abilities when inhaled. On the contrary, when ozone is inhaled by humans, it remains just as reactive. This reactive nature is what makes ozone dangerous to humans and other forms of life.

When inhaled, ozone can create a reaction in the lungs. Even at low levels, this can create a wide range of health problems, particularly with the lungs. They can inflame and damage airways and make the lungs more susceptible to infection.

First, ozone can be a contributor to chest pain and coughing. It can cause shortness of breath, and irritation to the windpipes. These problems can inflict anyone who breathes in ozone contaminants, but they are especially potent for people with respiratory conditions such as asthma and allergies. Ozone makes it more difficult to breathe deeply, causing someone to struggle with getting enough pure oxygen for normal activity and daily function.

Ozone can also cause issues with the throat. This can come in the form of mild to serious coughing and, depending on the exposure levels and overall health of the patient, can disrupt normal daily functions.

One of the unfortunate natures of ozone exposure is that exercise can become bad for you. Under normal conditions, when you exercise you take in lots of healthy oxygen for your body, helping you continue your workout, get in shape, and live a healthy lifestyle.

However, when ozone concentration levels are high, physical exertion means more ozone in your lungs. In this case, working out can increase your overall exposure to ozone.

This is somewhat ironic; after all, you’re exercising to increase health, yet ozone can, in some form, make exercise bad for you. (Or at the very least, not as good for you.) Therefore, people who are more active often experience the worst effects from ozone.

Ozone May Reduce Immune System as Well

As if directly causing long-term health issues wasn’t enough, there is now mounting evidence that ozone exposure may also reduce the strength of our immune systems, leaving us more vulnerable to disease and infection.

One of the hazards of ozone exposure is a decrease in the body’s ability to fight respiratory disease. There is strong evidence that indicates people with prolonged ozone exposure are less physically-equipped to deal with health conditions in the lungs caused by bacteria or viruses.

A 2007 study from the Duke University Medical Center showed that breathing ozone inhibited the early immune systems in lab mice. They exposed mice to approximate levels of ozone that would be considered unhealthy for humans. Essentially, researchers found that mice exposed to ozone were more susceptible to bacterial toxins.

Ozone and Allergies, Asthma

child breathing fresh air

While ozone can have harmful effects on many people, it appears that people with asthma and allergies can be particularly at risk.

People who suffer from asthma have problems with restricting airways, which are aggravated by outside contaminants. Asthma can cause swelling inside the airways, a restricting motion from muscles surrounding the airways, or by a buildup of mucus in the pipes. Ozone is a problem for people with asthma for two important reasons.

First, smaller levels of ozone will affect their lungs. Levels that may seem inconsequential to the rest of us can cause breathing problems for people with asthma.

Second, the harmful effects of ozone can be more severe for asthma sufferers, causing more coughing, breathing problems, discomfort, or even pain.

Allergy sufferers may also experience more problems because of ozone. When combined with pollen, pet dander, or other airborne allergens, ozone can increase symptoms like lung or throat irritation and make the allergies even worse.

Ozone by itself can be bad for our lungs and overall health, but when combined with hay fever or other allergic reactions, it can make people more ill. Allergy sufferers who live in large cities or high-pollen regions can be particularly vulnerable to the effects of ozone.

Common Uses for Ozone Generators

We know that ozone generators can be harmful to our health. So why do we still use them?

Because despite the risks, they have a strong ability for cleaning, sanitizing, and removing offensive odors. Unlike an air purifier, you can’t operate an ozone air cleaner on a continual basis, but that doesn’t mean they should never be used. It simply means they need to be used cautiously.

bad odor

A few uses for ozone generators include:

  • Killing Mold and Mildew: Using ozone air purification to “blast” or “shock” mold and mildew is a common commercial practice. Airborne mold spores can be harmful to health, especially the lungs and respiratory system. Mold and mildew can trigger asthma and allergies, so removing them is always a top priority. However, mold removal often requires the removal and demolition of building materials, including wood framing, sheet rock, carpet, and ceiling panels. With ozone generators, mold can be removed in a relatively quick and affordable fashion.
  • Removing Bacteria, Germs, and Viruses: Disease-causing substances like bacteria, germs, and viruses are often hiding in plain sight. Places like the kitchen sink, bathroom floor, TV remote, and even the salt and pepper shakers can all hold bacteria and germs, increasing the likelihood of sickness in your home. Ozone generators, however, have proven abilities to remove many disease-causing substances by attacking the contaminants at the molecular level.
  • Removing Odors: One of the most common uses for ozone generators is the removal of odors. In the same way that it attacks mold or bacteria cells, ozone gas will also attack the physical airborne cells that make odors. This can be useful for many different purposes, including hotel rooms that have lingering smells from tobacco smoke. Another potential use is by landlords who need to remove the smell of pets from their properties, or by average homeowners who simply want to remove a foul odor in their home. Using ozone gas is often a last-ditch effort to remove an odor. When other techniques, such as cleaning solutions and scented air fresheners fail, having ozone concentrations can be used to “shock” the room.
  • There are other uses, but these are the main reasons that people choose to release ozone chemicals into their homes, businesses, and property.


How to Use an Ozone Generator Properly

If you decide to use an ozone generator to remove mold, bacteria, or odor, how should it be done?

As we’ve already established, when you use ozone, you are releasing a dangerous pollutant into your home, so you need to make sure everything is done right.

In almost all cases, it is best to use a professional cleaning and odor-removal company that offers ozone generators as part of their business. These experienced professionals are properly trained, so they have the knowledge and skills to complete the ozone process in a safe, efficient manner.

First, if you are using ozone to remove an odor, start by removing the source of the odor and cleaning as thoroughly as possible. This should include the use of safe liquid cleaners, vacuuming carpets, wiping surfaces, and dusting.

All of these measures will help make the odor removal more effective, and quite frankly, you may discover that after a good hard cleaning, ozone treatment is no longer needed.

Renting an ozone generator is usually preferred, but you can purchase one for personal use however you never want to be in the room when it is operating.

If you own a hotel, multiple rental properties, or a business that has strong odors (such as a restaurant or pet-related service), then purchasing an ozone generator may be a smart choice. However, if you are a homeowner, it’s probably wise to just rent, as you won’t need it on a regular basis and definitely would want to use as little as possible.

Every ozone generator will be different, so if you are using it yourself, be sure to follow, in every detail, the instructions for that machine. Make sure the windows in the home are closed and start the ozone generator by following the instructions. You will then need to leave the area and allow the ozone to do its work. Many units run on a timer, so they will turn off after a preset period. Once the period is over, allow the ozone to dissipate completely before entering the home or room. This can take a couple hours, so be patient and give yourself plenty of time. This is like treating your home for pests with chemicals. Avoid contact.

Here’s a few tips to make the cleaning process more effective:
  • Use a fan on low or keep your A/C fan running to allow for better circulation of ozone.
  • Running the A/C can also help sanitize the ductwork of mold and mildew.
  • Instead of doing a 12-hour marathon of ozone removal, try doing a few short periods to gradually erode the smell or mold.
  • Make sure EVERYONE is removed from the home during treatment, including pets.


With these tips, you can more safely use an ozone generator in your home. However, there are safer, more reliable options that clean the air without the added risk to your health and wellbeing.

While ozone generators have their place, room air purifiers with true HEPA and activated carbon filters can often be used to reach the same goals.

How are Ozone Air Purifiers Different from Other Purifiers?

All of this begs a serious question. How are ozone generators different from other air purifiers?

The differences, in fact, are immense. In most cases, air purifiers generally do not release pollution into the air. While ozone generators release a gas that is considered a pollutant to clean and sanitize, air purifiers simply filter the air.

For example, an air purifier that uses a charcoal filter will suck in air and move it across the filtering surface. The filter then traps pollutants, allergens, and other substances before the air is moved back out to the room. This is a fundamental difference between air purifiers and ozone generators. One releases a cleaning chemical, while the other simply filters pollutants from the air.

Another important difference is this: with an ozone generator, the actual cleaning happens outside of the machine, when ozone touches another substance. With air purifiers, the cleaning happens inside the machine, when pollutants are trapped by the filter.

Safe Home Alternatives to Ozone Air Purifiers

Ozone generators are often used for the purpose of removing strong odors in a room or removing mold and mildew. As stated above, the problem is ozone gas can cause long-term health issues.

However, if you choose the right air purifier, you can accomplish these goals without the harmful effects of ozone gas.

The Oransi OV200 air purifier, EJ and Erik models use mechanical air filtration only – HEPA filters plus activated carbon filters. These air cleaners do not have air ionisers or ozone output and remove a wide range of indoor air pollution including ozone gas and airborne particles.

Best Ozone Alternatives - Oransi Air Purifiers


Air Purifier Model Description
EJ120 Air Purifier EJ120 Air Purifier
This quiet, efficient air purifier has a medical-grade HEPA filter that removes up to 99.99% of all airborne allergens and particulates to give you fresh air that is ozone free. This purifier is especially effective for removing the smell of smoke from a home and can be used in large single rooms for noticeable results.

Erik 650A Air Purifier Erik 650A Air Purifier
This advanced air filter goes above and beyond HEPA filtration standards. Using a patented design, it has the highest level of filtration available on the market and helps your home or business smell fresh and clean. It removes odors from many sources, including smoke and pets, and can even be used for mold remediation.

Max HEPA Air Purifier Max HEPA Air Purifier
Using an activated carbon filter, this HEPA filter air purifier removes many different contaminants, including mold spores and other airborne particles. The activated carbon filter can also be used for light odor removal and gas removal.

Finn HEPA UV Air Purifier Finn HEPA UV Air Purifier
This sleek, convenient purifier is perfect for bedrooms and offices. This HEPA air cleaner actively removes mold spores from the air by using HEPA UV-C technology. UV light, which is used by this filter, can kill germs and mold spores, creating cleaner, healthier air.


Clean Your Air with World-Class Purifiers

Ozone generators have their place, but if you want a long-term solution to home and office air quality, you need an air purifier from Oransi.

Browse out large selection of top rated air purifiers and you’ll find the right machine for your specific indoor air quality needs and realize healthy, fresh air.

Want to learn more about cleaning your air? Check out this guide on how to choose an air purifier.
Discover Which Air Purifier Is Right For You

Discover Which Air Purifier Is Right For You

In just 3 simple steps you'll find the right air purifier for your needs.
Let's Get Started