Common Ozone Myths and Facts
With any unfamiliar science or technology, you will inevitably encounter myths and misinformation. The myths about ozone are plentiful, but they generally come from lack of knowledge, bad science, or competitors’ marketing. We’ve heard them all. “It’s dangerous. It’s expensive. It’s not as good as chemicals.” It's time we set the record straight. Below is a list of a few ozone myths we have heard, along with the ozone facts.
1. I’ve never heard of ozone for disinfection – it must be new
Ozone disinfection is not new. Ozone was first reported by Van Mauren in 1785 after he noticed a distinctive smell in the vicinity of a lightning strike. It was identified as a compound in 1840 by Christian Schonbein. It has been widely used since the 1900s in water sanitation, medical environments, and food storage in Europe and The United States. Ozone was first used in bottled water plants in the 1970s, and Ozone Solutions has been providing ozone technology for nearly 25 years!
2. Ozone is dangerous for people
This is the most common myth that people use when arguing against the use of ozone, and it’s true to an extent. Inhaling high levels of ozone can damage the lungs. More moderate amounts over an extended period can cause chest pain, coughing, shortness of breath, and throat irritation. However, the only way this occurs with an ozone generator is by using it incorrectly, being unaware that one is in use, or not monitoring it. With aqueous ozone, there is no concern of inhalation as the ozone is injected directly into the water. That aqueous safety assurance does not hold true for most chemicals. There is the concern of chemical residue in water or on food, or in the case of chlorine in drinking water, the risk of carcinogens.
Ozone has been approved by OSHA, FDA, USDA, EPA, and National Organic Program, and has been GRAS (Generally Recognized As Safe) approved for direct contact with food products. Ask Ozone Solutions for a Material Safety Data Sheet (MSDS) if desired.
3. Chlorine is the better disinfectant choice
When you think about disinfectants, chlorine has the name recognition. And when it comes to killing bacteria and viruses, chlorine does a pretty good job. However, ozone is actually 50 times more effective at disinfection when compared to chlorine. Furthermore, the effects of ozone’s destructive sanitary capabilities are visible 3,000 times faster when attacking bacteria, viruses, yeast, molds, cysts, mildew, and most other organic and inorganic contaminants - many of which chlorine has little or no affect. Ozone has also been proven to kill SARS, MERS, and COVID-19 (Coronavirus).
4. Ozone is more expensive than other chemical disinfectants
While it is true that the initial capital costs for an ozone system are greater than chlorine, the long-term costs are much lower with ozone. Once an ozone system is installed, the only cost outlay is for scheduled minor maintenance. Ozone is produced on site, eliminating the need to transport chemicals like harmful chlorine, PPE products, sponges and cloths. Additionally, there are no storage costs or logistical uncertainties with ozone. Studies have shown that most ozone systems will start having cost benefits over chemical systems after 12-24 months.
5. Ozone is bad for the environment
You may have heard ozone is “good up high but bad nearby”. Stratospheric ozone is “good” because it protects living things from ultraviolet radiation from the sun. Ground-level ozone, primarily found in smog, is “bad” because it can trigger health problems for people of all ages who have lung diseases such as asthma. However, ozone generated in a controlled environment doesn’t need to have those negative effects.
Let’s start by understanding that ozone is just charged oxygen. Ozone is produced on-site from air (oxygen) and electricity. The oxygen (O2) molecules split when charged, and the individual oxygen atoms (O) join with other oxygen molecules to form ozone (O3). Ozone is very unstable and therefore has a short life. The gas will generally decompose within 30-40 minutes, leaving only oxygen! This is significant when contrasted against chemicals that often leave residues in aqueous applications that can leach into drinking water and ecosystems.
6. It Is Impossible to predict concentration levels
The EPA notes that it is increasingly difficult to determine the actual concentration of ozone produced by an ozone generator because of various on-site factors. Again, there is some truth to this, but it’s not impossible to predict or measure. First, let’s assume proper site preparation and proper unit sizing. Then, the “right level” of ozone is when all the generated ozone is being consumed. However, this is sometimes difficult to attain because it becomes a balancing act.Initially, the machine's output may be set higher to get rid of problem odors quickly. After that, less ozone is required for the diminishing odor, thereby leaving some residual ozone in the air. If the machine output is not adjusted, then more residual ozone will remain. It is also important to use an ozone monitor to ensure safe levels before occupying a treated space.
7. Ozone generators don’t purify the air
First, let’s (ahem) clear the air. An ozone generator is not an air purifier. Air purifiers sold as ozone generators are at best ineffective, or at worst, risk producing dangerous amounts of ozone above safety limits. New ozone technology can capture and remove excess ozone gas to both eliminate any potential danger and speed up the disinfection process in some occupied areas. However, you should consult with an ozone expert before using an ozone generator for continuous disinfection of any occupied spaces.
For most airborne applications, the benefit of an ozone generator is greatest for ongoing industrial disinfection, remediation, or shock treatment – situations where spaces will be unoccupied while the ozone machine is in operation.
8. Disinfection of a space can take months
Depending on the size of the space, the scale of the remediation, and the output capacity of the ozone generator, disinfection of a room may require several hours and for very large spaces several days. In most environments, thorough disinfection can take place overnight or over a weekend, and contrary to another myth, there is no harmful smell that remains for 24 hours. During room disinfection, the reaction and sterilization is instantaneous when the gas comes into contact with air or surfaces. Ozone has a 20- to 30-minute half-life in the air, meaning it will break down quickly. Humans should not go back into ozone disinfected room for approximately 2-3 hours after the cycle has been completed, and then it is 100% safe to resume activities.
9. Ozone will oxidize my metal pipes
This claim conjures an image of ozonated water running through pipes and when you come in the next morning, they are rusted through. This is not the case. pH level has more effect on corrosion rates of metals than most industry accepted dissolved ozone levels. While a powerful oxidizer, ozone has minimal effect on corrosion rates. Iron pipes that carry ozone gas, while not recommended, will last for months, or years, before any significant corrosion is present. For ozonated water, iron pipes will oxidize faster than water without ozone, but the pipes can last for years before needing replacement.
10. Ozone does not have any residual
This one is also false, but clarification is needed. Ozone has an extremely short half-life. This short half-life makes it very reactive and excellent at killing pathogens. In very clean water, ozone can last for several hours. In most food processing applications, ozone half-life is anywhere from 10-20 minutes. For wastewater applications, the ozone residual is dependent on the organic loading, with high organic loading resulting in short ozone half-life.
There you have it. The not-so-complete list of ozone myths and facts. If you have an ozone question (or a myth you want debunked), please contact us. The facts will empower you!