About Ozone

What is ozone?

Ozone, (O3), is an energized form of oxygen which contains three atoms of oxygen rather than the two atoms we normally breathe. Ozone is the second most powerful sterilizer in the world and can be used to destroy bacteria, viruses and odors. Interestingly ozone occurs quite readily in nature, most often as a result of lightning strikes that occur during thunderstorms. In fact the “fresh, clean, spring rain” smell that we notice after a storm most often results from the creation of ozone. However, we are probably most familiar with ozone from reading about the “ozone layer” that circles the planet above the earth’s atmosphere. Here ozone is created by the sun’s ultraviolet rays. This layer of ozone serves to protect us from the ultraviolet radiation.

How does ozone work?

The third oxygen atom of ozone makes it extremely reactive. This atom readily attaches itself to other molecules. When contaminants such as bacteria or viruses make contact with ozone, it creates a miniscule whole in the cell wall.  Once the cell wall is destroyed, the bacteria will be unable to survive.. This process is called oxidation. Ozone essentially reverts back to oxygen after it is used. This makes it a very environmentally friendly oxidant.

Isn’t ozone a pollutant?

Unlike stratospheric ozone, which forms naturally in the upper atmosphere and protects us from the sun’s harmful ultraviolet rays, ground-level (or tropospheric) ozone is created through the interactions of man-made (and natural) emissions of volatile organic compounds and nitrogen oxides in the presence of heat and sunlight. Cars and gasoline-burning engines are large sources of volatile organic compounds (VOCs). VOCs also come from consumer products such as paints, insecticides, and cleaners as well as industrial solvents and chemical manufacturing. Nitrogen oxides (NOx), the other chemical precursor of ozone, are produced whenever fossil fuels are burned and are primarily produced by motor vehicles and power plants.  The sun’s direct ultraviolet rays convert these emissions into ground-level ozone, which is unhealthy to breathe. 

How is ozone measured?

1)      Concentrations

  1. a.      Parts Per Million (ppm) – This is the most common method.  So if we were to have 1 ppm that would mean that for every million parts of gas, one of those would be ozone.  (Note: ppb = parts per billion)
  2. b.      Milligrams(mg/l) OR  Micrograms(ug/ml) of ozone per liter – indicates milligrams/micrograms of ozone in one liter of total volume (gas or liquid).

2)      Ozone  Production

  1. a.      Grams of ozone per hour (g/hr) – ozone output for a generator.  We can measure the concentration of ozone in g/m3, then when we calculate for flow rate with a measurement such as LPM (liters per minute), we can determine how many grams of ozone are produced in one hour of time.
  2. b.      Milligrams of ozone per hour (mg/hr) – same as grams but a smaller measurement.

What is a gamma?

A gamma is essentially another term for mg/l (milligram per liter).  It is a measurement of the concentration of the ozone.  Therefore, 1 gamma = 1 mg/l.

Is ozone safe?

Ozone is safe if used correctly. However, high concentrations of ozone in the air can cause health problems if proper safety measures are not taken.   OSHA, has stipulated that the safe allowable level of residual is 0.1 ppm (parts per million). Note that this permissible level is for continuous exposure throughout an entire 8 hour day.

If you start to cough when around ozone there is too much ozone in the air and measures should be taken to remove yourself from the location or properly ventilate while ensuring that the cause of ozone in the air is remedied.  Do keep in mind that it takes an extended period of time at very elevated levels to cause irritation to the lungs.

How is ozone produced?

There are basically two methods of producing ozone…ultraviolet and corona discharge. Corona discharge creates ozone by applying high voltage to a metallic grid sandwiched between two dielectrics. The high voltage passes through the dielectric to a grounded screen/plate and in the process, creates ozone from oxygen present in the chamber. Ultraviolet (UV) light creates ozone when a wavelength at 254 nm (nanometers) hits an oxygen atom. Both processes split oxygen molecules into single oxygen atoms (O). These atoms combine with another oxygen molecule (O2) to form ozone (O3).

How long does the ozone last?

The length of time that ozone exists in a given substance is directly related to the ability of that substance to help ozone maintain its chemical composition.  For example, ozone that is created in the air will immediately begin the process of reverting back to oxygen.  A basic rule of thumb is that the half life for ozone in the air is 30 about minutes.  This means that every 30 minutes, the amount of ozone will decrease by 1/2.  Higher temperatures cause it to break down even quicker.


70 degree Fahrenheit 

50 degree Fahrenheit 

Olive Oil