Ozone Facts
Oxidation Strength Comparison
When dissolved in water (pH 7.4-7.6), ozone is at equilibrium: creating half ozone molecules and half hydroxyl radicals.
Ozone Facts and Fallacies
Fallacy | Fact |
---|---|
Ozone is dangerous, corrosive and off-gasses | Ozone has been safely used in thousands of applications with no off-gas and no danger to humans or the environment with accepted management practices. |
Ozone is cost-prohibitive or expensive | Ozone is very affordable and offers so many benefits. It is a natural, environmentally sound sanitizer to which no microorganisms can build an immunity, and adds no byproducts to the water |
Ozone is an oxidizer only | Ozone is a highly efficacious sanitizer, disinfectant and purifier; these provided by its strong oxidation capabilities |
Ozone is not as strong as traditional sanitizing chemicals | Ozone is exponentially stronger and more efficacious than all standard sanitizers (10-15,000 times greater) and very safe |
Ozone is new technology | Ozone is an approved sanitizer that has been used in numerous applications since 1906 |

Ozone is an Approved Sanitizer
- Food contact surfaces, non-food contact surfaces & CIP/SIP
- Direct Food Contact and Bottled Water
- Pharmaceutical processes (CIP/SIP/surfaces/product water)
- Personal Care Product and Industrial sanitation processes
- Irrigation water, potable water and waste water
Ozone Properties
- Ozone is a gas produced at the point of use in a device called an ozone generator utilizing air or oxygen-enriched feed gas and electricity
- Oxygen molecules (O2) split with the addition of energy, resulting in two individual oxygen atoms (O1)
- Oxygen atoms (O1) unite with other oxygen molecules (O2) to produce Ozone (O3)
- (O1) + (O2) = (O3) as represented in the diagram


Ozone Oxidizing/Sanitizing Properties (Gaseous or Aqueous)
- The third oxygen atom is held by a weak single bond
- An oxidation reaction occurs upon any collision between an ozone molecule and a molecule of an oxidizable substance
- The weak bond splits off leaving oxygen as a by-product
- The third atom oxidizes the cell membrane, ultimately causing cell bursting (Lysing) and destruction
- This process can attain complete sanitation on surfaces (i.e. 6 log reduction – 99.9999%)
Electron Micrographs of E. coli
Before/After Ozone Treatment

Ozone Functionality
- Ozone is a strong oxidizer, disinfectant and sanitizer
- Ozone has a short half-life (seconds to minutes depending on temperature and pH if aqueous; minutes to hours in air), and reverts to oxygen
- Ozone is generated and applied on-site
- Ozone can be utilized as a gas or a fog (in a confined and controlled-access space) or it can be dissolved in water for targeted application


Ozone Benefits
- Ozone is an efficacious antimicrobial oxidizing agent, disinfectant, and sanitizer
- The disinfecting capability of 1 PPM Aqueous Ozone is equivalent to many times (10 to 4,000 times) the concentration of free available chlorine (Morris, 1975 – Disinfection: Water & Wastewater), depending on pH, temperature, and on the specific microorganism(s) to be destroyed
- Some microorganisms (oocysts such as Cryptosporidium parvum) are tolerant to chlorine but are destroyed by ozone
- Bacteria (and viruses) cannot develop a tolerance to ozone because disinfection occurs by the high oxidation power of ozone attacking cell walls/membranes (bacteria) or the DNA chains (viruses)
- Aqueous ozone is documented to effectively break down and remove biofilms of varying types
- Ozone (sometimes alone, sometimes combined with UV radiation or hydrogen peroxide) is documented to destroy pharmaceutical pollutants such as endocrine disruptors
Ozone is a Sustainable Technology
- Ozone is produced with ambient air and electricity in an apparatus (ozone generator) which utilizes very low energy
- There are no consumables utilized in an ozone generator
- Ozone is not stored, transported or discarded
- Its primary byproduct is natural oxygen, the same oxygen we breath to sustain life
- Microorganisms cannot build up a tolerance to ozone
- Ozone is an approved food and organic food additive
- Its use cannot harm the environment or eco system
- It is more efficacious than traditional sanitizing chemicals; reducing their use and disposal
- Ozone is used in cold water; resulting in energy savings


Ozone Innovative Applications
- Ozone can be applied as an aqueous product
- It can be hard-plumbed into existing sanitation lines as a centralized system
- It can be utilized with hand-held or fixed sprayers
- It can also be used as a flood or cascade
- Aqueous ozone is sprayed at low pressure (20 psi or less) in cold water (<70°F)
- Low-pressure use is designed to gently flood surfaces without causing pressurized over-spray that can inadvertently spread microorganisms to other areas of a facility.
- Gaseous ozone and ozone fog can be applied in controlled environments for microorganism control and spoilage reduction which results in increased shelf-life and increased yield.
- Gaseous ozone and ozone fog can be applied in controlled environments for microorganism control and spoilage reduction which results in increased shelf-life and increased yield.
Ozone Proven Technologies
- Ozone use will reduce levels of fat, oil & grease on surfaces, and it will break down microorganism and biofilm build-up on all surfaces
- Its continuous use will sanitize floor drains with no adverse effect on wastewater treatment systems
- Ozone helps to rid drains and plumbing of biofilm and other microorganisms that can migrate back into the processing area (esp. Listeria monocytogenes)
- Ozone is beneficial to sewage treatment systems because it adds dissolved oxygen to the wastewater to be treated
- Ozone sanitation sprays keep conveyor belts clean and free of build-up. “Build-up” may consist of food debris, sugar, fat, grease, etc., while harboring biofilm that may consist of any number of human pathogens, as well as fungi

Chlorine vs. Ozone – 11 Days Without Sanitation – Fruit Production Facility

Ozone Sanitizing in Industrial Applications
Other facilities utilizing ozone for various sanitation processes include:
- Pharmaceutical processing facilities
- High purity water for biotech processors
- High purity water for semiconductor producers
- Cosmetic and Personal Care product processors
- Process Water Recycling
- Municipal drinking water and wastewater treatment
- Anywhere wettable surfaces need to be sanitized.
Ozone Safety & Control
Ozone (Gaseous) Safety & Control
- OSHA PEL: 0.1 PPM 8 hour
- OSHA STEL: 0.3 PPM 15 min
Ozone (Aqueous) Safety & Control
- PEL: none established
- STEL: none established
- Eye Contact:: may cause mild irritation; not expected
- Ingestion Hazard: not ingested during application
- Inhalation Hazard: not likely; exposure to aerosolized aqueous ozone could become irritating
- Skin Contact: not hazardous
Aqueous ozone systems operated according to GMP, are safe for workers; these systems utilize monitor/control devices to continuously adjust operational parameters to ensure proper efficacy and safety.
If catastrophic leaks happen, air monitor set point is exceeded; monitors instantly cut off electricity flow to ozone generators stopping production of ozone.
Ozone Material Compatibility
Components & Piping
Material | Ozone gas < 2500 ppm | Ozone gas > 2500 ppm |
Glass | ||
Ceramics | ||
PVC | NR | |
CPVC | NR | |
UPVC (unplasticized) | NR | |
Aluminum | (4% wt max) | |
304 L stainless steel | ||
316 L stainless steel | ||
UPVC (unplasticized) | ||
Superalloys Such as Inconel1 and Hastelloy-C2 | ||
Titanium | ||
Perfluoroalkoxy Resin (PFA) such as Teflon®3 or equivalent | ||
Fluorinated ethylene propylene (FEP) such as Teflon®3 or equivalent | ||
Polytetrafluoroethylene (PTFE) such as Teflon®3 or equivalent | ||
Ethylene tetrafluoroethylene (ETFE) such as Tefzel®3 or equivalent | ||
Ethylene chlorotrifluoroethylene (ECTFE) such as Halar®4 or equivalent | ||
Neoprene® or equivalent | NR | |
Polyvinylidene fluoride (PVDF) such as Kynar®5 or equivalent | ||
P-chlorotrifluoroethylene P-CTFE such as Kel-F®6 2800 and Neoflon®7 or equivalent | ||
NOTE 1 — Abbreviations for components, piping, gasket and seals are in accordance with ASTM D4000. 1 Special Metals Corporation, 2 Haynes International, Inc., 3 Dupont, 4 Ausimont USA, Inc, 5 Elf Atochem North America, 6 3M Company, 7 Daikin Industries NOTE 2 — NR – not recommended |
Gaskets & Seals
Material | Ozone gas < 2500 ppm | Ozone gas > 2500 ppm |
p-chlorotrifluoroethylene (P-CTFE) such as Kel-F®1 or equivalent | ||
perfluorelastomer such as Kalrez®2 or equivalent | ||
perfluorinated copolymer such as Chem-Rez®3 or equivalent | ||
Gortex® or equivalent | ||
PTFE tape | ||
chlorosulfonated polyethylene such as Hypalon®2 or equivalent | NR | |
vinylidene fluoride such as Viton®2 or equivalent | (4% wt max) | |
polydimethyl siloxane (silicone) | (4% wt max) | |
ethylene propylene diene monomer (EPDM) | NR | |
1 3M Company 2 Dupont 3 Green, Tweed and Company NOTE — NR – not recommended |
Surfaces
Material | Ozone gas < 2500 ppm | Ozone gas > 2500 ppm |
Concrete, painted concrete | ||
Rubber Modified Vinyl | NR | |
Galvanized Steel | NR | |
NOTE — NR – not recommended |
How is Ozone Measured
- Dissolved ozone is measured by an Oxidation Reduction Potential (ORP) monitor/controller, as well as an electronic dissolved ozone monitor/controller
- The ORP reading can range between 600 mV to 900 mV at the point of introduction into the main return line before entering the pool
- An ORP of 800 mV is ~ 0.2 PPM dissolved ozone which is estimated to equate to ~40 PPM Cl in terms of oxidation and antimicrobial efficacy
- An increase of 100-200 mV ORP over the Cl ORP is a significant increase in oxidation of contaminants
Understanding ORP (REDOX)
- ORP (Redox) stands for Oxidation Reduction Potential
- ORP measures the water’s cleanliness, the ability to break down contaminants, and the antimicrobial potential of the water
- Oxidation is measured by the ORP probe sending the signal in millivolts (mV)
- Positive ORP indicates the presence of an oxidizing agent
- Negative ORP indicates the presence of a reducing agent (severe impurity)
- In general, tap water has an ORP of about 200 mV
- Chlorinated tap water can be up to 600 mV
- Water with an ORP of 650 mV or greater will not harbor harmful pathogens