Hot Tub Ozone vs UV – Pros And Cons

Which is better ozone or UV?

Generally, when it comes to methods of sanitation for hot tubs, utilizing ozone is considered to be a better option when compared to using methods of UV sanitation. This conclusion is due largely to the fact that ozone is considered to be a stronger method of sanitation.

For instance, UV disinfects water by killing bacteria and other living organisms within it. However, ozone is more powerful than chlorine or other chemicals and works to eliminate any contaminants within the water. So, while UV simply gets rid of bacteria, ozone will remove bacteria, odors, oils, lotions, and other organic molecules as well.

This being said, using ozone can be a large time investment and requires maintenance routines outside of those utilized when using UV sanitation methods. Yet, the average user prefers ozone as it reduces the amount of chemicals needed, provides extremely clear water, and removes a plethora of potential contaminants while remaining fairly cost effective and easy to use. 

Do UV lights give off ozone?

All UV light in the range of 120 nm and 240 nm will create ozone from oxygen. However, it is important to note that every commercial UV light source will produce a range of UV light and therefore a range of ozone as well.

This ozone is created by the separation of oxygen molecules using the UV light. As a result oxygen molecules once existing as O2 are transformed into ozone molecules of 3 oxygen atoms (O3). However, this ozone has a short half-life and cannot be stored. As a result, the ozone quickly reverts back to its original oxygen state and does not linger in the air long. 

Do UV lights kill mold?

While too much UV light is known to be harmful, smaller doses can be effectively utilized to identify and kill bacteria and mold. Most commonly, it is used to kill mold in air conditioning systems.

UV light is effective at killing mold when used in short wavelength frequencies. When this is done, it becomes germicidal meaning it kills the germs that produce mold. Furthermore, the electromagnetic works as a disinfectant and penetrates through the mold bacteria.

When concentrated in a lamp, UV light targets a specific area working to eliminate mold particles and destroys the cells to an extent that they are no longer able to reproduce and create new mold. As a result, UV light is an effective method to quickly kill any existing mold and prevent new mold from occurring. 

How long does it take UV light to kill mold?

UV light is extremely effective at killing mold. However, the rate at which mold is completely destroyed depends on the amount present in a given area. For example, in order to kill mold, it must first be identified.

Then, the UV light should be placed about 2 inches from the mold. All other lights should then be turned off completely, and the UV light should be left on for 1 to 2 hours. Then, if not all of the infected area was exposed to the light, the light source should be moved and the process repeated.

Therefore, at best UV light can be used to eliminate mold in the span of 1 to 2 hours but can take a significantly larger amount of time if there is a large presence of mold in a wide ranging area. 


List PROS / CONS Between them

Pros of Ozone

  1. Ozone is all natural and completely safe for use. 
  2. Due to the lack of chemicals needed to maintain clean water when using ozone sanitation methods, it is generally a more cost-effective option. 
  3. Ozone is made on-site meaning that it requires no storage of dangerous or bulky materials in a household or storage space. 
  4. Ozone is the only item needed to maintain clean waters. 
  5. Ozone poses no risk of chemical buildup or residue left within a hot tub. 
  6. Ozone is an extremely effective disinfectant being more potent than its chlorine and bromine chemical counterparts. 

Pros of UV light

  1. UV light has the ability to trigger the production of vitamin D in our bodies. As a result, it helps to build strong bones and muscles while also helping to strengthen the immune system. 
  2. Being exposed to UV light is believed to reduce the risk of developing colon cancer. 
  3. UV light slows down the growth of skin cells which has a positive effect on skin conditions such as psoriasis by reducing symptoms. 
  4. UV light exposure may improve symptoms of Tuberculosis. 
  5. Exposure to UV light is known to improve one’s overall mood by increasing the body’s production of tryptamine hormones. 

Cons of Ozone

  1. The lifespan of ozone is very short. This means that it has to be frequently introduced to hot tubs in order to maintain proper levels of sanitation. 
  2. Ozone is extremely reactive and corrosive meaning that safety measures and precautions such as installing corrosive-resistant materials must be implemented in order to prevent any damage from occurring to a hot tub. 
  3. Ozone creates a large amount of water waste upon implementation. 
  4. If present at high levels, ozone can be dangerous to inhale causing chest pain, coughing, throat irritation, asthma reactions, and other similar symptoms. 
  5. The initial installation process of a ozone sanitized hot tub can be quite pricey and time consuming as users must ensure that all the water is drained and the hot tub is completely disinfected and rid of any existing germs or bacteria. 

Cons of UV light

  1. Exposure to high levels of UV light is known to cause cancer. 
  2. UV light can cause sunburn. 
  3. Exposure to UV light is believed to suppress one’s immune system. This reduces the body’s natural defenses to bacteria and pathogens making it much more likely one will become sick. 
  4. Exposure to UV light is also known to cause irritation and burning of the eyes, In fact, direct exposure for a lengthened amount of time may result in a condition called photokeratitis which is a burning of the eye tissue. 
  5. Exposure to UV light destroys collagen within the body. This results in a loss of elasticity in the skin and contributes to premature aging and wrinkles.
Emily Williams

Emily Williams

Emily is a passionate Hot Tubs researcher who loves writing about all things Hot Tubs! She has years of experience and a knack for simplifying complex concepts, these articles are here to answer all your burning questions in a simple and easy to read style.
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