Can UV sterilizer lamps for a pond make a constant noise (hum)? What are "high frequency" UV lights?

[omega3]

Hi,

We are thinking about getting a UV light sterilizer for our pond in the garden. Dimension of the pond are 9m x 1,5m x 1,5m = 20.25 m³ = 20250 litres in metric which I believe is around 5350 US liquid gallons. I'm from Europe and used to the metric system so my apologies if the gallons are incorrect.

From what I've read we would need a 40 to 60 Watt UV light sterilizer, which apperently is placed next to the pond (so not submerged inside it).

My main question is if those UV sterilizer lamps can make any (low or high frequency) constant noise/hum and if so, how far away can you hear that noise?

That pond in the back garden is fairly close to our house so will we hear it in house (in our bedroom) and in the garden? Since an UV sterilizer works 24/7 so also during the night, we obviously don't want to hear any noise from those UV lamps in our bedroom. So do these lamps make any noise/hum and how far away can you hear that?

Second, does anybody know what "high frequency" UV C lamps are? Does "high frequency" mean that those lamps emit a high pitched sound or does it mean something different?

Thanks in advance for all good feedback on this.

 

[herm0016]

very unlikely that anything electronic like that will make so much noise you can hear it through an exterior wall. Its just going to be the power supply like most electronic things.

 

[Micrornd]

My experience with UV Sterilization is on citie's size scale units. But maybe some on that is relevant.

While the electronic drivers can make noise, that is easily solved by putting them in a sound deadened housing.

Your water will need to be pumped over the UV emitter(s) by a submersible pump.
Submersible is a better choice than above ground in this application and cheaper also.
Any noise the UV element makes (a slight humming is not unusual) is negated by the UV element being surrounded by the water in it's housing.

UV emitter life is not only based on runtime, but much more deleterious is the on/off cycles.
(Larger UV emitters are actually "ramped on" and "ramped off" to extend (virtually quadruple) their life compared to abrupt on/off)

All UV emitters used for water sterilization are UVC (short wavelength UV).
This is because most living "things" have no natural defense for UVC since they aren't naturally exposed to it.
(The sun produces UVA, UVB and UVC, but while UVA and UVB penetrate our atmosphere, UVC is reflected by the ozone layer, hence the big fuss about that layer and it's possible shrinkage)

You also want to remember that UV sterilization is based on contact time (flow rate over the UV emitter), turbidity (cloudiness of the water).
The longer the water is in contact with the UV emitter the better, the clearer (less cloudy) the water is the better.
Both of these can significantly reduce (or even prevent) the sterilization of the water.
Normally this type of UV sterilization is after the filter system used in the aeration of the pond for maximum effectiveness.
If your supplier doesn't discuss the above with you, I'd look elsewhere to purchase the equipment.

Disclaimer -
Please remember, while UVC is has not been shown to be harmful to human skin (as in causing cancer as UVA and UVB have), it has been found to cause damage to human eyes (as does UVA and UVB) on a long term basis.
UVC is also generated when ARC welding, hence the polarizing and filtration lenses used there.
So avoid looking at or staring at the UV emitter, just for long term health safety.
And those UV blocking glasses or lens treatments on the market, well unless they specifically have an EPA or UL seal and say they block UVC, then they don't.

TLDR - Probably way more then you wanted.