What is Ozone?

Ozone (O3) is a gas allotrope of oxygen. At normal temperature and pressure, it is an unstable gas that rapidly decomposes to return to its oxygen molecule (O2). Due to this characteristic, it cannot be stored or packed in a container, but must be generated on-site and used immediately.  

Isn't ozone useful in drinking water treatment plant?

Yes. Ozone is a strong oxidizer agent than chlorine. Extremely effective disinfection. Kill bacteria 100%. Remove odor, color & other impurities increase the taste of water. Most powerful than any other technology.
 

Isn’t ozone bad for the environment?

Ozone has a half life on the order of minutes when dissolved in water. Half life is the time it takes for half of the ozone to revert back to oxygen. Therefore, ozone must be generated on site and constantly introduced into the water to be effective.

How long does the ozone last?

As soon as ozone is formed in the generator and dispersed in a room, it will start to revert back to oxygen. This step occurs by several processes including the following: Oxidation reactions with an organic material such as odors or smoke. Reactions with bacteria etc., which again consumes ozone by oxidation reactions. Additionally ozone breaks down thermally. Higher temperatures destroy ozone quicker than lower temperatures. The ozone that remains is referred to as Residual Ozone.

"Residual" ozone created will return to oxygen usually within 30 minutes, in amounts equal to half its level. What this means is that after each subsequent 30 minute period there would be half as much residual ozone left at the end of the period as was present at the beginning of the period. In practice the half life is usually less than 30 minutes due to temperature, dust, and other contaminants in the air. Therefore, ozone, while very powerful, doesn't last long.

Will the odor come back?

No. If ozone is applied properly it destroys the source of the odor. Treatment times may vary depending on the strength of the odor but close to 99% of ozone treatments are successful.

What is the right level of ozone?

The right level is when all the generated ozone is being consumed. This only applies to continuous ozone use in occupied environments, not for shock treating. However, this is difficult to attain because it becomes a balancing act. Initially the machine's output is set high to get rid of the problem odor as quickly as possible. As this is being accomplished less ozone is required for the diminishing odor etc., thereby leaving some residual ozone in the air. If the machine output is not turned down, then more residual ozone will remain. If a strong smell of ozone is noticed, then there is more ozone present than is required. Simply decrease the rheostat (output level control). With ozone, MORE IS NOT CONSIDERED BETTER! One must be careful when using ozone in a occupied environment.

Is ozone harmful and what if any are the long term effects?

Ozone has been known for almost a century, so a great deal is known about it. Several regulatory agencies, including the Occupational Safety and Health Administration (OSHA), have stipulated that the safe allowable level of residual is 0.10-ppm (parts per million). Note that this permissible level is for continuous exposure throughout an entire 8 hour day. There is also a short-term exposure limit for ozone of 0.3ppm calculated as a 15-minute time-weighted average concentration.
The temporary affects of such a low exposure would range from headaches, to sore throats, irritation in the eyes, and nose. No long term effects have ever been documented from ozone exposure.