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What Is Ozone, and Why Are Large Amounts Bad for Your Health?

What You Need to Know about Ozone Exposure

Maybe you’re a city dweller concerned about pollution levels, or perhaps you’re someone considering an ozone-generating indoor air cleaner. Whatever your ozone-related concerns, here’s everything you need to know about ozone, including its negative and potentially serious health effects.

What Is Ozone?

Ozone (O3) is a neutral molecule comprised of three oxygen atoms. While it might seem similar to the oxygen we breathe (O2), ozone is actually a toxic gas. It’s odorless but has a distinctive smell, even at very low concentrations. Some find it smells a bit like cleaning products, chlorine, or bleach.

The oxygen atoms in ozone are strained, making them highly reactive. Ozone can negatively affect living things, such as humans, pets, and plant tissue, but because of its reactive nature, it can even attack inanimate objects, such as plastic. (Concentrations would have to be high for this to happen, but it is possible.)

Ozone is naturally present in outdoor air, but it’s generally found in very low concentrations in that circumstance, ranging from five to thirty parts per billion.

What Produces Ozone?

A number of products and processes can result in ozone. This includes the following:

  • Ultraviolet (UV) radiation
  • Lightning
  • Photocopiers
  • Laser printers
  • Medical equipment
  • Automobiles
  • Electrical equipment that involves electric motors

In larger quantities in the atmosphere, ozone can be helpful, minimizing the harmful UV rays that reach ground level. When ozone is present in large quantities at the Earth’s surface level, that’s when problems occur.

Cities, such as New York, Los Angeles, Houston, or San Francisco, with a lot of industry and traffic can generate dangerously high amounts of ozone. These levels are trackable online.

Negative Health Effects of Ozone

Ozone-related health effects are based on several factors: the individual, the exposure time, and the exposure intensity.

Who Is Most at Risk?

Ozone affects different people in different ways. It’s particularly harmful for children, the elderly, asthmatics, people with lung disorders (emphysema, COPD, and others), and people with reduced intake of vitamin C or E.

Exposure Time and Level

Exposure time and exposure level both play into the negative health effects you’d feel from ozone exposure. Even prolonged exposure to low levels could result in no adverse health effects. Alternately, very short exposure to extreme levels could be dangerous. OSHA, the EPA, and several other agencies define acceptable levels as no more than fifty parts per billion over an eight-hour exposure time.

Above concentrations of roughly 100 parts per billion, ozone begins to damage mucous and respiratory tissues. This damage can result in several symptoms:

  • Difficulty breathing
  • Shortness of breath
  • Painful deep breathing
  • Heavy feeling in the chest
  • Fluid in the lungs
  • Headache
  • Nausea
  • Coughing
  • Sore, scratchy, or burning throat
  • Inflamed or damaged airways
  • Worsened lung diseases, including asthma attacks
  • Lung disorders, cancer, and emphysema (symptoms associated with long-term ozone exposure)

The EPA confirms these symptoms and the adverse health effects related to ozone exposure.

Positive Uses for Ozone

Again, ozone high in the atmosphere is beneficial. (Regarding ozone, the EPA likes to use the maxim “Good up high, bad nearby.”) Ozone, however, has other helpful applications and uses as well.

For instance, it’s a powerful disinfectant, and it’s used often in remediation scenarios. Whether you’re trying to eliminate mold after a flood, harmful volatile organic compounds (VOCs), or smoke odor after a fire, ozone is invaluable in highly contaminated environments. The important caveat here is that no one—not humans or pets—can be present inside the space while ozone is being used. The levels administered during remediation would be extremely harmful.

While there’s some debate and controversy around it, low doses of ozone treatment have even been used in the medical field to address a variety of conditions, such as diabetic angiopathia, diabetic foot, chronic hepatitis, and certain chronic intestinal disorders. (Read the full medical study here.)

Ozone and Indoor Air Quality Improvement

One way many people are familiar with ozone is through air quality improvement devices that produce ozone. Yes, these devices effectively clean the air, but they also pose all the health and safety risks associated with ozone exposure. Especially if you’re running these devices in occupied spaces, either residential or commercial, that can be extremely problematic. Here’s an overview of what the EPA has to say about ozone generators sold as air cleaners.

If you’re considering different indoor air quality improvement systems, be certain they don’t produce any harmful by-products, including ozone. If you want proof of this, ask to see the company’s UL-867 certification. This will confirm the product has been put through independent testing and been found to produce less than fifty parts per billion of ozone.

If you have any questions about indoor air quality, ozone, or different technologies to improve air in an occupied space, please feel free to reach out. We’d love to help!