Ozone poses a threat to bathers?

[johnnyk]

Hi,

I recently bought a HotSpring spa that comes with the Freshwater III ozonator. I'm otherwise pleased with the product but I'm slightly worried about the health effects of the ozonator. If I have understood correctly, the ozone is injected into the water somewhere in the pipe system and is then carried into the spa. No excess ozone is removed after the injection. The ozone keeps on being injected even with the massage pumps on. So in theory, some ozone might reach the bathers that are sitting in the spa (inhaled ozone is dangerous). In addition, when the O3 is broken down in a matter of seconds,  I have heard that it might produce free oxygen radicals that can also be harmful to you. The water also smells funny (chemical or plastic smell) and makes me feel a bit ill. The smell was already there before adding chlorine for the first time.

Because of this I'm now thinking of removing the ozonator from the spa and relying solely on AquaFinesse (never tried it) and small amounts of chlorine.

Any thoughts on this?

[TwinCitiesHotSpring]

ozone can be bothersome to some people, I have a few customers who actually unplug the ozone when they are using the spa on a regular basis and will plug it back in when use becomes very sporadic (usually in the summer) just to help maintain clarity

[chem geek]

Usually, the ozonator operates when the circulation pump is on but is turned off when the spa jets are used.  This is because the ozonator tries to be off when you are using the spa and especially doesn't want to be aerated out of the water since, as you point out, that can be a health concern.  Residential spas don't have ozone degassing units, unlike commercial units that generally do, but that's mostly because the amount of ozone in the residential units is fairly low.

The advice about disconnecting the ozonator when one is frequently using the spa is good, especially when using chlorine since ozone reacts with chlorine so increases chlorine demand in between soaks.  The ozonator is useful if you use the spa every day or two, but not so much for once a week soaking.

[johnnyk]

Thanks for the replies. I now unplugged the ozonator just to easy my mind. I might plug it back in later or when I know I'm not using the tub for a longer period of time. The plugging/unplugging however has not been made very easy as you have to dismount the front panel first in order to gain access to the control panel. One solution could be to install a switch that's located somewhere outside the tub. I have to talk to my electrician about that.

[vangoghsear]

I would think it would be a simple enough thing for an electrician to wire in a manual switch to be used to disconnect the ozone for when the tub is in use.  May have to mount it by the disconnect and wire it back to the tub.  Pretty sure a good electrician would know where it could go.

[clover]

Hi,

.....I'm slightly worried about the health effects of the ozonator.....No excess ozone is removed after the injection.....So in theory, some ozone might reach the bathers that are sitting in the spa (inhaled ozone is dangerous). In addition.....I have heard that it might produce free oxygen radicals that can also be harmful to you.....Because of this I'm now thinking of removing the ozonator from the spa.....Any thoughts on this?

To alleviate your concerns, I would suggest you disconnect your ozone.  But, before you do that, I would also suggest that you research your fears and concerns for any supporting case documentation to support what you "hear".

Ozone has been in use in Hot Tubs for more than 20 years, and if you are right, you should be able to find multiple examples and supporting information that can support your concerns, like Life Guard Lung caused by chemical gasses. 

According to the EPA, all of the livestock in the country give off methane gas, as well as, the buffalo that roam the plains, and in doing so, they are damaging the atmosphere, by depleting the ozone in the upper atmosphere. 

While farmers and ranchers do not seem to have their health affected by this phenomenon, and my opinions may scoff at this idea as just a new way to promote more taxes and political agendas, there are those who believe what they “hear”.  Cows pass gas and that’s a fact, and many of us have been in the barnyard where the air is “rich”, but I don’t believe anyone’s health has been diminished because of it.

Disable your ozone if you feel it necessary, while everyone else continues to benefit from it maintaining their water. 

Incidentally, did you know when your pH is out of balance, chlorine properties change to chlorine gas that you can smell; are you aware that could be a carcinogen?  Inhaled chloramines also can be dangerous, but you can not unplug it.

[Dr. Spa™ Ret.]

methane is lighter than air, and quickly rises. Ozone is heavier than air, doesn't rise, and is therefore inhaled. These are scientific facts.

Can you show documentation scientific test results showing that ozone has ANY effect in spas, the way it is currently used? (there's plenty of documentation for municipal water systems...but ozone is applied in a completely different manner there, than in spas).

The American Academy of Allergy, Asthma and Immunology (AAAAI)  has concerns that high ozone levels result in the detrimental affects on the respiratory system including:

irritation of the respiratory system causing coughing and irritation in the throat and chest
a reduction in lung function, making breathing shallow and labored
inflammation and temporary damage to the lining of the lung

[clover]

Doc, I bow to your authority of facts about gas, and do not care to challenge your knowledge of methane. 

But, would you be suggesting ozone works in purification for public water systems, but it is not effective in other water, like spa water?  Of course, ozone has an influence on waterborne contaminants in all water, just as other elements do, and they all have the potential of going airborne into the air we breathe. 

Measures have been taken to minimize the excess of ozone off gassing through mixing, dispersion, and hang time, and to maximize the application of ozone while in water suspension.  It actually is quite effective when understood, and applied correctly.

My only point was to alleviate concerns, disconnect your ozone, but at least challenge the veracity of what you hear.  There are always two sides to every coin, but you only see one side, until you turn it over.

Can you show documentation scientific test results showing that ozone has NO effect in spas, the way it is currently used? Or, a negative ill effect?

[Dr. Spa™ Ret.]

In order for ozone to effectively sanitize water it has to be absorbed into the water. In order for ozone to be absorbed into water the water has to be pressurized to at least 60 psi (plus a minimum contact time of something like 26 seconds). No were in any spa do either of these occur.

I have asked every ozone manufacturer that makes units for spas to provide the results of any study of ozone being used in spas in the manor it is showing it does anything, positive. NONE have ever presented anything. It's not MY job to prove it doesn't work..it's THEIR job and the job of those that make the claims to PROVE it, with documented, peer reviewable, scientific studies.

The EPA has PLENTY of info on the negative and pollution aspects of ozone (Google, ozone dangers epa.. then try, ozone dangers respiratory)... When air quality is talked about, ozone, I believe, is the third pollutant on the list.

[clover]

.....NONE have ever presented anything. It's not MY job to prove it doesn't work..it's THEIR job and the job of those that make the claims to PROVE it.....

What's in it for me, to prove it to you, I deal in application, performance, and customer satisfation.  Unfortunately, chemical sales are down, as a result.

[chem geek]

I have seen numerous reports, including experiments having an ozonator on vs. off, that show significant changes in chlorine demand under conditions of no bather load vs. bather load that are consistent with ozone being in the water.  For some ozonators, the chlorine demand is roughly doubled from around 25% FC loss per day to 50% or more FC loss per day in a hot spa.  For bather load, the ozonator roughly cuts the requires oxidizer demand in half.  I don't know how the ozone is getting mixed into the water, but faster gas to water transfer would occur by increasing surface area so creating many tiny injected bubbles (such as via a Mazzei Venturi injector).

See Chemistries of Ozone for Municipal Pool and Spa Water Treatment for more detailed info on ozone.

[clover]

I have seen numerous reports,.....having an ozonator on vs. off, that show significant changes in chlorine demand under conditions of no bather load vs. bather load that are consistent with ozone being in the water..... 

Chem Geek, you raise a very good point, as both, Chlorine and ozone, are oxidizers / sanitizers, this would seem to indicate the ozone molecules are eliminating a percentage of the chlorine molecules introduced into the water, while the reverse action is also occurring, as ozone molecules are being reduced by the presence and interaction of the chlorine molecule.  It’s kind of like fish food in the water, as one sanitizer consumes the other in the absence of other matter in the water.  They both do the same job leading to different water management techniques. 

Chemicals are consumed daily, and require repurchase, while the ozonator's production of ozone molecules is diminished over time eventually leading to replacement, or reverting to chemicals, still with ongoing cost.

They both work well, but perform differently.  My personal choice is ozone, supported by decades of happy and satisfied customers who choose to replace the ozonator when it eventually expires.  The primary reason stated, is the ozone takes care of the water without their daily, weekly, or monthly attention, as it is constantly being administered without them. 

Believe me, when it is not working, they know it, and they call.

[kurt6137]

I also own a hot springs with the ozone. I am a little concerned now, but I am pretty sure the ozonator is off, when the jets are on. I never thought about that in making my purchase and I am usually very detailed. Makes me wonder now, I would have to see a scientific study on bathers in hot tubs with ozone, but you have got me thinking now.

[chem geek]

Ozone by itself is risky because you don't want it in the bulk spa water in any great amount because the outgassing is harmful and if you don't get enough into the spa water then it won't kill what can grow on spa surfaces (that obviously doesn't get circulated) and usually it's not on 24/7.  We've had reports from spa owners who didn't use chlorine but had ozonators and their water went south.  There are only four EPA-approved disinfectants for spas: chlorine, bromine, Nature²/MPS, Baquacil/biguanide/PHMB.  Ozone is not one of them -- ozone is for supplemental oxidation only, not for use as a primary disinfectant.

[clover]

I do not disagree with Chem Geek, you are unable to test for the presence of ozone in the water, while chemicals can be tested for, and this is the basic premise why ozone is not verifiable.  Additionally, there are many cases where consumers use chemicals exclusively, and their water can go south as well.  We all know there are reasons that need to be understood, before judgments can be made.

This is kind of like global warming, based on a lot of scientific theory, some of which is not verifiable, causing debate over the entire concept.  Its purpose is to change the way we live today, and generate global tax revenue for political purposes.  Now we have Kurt concerned about something he did not evaluate in depth prior to his purchase raising levels of concern to him.

We have all heard the disclaimers that says, "Don’t try this at home", when people who know what they are doing, as they do what they warn you not to do.

Ozone has proven to be an efficient and effective sanitizer/oxidizer, and reasonable measures have been taken by the industry manufactures to adapt it to be well suited to the water products they manufacturer.  If there were verifiable adverse reactions from the use of ozone, the products would not carry the various seals of approval, and product liability insurance would be astronomical.  All of these debates allow us to express what we know individually, and they are always challenged by the opposing point of view.  Again, something like global warning debates.  There is no end.

Let us assume, all of the fact previously stated are correct, Ozone needs to be injected, mixed, and fused in suspension with the water to extend hang time for its less than 30 seconds of existence.  If that is in the plumbing for a period of time, where most of the interaction takes place, it doesn’t really leave much time to break the surface of the water going airborne, which it certainly can do, as well as chemicals.  Both ozone and chemicals cause reactions to occur, and they dissipate as well..

We are creating fear and apprehension in the minds of others, when ozone is perfectly acceptable as a water management tool.  You just need to learn how to use the tools, starting with a test strip for pH and alkalinity.  Those who know and understand the use of ozone can then help others apply it.  If you are a naysayer, and do not believe in the effectiveness of ozone, then you shouldn’t sell it, or deliver it on a product you sell.  That would be hypocrisy, and your customer would be getting the short end of the stick.