Ozone generators are popular air-cleaning devices that have become more widely used since the COVID-19 pandemic created awareness of the need for cleaner air in occupied spaces. However, ozone has been known to have detrimental health effects on humans when exposed to specific concentrations for extended periods. Therefore, when considering ozone generators for air cleaning, realize they must be operated with great care as ozone generating electronic air cleaners can emit unsafe ozone levels.
Ozone generators are devices that produce ozone (O3), which cleans contaminants from the air. Ozone is a colorless, toxic gas with powerful oxidizing properties. There are both good and bad forms of ozone:
Stratospheric ozone, or “good ozone,” is found in the atmosphere between 6 and 30 miles above the Earth’s surface. The ozone layer shields us from harmful UV radiation from the sun. Ozone at the ground level, or “bad ozone,” is an air pollutant harmful to our health. Ozone generators typically produce “bad ozone.”
Unfortunately, no. The EPA has denounced these devices and cites several scientific studies showing they can be harmful to health and ineffective at removing airborne contaminants. That is why no federal agencies have approved ozone generators for use in occupied spaces.
Ozone is composed of three atoms of oxygen, hence O3. Two atoms from the oxygen we breathe; the third can detach from the ozone molecule, reattach to molecules of other substances, and change their chemical composition.
Ozone generators harness that chemical reaction by filtering oxygen (O2), then using an electrical charge to break apart oxygen molecules, encouraging them to reform as oxygen and ozone.
There are two methods used to generate ozone:
Just as ozone reacts with organic material in the air, it can react with organic material in our bodies, leading to health problems. When inhaled, ozone directly affects our lungs and respiratory system. It can cause airway hyper-responsiveness, including shortness of breath, wheezing, and coughing. In addition, if you have a lung condition, like chronic obstructive pulmonary disease (COPD) or asthma, ozone can exacerbate it. Potential health risks from ozone include:
Long-term ozone exposure happens when you inhale ozone for more than eight hours a day over weeks and months. This type of exposure has been linked to the risk of hospitalization for asthma and numerous respiratory-related conditions.
When it comes to ozone-generating devices, there are rules and guidelines for how much ozone can be emitted by a product and how long workers can be exposed to certain amounts. Here are some recommendations for human exposure to these devices (see the Clean Air Act):
Risk factors are largely determined by the ozone concentration, the duration of exposure, the activities during exposure, and pre-existing conditions (like asthma).
Ozone generators are often lumped in with ionizers. However, while ionizers are also air-cleaning devices, they work by electrically exciting ions in the air, encouraging them to latch onto air particles, which eventually get collected by the device.
Ionizers are known to remove pathogens and viruses, but they are not effective at eliminating odors and volatile organic compounds (VOCs). Since many odors are VOCs, including smoke, pet smells, and mold, ionizers will not work if you need to remove odors or these types of particles.
There is great debate about air cleaners such as ozone generators and ionizers, the health effects of these devices, and whether the indirect or direct ozone output can be harmful. The EPA took this to heart, especially since there is much material— primarily produced by manufacturers—that claims ozone is not necessarily harmful to your health.
After conducting a study, the EPA came to several conclusions about ozone generators, including:
Ozone generators are not a safe choice for cleaning the air in occupied spaces. However, the device can be helpful when used in uninhabited areas for a long time, such as cleaning up natural waste. The room should be as closed off as possible for the generator to work and ventilated before the space is reoccupied.
Since ozone can be harmful to human health, companies need to be careful how the devices are used. In addition, ozone generators can take months to work. Therefore, if you are looking to improve the indoor air quality of your business by running it overnight, it will be a waste of time and money.
When it comes to your inhabited workplace, ozone generators do not fall under best practices for indoor air quality. Even if manufacturers say the device does not produce ozone in hazardous amounts, do your research and try to identify how much ozone the device emits. You will also need to pay attention to the square footage the device was tested in compared to the size of your space. If a very large room is required to run the ozone generator effectively, smaller businesses may not be feasible.
Instead, opt for a multi-stage air cleaner that does not produce ozone, or if it does, it is generated indirectly and in small amounts. It would be more advantageous—and safer—to get an air purifier that can operate while people are in your building. You can also take advantage of additional filters (like HEPA filters), UV-C light technology for killing viruses, and activated carbon filters for removing VOCs. Contact us to get started with a customized plan to clean your air effectively and safely.