Ozone for Disinfecting Air and Surfaces
Ozone disinfection systems supplement UV-C disinfection, because ozone, being a volatile gas, can disinfect areas that are not possible to disinfect using UV-C systems, e.g., because it is not possible to radiate the area to be disinfected (shadows).
The starting point for this development was the use of ozone-generating UV-C lamps with a wavelength under 200 nm in industrial exhaust air systems to eliminate organic odors and grease. As a volatile, unstable gas, ozone – also called reactive oxygen – is distinguished by high reactivity with predominantly organic substances contained in the air. As part of this oxidation process, called photocatalytic oxidation, the ozone is completely used up and breaks down into oxygen again. Within the field of science, many institutions have been dealing with the subject of eliminating germs using ozone or ozone’s impact on microorganisms.
The process of photocatalytic oxidation is a method of air purification that has been “borrowed” from the surrounding world. For example, on extremely hot and humid days, the air is stifling and filled with damaging substances from traffic and industry. During thunderstorms or when lighting strikes, ozone is formed in low concentrations so that the air is then perceived as clear and clean again. This is similar to air purity at various altitudes. Therefore, even today, it is recommended that asthmatics spend their holidays in the mountains, because there is a higher concentration of ozone (though still very small) at higher altitudes, which makes the air there purer and clearer when compared to typical “lowlands.” Radio announcements about high ozone concentrations on hot summer days are nothing more than news about air pollution, so the expression “ozone” has become colloquially linked to an incorrect image. When used in exhaust air purification or disinfection, ozone has been proven to be an effective, ecological alternative to chemical processes.
Eliminating pathogens with ozone is a technology that produces ozone in conjunction with atmospheric oxygen via controlled UV light – an environmentally friendly method inspired by nature, which produces no dangerous by-products, such as nitrogen oxides. When ozone comes into contact with microorganisms and of course with odor molecules, it breaks down and oxygen is produced as a by-product. The fresh scent after using ozone disinfection is reminiscent of the scent of air after a storm and emphasizes how natural this method of air purification is. It is also worth mentioning in this context that ozone is made exclusively using a specific wavelength of light, and we thus avoid creating nitrogen oxides, which occur when ozone is manufactured using high voltage.
Other scientific studies on the subject of ozone disinfection can be found here:
- Surface Germicidal Effects of Ozone for Microorganisms
- Bactericidal Effects of High Airborne Ozone Concentrations on Escherichia coli and Staphylococcus aureus
- Demonstration of a Hermetic Airborne Ozone Disinfection System: Studies on E. coli
- Ozone Contribution in Food Industry in Japan
- Ozone for Inactivation of Aerosolized Bacteriophages
- Inactivation of Vegetative and Sporulated Bacteria by Dry Gaseous Ozone