1. Ozone
Secondary Disinfection
System
for
Public Swimming Venues
Under MAHC Compliance
January 1, 2013

2. Public Health Responsibility
• Swimming is the third most popular sport in the
United States; encompassing all age groups
• It is estimated that there are about 360,000 public
pools in the U.S.
• Considering that most public swimming venues are
essentially communal baths, there is an enormous
task to protect public health from communicable
diseases and other health hazards
• Approved technologies currently available to help
provide a safe and healthy aquatic experience to all
swimmers should not be ignored
2

3. Cryptosporidium parvum Outbreaks
136 outbreaks of cryptosporidiosis worldwide from 1988 to 2004 (68 in U.S.) with 92% in disinfected venues
- Centers for Disease Control in Atlanta - 2008 reported 10,500 cases 3

4. Water Quality Issues and
Cryptosporidium parvum Outbreaks
• CDC swimming pool surveillance reports show that of the 21,500
inspections conducted between May and September of 2002, water
chemistry violations were found at 38.7% of these facilities, 14.3%
of the violations were for inadequate disinfection levels at
therapy pools
(CDC Surveillance Data from Swimming Pool Inspections --- Selected States
and Counties, United States, May – September 2002. 2003. MMWR 52(22);
513-516)
• During 2008, inspectors in 15 jurisdictions performed 120,975
inspections and found 12,917 (10.7%) identified disinfectant
level violations
(CDC Surveillance Data from Swimming Pool Inspections --- Selected States
and Counties, United States Morbidity and Mortality Weekly report (MMWR) May
21, 2010 / 59(19);582-587)
• In one of the largest outbreaks reported, approximately 2,300
persons developed cryptosporidiosis following exposure to a New
York spray park
(Surveillance for Waterborne Disease and Outbreaks Associated with
Recreational Water Use and Other Aquatic Facility -- Associated Health Events
--- United States, 2005—2006 MMWR Surveill Summ. September 12, 2008 /
57(SS-9);1-38) 4

5. Recreational Water Illness
• Chlorine has been the standard water treatment chemical for
public pools since 1961 (U.S. Public Health Service)
• Chlorine is effective in reaching certain water quality standards,
however scientists are learning more about its limitations and
hazards in public swimming venues
• Recreational Water Illness (RWI) has become wide spread in
the US in public pool venues and is increasing annually; posing
a significant public health and liability risk
• RWI is a term coined by the Centers for Disease Control and
Prevention (CDC) to describe illnesses caused by
microorganisms as well as those from chloramines
– Some microorganisms including Pseudomonas aeruginosa, E. coli,
Staphylococcus aureus, Giardia and Cryptosporidium parvum
(Crypto), can cause serious illness in swimmers
– Chloramines can cause breathing disorder illnesses sometimes
called “Swimmers Asthma”
5

6. Model Aquatic Health Code
(MAHC)
• Currently there is no uniform national standard for
water quality or RWI response
• To address this, the CDC has developed a Model Aquatic
Health Code (MAHC)
• State and Federal public health officials along with
industry professionals from across the US, have
participated for five years in the creation of the MAHC’s
twelve modules which include the best available
standards and practices for protecting public health
• The MAHC is formatted to be easily adopted by state
and local health departments
• The CDC states it is “intended to transform the typical
health department program into a data-driven,
knowledge-based, risk reduction effort to prevent
disease and injuries and promote healthy recreational
water experiences” 6

7. MAHC Disinfection &
Water Quality Module
The Disinfection and Water Quality Module contains
requirements for new or modified construction
that include:
• Primary disinfectant levels set
• Secondary disinfection required for “increased
risk” aquatic venues such as interactive features,
spray pads, wading pools, and other venues
designed primarily for diaper-aged children as well
as therapy pools
• Combined chlorine maximum levels set
• Prohibition of cyanuric acid in Indoor facilities and
“increased risk” aquatic venues
7

8. Secondary Disinfection
Systems SDSs
• When the MAHC is published in spring of 2013, it will include a
section on the importance of Secondary Disinfections Systems
(SDSs) to significantly reduce RWIs (caused by microorganisms
and chloramines)
• According to the MAHC
– All Secondary Disinfection Systems (SDSs) must be certified
to NSF/ANSI Standard 50 by an ANSI-Accredited third-party
testing and certification organization to verify that they
provide the minimum inactivation of Cryptosporidium
parvum in the full flow
– All Secondary Disinfection Systems (SDSs) must provide a
minimum of 3 log (99.9%) inactivation of Cryptosporidium
parvum in the full flow, prior to return of the water to the
pool or aquatic feature at the minimum turnover rate
• Approved SDSs are Ozone systems and UV systems
8

9. MAHC Disinfection & Water
Quality SDS Aquatic Venues
The new construction or substantial renovation of the following
INCREASED RISK AQUATIC VENUES shall be required to use a
SECONDARY DISINFECTION SYSTEM after adoption of this CODE:
1) AQUATIC VENUES designed primarily for diaper-aged children
(children <5 years old), such as
a. wading POOLS,
b. water activity POOLS,
c. interactive water features with no standing water,
d. SPRAY PADs, and
2) Therapy pools
Optional SECONDARY DISINFECTION SYSTEMS may be installed on all
other aquatic venues not specified above to provide the same
quality of protection to bathers
9

10. Definitions of Ozone and UV
• Ozone is a gas that is dissolved in water to kill
microorganisms, destroy organics, and break
down chloramines by oxidation. This occurs
immediately at the ozone gas injection point,
and continues as the side-stream remixes with
the main return. A small residual (~0.1 PPM) of
dissolved ozone will enter the pool, providing
further oxidation of contaminants.
• UV light inactivates microorganisms and breaks
down chloramines with light energy. This
happens while the water is in the UV chamber
only, and as long as the water has no turbidity.
No further process occurs once the flow leaves
the chamber. UV provides no oxidation except
as trace amounts as a result of the formation of
a limited number of hydroxyl free radicals in or
near the UV chamber. 10

11. Properties of Ozone
• Ozone (O3) is a gas derived from oxygen which can be readily dissolved in
water
• Ozone has a fresh scent at low concentrations and smells pungent at higher
concentrations
• Gaseous Ozone dissolved in water is referred to as Aqueous Ozone (which has
no odor)
• Ozone is a powerful antimicrobial oxidizer and sanitizer
• Aqueous Ozone is an effective micro-flocculant
• Aqueous Ozone is an effective anti-foaming agent
• Aqueous Ozone is an effective antimicrobial agent
• 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 microorganisms to be destroyed
• Ozone is compatible with Chlorine in Swimming Pools
11

12. Benefits of Ozone
• Ozone controls the chloramine levels in the water on average to 0.2
PPM or less
• Ozone can eliminate “shock-oxidizing” for chloramine reduction
• Ozone offers significantly more oxidation than free available chlorine
(FAC) alone
• Ozone provides a minimum 3 log (99.9 percent) kill of
Cryptosporidium parvum and other RWI pathogens in a side-stream
applied single-pass
• Ozone will destroy emerging pharmaceutical pollutants such as
endocrine disruptors
• Ozone provides micro-flocculation to aid filtration and noticeably
improve water clarity (eliminates foam from spas)
• Ozone destroys biofilm
• Chlorine consumption is reduced by 50-75% while still maintaining an
FAC residual; at the lowest applied O3 dose of 1.6 PPM
12

13. Can Ozone Stand Alone?
• Ozone’s role is actually as the primary sanitizer, and ozone
disinfection will pass into the pool, but maintaining an ozone
residual in the pool that is high enough to ensure continuous
in-pool protection from bather-to-bather cross-contamination
can be expensive; and present the risk of ozone off-gas
• With current technology it’s impractical to expect ozone to
perform as a stand-alone sanitizer in a public swimming
venue without a residual halogen in the pool (0.3-1.0 PPM)
• A low residual of chlorine, in conjunction with an
appropriately sized and maintained ozone system, will be
virtually undetectable even by the most sensitive bathers,
and keep operating costs very low
13

14. How is Ozone Measured?
• Dissolved ozone is measured by an
Oxidation Reduction Potential (ORP)
monitor/controller in a swimming pool
• 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
14

15. Breakdown of Pool Types
Based on bather load and water
temperature, four categories are
identified
1. Recreation/Lap Pool (78-85°F)
2. Therapy/Swim School Pool (86-94°F)
3. Wading Pool/Spray Pad (80-88 °F)
4. Spa (94-104°F)
15

16. Ozone Sizing Parameters
• In each of the 4 categories, 1.6 PPM Ozone is applied
to the total volume of the pool based on time, using a
conversion constant of 0.227
• The time value changes with each category (the
higher the temperature and bather load, the more
ozone is required)
1. Recreation/Lap Pool 1.6PPM/24 hr (1440 min)
2. Therapy/Swim School Pool 1.6PPM/12 hr (720 min)
3. Wading Pool/Spray Pad 1.6PPM/4 hr (240 min)
4. Spa 1.6PPM/2 hr (120 min)
16

17. Ozone Retention Parameters
• Ozone is measured by the combination of
applied Ozone Dose and Retention Time in
the side stream (CT Value [Concentration X
Time])
• Retention time for all pool types is a
minimum of one minute, measured
immediately at the injector outlet in the
sidestream, inclusive of the volume of the
degas tank, volume of the sidestream
plumbing and the volume of the
mainstream plumbing just prior to the
halogen feed location and before entering
the pool
17

18. Sample Pool Ozone Sizing
• Pool Example
– 100,000 Gallon Recreation/Lap Pool
• Ozone dose is 1.6 PPM (D)
– Volume/Minutes = Ozone Dose Flow (F)
• 100,000/1440 = 69 GPM (F)
– Generator Sizing Formula: D * F * 0.227 = Grams per
hour Ozone Required
• 100,000/1440 * 1.6 * 0.227 = 25 grams/hour
– Retention Tank Sizing Formula: F * T (minutes) = Size of
Retention in Gallons
• 69 * 1 = 69 gallons
18

19. Ozone Regulatory
1976 EPA Approves Ozone as an Antimicrobial Oxidizer Device
1982 IBWA Bottled Water Association Approve Ozone as an
Antimicrobial for Product, and Disinfectant for Filler Lines
1999 EPA Lists Ozone as Safe for Surface and Ground Water
2001 FDA/USDA Approve Ozone as an Antimicrobial Food
Additive
2001 FDA/USDA Approve Ozone as a Food Contact Surface
Disinfectant
2001 USDA National Organic Program Allows Ozone as an
Antimicrobial Food Additive and Food Surface Disinfectant
2010 Ozone is added to the FDA Model Food Code as an
approved antimicrobial surface sanitizer
2012 Ozone is recommended as a Secondary Disinfection 19
System in the Model Aquatic Health Code

20. Ozone Safety
EPA approved
• As a pesticide, ozone equipment must be registered by the EPA under the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). DEL Ozone is an
EPA registered establishment (EPA Estab. No. 071472-CA-001).
OSHA Regulations for Ozone (Gaseous Only)
• Health Hazard Data
– Inhalation /Respiratory System, Eyes, Blood
• PEL (Permissible Exposure Limit)
– 8 hour Time Weighted Average 0.1 PPM Vol.
• STEL (Short Term Exposure Limit)
– 15 Minute 0.3 PPM Vol.
• IDLH (Immediately Dangerous to Life and Health)
– 5 PPM
No OSHA Regulations apply to Aqueous Ozone; it is not harmful to humans
20

21. Ozone safety
• Vacuum Generated Ozone Ensures User Safety
– No ozone gas can escape in the event of loss of vacuum
– Systems provide complete isolation in the event of any
shutdown
• Vacuum Operation Optimizes Mass-transfer
Efficiency
– Venturi Injectors operate under negative pressure; a
vacuum ozone system provides ease of injector
adjustment and operation
– Mass-transfer is optimized and consistent
– Optimized mass-transfer results in more dissolved ozone
– Undissolved ozone is degassed and destroyed 21

22. Definition of Sanitizers &
Disinfectants
A Sanitizer is one of the three groups of antimicrobial
agents registered by the USEPA for public health
uses.
Disinfectants are antimicrobial agents that are applied
to non-living objects to destroy microorganisms, the
process of which is known as disinfection.
Sanitizers are substances that reduce the number of
microorganisms to a safe level.
The main difference between a sanitizer and a
disinfectant is that at a specified use dilution, the
disinfectant must have a higher kill capability for
pathogenic bacteria compared to that of a sanitizer.

23. Ozone is an EPA Approved
Antimicrobial, Disinfectant &
Sanitizer by all Definitions
Ozone Performs these
Functions as an Oxidizer
In Use for over a Century
Worldwide as a Water
Disinfectant

24. Ozone Biocidal Behavior
Electron Micrographs of E. coli before/after ozone treatment
E. coli dried as a biofilm on a porous surface
Before ozone treatment After ozone treatment
Electron Magnification Scale of Measure Working Distance
Sequential
Beam Power One Micrometer
(micron)
1. Ozone oxidizes cell membranes, causing osmotic bursting (instantaneously)
2. Ozone continues to oxidize enzymes and DNA
24

25. Public Bath Tubs
Ozone Anti-Microbial Validation under ANSI/NSF Protocol P308
Pass compliance requires a 3-log (99.9%) reduction of E. coli, Staphylococcus
aureus, Pseudomonas aeruginosa, Trichophyton mentagrophytes and Candida
albicans in 30 minutes
Actual Microbial Reductions in 30 Minutes
E. coli 4.7 log (>99.99%)
Staphylococcus aureus 4.7 log (>99.99%)
Pseudomonas aeruginosa 3.2 log (>99.9%)
Trichophyton mentagrophytes 4.0 log (99.99%)
Candida albicans 4.7 log (>99.99%)
Test Parameters
• Water temperature @ 93° F
• 20 PPM oil insult
• 1.1 PPM side-stream applied ozone dose Low Dose Ozone
• Microorganism destruction was measured in the tub
25

26. Public Swimming Venues
Ozone Anti-Microbial Validation under ANSI/NSF Standard 50,
Annex H
Pass compliance requires a 3-log (99.9%) reduction of Pseudomonas
aeruginosa and Enterococcus faecium in 30 minutes
Actual Microbial Reductions in 6 Minutes
Pseudomonas aeruginosa 6.6 log (>99.9999%)
Enterococcus faecium 6.7 log (>99.9999%)
Test Parameters
• Water temperature @70° F
• 20 PPM oil insult
• 9 PPM Urea insult
• 1.6 PPM side-stream applied ozone dose
• Microorganism destruction was measured in the pool
26

27. Public Swimming Venues
Ozone Antimicrobial Validation for Cryptosporidium parvum Reduction tested
by NSF International
Pass compliance requires a 3 Log (99.9%) reduction of Cryptosporidium
parvum
Actual Microbial Reductions in 30 Seconds
Cryptosporidium parvum 3.0 log (>99.9%)
Test Parameters
• Water temperature @76° F
• 1.6 PPM side-stream applied ozone dose
• Crypto measurements were taken on a single pass [measured
after side-stream is diluted in full flow]
27

28. Side-Stream Applied
Single Pass
28

29. CT Values for Cryptosporidium
parvum Inactivation
CT Value
Concentration times Time
(PPM * Minutes Exposure = CT Value)
Chlorine
CT is 15,300 [20 PPM for 13 hours (780 minutes)]
Aqueous Ozone
CT is 0.72 (1.257 PPM for 34 seconds)

30. How Ozone is Made
• Oxygen molecules (O2) split
by adding energy, resulting
in two individual oxygen
atoms (O1)
• Oxygen atoms (O1) unite
with other oxygen
molecules (O2) to produce
Ozone (O3)
• (O1) + (O2) = (O3)
30

31. How Ozone Works
• 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
• During an oxidation reaction,
organic molecules are changed
or destroyed and dissolved
metals are no longer soluble
31

32. MAHC Ozone System
Requirements
An ozone system shall be a complete system consisting of the following
(either skid-mounted or components):
1) Ozone generator
2) Injector / injector manifold
3) Reaction tank (contact tank) / mixing tank / degas tower
4) Degas valve (if applicable, to vent undissolved gaseous ozone)
5) Ozone destruct (to destroy undissolved gaseous ozone)
6) ORP monitor / controller
7) Ambient ozone monitor / controller
8) Air flow meter / controller
9) Water backflow prevention device in gas delivery system
32

33. Basic Ozone System
33

34. Very Small Ozone System
34

35. Small Ozone System
35

36. Large Ozone System
36

37. Ozone Generation System
Components
37

38. Ozone Gas Dissolution
38

39. Ozone Reaction in Water
39

40. Degas Undissolved Ozone
40

41. Destroy Undissolved Ozone
41

42. Flange to Flange Ozone Skid
42

43. Ozone Systems Made Simple
• Complex ozone systems of the past have been
replaced by modern, compact, affordable
systems
• Skid-mounted, plug and play ozone systems are
the norm for 100,000 gallon pools and smaller
• Flange to flange hook-up to the main return line
decreases cost and complexity of the installation
• The system’s 4’X3’ footprint is compact to easily
fit into the equipment room
43

44. Costs and Savings with Ozone
Assumptions
• 100,000 gallon indoor pool
• $250/ 10 PPM shock/100K Gal (chlorine @ $2.50/gal)
• Shock (without ozone) estimate 52 per year = $13,000
• Annual chlorine use estimate is based on chlorine cost @ $2.50/gal
Bather load assumptions
• 100 bathers/day = 1,825 gals @ $2.50 = ~$4,563
• 200 bathers/day = 3,650 gals @ $2.50 = ~$9,125
• 300 bathers/day = 5,475 gals @ $2.50 = ~$13,687
• 400 bathers/day = 7,300 gals @ $2.50 = ~$18,250
• Chlorine reduction with ozone is average 50%
Ozone System Cost Estimates
• End-user purchase price $30,000.00
• Annual power consumption at 0.12 per kWh $2,375.00
• Annual Maintenance parts $300.00
Savings Estimates
• Eliminate shock treatments and labor costs $13,000 plus labor cost savings
• Chlorine Reduction at 50% avg. 100 bathers/day $2,281
400 bathers/day $9,125 savings
Return on Investment (ROI) approximately 1.5 - 2 years
44

45. Ozone Compatibility with Cl and Br
• Ozone’s reaction with chlorine is minimal
• Ozone will break down chloramines
• Ozone provides the main oxidation and disinfection
in the pool while the chlorine provides a chemical
residual
• Ideal Chlorine residual is 0.3 – 1.0 PPM
• It is not recommended that ozone be used in
conjunction with bromine. When used with
bromine, ozone oxidizes “spent” bromine (bromide)
back to useful bromine. This depletes the ozone
before it can oxidize the organic contaminants in
the water, and significantly reduces ozone’s
efficacy. 45

46. Ozone compared to UV
Sterilizers
Both Ozone and UV provide very effective Crypto reduction as documented by NSF Standard
50, Annex H
Ozone Destruction of Chloramines
• Ozone breaks down Chloramines by oxidation in two ways
– By breaking down the N-Cl bonds of the Chloramine molecules through oxidation by
ozone (this process occurs at the point of ozone injection and continues the
oxidation process as it passes at low levels into the pool)
– Ozone also forms hydroxyl free radicals, adding to the Chloramine oxidation process
• Ozone reduction of Chloramines is also a function of its powerful oxidation of
chloramine-producing organic contaminants; eliminating their initial production
UV Destruction of Chloramines
• UV can break down Chloramines in two ways
– By breaking the N-Cl bonds of the Chloramine molecules with UV light energy (this
process occurs in the UV chamber only)
– By forming small numbers of hydroxyl radicals with UV light energy, which oxidize
Chloramines (this process occurs within nanoseconds, effectively occurring only in,
or very near the UV chamber)
• UV produces very little oxidation to affect organics in the water 46

47. Ozone and UV comparison
OZONE UV
 Ozone kills cryptosporidium parvum  UV inactivates cryptosporidium parvum
 Ozone kills microorganisms  UV inactivates microorganisms
 Ozone is a powerful oxidizer UV is not an oxidizer
 Ozone passes into the pool at low levels to provide UV affects the water only as it passes through the UV
additional oxidation chamber
 Ozone functions well in cloudy water, and is a Only clear water can be effectively dosed with UV;
micro-flocculent, which aids water clarification cloudiness in the water can absorb the UV light
 Ozone oxidizes the organics and inorganics that UV breaks down chloramines that have been previously
create chloramines, eliminating their production created
 Ozone utilizes ORP (REDOX) to measure the UV systems utilize a UV intensity meter which
cleanliness of the water measures the UV dose regardless of water quality
 Ozone’s reaction with free available chlorine (FAC)  UV can break down free available chlorine in the
is very slow and in a pool will not affect the FAC
water while it breaks down chloramines
levels; only chloramine destruction
Mercury vapor lamps are replaced @ 3-12 mos.;
 Ozone cells require no replacement; require annual disposal procedures must be considered as lamp gases
periodic cleaning; no hazardous components are considered hazardous waste
 Ozone destroys biofilm UV does not affect biofilm
 Ozone destroys Humic and Fulvic Acid UV does not affect Humic and Fulvic Acid 47

48. Ozone and UV Together
• Ozone and UV may be used together to create a
synergistic approach to water sanitation
• This process has been in use for drinking water,
food processing, and waste water for many years
• It is one of several advanced oxidation processes
(AOPs) that are in commercial use today in selected
industrial processing
• The technology has rarely been used in public pools
to date, but with the advent of improved
technology and cost reduction, perhaps it will be
the wave of the future for RWIs and chloramine
elimination
48

49. Indoor Swimming Venues
KEY LIME COVE INDOOR WATERPARK, Gurnee,
IL
49

50. Outdoor Swimming Venues
Atlantis Resort, Paradise Island, Bahamas
Outdoor Lagoon Pool
50

51. Conclusion
• Advances in Ozone Technology have
provided the means for affordable
and effective ozone systems
• Commercial Swimming Venues
benefit from safer, cleaner and more
manageable water, free of
chloramines and noticeably clearer
51

52. References and Credentials
• INTERNATIONAL OZONE ASSOCIATION PROCEEDINGS OF THE INTERNATIONAL
OZONE ASSOCIATION - PAN AMERICAN GROUP ANNUAL CONFERENCE, September
19-22, 2010, Bellevue, Washington – Peer reviewed and Copyrighted © 2010
• DISINFECTION AND WATER QUALITY TECHNICAL COMMITTEE - MODEL AQUATIC
HEALTH CODE – Peer reviewed 2010
• RIP G. RICE, PH.D., R.I.C.E. INTERNATIONAL GLOBAL OZONE CONSULTANT – Peer
reviewed 2010
• HAAG, W. R. AND HOIGNE, J.(1984) 'Kinetics and products of the Reactions of Ozone with
Various forms of Chlorine and Bromine in Water', Ozone: Science & Engineering, 6: 2, 103 -
114
• AIR LIQUIDE AMERICA CORP, Chicago Research Center, James T.C. YUAN, Ph.D., ca 2000
• NSF INTERNATIONAL ANSI/NSF Protocol P308 - Validation
• NSF INTERNATIONAL ANSI/NSF Standard 50 - Validation
• NSF INTERNATIONAL ANSI/NSF Standard 50 – Annex H (Microbial Efficacy and Ozone
Safety) – Validation
• NSF INTERNATIONAL Report J-00047649 (Cryptosporidium parvum) - Validation
• NSF INTERNATIONAL TOXICOLOGY GROUP 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 – Compliant
• USEPA registered establishment under the Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA) - Compliant
• USEPA/FIFRA Office of Pesticide Programs (OPP) Disinfectant Technical Science Section
(DIS/TSS) - Compliant

53. Beth Hamil
Vice President
Corporate Compliance
DEL Ozone
800 676 1335 ex. 222
805 441 4444
beth@delozone.com
Ozone liaison for:
 Water Quality Technical Committee of the MAHC
 APSP Recreational Water Quality Committee
 ANSI/NSF Standard 50 Joint Committee
 FDA Food Code
 State Health Department Consultant for ozone applications
53