Do Molekule products produce ozone?

The simple answer is no, Molekule products do not produce ozone. Molekule products use PECO technology, or photo electrochemical oxidation, which is designed to improve indoor air quality through the use of a novel photocatalyst. Photocatalysts are substances that speed up chemical reactions when activated by light. Some early photocatalysts from other companies produced ozone and other substances that could be considered pollutants, which is the complete opposite of the scientifically proven effect of Molekule products. Extensive research over the past 20 years developed a photocatalyst that does not produce ozone or other harmful byproducts. In fact, PECO removes ozone from indoor air.

Molekule products do not produce ozone

PECO uses a photocatalyst. Traditionally, many photocatalysts were activated by UV-C light, which can produce ozone. Molekule devices contain UV-A light, also known as “blacklight,” that is proven not to produce ozone.

In addition, independent laboratory testing has confirmed that not only does PECO not generate any ozone, it actually removes it from the air. When Molekule devices are running the natural transition of ozone out of the atmosphere is sped up to make the air cleaner. Of course, Molekule is also certified by the California Air Resources Board to be ozone safe, as is required by law to sell our devices in California. We have also made the ozone test report that we submitted to the California Air Resources Board available on our website.

Where ozone comes from

Ozone is an interesting and somewhat common molecule. It is called a triatomic molecule because it is made up of three oxygen atoms. The oxygen molecules we breathe are diatomic and only composed of two oxygen atoms. Diatomic oxygen is a fairly stable oxygen molecule and makes up about 21% of the air we breathe

The third atom can only be added when it is split from diatomic oxygen, which takes a lot of energy. Typically this only occurs when diatomic oxygen is hit with a powerful source of light or reacts with a strong chemical and becomes two separate atoms. 

Lone oxygen atoms are extremely reactive and quickly join with other molecules such as diatomic oxygen. The third atom is an unstable addition and eagerly reacts with anything nearby to get away from the other two, so ozone doesn’t last long in the air compared to diatomic oxygen. In fact, the half life of ozone in the air is only about 8 hours before it returns to diatomic oxygen.

The sun and ozone

The most common source of energy that can break an oxygen atom in two so it has a chance to become ozone is exposure to ultraviolet light in the UV-C band from the sun. Both oxygen and ozone absorb UV-C light. As a result, at the edge of our atmosphere there is the ozone layer, which is a mix of oxygen and ozone that absorbs most of the UV-C light from the sun. This is fortunate because exposure to UV-C light can cause health problems in living things.

You can see here in this NASA image that UV-C light is stopped at around 30 kilometers or about 20 miles above the surface of the Earth. Image source: NASA

Ozone high above us is a good thing since it absorbs harmful ultraviolet light and cannot affect anything down on the ground. Ozone on Earth’s surface can be harmful because instead of changing back into oxygen, ozone might donate its extra atom somewhere that does damage. Rubber, plastic, fabrics, paint, metal, or any living thing can be damaged by exposure to ozone.


Oxygen needs a source of energy to be converted into ozone, and at ground level that comes from air pollution. Though the energy contained in burnable fuels can power a car or heat a home, it is rare that 100% of the energy is extracted from the fuel. As a result the exhaust emissions from cars and power plants contain VOCs and nitrogen oxides that have more chemical energy than the usual components of the atmosphere and readily react with other substances. When oxygen, VOCs, nitrogen oxides, and the UV light that makes it to the surface combine, ozone can result. 

Most modern cars have catalytic converters in their tail pipes. Once heated by the engine, these catalysts can convert VOCs and nitrogen oxides in the exhaust into non-reactive and relatively non-toxic substances such as carbon dioxide, water vapor, and nitrogen gas. This helps to prevent the formation of ozone on the ground. Many other things that burn fuels can be equipped with a catalytic converter to reduce these pollutants, such as power plants, generators, or even wood stoves.

Ozone generators

A third and less common source of ozone are ozone generating devices. There are a wide array of purported uses for ozone generators, but they are primarily used for sterilization since ozone is toxic to all living things including infectious microbes. Ozone can be useful in sterilizing medical instruments or water.

However, inhalation of ozone is harmful. The EPA takes a very strong stance on ozone generators used as air purifiers, and makes it clear that no government agency has ever approved their use and that exposure to ozone can cause a litany of health problems. It is even illegal to sell ozone-generating devices for the purpose of air purification in California, so all air purifiers sold in that state must be certified by the California Air Resources Board to be ozone safe.

Molekule devices can also handle other forms of pollution, not just VOCs like in car exhaust but also smoke, dust, and even biological particles like mold spores and viruses. Stay tuned to this blog to learn more about Molekule and about air quality.

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