Saturday, 26 August 2017


( not is this pool, but seen in some pools in India)

UV-C light is a very powerful germicide. It deactivates and renders harmless waterborne pathogens that are completely unaffected by chlorine based disinfectants. Examples of dangerous pathogens (viruses and cysts) neutralized by UV-C light are Cryptosporidium parvum and Giardia lamblia; chlorine will not affect these.
UV-C is effective against all microorganisms for example also the Pseudomonas, papillomavirus and e-coli.

UV-C cannot, however, be used on its own. This is because after the pool water has been subjected to treatment with UV-C, it is disinfected but not disinfectant. A secondary disinfectant must be added to the water to ensure that the water actually in the pool is disinfectant as well as disinfected. The most commonly used secondary disinfectants are chlorine based chemicals.

Is the smell of pool water changes by using UV?
Yes, the smell of pool water changes. This is because of the lack of chloramines in the pool, UV-C kills destroys the chloramines.

As a by-product of the disinfection process (as mentioned in the question above), chlorine combines with bathers’ body fluids in the pool water to form chloramines. Chloramines are unpleasant substances that cause eye, skin and nose irritation, breathing difficulties in young children, an unpleasant swimming pool “chlorine” smell and last but not least, damage to the fabric of the pool such as tiles, grouts, handrails and other fittings.

UV light is destroys chloramines, thus reducing or even practically eliminating the undesirable side effects mentioned above of the use of chlorine based disinfectants.
VGE’s UV-C ranges offer the solutions mentioned above.

Because of the UV-C which disinfects the water, you don’t need chlorine to disinfect the water, you only need chlorines to make it disinfectant. This makes sure you are able to decrease the amount of chlorine to a max of 80% (depending on de type of pool).

Chlorine increases the PH value, Less chlorine means less increase of PH. This means you also need less PH or another acid.
Less acid makes sure the bicarbonate level is longer stable and needs less corrections.
When it’s a saltwaterpool, less Chlorine means less salt. You also need less shock.

UV-C kills the bad chloramines, this means you’ll need to do less maintenance to the pool due to chloramines. This decreases the maintenance costs.

What are the microorganisms it tackled by this UV?
Uv-C is effective against all microorganisms.

Is any microorganisms survive after this UV treatment.
No, when the right amount of UV and wave-length is used, no micro-organism will survive. The swimmers will be protected against diseases caused by micro-organism who are resistant of chlorine.

Do you need to select the UV unit equivalent to the flow of filter? ( e.g., what is best UV required for filter pump flow of 125 cu mtr /hr?)
The right UV-unit depends on different factors. For example the flow, T10, total water volume, temperature and amount of people swimming in it.
Can you please send me the T10 and water volume (95%? Normal pool water)? Then we’re able to calculate the right equipment for you.

Is there any ratio allowed to reduce the size of UV to be economical?
The economical comparison of the various solutions depends very much on pool size, design and usage.

Please also see my answers above for the economic benefits and UV-treatment. You can reduce the amount of UV, for example when the pool is for a while not in use.