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How Long Does It Take For Ozone To Dissipate?

Last updated December 15, 2022

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When it comes to indoor air quality, finding the right product is extremely important in making your home a safer environment. Ozone generators are one option on the market and over the years have been a topic of discussion to figure out whether or not these machines are safe to run in our living spaces. 

What is Ozone?
Ozone is an inorganic molecule made up of three atoms of oxygen. Two of the oxygen atoms form the basic oxygen molecule. However, ozone is formed from a chemical reaction between oxides of nitrogen (NOX) and Volatile Organic Compounds (VOCs). Also known as hydrocarbons, they form by exposure to heat and sunlight and can occur on the ground and high up in the earth’s atmosphere.

Don’t we live under an ozone layer? 

Most ozone resides in the stratosphere and is proven to be a safety shield as it protects the earth from harmful ultraviolet radiation. It forms around 10-40 miles above the earth’s surface creating an ozone layer, this is known as ‘Good ozone’. Ground-level ozone, also known as ‘tropospheric’ is not emitted directly into the air but is created by chemical reactions. In the presence of heat and sunlight, NOX and VOCs that form from vehicle exhaust and industrial facilities will cause dangerous levels of ozone which can cause major health problems.

What is an Ozone Generator?

Ozone generator machines trap CO2 in the air to then convert it into ozone via an electrical discharge. This method is commonly known as ‘silent corona discharge’ which splits the oxygen and creates single oxygen atoms which eventually attach themselves to other oxygen atoms to form ozone. Ozone Generators are commonly used to remove indoor pollutants and odor from our household areas and automobiles, but quite often they are controversial amongst professionals due to the dangers they pose. 

Most ozone generators are equipped with an ion generator or ionizer which disperses negatively charged ions into the air. These ions attach themselves to nearby particles, giving them a negative or positive charge so that particles fall from the air and attach themselves to household surfaces such as walls, tables, and furniture.

Generators are to be used with extreme caution. While some studies have argued that these units help sanitize viruses, bacteria, and mold, one common fact remains amongst professionals, ozone can cause serious damage to our health, especially for people with ongoing health conditions. 

  • Humans exposed to ozone can develop respiratory and other health conditions. The ozone molecule reacts with organic compounds which are its main characteristics when it comes to tackling odor and general pollution. However, the same rules apply to the organic matter in the body which causes chaos in the immune system. Lung irritation, asthma, coughs, shortness of breath, eye irritation, and chest pain are all symptoms that can arise when exposed to ozone.  
  • Public health will be put at risk for the amount of ozone required. Eliminating viruses, bacteria, and mold will put human beings at serious risk as it requires a very high output from ozone generators. 
  • Children are more at risk. Ozone can attack the immune system and cause a reluctance to fight off infections. While anyone is at risk from excessive amounts of ozone, children, elderly people, and pets are more vulnerable even to little amounts also due to their immune systems being either not fully developed or slightly weaker and more susceptible to infections.
  • Indoor plants can suffer from exposure to ozone. Excess amounts of ozone can cause plants to develop irregular spots, become darkly pigmented in particular areas, and in the worst case, die. The molecule will eventually corrode the organic system after time and will show signs of reddening. Ozone concentration can also affect many household materials such as carpets, bedding, cushions, art prints, and electrical products.

How Long Does It Take For Ozone To Dissipate?

Ozone will be in the air from 30 minutes up to 4 hours before it will disperse back into oxygen. The higher the concentration levels of ozone the longer it will last in our indoor environment. While lower levels could take 1-2 hours to dissipate, it is recommended that you not return to a room for at least 4 hours after an ozone generator has been functioning to avoid any damage to your health. 

Ozone has a particular smell and may still be present hours after your generator has been disconnected. If the smell still remains, there may not be any harmful odor in the air but it is advised to give your room some breathing space for a day before returning to it. Some ozone machines are equipped with a timer which for safety is a strong recommendation; a preset shutdown will turn itself off when the job is done and avoids any risk of exposure while these units are in operation.

Final Thoughts

Ozone generators are sold as air cleaners and produce the harmful gas ozone. Some manufacturers make statements that these units can sanitize and purify the air, as well as remove just about every indoor air contaminant. This is not true. While there are some options for debate about ionizers and how they can remove certain indoor air contaminants, they have proven to be less effective than other particle and air cleaners such as air purifiers. Ozone is harmful to human beings. Short-term exposure can lead to coughs, eye and nose irritation, shortness of breath, and headaches. Long-term exposure can lead to harmful health consequences, particularly if you already suffer from ongoing health conditions such as asthma, or heart and liver problems.

Conclusion