For reasons of economy, this document is printed in a limited number. Delegates are 

kindly asked to bring their copies to meetings and not to request additional copies.

I:\MEPC\60\2-4.doc 

INTERNATIONAL MARITIME ORGANIZATION

IMO 

E

MARINE ENVIRONMENT PROTECTION 

COMMITTEE 

60th session 

Agenda item 2 

MEPC 60/2/4

19 August 2009

 Original: ENGLISH

HARMFUL AQUATIC ORGANISMS IN BALLAST WATER 

Application for Basic Approval of the DESMI Ocean Guard 

Ballast Water Management System 

Submitted by Denmark 

SUMMARY

Executive summary: This document contains non-confidential information for Basic Approval 

of the DESMI Ocean Guard Ballast Water Management System in 

accordance with the “Procedure for approval of ballast water 

management systems that make use of Active Substances (G9)” 

adopted by resolution MEPC.169(57). All relevant documents 

and the complete application dossier will be provided to 

the Marine Environment Division of the Organization for review by 

the GESAMP-Ballast Water Working Group. 

Strategic direction: 7.1 

High-level action: 7.1.2 

Planned output: 7.1.2.4 

Action to be taken: Paragraph 6 

Related documents: BWM.2/Circ.13; BWM.2/Circ.18 and MEPC 56/2/3 

Introduction 

1 Regulation D-3.2 of the International Convention for the Control and Management 

of Ships’ Ballast Water and Sediments stipulates that ballast water management systems which 

make use of Active Substances to comply with the Convention shall be approved by 

the Organization, based on a procedure developed by the Organization. 

2 The “Procedure for approval of ballast water management systems that make use 

of Active Substances (G9)” was adopted by resolution MEPC.169(57). Procedure (G9) defines the 

principal aspects to be documented by data or testing (MEPC 57/21, annex 1, paragraph 4.2.1) and 

some basic principles for risk evaluation (MEPC 57/21, annex 1, paragraph 5.3). According to 

section 6 of Procedure (G9), the Organization should evaluate the information provided in the 

application. 
MEPC 60/2/4 - 2 - 

I:\MEPC\60\2-4.doc 

3 According to BWM.2/Circ.13 and BWM.2/Circ.18, proposals for approval of ballast 

water management systems that make use of Active Substances need to be submitted to 

the Marine Environment Division of the Organization to be reviewed by the GESAMP-BWWG. 

4 The competent authority in Denmark has verified the application dossier prepared 

by DESMI Ocean Guard A/S and believes that it satisfies the data requirements 

of Procedure (G9) adopted by resolution MEPC.169(57). 

5 Denmark therefore submits the non-confidential part of the applicant’s dossier in the 

annex to this document for evaluation according to Procedure (G9). The complete dossier will be 

made available to the experts of the GESAMP-BWWG. 

Action requested of the Committee

6 The Committee is invited to consider the proposal for approval and decide as appropriate. 

***
MEPC 60/2/4 

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ANNEX 

NON-CONFIDENTIAL INFORMATION ON THE DESMI OCEAN GUARD 

BALLAST WATER TREATMENT SYSTEM 

1 SUMMARY............................................................................................................................. 3 

2 INTRODUCTION TO TECHNOLOGY............................................................................. 4 

2.1 Ultraviolet treatment (UV).............................................................................................. 4 

2.2 Ozone .............................................................................................................................. 5 

2.3 Filters .............................................................................................................................. 6 

2.4 Overview of the system .................................................................................................. 6 

2.4.1 System sizing .............................................................................................................. 8 

2.4.2 Brief description of the system ................................................................................... 8 

2.5 Detailed description of the system.................................................................................. 9 

2.5.1 Operational overview and process description ........................................................... 9 

2.5.2 Major components .................................................................................................... 12 

2.5.3 System requirements, monitoring and control, crew interaction .............................. 14 

2.5.4 System locations ....................................................................................................... 16

2.6 Operational safety features and alarms......................................................................... 16 

2.7 Procedures and management measures......................................................................... 16 

2.8 Evaluation of management measures............................................................................ 17 

2.9 Performance test............................................................................................................ 17 

2.10 System advantages........................................................................................................ 18 

3 DATA-SET FOR ACTIVE SUBSTANCES AND PREPARATIONS ............................ 18 

3.1 Chemical identification................................................................................................. 18 

3.2 Background to characterize reactive physical processes, relevant and other chemicals19 

3.2.1 Reactive physical processes...................................................................................... 19 

3.3 Advantages and considerations when using the O3/UV system ................................... 25 
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4 RISK ASSESSMENT........................................................................................................... 25 

4.1 Chemical characterization of treated ballast water ....................................................... 26 

4.2 Whole effluent ecotoxicity test ..................................................................................... 28 

4.3 Theoretical evaluation of fate and effect properties of Active Substances and potential 

by-products ................................................................................................................... 29 

4.3.1 Fate properties........................................................................................................... 29 

4.3.2 Persistence, Bioaccumulation and Toxicity (PBT)................................................... 31 

4.3.3 Endocrine Disrupting Chemicals (EDC) .................................................................. 31 

4.4 Ecotoxicity .................................................................................................................... 31 

4.5 Prediction of discharge and environmental substance concentrations: MAM-PEC.... 32 

4.6 Prediction of whole effluent discharge and environmental whole effluent concentration: 

MAM-PEC.................................................................................................................... 34 

4.7 Environmental risk assessment..................................................................................... 35 

4.7.1 Assessment of discharged substances....................................................................... 35 

4.7.2 Assessment of whole effluent ................................................................................... 36 

4.8 Overall conclusion on the environmental risk assessment ........................................... 37 

4.9 Risk to safety of ship..................................................................................................... 37 

4.9.1 Increased corrosion ................................................................................................... 37 

4.9.2 Fire and explosion..................................................................................................... 37

4.9.3 Storage and handling of the substances .................................................................... 38 

4.9.4 Contact with, or inhalation of, process products....................................................... 38 

4.9.5 Counter measures for Ozone leakage ....................................................................... 38 

4.9.6 Noise ......................................................................................................................... 38 

4.10 Human exposure scenario and risk assessment for crew and public ............................ 39 

4.10.1 Occupational exposure.......................................................................................... 39 

4.10.2 Exposure via the environment .............................................................................. 41 

4.10.3 Overall conclusion on the human exposure assessment ....................................... 41 

5 CONCLUSION..................................................................................................................... 44 

5.1 Test report data quality ................................................................................................. 44

5.1.1 DHI ........................................................................................................................... 44 

6 REFERENCES..................................................................................................................... 45 
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1 SUMMARY 

DESMI Ocean Guard A/S is applying for the Basic Approval of the DESMI Ocean Guard ballast 

water management system (BWMS) with the International Maritime Organization. 

The application of DESMI Ocean Guard for the Basic Approval of its ballast water management 

system DESMI Ocean Guard is based on the technologically safe and environmentally sound 

approach to abstain from any chemical preparations and avoidance of reactive intermediates with 

the potential to pose a risk to the environment and/or to human health. The DESMI Ocean Guard 

BWMS is designed to avoid reactive oxidants in ballast tanks or harbour areas by using UV-light 

and ozone in an advanced oxidation process. 

Based on definitions contained in the Methodology for information gathering and the conduct of 

work of the GESAMP (MEPC 58/2/7, annex 4), there are no Preparations used, but there is 

an Active Substance (ozone) and photons generated in situ by the treatment process of the 

DESMI Ocean Guard system. Relevant Chemicals are OH▪ radicals and a range of possible 

by-products are considered other substances. 

To evaluate the impact of ballast water treatment on the production of other substances, water 

samples were analysed chemically before and after the treatment process. For detailed 

information about the analysis, please refer to section 4 in this application. 

Under independent scientific examination, the risk characterization and risk assessment were 

conducted regarding risks to the safety of ship, to human health and to the aquatic environment. 

Analysis of the risk assessment demonstrates that no risks associated to the ship and its personnel 

neither to human health in general could be identified. Additionally, it can be concluded that 

from this treatment process, the magnitude of the hazard and the probability of risk exposure to 

the aquatic environment is of no concern. 
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2 INTRODUCTION TO TECHNOLOGY 

DESMI Ocean Guard A/S is applying for Basic Approval of the DESMI Ocean Guard Ballast 

Water Management System (BWMS) with the International Maritime Organization. 

The DESMI Ocean Guard BWMS is composed of pre- and after-treatment modules to disinfect 

aquatic species in the ballast water. The treatment comprises mechanical filtration in combination 

with a photo-catalysis based on advanced oxidation process (AOP) based on ozone and 

ultraviolet radiation (UV). 

Generated ozone is injected in the water flow; reaction takes place in an enhanced ozone reactor. 

Residual gaseous ozone is decomposed in an excess exhaust system from the enhanced 

ozone reactor. Soluted ozone remaining after the reactor is decomposed completely in the UV 

step, in an advanced oxidation process, leaving no residual ozone or other oxidants from the 

ballast water treatment process. 

Due to the highly efficient combination of low concentration ozone and UV radiation in an 

advanced oxidation process (AOP) ensuring oxidant-free treated water, the DESMI Ocean Guard 

technology can be viewed as a “stand-alone unit” without effect on ballast tank or the 

environment. Because the UV-C technology is very intense compared to the low ozone 

concentration in our system, even in water without oxidation potential residual oxidant levels are 

very low. 

2.1 Ultraviolet treatment (UV) 

Ultraviolet technology is proving more and more successful and is used as an acknowledged, 

cost-effective and reliable process. UV-C radiation as disinfection means is well known for 

almost a hundred years and is used widely in the disinfection of portable water, aquaculture 

waters, cooling water, hot water systems, ultra pure water, foodstuff industry, medicine, bottling 

of drinks, etc. It is used primarily wherever the microbiological requirements are particularly 

high, or where chemical disinfectants are unacceptable for quality or environmental reasons. 

It was found that especially a narrow band of wavelengths around 260 nanometer (nm) has 

a strong performance for disinfection, and are similar to the absorption curve of the DNA. The 

monochromatic low-pressure mercury germicidal lamps, which are used for UV-disinfection, 

have their maximum performance at a wavelength of 254 nm exactly in the optimal narrow band. 

The use of UV radiation as disinfection energy results in no change of the chemical compositions 

pH-value, temperature, salinity, taste, odour and colour of the solution being treated, and safety 

issues related to the handling and storage of Active Substances or other chemicals are eliminated. 

Ultraviolet disinfection requires a minimum dosage to be effective. The applied dosage is 

a function of the lamp intensity and the exposure time. These parameters are directly affected by 

equipment configuration, flow path of the water along the bank of lamps and the turbidity of the 

water to be disinfected. Compared to mid- or high-pressure lamps, low-pressure lamps can only 

operate with lower power intensity, but they have a much better efficiency of about 40%. Using 

high- or mid-pressure UV lamps, the operating costs will be higher but the number of needed 

lamps lower. 
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It is a scientifically well-known fact that resistance of organisms like bacteria, viruses, moulds or 

fungal spores to ultraviolet radiation is not developed. Most pathogenic germs are especially 

sensitive to UV-radiation. An important advantage of physical disinfection is that the sensitivity 

to UV still functions even when germs have already built up resistance to conventional 

disinfection measures such as alcohol, antibiotics, chlorinated chemicals, etc. 

To address all the mentioned needs, UV-radiation technology provides a powerful barrier to 

chemical contaminants while simultaneously disinfecting to avoid the dispersal of invasive 

aquatic species by ballast water from ships. 

The primary effect on organisms through short-wave and energetic UV-C radiation at 254 nm is 

based on a photo-chemical alteration of the DNA. The UV-C radiation is absorbed by pyrimidins, 

which form the basic elements of the organic bases of the DNA string. Through covalent 

bindings of two neighbouring bases like thymin, pyrimidin dimers are generated. These 

pyrimidin dimers prevent replication of DNA helix strings and cause mutations, which result 

from unsuccessful DNA string repair mechanisms. Dimers are called “bulky lesions”: they 

disturb the helical configuration of DNA by means of partial decartelization resulting in reduced 

base matching ability. In addition, the UV radiation may result in direct alterations of the DNA 

morphology, for example, singular or double string fractures. Double string fracture can not be 

repaired and lead to cell mortality. In general, UV radiation results in defects of DNA repair 

abilities. 

Part of the content for this explanatory section on UV was taken from the published and 

approved application “Harmful Aquatic Organisms In Ballast Water” from Germany [9]. 

2.2 Ozone

Ozone is a molecule that consists of three negatively charged oxygen atoms. The ozone molecule 

is very unstable and has a short half-life, causing it to fall back into its original form after 

a while, according to the following reaction mechanism: 

2O3 -> 3O2

Principally, an ozone molecule is nothing but an oxygen molecule that has received an extra 

oxygen atom by electric high voltage or UV light. Ozone is naturally produced through certain 

types of chemical reactions. The most commonly known example is the ozone layer, in which 

ozone is produced by sun’s ultraviolet rays (UV). Ozone is also formed during thunderstorms. 

In thunderstorms, ozone forms as a result of the high voltages that are involved. 

Ozone generators can create ozone artificially by means of extremely high voltages or by means 

of UV light. Both methods involve the decomposition of the oxygen molecule. This causes 

oxygen radical formation. These oxygen radicals can bind to oxygen molecules, forming 

ozone (O3). 

Ozone is one of the strongest known oxidants. It can be used to technically burn dissolved 

compounds (oxidation). The extra oxygen radical in an ozone molecule quickly binds to each 

component that comes in contact with ozone molecules. This is because of the instability of 

ozone and its inclination to return to its original form (O2). Both organic and inorganic 

substances may be oxidized by ozone, but also micro-organisms such as algae, viruses, bacteria 

and fungi. This causes the extra oxygen radical to be released from the ozone molecule and to 

bind to other materials, so that only pure and stable oxygen molecules (O2) are left. 
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As a result of the above-mentioned reaction mechanisms, ozone can be used for a large variety of 

purposes. Ozone is mainly applied in waste water and drinking water purification. 

2.3 Filters 

Prior to the actual DESMI Ocean Guard BWMS, there will normally be a mechanical filter in 

place at the Sea Chest. The purpose of the filter is to remove larger organisms and general debris. 

Two different particle filter systems can be applied at the DESMI Ocean Guard BWMS. 

The base configuration is an open pressureless filter. This filter will use screens with pore sizes 

of 20 microns. In an alternative configuration a standard pressurized filter with 

screens of 40 microns will be used instead. The ballast pump will then be installed upstream. 

The pressureless micro screen filter will provide significant filtration, which results in a much 

lower power consumption of the subsequent disinfection and also reduced accumulation of silt in 

the ballast tanks. In addition free flow filters have the advantage that the water is not forced 

through the filter as is the case with pressurized filters. This means that no soft organisms are 

pushed through the filter. This is known to occur in pressurized filters. 

Both filters remove particles so that the efficiency of the succeeding disinfection step is secured. 

It is only the incoming ballast water, which will pass the particle filters. When deballasting, the 

water bypass the particle filter and is pumped directly to the following disinfection units. 

2.4 Overview of the system 

DESMI Ocean Guard BWMS has developed a ballast water system comprising individually 

optimized modules combined in a unique combination of added treatment power and value. The 

exact combination of technologies and system design means that the combination is much more 

powerful than the individual technologies. 
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Figure 1 : Simplified flow diagram 
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2.4.1 System sizing 

It is expected that two system sizes will be designed: 300 m3/h and 1,500 m3/h. This will allow 

for combinations hereof for having modulated systems for various flow sizes. 

2.4.2 Brief description of the system 

The system consists of the following parts: 

- Filter 

- Venturi-injector system for injection of generated ozone into the ballast water flow 

- Closed reactor for having the ozone reacting with the ballast water 

- UV lamps 

As mentioned earlier, the DESMI Ocean Guard concept can be used in a configuration with 

a pressureless filter or a pressurized filter. 

The base configuration, where space is not a limiting factor, an open pressureless filter will be 

used. This filter will use screens with pore sizes of 20 microns. It will typically be installed so 

that water will flow by gravity through the filter to a combined filter housing/buffer tank from 

which the ballast pump will pump the water. This configuration is typically for the newbuilding 

market. The tests results shown here were obtained with this configuration. 

In an alternative configuration (targeting retrofits on existing vessels), a standard pressurized 

filter with screens of 40 microns will be used instead. The ballast pump will then be installed 

upstream. 

2.4.2.1 Ballast operation of pressureless filter mode 

When a ballasting process takes place the officer turns on the ballast pump and chooses the tank 

to be filled. Before the ballast pump starts the UV lamps are engaged and given 

approximately 45 seconds to warm up. The ballast pump is started and the water is pumped 

through the filter. 

The filter is self-cleaning and the material from the ballast water trapped in the filter will be 

pumped back to the sea/harbour. The cleaning process takes place during operation, meaning that 

the ballast water flow is continuous. 

From the filter the water is flowing into the closed reactor. Before entering the closed reactor the 

generated ozone has been injected through an injector. The mixture of water and ozone will be 

given a reaction period of approximately 0.5 minutes. 

The UV system is based on low pressure UV lamps. The UV lamps are prepared for the marine 

environment by having completely sealed steel end caps to avoid corrosive aerosols to reach 

electric circuits. The lamps can operate in pressure up to 4 bars. 

These lamps have an efficiency of approximately 40% in converting energy to useful UVC light. 

This is in contrast to the other dominant lamp types on the market – medium pressure lamps – 

which have an efficiency of approximately 15%. 
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The ozone pipe is under vacuum and leakage in the piping system will cause air to enter the 

ozone system and not ozone escaping. In case the vacuum will disappear, the pressure gauge will 

close the UV lamps causing the ozone production to stop. Further, the ozone meter will detect the 

lack of ozone concentration in case the level of air is increasing. 

2.4.2.2 Deballasting operation for pressureless filter mode 

When deballasting the ballast water from the ballast tanks will not pass the filter. Even though 

DESMI Ocean Guard system is removing literally all living organisms from the ballast water, 

a potential regrowth of living organisms cannot be ignored. Meaning that the ballast water is 

passing the ozone and UV step on its way out. The procedure is as described above. 

2.4.2.3 Deballasting operation for pressurized filter mode 

The pressurized concept is a more conventional concept already used in other BWMS and also 

for many other marine applications. The ballast pumps are fed from the sea crest and pumping 

the ballast water through the pressurized filter. Since a pressurized filter cannot be as fine in 

mesh as a pressureless filter, the system will require more UV radiation compared to the 

pressureless mode. 

When using the pressurized filter concept with a 40 μm mesh size, it will normally require 

a higher UV irradiation dose compared with the 20 μm open filter solution. Exactly how much 

the UV irradiation dose is going to be increased has to be investigated more carefully. The main 

parameter will be the amount of organisms having a size between 20 and 40 μm. It is expected 

that the UV irradiation dose should be increased 25%-40% compared to the open filter solution, 

i.e. having a UV irradiation dose of 210-280 mW s/m2

. 

The ballast water is pumped through the filter. Again, the pressurized filter is self-cleaning and 

does not require a stop of the ballast process during cleaning. The removed material from the 

ballast water is pumped back to the sea/harbour. 

The actual treatment process (ozone and UV) is exactly as described above for the pressureless 

mode. 

2.5 Detailed description of the system 

2.5.1 Operational overview and process description 

2.5.1.1 Brief description of the system flow: 

Two-particle filter systems will be used. If space is not a limiting factor, an open pressureless 

filter will be used. This filter will use screens with pore sizes of 20 microns. It will typically be 

installed so that water will flow by gravity through the filter to a combined filter housing/buffer 

tank from which the ballast pump will pump the water. When using a pressurized filter, screens 

of 40 microns will be used. The ballast pump will then be installed upstream. Using 20 microns 

screens is advantageous since energy consumption will be lower in the following disinfection 

steps. 
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Both filters remove particles so that the efficiency of the succeeding disinfection step is secured. 

It is only the incoming ballast water which will pass the particle filters, so that deballasted water 

is pumped directly to the following filter units. As a first step the water passes a venturi-injector. 

When water is pumped through this unit it both sucks in ozone containing air and performs 

complete mixing of air and water. The water and air mixture then enters the enhanced mass 

transfer and gas liquid separator reactor. A residence time of approximately 30 seconds allows 

the gaseous ozone to diffuse into the water phase and react with the remaining living organisms, 

while water and gas are simultaneously separated efficiently in the reactor. Due to the high 

solubility of ozone, the gas will have zero or a very low-ozone concentration. However, for 

safety reasons the off-gas will pass an ozone destructor before exhaust to the atmosphere. 

Ultimately, water flows to the combined UV-sterilizer/ozone generator as the last step in the 

treatment process. A high dose of UV radiation from undoped low pressure UV lamps is used 

for three purposes: 

.1 killing of living organisms; 

.2 radical formation, by residual dissolved ozone photolys; and 

.3 generation of gaseous ozone by radiation of atmospheric air. 

The vacuum created by the venture-injector sucks atmospheric air through the ozone generating 

components via a pipeline to the injector for mixing with the water. Finally, purified water is 

directed to the ballast tanks or during deballasting to the recipient water. 
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2.5.1.2 General flow diagram 

Figure 2 : System flow diagram 
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2.5.2 Major components 

2.5.2.1 Pressureless filter (Disc filter) 

Instead of the typical 50 microns pre-filter, the DESMI Ocean Guard BWMS filters down 

to 20 microns. This is realized with large area open filter technology (Disc filter). The capacity of 

the Disc filter can be upscaled by adding identical filter segments making the filter longer and/or 

wider. By means of gravity backflush, water leaves the filter and is pumped to disposal via 

separate piping. 

The Disc filter is a mechanical and self-cleaning filter that offers a large filter area with 

a relatively small footprint, especially compared with the fineness of the filter. The filter design 

is superior in removal of solids and organisms due to the very low mesh size compared to 

conventional pressurized filters. 

The water to be treated flows by gravity into the filter segments from the centre drum. Solids 

catch on the inside of the filter panels mounted on the two sides of the disc segments. As the 

solids catch on the inside of the filter media impeding the flow of water through the disc, the 

water level inside the discs begin to rise, triggering a level sensor to start the disc to rotate and 

a backwash cycle begins. 

High-pressure rinse water backs the solids off the filter media and into the solids collection 

trough. Typically the backwash requires 0.05%-3% of the total flow. Filtered water is used for 

backwash. 

2.5.2.2 Pressurized filter 

The pressurized filter is a mechanical self-cleaning mesh filter. The filter segments are built up in 

a cylindrical form with separate filter mesh rods. 

The filter is self-cleaning and operated by either pressure measurement or time. The filter rods 

are cleaned successively and allowing the filter to be in operation during cleaning mode. 

Pressurized water is backflushing the filter mesh and the contaminated cleaning water is guided 

to the sea/harbour. 

In filtration mode the ballast water is pumped to the filter elements. All particles larger 

than 40 microns are removed and retained on the external surface of the screens. The filtered 

water leaves via the outlet connection. When the differential pressure between the dirty and clean 

sides of the filter increases to approximately 0.5 bar, this will be registered by a differential 

pressure transmitter and the control unit will start a backflushing cycle. Compressed air drives 

a small volume of clean liquid through the filter element in reverse direction and blasts the 

entrained contaminants from the surface of the filter elements and out of the filter chamber. The 

backflushing process is performed sequentially on each filter element, so that the flow of filtered 

ballast water is not significantly interrupted. 

2.5.2.3 Venturi-injector 

When a pressurized operating (motive) fluid enters the injector inlet, it is constricted towards the 

injection chamber and changes into a high-velocity jet stream. The increase in velocity through 

the injection chamber results in a decrease in pressure, thereby enabling an additive material to 
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be drawn through the suction port and entrained into the water. As the jet stream is diffused 

toward the injector outlet, its velocity is reduced and it is reconverted into pressure energy (but at 

a pressure lower than injector inlet pressure). The selected injector design is extremely efficient. 

It operates over a wide range of pressures and requires only a minimal pressure differential 

between inlet and outlet sides to initiate a vacuum at the suction for the ozone containing gas. 

The air to water ratio in this application is approximately 5% on a volumetric basis. 

A side-effect of the extreme changes in the hydraulic conditions through the injector is that 

especially organic particles will be broken down into smaller particles which are more sensitive 

to both UV radiation and ozonation. 

2.5.2.4 Ozone reactor and air/water separator 

The integration of the following two important elements of an ozone system is ideal: Reactor 

volume giving the ozone time to react with the constituents of the water and efficient separation 

of gas and water. The general design principle is counter flow where air bubbles rise to the top 

and evacuate through an air vent and water flows in a circular movement to the bottom and out. 

Residence time is 30-120 s. The reactor is hydraulically optimized using CFD-modeling in order 

to obtain even retention times and effective gas/water separation. Performance of the reactor is 

continuously controlled using inputs from level meters, water and gas flow meters. 

2.5.2.5 Ozone gas destructor 

The ozone destructor is placed at the ozone reactor – air/water separator for avoiding ozone being 

released into the atmosphere. The ozone destructor is filled with a catalytic destruction material. 

It will convert the ozone into harmless oxygen in milliseconds. The filling material acts 

catalytically and there are no toxic gases emitted such as carbon monoxide and carbon dioxide. 

The exhaust air will exit through a piping system. An ozone gas sensor will check the efficiency 

of the destructor. 

2.5.2.6 UV lamps, UV sterilizer – Gaseous ozone generator 

The UV system is based on low pressure UV lamps. The UV lamps are prepared for the marine 

environment by having completely sealed steel endcaps to avoid corrosive aerosols to reach 

electric circuits. The lamps can operate in pressure up to 4 bars. 

The system is delivered with a visual lamps failure alarm for each lamp, ensuring continued 

operation even if a lamp needs to be excluded due to failure. Further, each lamp has an elapsed 

time meter making traceability of lamp operation simple. Cabinet material will be Stainless Steel 

AISI 316, seawater resistant. 

During operation quartz sleeves are continuously wash wiped physically to ensure optimum 

transparency between lamp and ballast water to be treated. 

UV reactor temperature is constantly monitored to ensure shutdown of reactor in case of water 

flow failure or air present in the reactor. The temperature surveillance is last safety barrier, and 

will disable the ballast system until serviced. 

These lamps have an efficiency of approximately 40% in converting energy to useful UVC light. 

This is in contrast to the other dominant lamp types on the market – medium pressure lamps – 

which have an efficiency of approximately 15%. 
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2.5.2.7 TRO sensor 

When ozone reacts with the ballast water, oxidizing agents are produced. Persistent oxidants 

produced during ozonation are collectively referred to as the total residual oxidants (TRO). 

Typical persistent oxidants include bromine (Br-

), bromite (OBr-), bromate (BrO3

-

), and 

hypobromous acid (HOBr). These oxidizing agents are essential for the treatment process. 

TRO sensors will continuously provide real-time control of the ozonation process and 

confirmation that discharge levels are not exceeded. 

2.5.2.8 Ambient Ozone Gas Sensor 

The ambient ozone detection system consists of individual modules that will be located in all 

relevant areas. The selected sensor transmitters are constructed with automatic sensor testing 

systems, which will reduce the operators testing requirements. Receiver modules contain 

electronics for the detection and alarm systems. Each module includes a digital display of gas 

concentration, and a 4-20 mA signal to central PLC. The sensor and module will, in addition to 

the ships power supply, also be powered by a battery power supply. The power supply provides 

a power failure relay and charging for the battery back-up unit. The receiver modules will be 

linked directly to visual alarms and audible horns, also powered by both battery and shipboard 

power supply. 

2.5.2.9 Programmable logic controller (PLC) panel 

The treatment system is fully automated and completely self-contained with PLC control and 

with informative touch panels. The monitoring and control include flow meters, pressure 

transmitters, water quality and ozone gas sensors, automatic valves, etc. 

All relevant process parameters, events and alarms will be logged and can be read directly on the 

panel or transferred using USB ports or net. Depending on the grade of automation of the 

existing ballast water system, typically the treatment system will require no additional actions by 

the crew or alterations of current ballast water procedures. The system is equipped with all 

necessary emergency shut-off devices. 

2.5.3 System requirements, monitoring and control, crew interaction 

2.5.3.1 Requirements 

The treatment system is designed as a modular system. In order to reduce space requirements, all 

units can be installed independently. 

Space requirement is as follows: 

2 * 300 m3

/h ballast water flow: 7/15 m2 (40 microns filter/20 micros filter) 

1500 m3/h ballast water flow: 12/35 m2 (40 microns filter/20 microns filter) 
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Power requirement is as follows: 

2 * 300 m3

/h ballast water flow: 40/25 kWh (40 microns filter/20 microns filter) 

1500 m3/h ballast water flow: 135/85 kWh (40 microns filter/20 microns filter) 

Waste water flow from filter flushing is typically less than 2% of the ballast water flow. The 

waste contains no added substances and will be returned to the sea. 

2.5.3.2 Personnel requirements 

The ballast water treatment system will only need a minimum of input from the crew. The crew 

members perform ballasting and deballasting as normal. 

Maintenance and control operations are very easy and the necessary instructions will be 

provided. 

2.5.3.3 Maintenance requirements 

The UV-lamps need to be replaced for every 12,000 H operating hours. Some control 

components (e.g., pH and ozone sensors) also need to be changed regularly. The PLC control 

system will inform about the necessary maintenance operations. Confirmation from the operator 

of performed maintenance work is required by the PLC.

A maintenance and test schedule will be provided. 

2.5.3.4 Handling of waste and replaced parts of the system 

During the treatment process, no liquids or solid wastes are produced. Replaced lamps should be 

handed in to DESMI Ocean Guard for recycling. In case of damaged UV lamps, it is important to 

note that the lamp mercury is contained in the small (<1 cm2

) amalgam spot on the inner glass 

tube. Broken lamp glass should therefore be disposed of according to local regulations or sent to 

DESMI Ocean Guard. 

2.5.3.5 Handling, use, storage and transport of the chemicals 

As ozone, the Active Substance is produced by the Ozone Generator Module installed on board a 

vessel, there is no need to transport, load and store either the Active Substance or other chemicals 

on board. 

2.5.3.6 Cleaning requirements 

LPUV lamps have a low surface temperature and the normal cleaning practice is to use a wiper 

for cleaning the lamps, i.e. a mechanical cleaning contrary to the chemical cleaning normally 

required with MPUV. 

With regard to the organisms being able to survive in the BWMS piping between the operations 

of the system it is the intention to carry out a flushing procedure where organisms potentially 

surviving in the piping system will be flushed into a ballast tank and pass the ozone/UV 

treatment step before being discharged. 
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2.5.4 System locations 

The DESMI Ocean Guard BWMS can be located in any suitable and convenient location 

depending on the ship’s design. The naval architects and marine engineers of 

DESMI Ocean Guard will consider and discuss with the client to keep engineering for the 

integration of the BWMS at a low level, to not interfere with normal cargo operations and 

required crew activities, and to look for placement opportunities next to the ballast water pumps 

to minimize the piping length. 

2.6 Operational safety features and alarms 

All system components will be of maritime standard type and will have the appropriate approval 

of the classification society and/or relevant regulatory authority. 

Water pressure will not exceed 1 bar unless for very small flows during flushing of filters. 

It will not be possible to access moving parts or UV lamps during operation. The system will 

automatically shut off if protective housings, etc., are opened. 

The ozone containing air is driven by a vacuum generated by the venture-injector. Leaks in the 

gas pipeline will therefore result in atmospheric air intrusions into the pipeline and not ozone 

leaks to the surroundings. Leaks in the ozone pipeline will be registered by either the vacuum 

transmitter or by the dissolved ozone sensor. 

Using a vacuum transmitter, the system will only allow air flow to the ozone generating 

compartments when the vacuum is registered. 

Off gas from the ozone reactor may contain small concentrations of ozone. The off gas will go 

directly to the ozone gas destructor. An ozone sensor will continuously check the effectiveness of 

the destructor. The de-ozonated off gas will be vented to the outside via a pipeline. In the 

unlikely event that ozone escapes to the ambient surroundings, ozone sensor receivers will start 

an alarm procedure. 

Emergency shut-off devices will be installed at the water treatment units and at the engine 

control room. 

2.7 Procedures and management measures 

The operation of the DESMI Ocean Guard ballast water treatment system will be integrated into 

the Ship Safety Manual (SMS) as an integral part of the ISM2 documentation. 

Therefore, procedures have to be made based on the service and maintenance routines described 

in the system documentation. 

Proper engineering during installation, thorough testing, training of the personnel and adequate 

maintenance will prevent emergency situations and secure safe operation of the ballast water 

management system. 
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2.8 Evaluation of management measures

Preventing exposures and emergency situations starts with proper engineering and installation of 

the DESMI Ocean Guard BWMS on board the ship. The management measures discussed above 

consider location, training and handling of the plant. In connection with the risk assessment, 

these measures are considered to be adequate to avoid uncontrolled or emergency situations and 

to operate the ballast water management system in a safe manner. 

2.9 Performance test 

DESMI Ocean Guard BWMS has undergone a pilot-scale performance test at Danish Hydraulic 

Institute (DHI), Denmark, in April 2009. The full report is enclosed in confidential material of 

this application. 

Viable organisms > 50 μm were enumerated and determined for viability by microscopy after 

reverse filtration with a 50 μm filter. Only organisms above 175 μm were counted. Organisms 

between 50 μm and 175 μm were not quantified. These organisms were mainly ciliates. They 

appeared, by visual judgment, to be reduced to the same extent as those larger than 175 μm. 

Viable organisms below 50 μm were determined as algae by three methods: Fluorescence 

microscopy (determines number of algae with chlorophyll), Chlorophyll (an estimate of the algae 

biomass) was determined by chemical analysis (HPLC), and primary production (determines the 

activity, i.e. the living algae). Heterotrophic bacteria (a general measurement of the number of 

bacteria) were determined as plate count on yeast extract after ISO 6222. 

The samples on day 0 were stored at 15°C and analysed approximately 12 hours after sampling. 

Separate samples for the determination of heterotrophic plate count were stored at 4°C and 

analysed approximately 12 hours after sampling. 

The overall conclusion of the performance test was: 

- The results of the investigations show that the BWMS removes the living algae 

to 1% at day 0 and less that 0.01% at day 5, which is in compliance with the 

requirements of the Ballast Water Management (BWM) Convention. The filter allows 

some of the algae to pass the treatment but they are not in a viable state. 

The reduction of the heterotrophic plate count shows a reduction to between 0.03% and 2%, 

which is believed to be sufficient to remove any bacterial contamination to a level that complies 

with the IMO requirements. 

Cells above 50 μm are removed to 0.1% which is a factor of 10 above the IMO requirement. The 

cause of this was detected to be a sub-optimum construction of the filter. During backflushing of 

the filter, it was possible for smaller parts of the water containing parts from the dirty side of the 

filter to get in contact with the filtered water. This observation was discussed with the filter 

experts and it is believed that an optimization of the filtration unit is possible. The filters used for 

larger-scale tests will not have this possibility for mixing filtered water with contaminated water. 
MEPC 60/2/4 

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2.10 System advantages: 

- Filtration down to 20 microns drastically lower sludge problems in ballast tanks. 

- Filtration down to 20 microns lower needed power consumption in disinfection step. 

- Filtration down to 20 microns means that a major part of micro life, including the 

main algae biomass, is filtered out before the disinfection steps. 

- The double disinfection strategy with both ozone and UV ensures best possible 

quality of ballast water no matter how coloured or how high turbidity is in the feed 

water. 

- The application of low-pressure radiation and ozone in an advanced oxidation process 

generates short-lived radicals boosting disinfection power. The exactly dimensioned 

low-pressure UV step ensures that no ozone or radicals of ozone are left after the 

treatment process ensuring safe deballasting and protection of ballast tank coating. 

- The analysis of treated water indicated that the application of low-pressure UV and 

ozone has not generated harmful chemicals during the treatment process. 

3 DATA-SET FOR ACTIVE SUBSTANCES AND PREPARATIONS 

3.1 Chemical identification 

Based on the definitions of “Preparations”, “Active Substances”, “Relevant Chemicals” and 

“Other components”, as outlined in the revised Methodology for information gathering and the 

conduct of work of the GESAMP-BWWG (MEPC 58/2/7, annex 4), substances used or 

generated by the DESMI Ocean guard BWMS are classified as follows: 

Preparation means any commercial formulation containing one or more Active 

Substances including any additives. 

The DESMI Ocean Guard BWMS does not use any commercial Preparations. 

Active Substance means a substance or organism, including a virus or a fungus that has 

a general or specific action on or against harmful aquatic micro-organisms and pathogens. 

The DESMI Ocean Guard BWMS produces ozone generated on site. 

The photon is responsible for the inactivation of harmful aquatic micro-organisms and 

pathogens present in ballast water together with ozone and ozone radicals formed during 

decomposition of ozone in the AOP process. The main radical is short-lived hydroxyl 

ions with half-lives in the order of microseconds to milliseconds. As a result, chemicals 

are not required stored on board but generated on demand. 
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Relevant Chemicals means transformation or reaction products that are produced during 

and after employment of the ballast water management system in the ballast water or in 

the receiving environment and that may be of concern to the ship’s safety, aquatic 

environment and/or human health. 

Relevant Chemicals are OH▪ radicals and a range of possible by-products are considered 

other substances.

3.2 Background to characterize reactive physical processes, relevant and 

other chemicals 

3.2.1 Reactive physical processes 

3.2.1.1 The photon 

According to the wave/particle-duality light can be considered as energy propagating as a wave 

and as a stream of photons with the constant speed of light. A photon is defined as a quantum of 

electromagnetic energy at a given frequency. Consequently, a photon possesses the more energy 

the shorter the wavelength. The energy characteristic for a photon at a specific wavelength is 

determined as: 

E = hc/λ 

Where E is energy in Joule, h is the Planck constant, c is the speed of light and λ is the 

wavelength in meters. 

Ultraviolet light (UV) is part of natural sunlight. Electromagnetic wavelength spectrum of UV 

(UV spectrum) is 100-400 nm bordered by x-ray radiation (<100 nm) and visible light 

(400-700 nm). According to the draft of ISO standard on determining solar irradiances 

(ISO-DIS-21348), the UV spectrum is subdivided into UV-A (long wave, 315-400 nm), UV-B 

(medium wave, 280-315 nm), UV-C (100-280 nm) and vacuum UV (10-200 nm). 

UV-C can be used as a disinfectant against micro-organisms and pathogens including bacteria, 

viruses and phages (Hijnen et al. 2006). Therefore, UV-C is also referred to as germicidal light. 

Germicidal light is successfully applied in portable and waste water management and the 

disinfection of water in aquaculture (Oppenländer 2003). The applicability of UV in the 

treatment of ballast water of ships has been tested successfully in the laboratory and on the large 

scale (Welschmeyer et al. 2004). 

The basic process of disinfection with UV light is photolysis. Photolysis is the decomposition of 

a molecule by light. The strength of the chemical bond determines the photonic energy necessary 

for cleavage. Photonic energy of UV-C ranges from 4.43 to 12.40 eV. A photon of UV254 nm 

contains 4.89 eV photonic energy. 

For water disinfection two different UV techniques are widely used differing in their 

UV emission spectra. Middle Pressure UV (MPUV) lamps emit light over a broad range of UV 

and visible light. Low-pressure UV (LPUV) lamps emit monochromatic light at the specific 

wavelength of 254 nm (UV254nm) to specifically take advantage of the DNA damaging effect, 

and reduce the formation of potential by-products. 
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Absorption time for a photon by a molecule is in the range of nano- to picoseconds. It is 

generally accepted that photons leave no residuals in water. Accordingly, the use of UV for water 

disinfection and treatment (including ballast water treatment) is considered a purely physical 

process producing negligible amounts of by-products (DVGW 2001, USEPA 2006, 

Umweltbundesamt 2008). 

Parts of the content for this explanatory section were taken from the published and approved 

application “Harmful Aquatic Organisms In Ballast Water” from Germany [9]. 

3.2.1.2 Ozone 

When ozone is produced, it will decay rapidly, because ozone is an unstable compound with 

a relatively short half-life. The half-life of ozone in water is a lot shorter than in air (see Table 1). 

Ozone decays in water under drinking water conditions (pH: 6-8.5), partly in reactive 

OH-radicals. Therefore, the assessment of an ozone process always involves the reactions of 

two species: ozone and OH-radicals. When these OH-radicals dominate in the solution, it is 

called an advanced oxidation process (AOP). The decay of ozone in OH-radicals in natural 

waters is characterized by a fast initial decrease of ozone, followed by a second phase in which 

ozone decreases by first order kinetics [19]. Dependent on the quality of the water, the half-life of 

ozone is in the range of seconds to hours. Factors influencing the decomposition of ozone in 

water are temperature, pH, environment, concentrations of dissolved matter and UV light. 

The main factors for ozone decomposition are: 

• temperature 

• ultraviolet light 

• pH 

• dissolved solids 

• carbonate and bicarbonate 

• natural organic matter 

Temperature: Temperature has an important influence on the half-life of ozone. Table 1 shows 

the half-life of ozone in air and water. In water, the half-life of ozone is much shorter than in air, 

in other words ozone decomposes faster in water [19]. 

The solubility of ozone decreases at higher temperatures and is less stable. On the other hand, the 

reaction speed increases with a factor 2 or 3 per 10°C [19]. Principally, ozone dissolved in water 

cannot be applied when temperatures are above 40°C, because at this temperature the half-life of 

ozone is very short. 

For the DESMI Ocean Guard BWMS the half-life issue is not so relevant. First of all the sea 

water temperature can never exceed 34°C. Secondly, the reactor chamber used for ensuring the 

generated ozone to come in proper contact with the ballast water has a size allowing the ozone to 

react within a period of 30-120 seconds. 
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Dissolved in water (pH 7) 

Table 1 : Half-life of ozone in gas and water at different temperatures

Temp (°C) Half-life

15 30 min 

20 20 min 

25 15 min 

30 12 min 

35 8 min 

Using UV to remove ozone has an advantage because UV does not require additives that may 

leave behind residuals. In addition, dissociation of ozone with UV also helps to oxidize Total 

Organic Compounds (TOCs) and disinfect. 

Germicidal ultraviolet light destroys ozone in water very quickly. The 254 nm wavelength 

produced by low-pressure germicidal UV lamps is quite effective. The mechanism for removing 

ozone is dissociation, which occurs when 254 nm UV energy “breaks” one of the oxygen bonds 

in an ozone molecule. As a result of this reaction, each ozone molecule is converted into one 

oxygen atom and one oxygen molecule. Free oxygen atoms will combine with each other to form 

oxygen molecules. 

Although ozone is readily destroyed by UV, it requires more UV energy than inactivation of 

micro-organisms (approximately 90 mJ/cm2

 versus 30 mJ/cm2). Therefore, in order to ensure 

effective ozone destruction, UV systems are often sized using a “flow-rate adjustment” of 40% 

the flow-rate of a disinfection system. 

Research by Summerfelt from 2003 [10] gives a more detailed view of destruction from practical 

experiments. Recirculated aquaculture water flow was adjusted to 85, 170, 255, and 330 L/min 

(i.e. approximately so as to produce a range of different water retention times within the 

UV irradiation unit (i.e. 6.7, 3.3, 2.2, and 1.7 s, respectively) and thus produced UV irradiation 

doses of 153.3 ± 2.1 mW s/cm2, 80.4 ± 2.6 mW s/ cm2, 49.3 ± 0.6 mW s/cm2, 

and 35.6 ± 0.3 mW s/cm2, respectively. The results show that dissolved Ozone Molecule (O3) 

removal across the UV irradiation unit could be modeled using first order kinetics and was 

dependent upon the inlet O3 concentration and the retention time within the irradiation chamber. 

At a temperature of 13-15°C, UV irradiation doses of 80.4 ± 2.6 mW s/cm2

 and 153.3 ± 2.1 

mW s/cm2

 consistently removed 100% of the dissolved O3 when the inlet O3 concentration 

was <0.30 mg/L. Note that the DESMI Ocean Guard BWMS delivers 150-200 mJ/cm2

 and the 

ozone concentration is <0.3 mg/L. A UV irradiation dose of 49.3 ± 0.6 mW s/cm2

 consistently 
MEPC 60/2/4 

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removed 100% of the dissolved O3 when the inlet O3 concentration was <0.10 mg/L. The DESMI 

Ocean Guard BWMS is intended to operate within a UV irradiation dose 

of 150-200 mW s/cm2

 and 0.25 mg/L ozone concentration meaning that even in waters of high 

turbidity and low organic content no ozone should pass the UV radiation step. However, the risk 

of ozone passing into the ballast tanks and potentially leading to exposure of humans through the 

ventilation system is going to be checked during the full-scale tests. 

Ozone decomposes partly into OH-radicals. When the pH value increases, the formation 

of OH-radicals increases. In a solution with a high pH value, there are more hydroxide ions 

present, see formulas below. These hydroxide ions act as an initiator for the decay of ozone: 

1 O3 + OH- → HO2

-

 + O2 

2 O3 + HO2- → •

OH + O2 •- + O2 

The radicals that are produced during reaction 2 can introduce other reactions with ozone, 

causing more OH-radicals to be formed. In addition, the pH influences acid/base equilibriums of 

some compounds and also the reaction speed of ozone. This applies also to the reaction with 

scavenger CO3

2-, which is also pH dependent (Pka HCO32-/CO32- = 10.3). 

Dissolved ozone can react with a variety of matter, such as organic compounds, viruses, bacteria, 

etc. As a result, ozone decomposes to other matter. For example, the half-life of ozone in distilled 

water is much shorter compared to tap water. Ozone decomposes in water in OH-radicals. 

Dependent on the nature of the dissolved matter, these can accelerate (chain reaction) or slow 

down the decay of ozone. Substances that accelerate this reaction are called promoters. Inhibitors 

are substances that slow down the reaction. When water is ozonized, one often uses the term 

“scavenging capacity”. Scavengers are entities that react with OH-radicals and slow down the 

chain-reaction. The scavenging capacity can be defined as follows: 

kOH-DOC[DOC] + kOH-HCO3-[HCO3

-

] + kOH-CO32-[CO3

2-] 

[19] 

Scavengers slow down the chain-reaction. This is because after the reaction of scavengers 

with OH-radicals, the reaction products do not react with ozone any further. Carbonate is 

a scavenger with a strong effect. The addition of carbonate (CO3

2-) can increase the half-life of 

ozone [19]. The effect on the reaction speed is highest at low concentrations. Above 2 mmol-1 for 

ozonization and 3 mmol l-1 for advanced oxidation process (AOP), the decrease in the reaction 

speed is negligible [19]. When a solution mainly undergoes indirect reactions (with OH-radicals), 

for instance in a solution with a high pH value or an AOP-process, the presence of scavengers is 

undesired. The scavengers react very fast with OH-radicals and lower the oxidation 

capacity. For this kind of processes a low scavenging capacity is required. Carbonate 

(CO3

2-) ions are much stronger scavengers than bicarbonate (HCO32-) ions 

(reaction speed CO3

2-: k = 4,2 * 108

 M-1s

-1 and reaction speed HCO3-

: k = 1.5 * 107 M-1s

-1). 

That is why in an ozone process under drinking water conditions the bicarbonate concentration is 

less important [19]. 
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Natural organic matter: Natural organic material (NOM) exists in every kind of natural water 

and is often measured as dissolved organic carbon (DOC). NOM reduces the quality of the water 

with regard to colour and odour. Ozone can be used in water treatment, for the reduction of the 

concentration of NOM. The concentration of NOM in natural waters can vary 

from 0.2-10 mg l-1 [19]. The influence of NOM on ozone is twofold. Depending on the type 

of NOM, it can be oxidized directly by ozone. This is the case for compounds which easily react 

with ozone, such as double bonds, activated aromatic compounds, de-protonated amines and 

sulphide [19]. On the other hand, OH-radicals can react with NOM (indirect reaction) and act as 

a promoter or as a scavenger. In natural waters, it is difficult to determine the stability of ozone 

as a result of the indefinite effect of NOM. That means it is not possible to estimate the fraction 

that accelerates or slows down the reaction [19]. 

3.2.1.3 Advanced Oxidation Process (AOP) 

Oxidation is defined as the transfer of one or more electrons from an electron donor (reductant) 

to an electron acceptor (oxidant), which has a higher affinity for electrons. These electron 

transfers result in the chemical transformation of both the oxidant and the reductant, in some 

cases producing chemical species with an odd number of valence electrons. These species, 

known as radicals, tend to be highly unstable and, therefore, highly reactive because one of their 

electrons is unpaired. Oxidation reactions that produce radicals tend to be followed by additional 

oxidation reactions between the radical oxidants and other reactants (both organic and inorganic) 

until thermodynamically stable oxidation products are formed. The ability of an oxidant to 

initiate chemical reactions is measured in terms of its oxidation potential. The most powerful 

oxidants are fluorine, hydroxyl radicals (•OH), ozone and chlorine with oxidation potentials 

of 2.85, 2.70, 2.07 and 1.49 electron volts, respectively [1].

AOPs involve the two stages of oxidation discussed above: 1) the formation of strong oxidants 

(e.g., hydroxyl radicals); and 2) the reaction of these oxidants with organic contaminants in 

water. However, the term “advanced oxidation processes” refers specifically to processes in 

which oxidation of organic contaminants occurs primarily through reactions with hydroxyl 

radicals [2].

In water treatment applications, AOPs usually refer to a specific subset of processes that 

involve O3, H2O2, and/or UV light. These processes can produce hydroxyl radicals, which can 

react with and destroy a wide range of organic contaminants, including marine organic microlife. 

In general, the effectiveness of an AOP is proportional to its ability to generate hydroxyl radicals. 

As with the other treatment technologies, the design of an AOP is governed by the influent 

contaminant concentration, target effluent contaminant concentration, desired flow rate and 

background water quality parameters such as pH, bromide concentration and alkalinity. The key 

design parameters for AOPs include: chemical dosages and ratios with other chemicals, reactor 

contact time and reactor configuration. The optimum dosages, ratios and contact time are 

water-specific and treatment scenario-specific. As can be expected, higher chemical dosages and 

contact times are typically expected to result in higher removal rates. 

There are many water quality parameters that may impact the disinfection effectiveness of any 

particular AOP. For example, nearly all dissolved organic compounds present in the source water 

will serve to reduce the disinfection efficiency by consuming •OH. Below is a brief discussion of 

the importance of these water quality parameters and the mitigation measures that can be taken to 

limit the detrimental impact of these parameters on AOP disinfection effectiveness. 
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Alkalinity. The detrimental impact of alkalinity on the effectiveness of AOPs has been 

extensively studied [14]. As mentioned previously, the hydroxyl radical is non-selective and, 

thus, can be exhausted by the presence of organic or inorganic compounds other than the 

organisms of concern. Both carbonate and bicarbonate will scavenge hydroxyl radicals to create 

carbonate radicals which, in turn, react with other organic or inorganic compounds present, albeit 

at a much slower rate, [3], [14]. The reaction for the scavenging of hydroxyl radicals by 

bicarbonate ions is shown below [4]: 

•OH + HCO3 - Æ CO3• + H2O 

The rate constants, k, for the reactions of the hydroxyl radical with carbonate and bicarbonate 

are 3.8 x 108 and 8.5 x 106 M-1s-1, respectively [17].

However, for these second order reactions, the actual reaction rate, r, is a function of both the rate 

constant and the concentration of the reactant, C: r = k [C]. 

TOC and NOM. TOC measurement incorporates all organic compounds present in the water, 

both dissolved organic carbon (DOC) and particulate organic carbon (POC). Particulate organic 

carbon can be both living and dead organisms. NOM, a subset of TOC, is commonly used to 

describe large macromolecular organic compounds present in water. These macromolecules can 

include humic substances, proteins, lipids, carbohydrates, fecal pellets, or biological debris [5], 

and, while not highly reactive, often contain reactive functional groups [6] .

The rate constants reported in the literature for hydroxyl radical reactions with NOM range from 

1.9 x 104 to 1.3 x 105 (mg/L)-1s-1 , [14]. 

Turbidity. Systems relying on UV irradiation for the dissociation of O3 exhibit a decrease in 

efficiency as turbidity increases. Turbidity lowers the transmittance of the source water and, thus, 

lowers the penetration of the UV radiation into the source water. 

3.2.1.4 Bromate Formation 

In addition to organic oxidation by-products, inorganic by-products can also be formed. Bromide 

concentrations can range from non-detect to several hundred μg/L in raw drinking water and 

reach several mg/L in brackish water, [6]. During the use of AOPs that employ ozone, bromate 

can be formed when bromide is present in the source water ([11], [16], [12]). The conversion of 

bromide to bromated can proceed as follows ([11], [12]): 

Br- → BrO- → BrO2- → BrO3-Br- → Br• → BrO• → BrO2- → BrO2• → BrO3- 

Due to the low-ozone concentration in the system bromated formation is not expected to be of 

concern but this will be investigated and documented in the process towards Final Approval. 
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3.3 Advantages and considerations when using the O3/UV system 

The benefits of using the O3/UV system are: 

• The removal efficiency of the combined O3/UV process is typically higher than the 

additive removal efficiencies of ozone and UV alone, [7]. The magnitude of this 

synergistic effect varies depending on the contaminant of interest, [7].

• Ozone can be completely decomposed in the process ensuring treated water without 

oxidation potential or content of harmful ozone. 

The considerations to be taken into account of the O3/UV system are: 

• The use of ozone for source waters with high bromide concentrations (>0.1 mg/L) can 

result in the formation of bromate. 

• The O3/UV process typically requires an off-gas treatment system for ozone 

destruction. 

• Gaseous O3 must be diffused into the source water, resulting in potential mass transfer 

limitations [13].

• UV light penetration into the source water – and, thus, process efficiency – can be 

adversely affected by turbidity [7]. 

• There are many interference compounds that absorb UV light (e.g., nitrate and iron) 

and, thus, reduce process efficiency. 

4 RISK ASSESSMENT 

The section below is an extract from the executive summary of “Preliminary chemical 

characterization, whole effluent toxicity and risk evaluation of treated ballast water for basic 

approval application” from DHI. The full report is enclosed in confidential material of this 

application. 

The overall aim of the evaluation was to establish a preliminary overview of the fate and effect of 

Active Substances and formed by-products in the environment as well as performing 

a preliminary risk assessment in relation to both human health and environment. The evaluation 

is to be used in relation with a Basic Approval application. 

The following main topics are evaluated: 

.1 Chemical characterization of treated ballast water. 

.2 Whole effluent aquatic eco-toxicity test. 

.3 Theoretical fate and effect evaluation. 

.4 Estimation of discharged and environmental concentrations of Active Substances 

and potential by-products (PEC) by use of MAM-PEC modelling. 
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.5 An environmental risk assessment. 

.6 A human exposure scenario and risk assessment for crew and public. 

4.1 Chemical characterization of treated ballast water 

The water samples were collected by personnel from DESMI Ocean Guard A/S in acid-rinsed 

heat-treated glass bottles delivered by Teknologisk Institut, Århus, Denmark. The samples were 

collected on 2 July 2009 from a lake at Aalborg University (freshwater) and Aalborg 

harbour (marine water), respectively. Sampling locations were chosen by personnel 

from Ocean Guard A/S. 

Immediately before sampling, the water was treated by DESMI Ocean Guard A/S ballast water 

treatment facility. On 2 July 2009, the samples were forwarded to Teknologisk Institut, Århus by 

courier. The samples were characterized by the following parameters: 

Table 2 : Chemical characterization of treated and untreated fresh and 

marine water at sampling 

Freshwater Marine water 

Parameter Untreated Treated Untreated Treated 

Oxygen (%) 98 100 107 112 

pH 7.8 7.7 8.0 7.9 

Temperature (°C) 22.1 21.6 23.9 23.1 

Conductivity (μS/cm) 636 635 37200 37000 

Salinity (‰) 0.1 0.1 23.6 23.6 

Ozone (mg/L)* 0 0 0 0 

* Detection limit 0.01 mg/L 

The detection limits for the respective analysis are shown as < value in Table 2. 
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The results of the chemical analyses are depicted in Table 3. 

Table 3 : Chemical characterization of treated and untreated fresh 

and marine water 

CAS No. Parameter Freshwater 

before 

treatment 

Freshwater 

after 

treatment 

Marine water 

before 

treatment 

Marine water 

after 

treatment 

Sum parameters and 

nitrite (mg/L) 

7632-00-0 Nitrite (NO2), mg/L 0.28 0.33 <0.005 <0.005

NA AOX, mg/L 0.05 0.04 0.17 <0.01

NA EOX, mg/L < 0.001 < 0.001 < 0.001 < 0.001

NA Oxidizing substances (e.g. 

Cl2,H2O2,O3), mg Cl2/l < 0.04 < 0.04 0.35 < 0.04

NA VOC, mg/L 0.09 0.1 0.04 0.03

NA NVOC, mg/L 15 15 3.3 3.3

NA Suspended matter, mg/L 5.2 3.1 4.8 3.3

Trihalomethanes 

(THM) 

67-66-3 

Trichloromethane Cl3CH 

(chloroform) < 0.05 < 0.06 < 0.07 < 0.08

75-25-2 

Tribromomethane Br3CH 

(bromoform) < 0.02 < 0.02 < 0.02 < 0.02

124-48-1 

Dibromochloromethane 

CHClBr2 < 0.02 < 0.02 < 0.02 < 0.02

75-27-4 

Dichlorobromomethane 

CHBrCl2 < 0.02 < 0.02 < 0.02 < 0.02

Highly volatile 

halogenated 

hydrocarbons (LHKW) 

106-93-4 1,2-dibromoethane < 0.02 < 0.02 < 0.02 < 0.02

96-18-4 1,2,3-trichloropropane < 0.02 < 0.02 < 0.02 < 0.02

95-49-8 2-chlorotoluene < 0.02 < 0.02 < 0.02 < 0.02

106-43-4 4-chlorotoluene < 0.02 < 0.02 < 0.02 < 0.02

96-12-8 

1,2-dibromo-3-

chloropropane < 0.02 < 0.02 < 0.02 < 0.02

608-21-9 1,2,3-tribromobenzene < 0.05 < 0.05 < 0.05 < 0.05

71-55-6 1,1,1-Trichloroethane < 0.02 < 0.02 < 0.02 < 0.02

56-23-5 Carbon tetrachloride < 0.02 < 0.02 < 0.02 < 0.02

79-34-5 Tetrachlorethene < 0.02 < 0.02 < 0.02 < 0.02

Haloacetic Acids (HAA) 

(μg/L) 

79-11-8 

Monochloroacetic acid 

(MCAA) < 1.0 < 1.0 < 1.0 < 1.0

79-43-6 

Dichloroacetic acid 

(DCAA) < 1.0 < 1.0 < 1.0 < 1.0

76-03-9 

Trichloroacetic acid 

(TCAA) < 1.0 < 1.0 < 1.0 < 1.0
MEPC 60/2/4 

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CAS No. Parameter Freshwater 

before 

treatment 

Freshwater 

after 

treatment 

Marine water 

before 

treatment 

Marine water 

after 

treatment 

79-08-3 

Monobromoacetic acid 

(MBAA) < 1.0 < 1.0 < 1.0 < 1.0

631-64-1 

Dibromoacetic acid 

(DBAA) < 1.0 < 1.0 < 1.0 < 1.0

75-96-7 

Tribromoacetic acid 

(TBAA) < 1.0 < 1.0 < 1.0 < 1.0

5589-96-8 

Bromochloroacetic acid 

(BCAA) < 1.0 < 1.0 < 1.0 < 1.0

5278-95-5 

Dibromochloroacetic acid 

(DBCAA) < 1.0 < 1.0 < 1.0 < 1.0

71133-14-7 

Dichlorobromoacetic acid 

(DCBAA) < 1.0 < 1.0 < 1.0 < 1.0

Bromophenols (μg/L) 

615-58-7 2,4-dibromophenol <0.01 <0.01 <0.01 <0.01

608-33-3 2,6-dibromophenol <0.02 <0.02 <0.02 <0.02

118-79-6 2,4,6-tribromophenol <0.04 <0.04 <0.04 <0.04

Acetonitrils (μg/L) 

3252-43-5 Dibromoacetonitrile < 1.0 < 1.0 < 1.0 < 1.0

83463-62-2 Bromochloroacetonitrile < 1.0 < 1.0 < 1.0 < 1.0

The detection limit for the haloacetic acids is high compared to the PNEC (M), which in some 

cases are as low as 0.02 μg/L. This, however, does not give rise to critical PEC/PNEC ratios. 

4.2 Whole effluent ecotoxicity test 

The water samples were collected by personnel from DESMI Ocean Guard A/S in acid-rinsed 

heat-treated glass bottles delivered by DHI. The test waters were collected on 2 July 2009 from 

a lake at Aalborg University (freshwater) and Aalborg harbour (marine water), respectively. 

These locations were chosen by personnel from Ocean Guard A/S. The waters were treated by 

DESMI Ocean Guard A/S ballast water treatment facility. On 2 July 2009, immediately after 

treatment, samples of treated and untreated fresh water and marine water were forwarded to DHI 

by courier and received at DHI at 15:15, less than 6 hours from sampling. Testing was initiated 

immediately after arrival at DHI. All acute toxicity tests were performed by experienced 

personnel at DHI in a laboratory which is authorized to carry out studies in compliance with the 

OECD Principles of Good Laboratory Practice (GLP). 
MEPC 60/2/4 

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The following acute toxicity tests were performed on the treated freshwater and marine water 

samples, respectively: 

• Growth inhibition test with the freshwater microalga Pseudokirchneriella subcapitata

• Growth inhibition test with the marine microalga Skeletonema costatum

• Acute toxicity test with freshwater crustacean Daphnia magna

• Acute toxicity test with the marine crustacean Acartia tonsa

• Acute toxicity test with zebra fish (Danio rerio) – freshwater 

A summary of the obtained results are shown in Table 4. 

Table 4 : Results from the acute test with treated water samples 

Test organism Sample NOEC 

(mL/L)

LOEC 

(mL/L)

L(E)C10 

(mL/L) 

L(E)C50

(mL/L) 

Freshwater samples 

Pseudokirchneriella 

subcapitata Treated freshwater ≥800 >800 >800 >800 

Daphnia magna Treated freshwater >1,000 >1,000 

Zera fish (Danio rerio) Treated freshwater >1,000 >1,000 

Marine water samples 

Skeletonema costatum Treated marine 

water ≥800 >800 >800 >800 

Acartia tonsa Treated marine 

water >1,000 >1,000 

No acute toxicity of neither DESMI Ocean Guard treated freshwater nor DESMI Ocean Guard 

treated marine was detected. All NOECs and LOECs were higher than 800 mL/L or 1000 mL/L. 

4.3 Theoretical evaluation of fate and effect properties of Active Substances and 

potential by-product 

4.3.1 Fate properties 

The fate properties are used in the MAM-PEC calculations, from which the 

Predicted Environmental Concentrations (PEC) are derived. The respective fate properties of the 

chemicals in question are depicted in Table 5. 
MEPC 60/2/4 

ANNEX Page 30 I:\MEPC\60\2-4.doc 

Table 5 : Fate properties 

CAS No. Substance Mw g/mole MP oC BP oC log KOW log KOC Sw mg/L Psat Pa H Pa m3/mole Red. potential mV 7722-84-1 Hydrogen peroxide 34 -0.43 152 -1.57 1.2 1,000,000 263 1.7·10-2 10028-15-6 Ozone 48 -193 -112 -0.87 1.4 85,201 2.5·10-3 7.9·103 (F) 1.8·104 (M) 7632-00-0 Nitrite* 68 - - -3.7 1.4 82,000 - 0 7681-52-9 Sodium hypochlorite 74 310 708 -3.42 1.16 1,000,000 1.4·10-11 1.0·10-15 13824-96-9 Sodium hypobromite 119 319 728 -3.33 1.16 1,000,000 1.9·10-15 2.3·10-19 67-66-3 Trichloromethane 119 -64 61 1.97 1.55 8,000 2.1·104 3.1·102 -2.754 75-27-4 Dichlorobromomethane 164 -56 118 2 1.55 1,287 7.7·103 9.7·102 -2.632 124-48-1 Dibromochloromethane 208 -34 143 2.16 1.55 567 2.1·103 7.6·102 -2.51 75-25-2 Tribromomethane 253 -12 167 2.4 1.55 204 7.1·102 54 -2.4 79-11-8 Monochloroacetic acid 95 63 189 0.22 0.08 3,1700,00 8.7 2.6·10-4 -3.081 79-43-6 Dichloroacetic acid 129 24 201 0.92 0.28 37,760 8.9·10-1 3.0·10-3 -3.42 76-03-9 Trichloroacetic acid 163 56 197 1.33 0.44 1,300,000 2.5·101 3.2·10-3 -3.485 79-08-3 Monobromoacetic acid 139 29 193 0.41 0.08 93,790 1.7·101 2.6·10-2 -2.903 631-64-1 Dibromoacetic acid 218 54 243 0.7 0.28 22,140 3.1 3.0·10-2 -2.926 5589-96-8 Bromochloroacetic acid 173 36 223 0.61 0.28 44,270 1.8·101 7.2·10-2 -3.215 71133-14-7 Dichlorobromoacetic acid 208 48 235 1.53 0.44 4,869 4.8 2.0·10-1 -3.368 5278-95-5 Dibromochloroacetic 252 68 264 1.62 0.44 2,353 6.9·10-1 7.4·10-2 -3.329 75-96-7 Tribromoacetic acid 297 87 290 1.71 0.44 1,102 3.7·10-2 1.0·10-2 -3.342 3252-43-5 Dibromoacetonitrile 199 7 204 0.47 1.11 9,600 4.0·101 8.3·10-1 -2.842 83463-62-1 Bromochloroacetonitrile 154 -15 181 0.38 1.11 18,720 1.2·102 0.0 -2.82 615-58-7 2,4-dibromophenol 252 71 270 3.22 2.86 156 2.1 3.5 -2.732 608-33-3 2,6-dibromophenol 252 71 270 3.36 2.87 119 5.7·10-1 1.2 -2.401 118-79-6 2,4,6-tribromophenol 331 94 244 4.13 3.07 50 4.2·10-2 2.8·10-1 -1.772 106-93-4 1,2-dibromoethane 188 9-10 131 1.96 1.64 4,040 2.1·104 9.6·102 -2.017 96-12-8 1,2-dibromo-3-chloropropane 236 -7 197 2.96 2.12 83 5.9·101 1.7·102 -1.66 96-18-4 1,2,3-trichloropropane 147 -47 162 2.27 2.12 897 3.6·102 3.0·101 -1.583 95-49-8 2-chlorotoluene 127 -27 159 3.42 2.65 114 3.6·102 3.9·102 -3.577 106-43-4 4-chlorotoluene 127 -27 162 3.33 2.64 136 3.0·102 2.8·102 -3.61 608-21-9 1,2,3-tribromobenzene 315 65 264 4.66 2.87 1 4.4·10-1 1.3·102 -2.788 * Sodium nitrite used as model substance for Nitrite ** In marine water ozone is assumed to immediately be transformed 100% into hypobromite 

 Shaded cells indicate when the PBT criteria for persistence are exceeded 
MEPC 60/2/4 

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4.3.2 Persistence, Bioaccumulation and Toxicity (PBT) 

The criteria for a substance to be characterized as a PBT is described in Procedure (G9), 

Table 1. 

Persistence 

The substances exceeding the criteria for persistence are shown as shaded cells in Table 5 

above. None of these substances were measured in concentrations above the detection 

limit for the respective chemical analysis. 

Bioaccumulation 

As shown in Table 5 all substances have a BCF < 100, except 2,4,6-tribromophenol, 

which has a BCF of 513. Therefore, none of the substances are fulfilling the criteria on 

bioaccumulation stated in Procedure (G9), Table 1 (BCF > 2,000). 

Toxicity 

In general, few studies of chronic toxicity are considered to be reliable, and often the 

documentation of experimental set-ups is poor. Information on acute toxicity is more 

abundant. With the data available none of the evaluated substances were having NOEC 

values below the criteria for toxicity (NOEC < 0.01 mg/L). 

4.3.3 Endocrine Disrupting Chemicals (EDC) 

None of the substances evaluated are on the EU prioritization list for endocrine disrupting 

substances. 

4.4 Ecotoxicity 

Acute and chronic ecotoxicity data has been collected for deriving the Predicted No Effect 

Concentration (PNEC) which corresponds to the concentrations at which the substances do not 

exhibit a risk to water-living organisms. The principles described in the IMO guidance document 

on risk assessment of chemical substances were applied for the derivation of the PNEC values. 

The respective PNEC values are depicted in Table 6. Shaded cells indicate when the PNEC value 

is below the detection limit of the chemical analysis of the respective substance. 

Nitrite was the only compound detected in concentrations above the detection limit 

(see Table 6). Compared to the initial concentration (concentration in untreated freshwater) the 

concentration was increased by 0.05 mg/L. Generally, the toxicity of Nitrite to fish even occurs at 

natural concentrations. The toxicity of Nitrite depends on a large number of factors, the most 

important being water chemistry and especially chloride concentration. According to data 

found in PAN Database the acute toxicity towards algae, crustaceans and fish varies 

between 27 and 226 mg nitrite/L. A recent study performed by Kroupova et al. 2008 showed an 

acute toxicity towards Ocorhynchus mykiss of 11.2 mg Nitrite/L. This value is used in the 

following risk assessment. 
MEPC 60/2/4 

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Table 6 : Derived PNEC values (μg/L). Shaded cells indicate when the 

PNEC value is below the detection limit of the chemical analysis. 

Bold values indicate when the measured concentration in 

treated water is above the PNEC value 

CAS No. Substance 

PNEC 

(μg/l) 

(F) 

PNEC 

(μg/l) 

(M) 

Safety 

factor 

(F) 

Safety 

factor 

(M) 

7722-84-1 Hydrogen peroxide 2.3 1.2 1000 1000 

10028-15-6 Ozone 0.07 0.007 1000 10000 

7632-00-0 Nitrite 11 1.1 1000 10000 

7681-52-9 Sodium hypochlorite 0.04* 0.04* - - 

13824-96-9 Sodium hypobromite 0.04* 0.04* - - 

67-66-3 Trichloromethane 146 15 1000 10000 

75-27-4 Dichlorobromomethane 640 64 10 100 

124-48-1 Dibromochloromethane 6. 0.6 10 100 

75-25-2 Tribromomethane 339 34 10 100 

79-11-8 Monochloroacetic acid 0.58 0.058 1000 10000 

79-43-6 Dichloroacetic acid 106 11 1000 10000 

76-03-9 Trichloroacetic acid 0.2 0.02 1000 10000 

79-08-3 Monobromoacetic acid 0.2 0.02 1000 10000 

631-64-1 Dibromoacetic acid 62 6 1000 10000 

5589-96-8 Bromochloroacetic acid 179** 19** 1000 10000 

71133-14-7 Dichlorobromoacetic acid 0.25** 0.03** 1000 10000 

5278-95-5 Dibromochloroacetic acid 0.31** 0.03** 1000 10000 

75-96-7 Tribromoacetic acid 279 28 1000 10000 

3252-43-5 Dibromoacetonitrile 0.55 0.055 1000 10000 

83463-62-1 Bromochloroacetonitrile 0.43 0.04 1000 10000 

615-58-7 2,4-dibromophenol 2.78 0.28 1000 10000 

608-33-3 2,6-dibromophenol 3.15 0.315 1000 10000 

118-79-6 2,4,6-tribromophenol 0.22 0.022 1000 10000 

96-12-8 1,2-dibromo-3-chloropropane 19 1.9 1000 10000 

96-18-4 1,2,3-trichloropropane 4.1 0.41 1000 10000 

95-49-8 2-chlorotoluene 0.7 0.07 1000 10000 

106-43-4 4-chlorotoluene 32 3.2 10 100 

*) Value given as TRC. Value equivalent to 0.04 FAC 

**) Calculated assuming same molar ecotoxicity of chlorine and bromine 

compound. 

4.5 Prediction of discharge and environmental substance concentrations: MAM-PEC 

MAM-PEC calculations were performed for the substances where the PNEC value is below the 

detection limit of the chemical analysis. In addition, the MAM-PEC calculations were performed 

for whole effluent. 

The start concentrations used for the MAM-PEC modelling are depicted in Table 7. All 

concentrations used are below the detection limits with nitrite in freshwater as the only 

exception. In this case, the nitrite was present in the test water. 
MEPC 60/2/4 

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Table 7 : Start concentrations of the substances released after 

DESMI Ocean Guard A/S treatment 

CAS No. Substance Marine water Fresh water Unit 

7632-00-0 Nitrite (NO2) 0.33 0.005* mg/L 

7722-84-1 Hydrogen peroxide (H2O2) 0.04* 0.04* mg/L 

10028-15-6 Ozone 0.01** 0.01** mg/L 

7681-52-9 HOCl/OCl- 0.04* 0.04* mg/L 

13824-96-9 HOBr/OBr- 0.04* 0.04* mg/L 

79-11-8 

Monochloroacetic acid 

(MCAA) 1.0* 1.0* μg/L 

76-03-9 Trichloroacetic acid (TCAA) 1.0* 1.0* μg/L 

79-08-3 

Monobromoacetic acid 

(MBAA) 1.0* 1.0* μg/L 

5278-95-5 

Dibromochloroacetic acid 

(DBCAA) 1.0* 1.0* μg/L 

71133-14-7 

Dichlorobromoacetic acid 

(DCBAA) 1.0* 1.0* μg/L 

3252-43-5 Dibromoacetonitrile 1.0* 1.0* μg/L 

83463-62-2 Bromochloroacetonitrile 1.0* 1.0* μg/L 

*) Detection limit for chemical analysis provided by Teknologisk Institut. 

**) Detection limit provided by DESMI. 
MEPC 60/2/4 

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The overall outcome of the MAM-PEC modelling is estimated PECs for the different 

compounds, potentially occurring in the DESMI-treated ballast water. The calculations were 

performed for an OECD-EU Commercial Harbour scenario. Selected PEC values (maximum 

total concentration) for freshwater and saline water are given in Table 8. 

Table 8 : MAM-PEC estimated PEC values for in OECD-EU Commercial Harbour 

saline water (SW) and freshwater (FW) scenarios 

CAS No. Substance PEC-SW PEC-FW Unit 

7632-00-0 Nitrite (NO2) 0.038 0.001 μg/L 

7722-84-1 

Hydrogen peroxide 

(H2O2) 0.042 0.027 μg/L 

10028-15-6 Ozone 0.025 0.025 μg/L 

7681-52-9 HOCl/OCl- 0.004 0.004 μg/L 

13824-96-9 HOBr/OBr- 0.004 0.004 μg/L 

79-11-8 

Monochloroacetic acid 

(MCAA) 0.006 0.006 μg/L 

76-03-9 

Trichloroacetic acid 

(TCAA) 0.007 0.007 μg/L 

79-08-3 

Monobromoacetic acid 

(MBAA) 0.006 0.006 μg/L 

5278-95-5 

Dibromochloroacetic 

acid (DBCAA) 0.007 0.007 μg/L 

71133-14-7 

Dichlorobromoacetic 

acid (DCBAA) 0.007 0.007 μg/L 

3252-43-5 Dibromoacetonitrile 0.007 0.007 μg/L 

83463-62-2 Bromochloroacetonitrile 0.007 0.007 μg/L 

4.6 Prediction of whole effluent discharge and environmental whole effluent 

concentration: MAM-PEC 

The MAM-PEC modelling on whole effluent was provided showing a daily release of 79096 m3

ballast water to the OECD-EU Commercial Harbour. This results in a maximum ballast water 

concentration of 6.55 mL/L. 
MEPC 60/2/4 

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4.7 Environmental risk assessment 

4.7.1 Assessment of discharged substances 

Table 9 gives calculated risk quotients for saline water for the various identified substances and 

Table 10 shows the calculated risk quotients for fresh water. 

Table 9 : Estimated risk quotients calculated for saline water based on 

MAM-PEC calculations. Where the PEC/PNEC ratio exceeds 1, 

this is indicated by shaded cells 

CAS No. Substance 

Concentrations in 

treated SW (μg/L) 

PEC-SW 

(μg/L) 

PNEC-SW 

(μg/L) PEC/PNEC-SW

7722-84-1 

Hydrogen peroxide 

(H2O2) 40 0.04 1.2 0.03 

10028-15-6 Ozone 10 0.025 0.007 3.6 

7681-52-9 HOCl/OCl- 40 0.004 0.04 0.11 

13824-96-9 HOBr/OBr- 40 0.004 0.04 0.11 

79-11-8 

Monochloroacetic acid 

(MCAA) 1 0.006 0.058 0.11 

76-03-9 

Trichloroacetic acid 

(TCAA) 1 0.007 0.02 0.36 

79-08-3 

Monobromoacetic acid 

(MBAA) 1 0.006 0.02 0.31 

5278-95-5 

Dibromochloroacetic acid 

(DBCAA) 1 0.007 0.03 0.24 

71133-14-7 

Dichlorobromoacetic acid 

(DCBAA) 1 0.007 0.03 0.24 

3252-43-5 Dibromoacetonitrile 1 0.007 0.055 0.13 

83463-62-2 Bromochloroacetonitrile 1 0.007 0.04 0.17 
MEPC 60/2/4 

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Table 10 : Estimated risk quotients calculated for fresh 

water based on MAM-PEC calculations 

CAS No. Substance 

Concentrations 

in treated 

FW 

(μg/L) 

PEC-FW 

(μg/L) 

PNEC-FW 

(μg/L) PEC/PNEC-FW 

7722-84-1 Hydrogen peroxide (H2O2) 40 0.027 1.2 0.02 

10028-15-6 Ozone 10 0.025 0.07 0.36 

7681-52-9 HOCl/OCl- 40 0.004 0.04 0.1 

13824-96-9 HOBr/OBr- 40 0.004 0.04 0.1 

79-11-8 

Monochloroacetic acid 

(MCAA) 1 0.006 0.58 0.01 

76-03-9 Trichloroacetic acid (TCAA) 1 0.007 0.2 0.04 

79-08-3 

Monobromoacetic acid 

(MBAA) 1 0.006 0.2 0.03 

5278-95-5 

Dibromochloroacetic acid 

(DBCAA) 1 0.007 0.25 0.03 

71133-14-7 

Dichlorobromoacetic acid 

(DCBAA) 1 0.007 0.31 0.02 

3252-43-5 Dibromoacetonitrile 1 0.007 0.55 0.01 

83463-62-2 Bromochloroacetonitrile 1 0.007 0.43 0.02 

Like most sum parameters, AOX and EOX include a large number of different compounds, 

including some of the substances mentioned in Table 9 and Table 10. Therefore, there is no 

specific PNEC value available for use in a risk assessment. 

AOX is a parameter, which is regulated by, e.g., HELCOM. For plants discharging into water 

bodies or connected to municipal sewerage system, HELCOM recommend that the concentration 

of AOX should not exceed 1,000 μg/L (HELCOM 1995). 

As seen from Table 9, the supply of AOX amounts to max 40 μg/L. AOX was 0.05 mg/L in 

treated marine water and 0.04 mg/L in fresh water, thus far below the amount which is 

recommended as a cut-off limit by HELCOM. 

4.7.2 Assessment of whole effluent 

The whole effluent concentration was calculated to 6.55 mL/L, which is more than a factor 

of 100 below the NOECs found in the acute tests. 
MEPC 60/2/4 

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4.8 Overall conclusion on the environmental risk assessment 

The risk assessment shown above is performed as a conservative estimation using the estimated 

maximum concentrations of potentially released Active Substances and by-products inside the 

harbour. Typically, the mean concentrations are a factor of 2-3 lower than the maximum 

concentrations while the concentrations in surrounding waters (water outside the harbour) 

are 10-30 times lower than the concentration in the harbour. Based on these conservative 

estimations, the following conclusions are drawn: 

• The concentration of whole effluent in the OECD commercial harbour 

amounts to 6.55 ml/L. 

• Acute ecotoxicity tests performed on algae, crustaceans and fish indicate no toxic 

effects up to 1,000 ml/L (100% undiluted treated ballast water). 

• Based on PEC/PNEC evaluation, only ozone in marine water poses a potential risk to 

the environment. 

• The calculations on ozone are very conservative and based on the detection limit for 

the chemical analysis of 0.01 mg/L. For Final Approval of the DESMI ballast water 

treatment system, a lower detection limit should, if possible, be applied. 

• None of the other evaluated substances shows a PEC/PNEC ratio above 1. 

• The release of AOX /EOX did not exceed the HELCOM cut-off limit of 1,000 μg/L 

in discharged water. 

• Based on the evaluated fate of the substances, none of the substances is expected to 

accumulate in sediments. 

4.9 Risk to safety of ship 

4.9.1 Increased corrosion 

The DESMI Ocean Guard technology is characterized by the absence of any oxidation residual 

after treatment. Therefore, no corrosion supporting or corrosion stimulating effects are connected 

to the technology. 

4.9.2 Fire and explosion 

Generally speaking, the major risks with ships are fire and flood. Regarding fire, safety is 

enhanced by implementing the following measures: 

- in case of fire occurring in the engine-room or in another room where the DESMI 

Ocean Guard system is installed, the system can be stopped from outside the room; 

and 

- in case of a fire alarm, the electric power supply to the system will be shut down. 
MEPC 60/2/4 

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The electrical and electronic parts of the DESMI Ocean Guard BWMS are intrinsically safe. 

There is no risk of fire or explosion associated with the system. 

4.9.3 Storage and handling of the substances 

Low concentration ozone gas is produced continuously during operation of the ballast water 

management system. It is injected instantaneously into the ballast water. 

No storage or handling of any chemical is needed apart from common detergents used for 

cleaning, etc. 

4.9.4 Contact with, or inhalation of, process products 

Ozone as Active Substance and the Relevant Chemicals may cause the following potential risk to 

shipboard personnel when this system operates: 

- hazard to respiratory organ by inhalation of ozone; and 

- hazard to eye and dermis by contact with ozone and Relevant Chemicals. 

4.9.5 Countermeasures for Ozone leakage 

This system is equipped with ozone gas sensorslocated at the ozone generating UV-unit, near the 

ozone injector and near the waste ozone destruction (reactor unit) unit so that ozone leakage can 

always be under surveillance. If leakage should be detected, a visible and audible alarm is raised, 

the UV lamps are automatically shut off and, consequently, the ozone production is stopped and 

the evacuation of shipboard personnel is urged. Portable ozone leak sensors are installed on board 

so that the ozone concentration can be measured by shipboard personnel at appropriate locations 

and inhalation of air containing ozone can be prevented. 

Goggles and protective masks are also provided on board. Caution plates are located near the 

ozone containing unitsto draw attention to the hazard. 

As ozone is a strong oxidizing substance, appropriate materials are used where ozone is present 

so that the integrity of the system is maintained and ozone leakage is prevented. 

4.9.6 Noise 

As the DESMI Ocean Guard BWMS technology includes only one water pump for operating the 

ozone injection system as a noise-generating component (besides the already existing ballast 

water pumps) the noise level generated by DESMI Ocean Guard BWMS will be below 

the permissible average noise at the work place of 85 dB(A), according 

to EC guidelines 2002/44/EG and 2003/10/EG (BGBI 2007). The pump used for the injection 

system is a conventional centrifugal pump. The noise level for the large scale BWMS will be 

measured in accordance with EC guidelines. 
MEPC 60/2/4 

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4.10 Human exposure scenario and risk assessment for crew and public 

The section below is an extract from the executive summary of “Preliminary chemical 

characterization, whole effluent toxicity and risk evaluation of treated ballast water 

for Basic Approval application” from DHI. The full report is enclosed in confidential material of 

this application. 

4.10.1 Occupational exposure 

Occupational exposure to Active Substances and their degradation products may occur in the 

following two situations: 

• Sampling from the system. However, sampling is expected only to be carried out by 

external technicians, and thus no exposure to the crew on the ship due to sampling is 

expected. 

• On the loading of the ballast tanks with water – The excessive air of the ballast tanks 

arising as air is replaced with water in the ballast tanks, and will be exhausted on 

board and humans on board may inhale some of this air. 

If the substance was not detected, the concentration in the water was assumed equal to the 

detection limit. The predicted concentrations in air were then compared with the OEL values 

found for the various substances for various countries, and the required dilution in order to have 

concentrations in the air below the OEL is calculated. The results of these calculations are shown 

in Table 12. The predicted concentration in the air at equilibrium is well below the various 

OEL values – except for dibromoethane, for which the predicted concentration in the air at 

equilibrium is slightly above the Dutch OEL value (indicated by shading in Table 111 below), 

but below all other OEL values, and for ozone where the concentration is above all known 

OEL values for ozone. This is mainly due to a very conservative estimate based on the detection 

limit for ozone, as no ozone was measured either in the treated fresh water or in the marine 

waters. 

 
MEPC 60/2/4 

ANNEX Page 40 I:\MEPC\60\2-4.doc 

Table 111 : Predicted concentrations in air compared with the OEL-values 

for the various substances for various countries 

Substance Ci (M)

μg/L 

Ci (F) 

μg/L 

Cair (M) 

mg/m3

Cair (F)

mg/m3 AT 

BE 

CZ 

CH 

DE 

DK 

EE 

ES 

EU 

FI 

FR 

GB 

GR 

HU 

IE 

IS 

LT 

LU 

LV 

NL 

Hydrogen peroxide 40 40 3.E-04 3.E-04 1.4 1.4 0.71 0.71 1.4 1.4 1.5 1.4 Ozone 10 10 8.E+01 3.E+01 0.2 0.2 0.1 0.2 0.2 0.12 Nitrite 5 330 Sodium hypochlorite 40 40 2.E-17 2.E-17 Sodium hypobromite 40 40 4.E-21 4.E-21 Trichloromethane 0.05 0.05 7.E-03 7.E-03 10 10 10 2.5 10 10 10 10 10 10 9.9 50 10 9.8 10 10 10 10 5 Dichlorobromomethane 0.02 0.02 8.E-03 8.E-03 Dibromochloromethane 0.02 0.02 6.E-03 6.E-03 Tribromomethane 0.02 0.02 5.E-04 5.E-04 5 5.3 5 5 5.3 5.2 5 5 5 5 5 Monochloroacetic acid 1 1 1.E-07 1.E-07 4 4 4 1.2 1 4 1 Dichloroacetic acid 1 1 1.E-06 1.E-06 2.7 4 4 Trichloroacetic acid 1 1 1.E-06 1.E-06 5 6.8 1 6.8 5 5 1 5 Monobromoacetic acid 1 1 1.E-05 1.E-05 Dibromoacetic acid 1 1 1.E-05 1.E-05 Bromochloroacetic acid 1 1 3.E-05 3.E-05 Dichlorobromoacetic acid 1 1 9.E-05 9.E-05 Dibromochloroacetic 1 1 3.E-05 3.E-05 Tribromoacetic acid 1 1 4.E-06 4.E-06 Dibromoacetonitrile 1 1 4.E-04 4.E-04 Bromochloroacetonitrile 1 1 0.E+00 2,4-dibromophenol 0.01 0.01 1.E-05 1.E-05 2,6-dibromophenol 0.02 0.02 1.E-05 1.E-05 2,4,6-tribromophenol 0.04 0.04 5.E-06 5.E-06 1,2-dibromoethane 0.02 0.02 8.E-03 8.E-03 0.8 1 1 3.9 0.78 3.9 4 4 1 0.002 1,2-dibromo-3-chloropropane 0.02 0.02 1.E-03 1.E-03 0.01 0.01 1,2,3-trichloropropane 0.02 0.02 3.E-04 3.E-04 300 61 0.6 300 18 300 300 60 2 2 0.108 2-Chlorotoluene 0.02 0.02 3.E-03 3.E-03 250 263 285 250 264 250 250 250 285 10 4-Chlorotoluene 0.02 0.02 2.E-03 2.E-03 10 1,2,3-tribromobenzene 0.05 0.05 3.E-03 3.E-03 
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The minimum dilution required for reaching a level below the OEL values for all considered 

substances was calculated to be 770 times. On the largest vessel (the worst case scenario) the 

estimated dilution achieved is 96 times (Table 12), thus approximately 8 times less than required 

on these initial calculations. 

Table 122 : Estimated dilution factors (F) 

DWT 

(Tons) BW (m3

) LENGTH 

(m) 

WIDTH 

(m) 

Qair

(m3/hr) 

Qballast 

(m3/hr) 

Dilution 

(F) 

6,615 1,832 100 15 270,000 153 1770 

14,215 4,857 150 22.5 405,000 405 1002 

30,547 11,359 200 30 540,000 947 571 

65,646 25,332 250 37.5 675,000 2,111 321 

141,074 55,360 300 45 810,000 4,613 177 

303,166 119,889 350 52.5 945,000 9,991 96 

4.10.2 Exposure via the environment 

Human exposure to substances in the ballast water may occur as: 

• Oral intake due to bioaccumulation of the substances in bivalves and fish 

• Oral, inhalative and dermal exposure during bathing in areas close to the ballast water 

outlet 

Table 13 shows the calculated total uptake of each substance, the applied Tolerable Daily Intake (TDI) 

values and the estimated risk quotients, which is the ratio between the calculated daily uptake and 

the TDI value. It is seen that the estimated total daily uptake from eating fish and swimming in 

the harbour is well below the TDI values except for 1,2-dibromoethane for a child who swims 

twice a day and inhaling air from the area. 

4.10.3 Overall conclusion on the human exposure assessment 

Exposure to humans from the treated ballast water may occur due to: 

• Inhalation from exhaust air emitted from the ballast tanks (occupational). The 

predicted concentration in the air for inhalation is far below existing OEL values 

except for ozone. The calculations on ozone are very conservative and based on a 

relatively high detection limit of 0.01 mg/L. For Final Approval of the DESMI ballast 

water treatment system a lower detection limit should be applied. If a conservative 

estimate using a lower detection limit for ozone still shows a potential risk, this risk 

has to be prevented by using, e.g., a respirator, avoiding contact with vent channels 

from the tanks or using local exhaust ventilation. 

• Exposure via the environment due to eating the fish from the harbour area and due to 

swimming in the harbour area is considered low as the predicted daily uptake 

considering all uptake routes simultaneously is far below existing TDI values, no risk 

to the public from the treated ballast water is expected besides for 1,2-dibromoethane 

for children swimming in the harbour and inhaling air. 
MEPC 60/2/4 

ANNEX Page 42 I:\MEPC\60\2-4.doc 

Table 13 : Calculated total daily uptake, TDI and risk quotients 

Marine 

Exposure 

(μg/kg 

bw/day) 

Exposure 

(μg/kg 

bw/day) 

Exposure 

(μg/kg 

bw/day) 

RQ 

(-) 

RQ 

(-) 

RQ 

(-) 

Exposure 

(μg/kg 

bw/day) 

E

Substance 

TDI 

(μg/kg 

body 

weight 

/day) Man Female Child Man Female Child Man 

Hydrogen peroxide 

- 

3.6E-04 4.0E-04 1.0E-03 - - - 2.3E-04 

Ozone 

- 

3.7E+01 3.5E+01 1.8E+02 - - - 1.6E+01 

Nitrite 46 3.2E-04 3.6E-04 8.7E-04 6.9E-06 7.7E-06 1.9E-05 5.8E-06 Sodium hypochlorite 324 3.7E-05 4.2E-05 1.0E-04 1.2E-07 1.3E-07 3.1E-07 3.7E-05 Sodium hypobromite 517 3.7E-05 4.2E-05 1.0E-04 7.2E-08 8.0E-08 2.0E-07 3.7E-05 Trichloromethane Cl3CH 10 3.6E-05 3.4E-05 1.7E-04 3.6E-06 3.4E-06 1.7E-05 3.6E-05 Dichlorobromomethane CHBrCl2 2.1 4.4E-05 4.2E-05 2.1E-04 2.1E-05 2.0E-05 9.9E-05 4.4E-05 Dibromochloromethane CHClBr2 30 3.5E-05 3.3E-05 1.6E-04 1.2E-06 1.1E-06 5.5E-06 3.5E-05 Tribromomethane Br3CH 25 2.5E-06 2.4E-06 1.2E-05 1.0E-07 9.7E-08 4.7E-07 2.5E-06 Monochloroacetic acid (MCAA) 3.5 5.1E-05 5.7E-05 1.4E-04 1.5E-05 1.6E-05 4.0E-05 5.1E-05 Dichloroacetic acid (DCAA) 40 5.1E-05 5.7E-05 1.4E-04 1.3E-06 1.4E-06 3.5E-06 5.1E-05 Trichloroacetic acid (TCAA) 40 4.6E-05 5.1E-05 1.3E-04 1.2E-06 1.3E-06 3.3E-06 4.6E-05 Monobromoacetic acid (MBAA) - 5.4E-05 6.0E-05 1.5E-04 - - - 5.4E-05 Dibromoacetic acid (DBAA) 20 5.5E-05 6.0E-05 1.6E-04 2.7E-06 3.0E-06 7.8E-06 5.5E-05 Bromochloroacetic acid (BCAA) - 6.0E-05 6.5E-05 1.8E-04 - - - 6.0E-05 Dichlorobromoacetic acid (DCBAA) - 8.8E-05 9.4E-05 3.0E-04 - - - 8.8E-05 Dibromochloroacetic acid (DBCAA) - 6.9E-05 7.6E-05 2.1E-04 - - - 6.9E-05 Tribromoacetic acid (TBAA) - 6.0E-05 6.7E-05 1.7E-04 - - - 6.0E-05 Dibromoacetonitrile 23 1.7E-04 1.7E-04 7.1E-04 7.6E-06 7.6E-06 3.1E-05 1.7E-04 
I:\MEPC\60\2-4.doc

Marine 

Exposure 

(μg/kg 

bw/day) 

Exposure 

(μg/kg 

bw/day) 

Exposure 

(μg/kg 

bw/day) 

RQ 

(-) 

RQ 

(-) 

RQ 

(-) 

Exposure 

(μg/kg 

bw/day) 

E

Substance 

TDI 

(μg/kg 

body 

weight 

/day) Man Female Child Man Female Child Man 

Bromochloroacetonitrile 0.06 5.7E-05 6.4E-05 1.6E-04 1.0E-03 1.1E-03 2.7E-03 5.7E-05 2,4-dibromophenol - 8.1E-06 8.3E-06 3.1E-05 - - - 8.1E-06 2,6-dibromophenol - 1.1E-05 1.2E-05 3.4E-05 - - - 1.1E-05 2,4,6-tribromophenol - 2.3E-04 2.7E-04 5.5E-04 - - - 2.3E-04 1,2-Dibromoethane 0.01 2.7E-03 2.5E-03 1.3E-02 2.4E-01 2.2E-01 1.1E+00 2.7E-03 1,2-dibromo-3-chloropropane 0.03 4.7E-04 4.4E-04 2.2E-03 1.6E-02 1.6E-02 7.7E-02 4.7E-04 1,2,3-trichloropropane - 8.7E-05 8.3E-05 4.0E-04 - - - 8.7E-05 2-chlorotoluene - 1.1E-03 1.1E-03 5.2E-03 - - - 1.1E-03 4-chlorotoluene - 7.9E-04 7.5E-04 3.7E-03 - - - 7.9E-04 1,2,3-tribromobenzene - 1.4E-03 1.4E-03 5.3E-03 - - - 1.4E-03 Trichloroacetic acid (TCAA) - 4.6E-05 5.1E-05 1.3E-04 - - - 2.3E-04 
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5 CONCLUSION 

During the DESMI Ocean Guard BWMS process, aquatic organisms will be affected by 

UV (photons) and ozone. Both Active Substances are short-lived and their presence is restricted 

to the duration of the UV application, locally to the treatment reactor. 

Exposure to the aquatic environment from substances termed Relevant Chemicals and other 

substances, which can be produced indirectly through photons and radicals, could occur after 

discharge of the treated ballast water. 

As shown by chemical analysis of water samples before and after ballast water treatment, 

concentrations of all observed substances were below the LoQ. Therefore, no indication of 

release of harmful substances, resulting in an increase of environmental concentrations could be 

observed. 

As there is no indication for the release of harmful substances, the actual potential for 

bioaccumulation is considered to be very low. Neither sediment toxicity, nor bioconcentration or 

magnification effects, including secondary poisoning are considered to be of concern. 

With regard to the predicted ozone concentration in air compared with OEL values (Table 11) no 

ozone has been measured at all. However, DESMI Ocean Guard is aware that when going to the 

large-scale test, the used apparatus for measuring potential ozone has to be with very fine 

detection values. 

From the Risk Assessment we have not identified unmanageable risks associated to the ship, its 

personnel or other persons and/or parties concerned, which are originated by the installation and 

operation of the DESMI Ocean Guard ballast water treatment system. 

On the basis of the results of analysis of several theoretical possible by-products and the risk 

assessment, it can be concluded that there is no indication for a risk to the aquatic environment 

and/or humans based on the treatment process of the DESMI Ocean Guard BWMS. 

5.1 Test report data quality 

5.1.1 DHI 

DHI is an independent research and consultancy organization, formed by merging Danish 

Hydraulic Institute, VKI – Institute for the Water Environment and Danish Toxicology Centre. 

DHI’s objectives are to build competence and promote technological development in areas 

relevant to water, environment and health in the fields of ecology and environmental chemistry, 

water resources, hydraulic engineering and hydrodynamics as well as other related fields. 

The Institute has a total staff of approximately 800, the majority of whom are professional 

engineers and scientists with post-graduate qualifications – 35% have a Ph.D. – and several years 

of consultancy and R&D experience. 
MEPC 60/2/4 

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DHI’s main office is located in Hørsholm, Denmark, and offices are located in Australia, 

Bulgaria, China, the Czech Republic, Denmark, France, Germany, India, Italy, Malaysia, 

New Zealand, Norway, Singapore, the Slovak Republic, Spain, Sweden, the United Arab 

Emirates and the United States. DHI has representative offices in Brazil, Japan, Thailand and 

Vietnam and also an extensive agents network. 

DHI has been authorized as an Approved Technological Service Institute by the Danish Minister 

of Science, Technology and Innovation. 

5.1.1.1 Quality, Safety and Environment 

All DHI’s activities are performed in accordance with its quality management system, which is 

based on the Institute’s objectives and policies and its commitment to quality, as stated in 

the Quality Manual and associated quality system documentation developed according to 

ISO 9001, ISO 17025 and ISO 14001. The Environmental laboratories perform testing accredited 

by DANAK (Danish Accreditation Scheme) and according to OECD’s principles for good 

laboratory practice (GLP). 

6 REFERENCES 

.1 Dorfman, L.M. and Adams: Reactivity of the hydroxyl radical in aqueous 

solutions, National Standard Reference System. Monograph NSRDS-NBS 46. 

National Bureau of Standards, 1973. 

.2 Glaze, William H. et al.: The Chemistry of Water Treatment Processes Involving 

Ozone, Hydrogen Peroxide and Ultraviolet Radiation. Ozone: Science & 

Engineering, vol.9:335-352, 87. 

.3 Hoigne J. and Bader H.: The role of hydroxyl radical reactions in ozonation 

processes in aqueous solutions. Water Research 10, p.377-386, 1976. 

.4 Morel, F.M.M. and J.G. Hering: Principles and Applications of Aquatic Chemistry 

(2nd ed.). John Wiley & Sons, New York, 1993. 

.5 Stumm, W. and Morgan: Aquatic Chemistry, Chemical Equilibria and Rates in 

Natural Waters. 3rd ed., A Wiley Interscience Publication, John Wiley & Sons, 

Inc., New York, 1996. 

.6 Hoigne, J.: Chemistry of aqueous ozone and transformation of pollutants by 

ozonation and advanced oxidation processes. in The Handbook of Environmental 

Chemistry, Vol. 5 Part C, Quality and Treatment of Drinking Water (edited by J. 

Hrubec) Springver-Verlag, Berlin, 1998. 

.7 Prado, J and S Esplugas: Comparison of Different Advanced Oxidation Processes 

Involving Ozone to Eliminate Atrazine. Ozone: Science & Engineering, vol. 21, No. 1, 

p. 39-52, 1999. 

.8 Japan: HARMFUL AQUATIC ORGANISMS IN BALLAST WATER 

Application for Final Approval of the Special Pipe Hybrid, Ballast Water 

Management System (combined with Ozone treatment). MEPC 59/2/1, 2008. 
MEPC 60/2/4 

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I:\MEPC\60\2-4.doc 

.9 Germany: HARMFUL AQUATIC ORGANISMS IN BALLAST WATER, 

Application for Basic Approval of the AquaTriComb Ballast Water Treatment 

System. MEPC 59/2/8, 2008. 

.10 Summerfelt, Steven T. et al. Aquacultural Engineering volume 32, Issue 1, 

Journal: 2003 Aquacultural Engineering Society Issues Forum, Dec. 2004, p. 209-223. 

.11 Krasner, S. T. et al.: Formation and Control of Bromate During Ozonation of 

Waters Containing Bromide. Journal of AWWA, 85:1:73, Jan. 1993. 

.12 Siddiqui, M. S. et al.: Alternative Strategies for Removing Bromate. Journal of 

AWWA, vol. 86 (10), 1994, p. 81-95. 

.13 Wagler, J. L. and J. P. Jr Malley: The Removal of MTBE from a Model 

Groundwater using UV/Peroxide Oxidation. Journal of New England Water 

Works Association, 1994, p. 236-243. 

.14 Peyton, G. R. et al.: Effect of Bicarbonate Alkalinity on Performance of Advanced 

Oxidation Processes. AWWARF, 1998. 

.15 Liang, S. et al.: Oxidation of MTBE by Ozone and Peroxone. Journal American 

Water Works Association, Vol. 91 (6), 1999, p. 104-114. 

.16 Von Gunten, U. and J. Hoigne: Bromate Formation during Ozonation of 

Bromide-Containing Waters: Interaction of Ozone and Hydroxyl Radical 

Reactions. Environmental Science and Technology, v. 28, 1994, p. 1234-1242. 

.17 Buxton, G.V. et al.: Critical Review of Rate Constants for Hydrated Electrons, 

Hydrogen Atoms and Hydroxyl Radicals (OH/O-) in Aqueous Solution. Journal 

Physical and Chemical Reference Data, vol. 17, No. 2, 1988, p. 13. 

.18 Ozone introduction. Published by Lenntech Water treatment & air purification 

Holding B.V. Internet address: 

http://www.lenntech.com/ozone/ozone-introduction.htm.

.19 Ozone decomposition. Published by Lenntech Water treatment & air purification 

Holding B.V. Internet address: 

http://www.lenntech.com/ozone/ozone-decomposition.htm.

.20 Kroupova H, Machova J, Piackova V, Blahova J, Dobsikova R, Novotny L, 

Svobodova Z (2008): Effects of subchronic nitrite exposure on rainbow trout 

(Oncorhynchus mykiss). Ecotoxicology and Environmental Safety 71:813-820. 

___________