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FAQ's: OZONE SWIMMING POOLS / SPA BATHS









1) What is ozone?

Ozone is a highly reactive and unstable form of oxygen. Ozone is made up of three oxygen atoms together, written as O3. It is called activated tri-atomic oxygen. It is a gas and is denser than air. Ozone is the second most powerful sterilant in the world and its function is to destroy bacteria, viruses and odors. Ozone is nature's way of purifying the air we breathe. It is the distinctive “electric” odour smelled during and after thunderstorms. Ozone derives from the Greek word ozein, which means to smell. If natural ozone ceased to exist, life on this planet would also cease to exist.


2) Is ozone a new technology?

Ozone has been around as long as oxygen, sunshine and lightning. It was discovered and isolated in 1840 by C. F. Schonbeinwho noticed a unique odour during electrical sparking and electrolysis experiments. He realized that the odour was the same one he observed after a lightning flash. In 1886 de Meritens of France conducted the first experiments using this unique gas as a disinfectant. He proved that even minute amounts of ozonised air would sterilize polluted water. A few years later in 1891, the German scientist Frolich reported the bactericidal properties of ozone from pilot plant tests conducted at a drinking water treatment plant in Martinkenfeld, Germany. In 1893, the first drinking water treatment plant to employ ozone was built in Oudshoorn in the Netherlands. In 1906, the first large-scale water treatment facility built specifically to use ozone as a disinfectant was completed. By 1977, there were 1039 ozone drinking water treatment plants in Europe. Today there are more than 2000 water treatment plants worldwide using ozone. Ozone has been used in swimming pools and spas in France, Germany, Netherlands, and other European countries since the early 1950's and in the United States since about 1975.


3) How is Ozone Made?

Ozone can be produced artificially according the same principle as it occurs in nature, which means by UV light (ozone layer) or via corona-discharge (high voltages, thunderstorm). In both methods the connection between the oxygen molecules is broken up. Consequently oxygen radicals are produced, which connect with the oxygen molecule to O3 (ozone). For the production of ozone, corona discharge is used more because of the greater advantages of this method. Advantages are the lower costs for ozone production (more cost-efficient) and the greater durability of the system. For the feed inlet ambient air can be used as well as pure oxygen. For pure oxygen, oxygen generators can be used to concentrate oxygen out of air. When pure oxygen is used a higher concentration of ozone can be produced.


4) How does ozone work?

Ozone operates according the principle of oxidation. Ozone is faster than chlorine at killing bacteria because chlorine needs to diffuse through the cell wall and disrupt the bacteria's metabolism. Ozone, however, rips open the cell wall from the outside, causing the cell's contents to fall apart. This process is called cell lysing. With ozone, after destruction of the cell, all that is left is carbon dioxide, cell debris and water. As the ozone oxidizes material, it gets used up. Once it has done its job of oxidation, ozone reverts back to oxygen (O2). This additional oxygen in the water makes it taste good, smell good and gives it a sparkle. There are no toxic or hazardous byproducts.


5) What will Ozone Destroy?

Ozone kills bacteria, viruses, spores, mold, mildew, fungi, amoeba and cysts. Various factors play a role in effectiveness of ozone in the removal of contaminants, such as the amount of ozone, the concentration of ozone, and the contact time of ozone with the organism. Ozone will not usually eliminate all algae and hence an additional sanitizer must be added to the water to kill algae and provide protection during the time the ozone generator is not on.


6) Is Ozone an Oxidizer?

The easy answer is Yes. Ozone oxidizes at a rate of nearly 3000 times that of chlorine, and is twice as powerful. Ozone will also oxidize metals such as iron and manganese, as well as the bonds of many colour-producing contaminants like decaying leaves and grass. Once the bond is broken, the colour disappears.


7) What are the benefits of using ozone?


8) Can I stop using Bromine?

You will definitely reduce your chemical usage in your pool up to 90% depending on weather conditions and pool characteristics. Ozone provides better water quality and oxidizes many contaminants that bromine cannot. However, Ozone only lasts in pool water for a short period of time (15-30 minutes) therefore in order to provide lasting protection during times when ozone is not being injected, to control algae and to oxidize ammonia and swimmer waste, you must maintain a small residual of bromine (1.0 to 2.0 ppm of bromine) in the water.The longer the ozone system operates, the less bromine you will have to use to maintain water quality. Ozone will kill algae at the point of injection, not algae that are growing on the pool walls. Recommended Dosage for Sodium Bromide is 20g per 1000 Litres of water every 6 months.


9) How does ozone get into the water?

Ozone is a gas and it is only slightly soluble in water. It must be thoroughly dissolved in water so that the chemical reactions with contaminants can take place. The most common way in swimming pools is with a venturi injector, which is a device a 100mm in length with each end the same diameter (40/50mm) as the pool plumbing line. A section of pool piping is removed, and a venturi injector is installed. The injector’s diameter is smaller in the middle, similar to squeezing or pinching a hose. The water travelling into the injector begins to move faster. In the middle of the injector there is a small hole. As water is pumped through the plumbing and past the hole, a vacuum is created. The amount of vacuum is dependent on the amount of water flow through the injector – more water equals more vacuum. If a small flexible hose or tube is attached to this small hole, a liquid or gas can be drawn into the injector and mixed into the water.The goal is to make the smallest bubbles possible and to keep the bubbles in contact with the water for as long as possible. The ozone that does not get dissolved will kill or oxidise anything in the water.


10) How long will ozone last in my pool?

For the purification of water and air, it’s needed to produce ozone on-site. Because of its short half-life, ozone will decay soon when produced. The half life of ozone in water is about 30 minutes, which means that every half hour the ozone concentration will be reduced to half its initial concentration. For example, when you have 8 g/l, the concentration reduces every 30 minutes as follows: 8; 4; 2; 1; etc. In practice the half-life is shorter because a lot of factors can influence the half-life. Factors are temperature, pH, concentration and concentration and sort solutes. Because ozone reacts with all kinds of components, the concentration of ozone will reduce quickly. When most of the components are oxidized, the residual ozone will remain, and the concentration of ozone will reduce.


11) Will the temperature or humidity of the air or water affect ozone?

The temperature and humidity of the air will directly impact on the concentration of ozone gas produced. The more humid and the hotter the air, the less concentrated the ozone produced will be. Likewise the temperature of the water has a similar effect, the cooler the water the ozone is injected into, the more effective the ozone will be at removing contaminants! Heated pools require 10-15% more ozone than traditional pools.


12) Is ozone safe?

Ozone has been documented for over a century now, so quite a lot is known about it. OSHA - Occupational Safety and Health Agency has stipulated that the safe allowable level of residual ozone is .08 ppm. This is supposedly based upon the historical safety of ozone. Note that this permissible level is for continuous exposure throughout an entire 8 hour day for 5 days a week.No Federal or State agency can agree an what the maximum level of ozone exposure should be, so there is no standardization in maximum permissible ozone levels. That signifies these numbers are arbitrary, meaning they are not really sure of what a maximum sustainable ozone level should be. Since excess ozone gives off an unmistakable strong "bleach like" odor, one always know if too much is present in the air. In other words before ozone could possibly have any unsafe effects, a person would be greatly offended by it's bleach like odor. Ozone is safe to use in occupied areas because we notice it's unpleasant odor at very low levels and then have the ability to turn it down. Ozone generators, when used correctly will not exceed government guidelines for continuous safe exposure. Precautions should be taken, however, because the nose can loose it's ability to sense the ozone after a sustained period of time. If one senses a headache or sore through it may mean the ozone level is too high. The fact remains if the ozone level is much higher than is recommended to be consider safe, it would become so pungent that anyone could sense it. Ozone does this by becoming so offensive at high levels that we would not be able to stay in the environment for more than a very short period. This is much like what would happen if we entered a smoke filled room. No one has ever claimed a worker's related illness resulting from ozone exposure


13) Is ozone safe for my pool equipment?

Most pool systems these days come supplied with plumbing that is ozone-resistant eg. PVC piping. However, Ozone gas can corrode metal and other materials such as nylon and rubber. Care must be taken to check that all plumbing and piping between the injection point ( Venturi Injector ) and the point of entry to the pool are made of ozone-resistant materials. All our MightyZone systems are supplied with ozone-resistant accessories


14) Is ozone safe for swimmers?

Ozone dissolved in the water is pH neutral so the pH will not harm equipment or people. The amount of ozone added to the water is enough to kill bacteria, virus, cysts, mold and spores, but is safe and non-toxic to humans and pets - no red, irritated eyes and dry, itchy skin. When properly installed and plumbed all of the ozone generated will be dissolved in the water or used up oxidizing impurities in your water.


15) Does ozone affect water balance?

Ozone has a neutral pH (about 7.0) so it does not affect pH. Ozone has no calcium, no alkalinity, and no dissolved solids. Therefore, ozone does not affect water balance. It does remove trace amounts of metals such as iron or copper by oxidising them to their highest oxidation state. They will then precipitate out of the water and be trapped by your filter.


16) Can I run my pump and filter for fewer hours?

Ozone is only injected into your water when the pump is running. The longer you run the ozone generator (and your pump and filter), the better your resultant water quality will be and thereby reducing the need for residual chemicals. During summer / swimming season you should run your ozone generator, pump and filter a minimum of 12 hours each day. We recommend that you run your pump for 24hrs a day in summer. Up to 80% of the water treatment is done by your filter, so dont be afraid to use it. The extra electricity cost will be compensated by the savings on costly chemicals.


17) Will there be a visible change to my water?

Yes! When ozone is first introduced into your pool water and during the first 72 hours, your pool water may get cloudy. Ozone will begin to oxidise all of those particles and metals that your present sanitizer would otherwise leave in your pool. When these particles are oxidized, they form visible particles that are heavier than water and precipitate. Also, there will be pieces or fragments of the cells that ozone has destroyed. So the cloudiness that you may see is oxidized material, pieces and fragments of cells, and metal precipitates. Some of the dirt and debris in the water is too small to be trapped by the filter. These small-sized dirt particles have a weak electrical charge or pole. Because all the dirt particles have a negative charge, they repel each other like two magnets. They are so small that they are not affected by gravity and therefore won't settle out either. Ozone neutralizes these charges, which allows the particles to combine into large enough particles to be trapped by the filter. Once these particles are oxidized, neutralized and filtered, the water will have a definite "clarity and sparkle" that you may not have experienced before. In addition, after the ozone does its work, it reverts back to oxygen. This added oxygen will make the water look, feel and even taste better.


18) How must i prepare my pool before i install an ozone generator?


19) What special maintenance does ozone require?


20) What special maintenance does a MightyZone ozone generator require?


21) How do I know if there is enough ozone for proper sanitation?

This can be a difficult question to answer. Experts have not been able to develop a minimum or maximum level for ozone in swimming pool water because of the multiple variables involved such as air temperature, water temperature, humidity and bather load. Pool owners who have been using chlorine of bromine for a few seasons know how much sanitizer they use in a season or year. Installing an ozone generator in these pools has resulted in a significant reduction in the amount of chemical sanitizer used. The longer the ozone operates each day, the greater the reduction in chemical sanitizers. Pool owners have had reductions in sanitizer use of 50 to 90%. Your savings may vary based on pool usage factors. The MightyZone selected for your pool has been arrived at by field tests, best available information from other industries like drinking water,water-cooling towers and extensive lab testing. Ozone is not sold on the basis of being less expensive than other sanitizers such as chlorine and bromine are. Its value is in smoothness and sparkle to the pool water, elimination of the dry, itchy skin that chemicals can produce burning red eyes and bleached bathing suits. Other important advantages include reduced pool maintenance and reduced exposure to toxic chemicals in storing, handling and swimming.


22) Will my ozone generator help the ozone layer?

Ozone from a swimming pool ozone system will not add anything to the atmosphere or the ozone layer. When injected into the water properly, no ozone escapes into the atmosphere. Even if it does get into our atmosphere, it is like a drop in the ocean. Also, the ozone would have to be transported 9 to 18 miles up. The ozone layer that you may have heard about is a layer of mostly oxygen and ozone that is located in the lower stratosphere between altitudes of 9 and 18 miles. This ozone results almost entirely from oxygen (O2) splitting apart into two atoms of oxygen (O) by solar ultraviolet radiation (the sun's UV rays) and then combining with molecular oxygen (O2) to form ozone (O3). Atmospheric ozone plays a critical role for the earth by absorbing the ultraviolet radiation from the sun with a wavelength of between 240 and 320 nanometers (nm), which would otherwise be transmitted to the Earth's surface. This radiation is responsible for sunburn to human skin. In addition, the incidence of skin cancer has been statistically correlated with UV light intensities of 290 to 320 nm.




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