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Over 31 years professional experience
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Ozone system development, ozone applications development, and project management
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Food Safety, Wineries, Aquatics, Pharmaceutical and Industrial
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Experienced with regulatory compliance responsibilities for the use of ozone
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Developed parameters for ozone efficacy and worker/environmental safety protocol for surface sanitation; water and product sanitation with species-specific pathogens, with accredited third-party testing agencies
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Authored regulatory code for numerous ozone applications
Further Information
A Brief History – Ozone Experience
Ozone Milestones – Sanitation
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University studies regarding the efficacy of gaseous and aqueous ozone for sanitation applications (1997 to present)
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NSF International to develop J-00047649; testing and validating the efficacy of low-dose aqueous ozone for a 3 log (99.9%) reduction of Cryptosporidium parvum (2007)
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NSF Toxicology Group to test the efficacy and safety of aqueous ozone against US EPA DIS/TSS AOAC methodologies in conjunction with OSHA standards (2000)
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MAFMA (USDA) grant as an industry collaborator for the use of ozone in Clean-In-Place technology for Food Safety (2009)
Aqueous Ozone Used as a Sanitizer
Ozone Properties
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Food contact and non-food contact surfaces and CIP/SIP
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Direct Food Contact
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Pharmaceutical processes (CIP/SIP/surfaces/product water
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Industrial sanitation processes
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Ozone is a gas produced at the point of use in a device called an ozone generator utilizing oxygen-enriched feed gas and electricity
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Oxygen molecules (O2) split with the addition of energy, resulting in two individual oxygen atoms (O1)
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Oxygen atoms (O1) unite with other oxygen molecules (O2) to produce Ozone (O3)
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(O1) + (O2) = (O3) as represented in the diagram
Ozone Properties
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The weak bond holding ozone’s third oxygen atom causes the molecule to be unstable and consequently a strong oxidizer, disinfectant and sanitizer
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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
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Ozone is not a chemical that can be stored; it must be generated and applied on-site
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Ozone can be utilized as a gas (in a confined and controlled-access space) or it can be dissolved in water for targeted application
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When ozone is utilized for surface sanitation, direct food contact and CIP/SIP it is dissolved in water
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Gaseous Ozone dissolved in water is referred to as Aqueous Ozone (which does not off-gas when applied appropriately)
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When ozone comes into contact with a bacterium, the most active but most weakly bonded oxygen atom separates and oxidizes the cell membrane, ultimately causing cell bursting and destruction
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The weak bond splits, leaving oxygen as a by-product
Ozone Benefits
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Ozone is an efficacious antimicrobial oxidizing agent, disinfectant, and sanitizer
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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
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Some microorganisms (oocysts such as Cryptosporidium parvum) are tolerant to chlorine but are destroyed by ozone
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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)
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Aqueous ozone is documented to effectively break down and remove biofilms of varying types
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Ozone (sometimes alone, sometimes combined with UV radiation or hydrogen peroxide) is documented to destroy pharmaceutical pollutants such as endocrine disruptors
Ozone Byproducts & Safety
Common Applications of Aqueous Ozone
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The usual ozone by-products of organics (aldehydes, ketones, organic acids) are beneficial to the environment and (in the low levels formed during disinfection/sanitizing) are not toxic to people
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Ozone leaves no residual on surfaces because of its short half-life
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Ozone monitoring and system controls are always installed as part of an ozone generating and application unit
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Ozone is a sustainable product with an over one-hundred year history of safe and practical commercial uses
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Drinking water, bottled water, wastewater
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Marine aquaria, aquaculture, laundries, pharmaceutical, ultrapure waterpreparation (electronics), water reuse
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Pulp & paper bleaching, kaolin bleaching
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Agriculture irrigation water, ground water remediation
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Food processing and food service
Ozone Applications
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CIP/SIP, surface sanitation, biofilm removal, process/product water, direct food contact
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All of these commercial applications for ozone involve sanitation, and are conducted safely
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Levels of ambient gaseous ozone in plant air are always continually monitored and controlled to below OSHA Permissible Exposure Levels (PEL)
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Aqueous ozone systems typically are controlled by means of a dissolved ozone monitor/controller which provides automatic dose control proportionally to the water flow regulating the ozone levels in the water to between 1.5 and 3.0 PPM
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Gaseous ozone can be applied in controlled environments for microorganism control, spoilage reduction which results in increased shelf-life
Ozone as a Sanitizer
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Ozone typically is applied as an aqueous product
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It can be hard-plumbed into existing sanitation lines as a centralized system
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It can be utilized with hand-held or fixed sprayers
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It can also be used as a flood or cascade
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Aqueous ozone is sprayed at low pressure (20 psi or less) in cold water (<70°F)
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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 and/or result in some off-gassing of ozone to plant air
Ozone Sanitizing Uses
History Ozone Use in Food Facilities
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Ozone-enriched cold water (aqueous ozone) can sanitize both food contact and non-food contact surfaces, as well as any other wettable area with sanitation needs
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Floors, walls, conveyor belts, drains, tables, cutting boards, all flat or vertical surfaces
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Flumes, tanks, carts, bins, basins
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Ozone use will reduce levels of fat, oil & grease on surfaces, and it will break down microorganism and biofilm build -up on all surfaces
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Its continuous use will sanitize floor drains with no adverse effect on wastewater treatment systems
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Over time, ozone helps to rid drains and plumbing of biofilm and other microorganisms that can migrate back into the processi ng area (esp. Listeria monocytogenes)
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Ozone is beneficial to sewage treatment systems because it adds dissolved oxygen to the wastewater to be treated
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Regular use of aqueous ozone throughout the plant will help to eliminate greasy film on facility floors
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Ozone can be safely used on wettable ceilings and walls to reduce and remove biofilms and molds (especially in areas of high sugar products)
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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
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Ozone is used to reduce bacterial buildup in RO modules
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Early 1900s – German food plants; later German brewery cellars (mold control)
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Aqueous ozone gained popularity as a surface sanitizer in the USA directly after it was affirmed to be GRAS for direct food contact in 1997 (EPRI Expert Food Panel)
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Food Additive Petition submitted to FDA by EPRI, Aug. 2000; FDA approved ozone as an Antimicrobial Agent for direct contact with all foods (June 26, 2001)
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First adopters for surface sanitation were US wineries
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An estimated 4,000 – 5,000 US wineries utilize ozone today for surface sanitation in lieu of chlorine, and many utilize it for CIP of the filler lines and transfer lines
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Not only are levels of microorganisms, biofilms, molds, etc., diminished, but at least one chlorinated byproducts (tricloroanisole) that imparts off-tastes to wines no longer is produced
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Multiple food processing plants utilize aqueous ozone for surface sanitation, direct food contact and CIP; others utilize gaseous ozone in controlled environments for spoilage reduction and to increase shelf-life
Ozone Sanitizing in Food Plants
Other facilities utilizing ozone for surface sanitation include:
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Cheese processing plants; Eggs and Diary
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Raw and RTE meat and poultry processing plants
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Produce packers, produce processors
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Seafood processors
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Certified organic facilities
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Ozone sanitizing is part of many food processors’ HACCP and HARPC programs
Ozone Sanitizing in Industrial Applications
Other facilities utilizing ozone for various sanitation processes include:
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Pharmaceutical processing facilities
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High purity water for biotech processors
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High purity water for semiconductor producers
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Cosmetic processors
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Process Water Recycling
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Anywhere wettable surfaces need to be sanitized
Ozone Safety & Control
Ozone Material Compatibility
Ozone SDS
Ozone (Gaseous)
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OSHA PEL: 0.1 PPM 8 hour
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OSHA STEL: 0.3 PPM 15 min
Ozone (Aqueous)
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OSHA PEL: none established
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OSHA STEL: none established
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Eye Contact:: may cause mild irritation; not expected
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Ingestion Hazard: not ingested during application
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Inhalation Hazard: not likely; exposure to aerosolized aqueous ozone could become irritating
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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
The following list of materials commonly found in food processing plants have been life-tested or observed under actual use (15 years) in food processing plants to be unaffected by Aqueous Ozone Systems (2.0 – 3.0 PPM dissolved aqueous ozone)
Material List
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Stainless Steel (304, 316 and foil)
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Aluminum (all grades)
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Concrete, Painted Surfaces, Wood
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Painted Concrete
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Plastics: ECTFE, PTFE, PVC, PVDF, HDPE (Polyethylene)
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Gaskets: FPM (Viton), EPDM
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Rubber Modified Vinyl
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Galvanized Steel
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Glass
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Mild steel may experience surface rusting similar to exposure to plain water
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Natural latex rubber is not suitable for use with aqueous ozone
Regulatory Agencies
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FDA – regulates and allows ozone contact with foods (F&V, Seafood, Shell Eggs, Bottled Water)
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USDA/FSIS – regulates and allows ozone contact with meats, poultry and egg products
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USDA National Organic Program (NOP) – allows ozone for organic food contact
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EPA – regulates ozone generators under FIFRA (Surface Sanitation and Potable Water)
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OSHA – regulates ozone in workplace air
Regulatory Summary – FDA
21 § CFR 129.80 (3/15/1977; amended 4/4/2012)
Bottled water plant sanitizing of contact surfaces and any other critical area
0.1 PPM ozone-enriched water solution for at least five minutes (Ct value of 0.5 mg-min)
21 CFR §173.368 (6/26/2001)
FDA Secondary Direct Food Additives Permitted in Food for Human Consumption
Ozone may be safely used in the treatment, storage, and processing of foods, including meat and poultry
Ozone is used as an antimicrobial agent in accordance with current industry standards of good manufacturing practice
21 § CFR 178.1010 (b) (1, 3, 9, 30, 38) (3/16/1977) “Category Three Certification”: <15 cfu per cm for Yeast, Mold, Bacteria; No rinse
§178.1010 (b): “The solutions consist of one of the following, to which may be added components generally recognized as safe (GRAS) and components which are permitted by prior sanction or approval.”
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(1) 200 PPM chlorine
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(3) 25 PPM iodine (iodophore)
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(9) 200 PPM quaternary ammonia compound
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(30) 400-600 PPM peroxide
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(38) 128-156 PPM peroxyacetic acid
Ozone is (GRAS) and listed under prior sanction (USEPA/FIFRA) Standard Dose 1 -3 PPM Ozone
Regulatory Summary – USDA
Regulatory – USDA – 2
November 27, 2001, the American Meat Institute filed a letter with USDA/FSIS requesting interpretation of the scope of the FDA rule allowing the use of ozone as an antimicrobial agent
USDA/FSIS determined that, “The use of ozone on raw and ready-to-eat meat and poultry products just prior to packaging is acceptable,” and that there are “no labeling issues in regard to treated product”
USDA/FSIS Directive 7120.1 (12/17/02) (Revised 3/3/16)
“The attachment below identifies the substances that have been accepted since January 2000 by FSIS as safe and suitable for use in the production of meat and poultry products”
(Attachment 1) Antimicrobial – Ozone
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All Meat and Poultry Products
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In accordance with current industry standards of good manufacturing practice
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Reference 21 CFR § 173.368
USDA National Organic Program (NOP) Allowed
Ozone is listed in the NOP Final Rule (§ 205.605 (b) (20) pg. 437 – Nonagricultural (non organic) substances allowed as ingredients
in or on processed products labeled as “organic” or “made with organic (specified ingredients or food group(s))”
◦ (b) Synthetics allowed: (20) ozone
Prior to 1998, the USDA “White Book” listed authorized non-food surface contact compounds (including those for which sanitation claims were made) for meat or poultry
1998: NSF took responsibility for USDA “White Book”, updated listing, and
NSF encourages 3rd party testing to add candidates to the list and for approval by EPA OPP Disinfectant Tech Service Science Section (DIS/TSS) for no-rinse surface sanitation compliance
(Although recommended, this is not mandatory)
Regulatory Summary – EPA
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EPA regulates ozone as a pesticide- producing device
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Ozone generators must be registered by the EPA under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)
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Each Ozone Generator Manufacturer has a unique EPA registered establishment number as a pesticide-producing device
Regulatory – EPA – 2
For no-rinse surface sanitation compliance the USEPA/FIFRA Office of Pesticide Programs (OPP) Disinfectant Technical Science Section (DIS/TSS) requires:
1.Antimicrobial efficacy data determined by AOAC International methods
2.Toxicological profiles
3.Environmental impact information
4.Specific label information and directions for use
Ozone Generators are recognized by the EPA as antimicrobial producing devices per EPA documentation published in 1976, with an EPA Establishment Number necessary for compliance.
A viable ozone system is compliant with items 1-4
Some Ozone Systems are listed in the “NSF White Book”
Regulatory Summary – OSHA
3rd Party Aqueous Ozone Testing
OSHA has two ozone standards to protect plant workers from exposure to harmful levels of ozone in facility air:
Permissible Exposure Level (PEL):
◦ 0.1 PPM ozone (by volume). Time-weighted average over an 8-hour work day, 5-days per week
Short Term Exposure Level (STEL):
◦ 0.3 PPM ozone (by volume) for no longer than 15-minutes, not to be exceeded more than four times per day.
These OSHA standards have been adopted worldwide wherever ozone is used commercially
Adherence to these allowable ozone exposures ensures that workers will never be exposed to toxic levels of gaseous ozone during working hours.
Ozone systems with an aqueous ozone output of 1.5-2.0 PPM dissolved ozone were 3rd Party tested by NSF Toxicology Group for antimicrobial efficacy and worker safety
Antimicrobial Efficacy Protocols
DIS/TSS-1 (AOAC Official Method 961.02, Germicidal Spray Products as Disinfectants, for both broad-spectrum and hospital/medical environment efficacy claims) was chosen by the Microbiology and Toxicology Groups at NSF as the best testing protocol efficacy testing of aqueous ozone sanitizing on hard surfaces
NSF also chose DIS/TSS-4 (AOAC Method 960.09 Germicidal and Detergent Sanitizing Action of Disinfectants) for additional efficacy testing
NSF conducted studies according to EPA-established AOAC Official Methods 961.02 & 960.09, Germicidal Spray Products as Disinfectants, and Germicidal & Detergent Sanitizing Action of Disinfectants test procedures
3rd Party Aqueous Ozone Testing Antimicrobial Efficacy Results
AOAC 961.02 Results
Salmonella choleraesuis
Staphylococcus aureus
Pseudomonas aeruginosa
Trichophyton mentagrophytes
6 log reduction (99.9999%)
6 log reduction (99.9999%)
6 log reduction (99.9999%)
6 log reduction (99.9999%)
180 seconds
600 seconds
300 seconds
30 seconds
- Additional evaluations as per AOAC 961.02 Results
Campylobacter jejuni
Aspergillusflavus
Brettanomycesbruxellenis
Listeria monocytogenes
4 log reduction (99.99%)
4 log reduction (99.99%)
4 log reduction (99.99%)
4 log reduction (99.99%)
180 seconds
300 seconds
180 seconds
180 seconds
AOAC Method 960.09 Results
Escherichia coli
5 log reduction (99.999%)
30 seconds
3rd Party Aqueous Ozone Testing
Ozone Safety
Protocol
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NSF performed safety testing based on Hazard Communications Standard as promulgated through the Occupational Safety and Health Act (OSHA) of 1970 and documented in the Code of Federal Regulations, Title 29.
Results
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“It is the professional opinion of the Toxicology Group, LLC that DEL Ozone devices deliver a consistent applied ozone dose which meets both the critical level required to ensure the antimicrobial efficacy claims while still maintaining exposures below the OSHA Permissible Exposure Limit (PEL). Their product literature has provided sufficient information characterizing the physical and chemical hazards associated with use of their devices thereby allowing the employer adequate guidance to put in place a hazard communication program around the use of this device as required by the Hazard Communication Standard.”
Antimicrobial Studies
Antimicrobial Validation for Cryptosporidium parvum Reduction by NSF International – Low Dose Ozone
Pass compliance requires a 3 log (99.9%) reduction of Cryptosporidium parvum
Actual Microbial Reductions in 30 Seconds
Cryptosporidiumparvum
3.0 log (>99.9%)
Antimicrobial Studies
Bacillus subtilis
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“It is evident that ozone is superior to hydrogen peroxide in killing bacterial spores. Hydrogen peroxide at ~10,000-fold higher concentration was less effective than ozone against Bacillus spores. The comparatively low concentration needed to eliminate large populations of spores at ambient temperature in short time periods makes ozone best suited for industrial settings.”
- M.A. Khadre, A.E. Yousef, International Journal of Food Microbiology 71 (2001) 131–138
Antimicrobial Studies
B. cereus
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0.12 mg/l @ 5 minutes (CT 0.6) @ 28°C = > 2 log
- M.A. Khadre, A.E. Yousef, International Journal of Food Microbiology 66 (2001) 1247
B. cereus
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11.0 mg/l @ 1 minutes (CT 11.0) @ 22°C = > 6 log
- M.A. Khadre, A.E. Yousef, International Journal of Food Microbiology 71 (2001) 131
“Both studies provide statistical comparison only; therefore the ozone was not optimized, it is very likely more efficient and should be re-evaluated for optimum CT value and efficacy for Bacillus“
-Per Dr. Ahmed Yousef, February 2009
Antimicrobial Studies
Efficacy of Ozone Against Escherichia coli O157:H7 on Apples
Apples were inoculated with Escherichia coli O157:H7 and treated with aqueous ozone
The corresponding decreases in counts of E. coli O157:H7 during 3-min treatments were 3.7 and 2.6 log 10 CFU on apple surface, respectively, compared to , 1 log CFU decrease in the stem-calyx region in both delivery methods.
-M. ACHEN AND A.E. YOUSEF JOURNAL OF FOOD SCIENCE—Vol. 66, No. 9, 2001
Skid-Mounted Recirculating Aqueous Ozone Sanitation Systems
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Pre-plumbed and Skid-mounted
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Integrated Onboard Oxygen System
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Automatic Variable Flow Rate
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Automated Proportionally Controlled Ozone Dose
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Fully Automated Control System
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HMI Touch Screen Control Panel (on larger models)
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Self-diagnostic Switching
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Oxygen Gas Flow Meter
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Consistent Strength & Efficacy
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Integrated Ozone Management System
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Water Pump
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Dissolved Ozone Monitor/Controller
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Ozone Degas System and Thermal/Catalytic Ozone Destruct
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Direct Food Contact, Surface Sanitation, CIP/SIP and Product Water
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Kills all known pathogens including Listeria, Salmonella and E. Coli
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Sanitizes Surfaces on Contact
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Destroys Pesticide Residuals
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Breaks Down and Destroys Biofilm
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Eliminates Chemical Use, Handling, & Storage
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Greater Microbial Reduction than Chlorine, Chlorine Dioxide and PAA
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Complete Online Monitoring & Control
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Precise Process Control
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FDA & USDA Approved for Food Contact
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EPA Approved Surface Sanitizer
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100% Organic Certified