Myth of Chemical Free swimming pool


Many ozone manufacturers come up with very exciting proposals for swimming pool water treatment.  Chemical free treatment concept is very exciting to hear and tempting to pool owners. The main issue for most pool owners is the toxicity associated with the use of chlorine as a disinfectant in swimming pools. What is this chemical free treatment in swimming pool these ozone manufacturers are talking about? Is it ever possible?

The answer is always a big NO. Why?  The reason is that swimming pool water is often contaminated with numerous bacteria, virus , body oils, bird droppings, pseudomonas from landscaping, legionella, Giardia and many more .  Most of these contaminants are never addressed in pool water treatment. Most of them have serious consequences to pool users health. Hence any pool water treatment regime has to be comprehensive to address all of them. No compromise here

Chemical free treatment;   It means there is no chlorine usage, no usage of chemicals for coagulation, no usage of anti alage chemicals, no usage of acids.

Can ozone replace all of them?

The answer again is No. Ozone is not a magical wand to replace all these chemicals. Many of these chemicals play their role and a pool treatment has to be comprehensive, covering the entire spectrum of contaminants in the pool. Ozone will only replace chlorine as the primary disinfection and there is no alternative for the presence residual disinfectant in the pool and because no ozone residual is allowed in the pool (safety issues and all residual ozone must be removed before water enters the pool) , residual chlorine is the only viable alternative.

Some ozone manufacturers do recommend a small ozone residual of 0.05-0.01 ppm in the water that can totally get away from chlorine addition. For this you need to measure and control ozone residual in the water and require expensive measuring equipment and strict controls . Not always accepted by the pool owner , especially in India . So you would not want to take this risk . Also international standards quantify residual ozone on the surface of the pool water , a difficult measuring aspect and co relating residual ozone in the pool to the expected residual ozone at the surface of water is always going to be in accurate

Chlorine is the main chemical that is the cause of all the evolution of the so called chemical free treatment . But chlorine can never be replaced. It is the only chemical that can protect the water in the pool when contaminants are introduced.  Neither UV or ozone or any other chemical can replace chlorine. But chlorine can be made safe with the use of ozone . Use of ozone ensures chlorine toxicity is reduced or removed totally

What about claims of using ozone and UV together?    This is known as AOP (advanced oxidation process) and used only in indoor pools.  Indoor pools have reduced contaminants introduced into the pool and could be an ideal candidate for a CHLORINE FREE pool  (not Chemical free pool), since we still need to use other chemicals for flocculation, pH control etc . If the Indoor pool has a large bather load , often residual chlorine is also  used along with Ozone  . Moreover the UV lamps ideal for  combination with ozone is a medium pressure lamp (not used commonly in India except for certain applications) . Use of ozone alone does not mean chemical free treatment.

 Claims that chlorine free pools are following German and Australian standards is totally wrong as both Australian and German standards require complete removal of ozone before it enters the pool and maintaining residual chlorine at 0.5 ppm.  Few unsuspecting clients in India have fallen in prey to these chlorine free concepts which is just not safe for the swimmers. It is suggested to any client that he verifies these standards before accepting any such proposal from ozone manufactures to ensure that what he gets is totally safe for his and his family’s health

So next time when an ozone manufacture talks to you of chemical free treatment ask these questions and you may not  get the correct  answer. Ozone with residual chlorine alone is a better and safer combination   for pool water treatment

Buyers must exercise their right while buying an ozone generator

Recently I was called to a fairly large company to check on an ozone system installed for water treatment . They were not getting results . They were sold a 500 grams ozone system by an Indian manufacturer . against our will be were coaxed to check the ozone production and found that the unit was generating only 70  grams . This was confirmed also by the actual power consumption of the unit . There was nothing the buyer could do at this stage as the manufacture was giving ll sorts of excuses for non performances and shifting the blame to the engineering of the contact tanks, water quality and what not.

these situations do not happen in developed countries and it is high time we became sensitive to these tall claims of few irresponsible ozone manufactures .Buyers , consultants  must exercise their rights  enforcing performance as claimed/guaranteed

Today OTSIL has replaced more than 30 units of other ozone manufacturers within the last 2 years – All of them within warranty period. . We do not actually like it  and are frustrated ourselves . Will it Change ?

Thank You to my mentors

Rip Rice & Allan Pryor and few others not to mention, have been stalwarts in the ozone Industry There is not one article on ozone that would not have their names as references . They created world ozone awareness . If they had been to themselves , if they had been selfish , I could imagine what the status of the ozone Industry would be today.

Some of other colleagues in ozone  whom I want to openly  acknowledge , Guys who have taught me so much and made me what I am today.  Jean Yves Perrot ( where are you Sir ?)  Loius Benard Wiart , Jean Christophe Hostachy  , Florian Mills ( Suez) ,  Harald Staple and Marco Rosner and many others .  Over 20 years association . These  are some who have been my mentors . My inspiration . Thank you guys . You have been wholly selfless.

time to pay back , I have complied this Ozone 101 . A very simple compilation that put together all what I have been taught in ozone . Join Ozone users In India LinkedIn group I created and request one and know all about ozone . We need more members in India to join  with world  Group . this brings befit to India

Making Ozone Use Safer In India – We value Life


Ozone Generators are like capacitors . They operate at very high Voltage. The dielectrics can store power even when the mains are off . Do not operate ozone systems with panel doors open. It is advisable for users not to service systems by themselves unless they have been sufficiently trained or under supervision of manufacture.  Always disconnect power before you attempt to service an ozone system . Always ground the electrodes first before service. This grounding will discharge an accumulated power within the dielectrics.  A good ozone system will provide for these safety. It is manufactures responsibility to warn users .Safety manuals should be provided. safety training should be part of handing over of systems

Also ozone systems have strong electro magnetic fields . It is important for the user to know that persons with pace makers should not be allowed to go near an operating ozone system . The electro magnetic fields could cause the pace make to misbehave . Have you been told about this earlier ?

We at OTSIL put safety first. We value life. Come to OTSIL for safe reliable ozone systems

Transparency in Business is the essence to survive

OTSIL  has always believed in being transparency to its clients . While being transparent to its employees is a managements philosophy , being transparent to its clients is Mandatory .  One article that was published has impressed us       :

OTSIL s transparency can be seen by the clients in the information we provide to clients in design, testing procedures , and documentation we provide with our equipment . We call it GMAAP   ( Good Manufacturing and Application practices )

Never has there been a single  instant where we hide even the smallest and least important information from our clients . If we are at fault , we readily accept and offer remedial solutions. We do not run away .

Transparency is the essence . Come to OTSIL for ozone solutions and you would realize why we are most preferred in India

Blogging for ozone awareness

Reliable large ozone systems from OTSIL

There are very few large ozone generators manufactures around the world . Local manufacturers have have claimed to have installed large ozone systems have all failed . This is because you cannot manufacture ozone systems without basic research facility   . You cannot test your product at site . There should be an history of reliable working of the ozone generator .  This has made ozone systems high capital intensive and too dependent on few manufacturers .

Other important issues that are lacking is the availability of local ozone expertise and above all local service network for instant service. All claims of fast service would be exposed when there is a shut down for months for spare parts or service personnel to arrive at site.  You cannot force the clients to maintain inventory of expensive spare parts .

No ozone manufacture around the world manufacturer all the four components of the ozone system –  The power Board , the inverter , the transformer and the dielectrics . Except the dielectrics , all the components are out sourced . This appear to be the main reason for long delivery periods , delays in services and supply of spare parts

The presence of local engineering team is of utmost importance in large projects . This does not happen most of the time .

the other factor is that large ozone systems being assembled like computers and supplied to clients .  This is a big danger. The individual components of Inverter, transformer, dielectrics have to be integrated to work in unison and doing this at site is a disaster in waiting .

Oxygen is the heart of the ozone system. Experience reveal that most of the time it is the oxygen that is the culprit for ozone system failure . There need to be an integrated approach with the oxygen supplier and team work is essential

OTSIL provides one more reliable choice of large imported ozone systems in India . All components self manufactured , large working references around the world, established R & D activities on ozone technology, local service net work and highly knowledgeable local engineering team. Working in Unison with the oxygen supplier is an additional  advantage .

10 kg ozone system with PSA

Contact OTSIL for large ozone systems. Do not cut and paste specifications as this would surely cut down on the choice available to your client and increase his project costs

Making Ozone Use Safer In India – We value Life Ozone Safety Tip 1

Ozone Safety   TIP 1

Ozone systems are high voltage equipments. Voltage can exceed 9000 Volts.  The dielectrics that generate ozone are like Hugh capacitors. They can produce electrical shocks even after the power is disconnected.  Safety should come first. Some of the ozone generators manufactured locally have least consideration of safety aspects. They have the high voltage dielectrics mounted outside and behind the ozone control panel.  There is no protection against accidental contact by operators. I have seen in one installation in Mumbai where fencing is built around the ozone generator with lock and keys and this is recommended by the manufacturer. This is a ridiculous suggestion and totally misleading the client. We at OTSIL put safety foremost. All high voltage parts of our equipments are safely enclosed and made inaccessible to operators.  Our systems would pass any international safety audit. We must learn from International rules on safety standards and must also learn to   value life

As part of “Making ozone use safer in India “we will carry on this awareness programme so that in course of time we  reach international safety standards. Economy should not replace Safety


Reappearance of Pseudomanas after Dechlorination with SMBS

Many water treatment consultants would have faced this situation . Pseudomonas Nil when measured in the presence of residual chlorine . But the moment you use SMBS and remove the residual  chlorine , the Pseudomonas reappears . This is not uncommon if you know the behavioral pattern of these gram negative pathogens . They become sessile under unfavorable conditions and proliferate when the conditions are in their favor . When you use ozone in these conditions you need to be very careful and consider various factors to ensure total removal of these pathogens.  Many solution providers resort to high ozone dose without  really taking care the root cause

We have successfully provided solutions to many Pharmaceutical companies and shown how this should be done. Merely introducing high doses of  ozone will have very little effect.  Residual chlorine in process water does not mean that you have eradicated gram negative pathogens . Contact OTSIL  for reliable solutions in these situations .

Blogging for Ozone awareness

Aox Levels – Ozone Solutions

AOX levels – Ozone solution

Halogenated organic compounds are by products formed when chlorine is used as disinfectant in water and waste water

What is AOX
Adsorbable organically bound halogens (AOX) are a group of chemicals which can be adsorbed from water onto activated carbon. Most AOXs are compounds containing chlorine, but some also contain the similar elements bromine or iodine. The properties of AOXs vary: some evaporate easily (such as trichloromethane or chloroform); some are complex molecules such as dioxins and furans. THMs are part of AOX . AOX once formed cannot be destroyed by any chemical means or process. They have to be removed from water or waste water
Industry Water Guzzlers .Both the power plants as well as paper and pulp plant use more than 60% of the total water used in the country. Therefore they also discharge large quantities of water as waste  water . Both the power plants as well as the paper and pulp plants use lots of chlorine in their water treatment/process etc.

Where does it come from?

The main sources of AOX are from the chlorine chemicals used for treating cooling water in power plants and chlorine used to bleach fibres in the paper and pulp industry. AOX are  also formed during the routine chlorination (disinfection) of drinking water, swimming pools and industrial effluents.
How might it affect the environment?
Some AOXs are toxic to fish and aquatic organisms – Even at low concentrations. Many are persistent and have a tendency to accumulate in the environment which causes concern at global level. AOX once formed remains , either in the ground , polluting water source or in humans when they are consumed with water
How might exposure to it affect human health?
Exposure of AOXs to humans can occur through eating contaminated food ,, drinking contaminated water – and the fact that AOXs can concentrate up the food chain means that humans could be exposed to dangerous levels. The type and severity of adverse effects depend on the AOX in question. Some (such as dioxins) are known to be very toxic.  Many AOX/THMs are cancerous to humans and known to be precursors to rectum and colon cancer
In the UK (including Scotland) releases of AOX are controlled through the Pollution Prevention and Control (PPC) regulations. Chlorinated AOXs have been on the European Commission’s “black list” of toxic substances since 1976. In India pollution control board provide levels of AOX that industries must control in their waste water discharge

For example ,according the German classification  system  regarding AOX levels in river water, a concentration below 5mgCl/l is slightly polluted, 5–20mgCl/l is moderately polluted, 20–40mgCl/l is strongly polluted, and over 40mg Cl/l is very strongly polluted.17 This classification is relatively severe. It is Normal to  chose the maximum AOX data in river water as the nonpolluting level

In India paper and pulp plants have already taken conscious efforts to reduce AOX  levels  by replacing part of chlorine in their process with Ozone . ( ITC is the first plant ) The main by product of ozone chemistry is oxygen  it is an ideal choice to limit the formation of chlorinated byproducts (AOX) formed during conventional bleaching  processes . Similarly power plants have already taken conscious efforts to replace chlorine with ozone in cooling water treatment and in waste water treatment .

My New Activity – Blogging For Ozone Awareness

25 years of ozone experience now. It is time to pay back. For one to one interactions , I have started this blog and trying to spend what ever spare time is available with me on this activity . Initiating discussions, on various ozone topics could solicit interested persons to participate and try gather useful information. Internet is useful. But how many persons know which is right and which is wrong information. I have also taken time to prepare an Ozone 101 hand book of ozone and it is ready now. This is a non commercial activity of mine and is for free distribution to those showing genuine interest in ozone. The catch – you must register yourself in the linkedIn group I have created- ozone users in India . Go to and click on the Join ozone users in India and follow instructions . If you find it difficult just send me an email with all your contact details etc . I will mail you the pdf copy to you . You can also use that platform for discussions , there you could get information from others through their experience . V.Baratharaj