Frequently asked questions

Here you will find the answers to the most common questions asked.


Ultraviolet (UV) is electromagnetic radiation that is just outside the area of the light spectrum that is visible to the human eye.

UV-C treatment works in two ways:
1. UV-C lamps emit short-wave ultraviolet radiation (253.7 nm), neutralising bacteria, viruses and other primitive organisms and preventing them from reproducing. This works even if these organisms have become immune to other disinfection methods.
2. UV-C causes a photo-oxidation process that destroys chloramines without the addition of other chemicals. Chloramines are responsible for the unpleasant smell of the pool water and irritation of nose and throat.




•    It protects swimmers against diseases caused by micro-organisms (which are immune to chlorine).
•     It prevents irritation of eyes, nose, skin and airways caused by chloramines.
•     The addition of energy in the form of UV-C radiation means that free radicals are formed in the water. These radicals oxidise chloramines.
•     No unpleasant ‘swimming-pool smell’.
•    UV-C adds nothing to the pool water and so does not form any by-products.
•     UV-C works independently of pH value.
•     UV-C does not affect the pH value.
•     It may reduce the concentration of disinfectant in the pool.


Environmentally friendly
UV radiation is environmentally friendly and sterilises without the use of chemicals: toxic chemicals require specialised storage and handling. Since no chemicals are used, overdosing is not possible.
This technology has low initial investment costs and offers reduced operating costs.

Efficient and effective
UV radiation treats the water immediately and there is no need to have tanks or for long retention / lighting times.


UV radiation functions extremely well with other air and water processes, as no changes are made to the taste, smell, pH, conductivity or chemical properties of the air / water in which it is used.

Yes, every one of our units carries the CE mark. The associated declarations can be requested from your contact person. (In future: you can download / consult here)

The entire production process of our own-brand products (X-clear and Blue lagoon) takes place at our site in Son, the Netherlands. Our products therefore carry the label “made in the Netherlands”


Xclear pond uvc disinfection and filtersBlue Lagoon pool and uvc equipment


A ballast serves two purposes:

1: It provides sufficient voltage to break down the rare gas contained in the lamp
2: It limits the current flowing through the lamp

For some lamps the ballast also has to supply heat to the electrodes in the lamp as preheating.

VGE customers can report a complaint to their contact person by telephone or e-mail. The contact person will try to resolve the complaint by phone with you. If it proves necessary to examine a product further, your contact person will provide you with a complaint number that you can refer to on the complaint form to accompany the item to be returned. Return shipments without this RMA number will not be dealt with.

VGE International BV uses low-pressure UV-C lamps. The most effective way of producing UV-C energy is by using a low-pressure mercury arc, which excites the mercury atoms to a high energy level. After reverting to low energy consumption the atoms will radiate with a characteristic spectral line with a wavelength of 254 nm. By coincidence this wavelength is close to 265 nm, the wavelength that is most deadly to micro-organisms.

Standard low-pressure lamps
Applications with a relatively lower flow rate and the possibility of achieving a longer contact time.

Low-pressure HO lamps
Applications in which a higher flow rate and short contact time are needed, while retaining effectiveness.

Low-pressure amalgam lamps
Applications in which a wider ambient temperature plays a role or in which a higher intensity is required.

Germicidal UV-C systems work by irradiating running water using UV-C light. The lamps are fitted in a treatment chamber, which disinfects the water within a few seconds. A dose of 30 mJ/cm2 is more than enough to destroy most micro-organisms in the water.

Yes, chlorine or some other disinfectant continues to be needed even when UV-C is used. In a lower concentration, but it is still necessary. Though UV-C disinfects it is not a disinfectant (it adds nothing to the water).


Pool water is treated on average just once every 4 hours.  When the water comes out of the UV unit it has been disinfected but does not undergo any further treatment. The water will again become infected in the pool, so the protection will disappear. To prevent this from happening, the continuous presence of a disinfectant (such as chlorine) is necessary in the pool.






Standard low pressure UV-C lamps

For applications with a relatively low flowrate and possibility to realise a longer contact time.


Low pressure HO UV-C lamps

For applications where a high flowrate and short contact time is necessary with retention of efficacy.


Low pressure Amalgam UV-C lamps

For applications where a wide environmental temprature is of influence or where a high intensity is needed.


Generally speaking, UV-C lamps should be replaced once a year.


The average effective life of a UV-C lamp is 9,000 hours (13,000 hours for amalgam lamps). Although the lamp will still continue to work after this period, its disinfecting value will rapidly declline from then on.

The average effective life of a UV-C lamp is 9,000 hours (13,000 hours for amalgam lamps). Although the lamp will still continue to work after the end of this effective life, its disinfecting value will rapidly declline from then on.

Yes, UV-C lamps operating at 254 nm can effectively break down ozone.

Is your question not answered above?

Of course we are very happy to help you.