years ago I already had a large HEPA filter and a negative ionizer in the room. Back then these technologies were all separate machines, while today they are UV air purifiers that include HEPA and up to ten technologies.
What Exactly is UV?
If you’re wondering what UV light is the clue is the word “violet” in “ultraviolet”. UV light comes from the location of the violet rays in the visible color spectrum.
Back in 1877 two scientists from England, W. Hugo Downes and Thomas Blunt, discovered that direct sunlight can kill bacteria. They found this when doing an experiment in which sugarwater in the sun remained clear while shaded sugarwater became cloudy with bacteria. Years later Marshall Ward discovered it was the violet light spectrum that had the bacteria-killing properties. In 1903 Niels Finsen was awarded the Nobel Prize for Medicine for his work using UV to kill TB (Tuberculosis). UV is nothing new.
Given the problems with new forms and strains of germs, viruses and bacteria in the world UV has become more important than ever. And it’s been nice to see companies like Oreck, Alen, and Alive Air and others integrate UV light into their Air Purifiers. As I mentioned before in the 1960’s I had separate machines for UV, Negative IOn, HEPA, Carbon, etc. It’s really been in the last 10 years that more manufacturers incorporated UV along with HEPA.
Problems With UV in Air Purifiers
Several problems in the industry I have seen when it comes to UV air Purifiers include the following:
1) Price – UV bulbs are very inexpensive to produce, yet some manufacturers charge 40-100 for a small UV bulb (see the comparison chart page for prices). UV bulbs should not cost more than 24-30 max.
2) Deception -The Oreck Helioshield Air Purifier model claims that “You never have to change the UV bulb”. But call an Oreck store and you find out that it has to be changed every 9 months to be effective. What they really meant to say is (according to a store I called) “Only a Oreck Dealer can change the bulbs in order not to void the warranty. they wouldn’t quote me ma price over the phone.
3) Fan Speed – If the fan speed is too high the air will likely go over the bulb without killing germs or viruses effectively in many UV air purifiers. The way around that is by the use of Tio2, a nanotechnology grid which (when UV light shines on it) magnifies the UV spectrum up to 1000x. Look for Tio2 if you get UV.
Should You Include UV?
The benefits of UV air purifiers include:
#1 By killing germs UV air purifiers can help reduce colds and flus from spreading in your home
#2 By sanitizing the air UV light can prevent mold, bacteria, and mildew from spreading
#3 By giving the immune system a rest at night it will be better prepared to handle threats during the day
#4 Even pets will benefit from being in a UV treated environment, preventing bacteria from pet dishes and bowls
For these reasons above I encourage people to add UV into their air purifier. Even if their problem is allergies, which is best served by a HEPA filter, killing germs and bacteria can provide added support for an immune system which is prone to react to pollen and dust.