Understanding how UVc works....
***SEE UPDATE BELOW***<br />Original review - 9/13/14 - I've just ordered (3) of these units from Amazon for my own home so can't speak for the build quality of these units (yet), but work with UVc enough in large-scale commercial applications to know how the process works.<br /><br />UVc works by converting some Oxygen (O2) molecules into Ozone (O3).  Ozone has a very short life span, quickly reverting back to O2 when it comes into contact with a contaminant, but yet is also nature's most effective sanitizer. The process to create ozone is the same as you experience in lightning storms with the crisp smell when electricity is applied to the surrounding air.<br /><br />Ozone removes odors very effectively but neutralizing the containment through oxidation. In addition, oxidation also kills many bacterias and some viruses not just in the air but any surfaces the treated air comes in contact with. It's like bleach but without the chemical smells and dangerous spills. This is why hospitals like this technology so much. The point to remember is ozone does NOT remove particles in the air, but those particles certainly are clean ones.<br /><br />The low fan speed being reported is due the fact that applying an electrical charge to oxygen atoms takes some time, relatively speaking. You can't do this with a high volume of air across a single bulb thus the need for a slower speed of air movement. But the low speed air that does come out, will surely cleanse the air and surfaces it comes in contact with. This is also why this likely will only work in a small room or area (less than 500sqft I would guess). You would need more/larger bulbs with larger surfaces areas exposed in the air chamber to do larger volumes of air.<br /><br />The UV-C light works in the 185nm and/or 254nm wavelength and is harmful if exposed, which is why the bulbs are sealed from direct view. Seriously, don't open the unit up and try to get it to work "better". There likely are safeguards to prevent this.<br /><br />I'll follow up this review once I've had a chance to use the units myself.<br /><br />**UPDATE - 10/2/2014**<br />I bought (3) and returned (2) after trying these units out (I never opened the other 2). I've also downgraded to 3 stars from 5 for the following reasons:<br />- Yes, this unit is loud. I tried it in kitchen and the hard surfaces (granite) just seemed to project the fan noise throughout the house. I've since demoted this to bathroom and it's still very loud even with door closed.<br />- Having tried it in kitchen and bath, it doesn't seem very effective. I found no discernible difference in letting this unit work versus time taken through natural dissipation of cooking/odors<br />- As mentioned in my original review, ozone is what removes odors through the use of UVc light. I see the product description and the packaging mention this unit produces no ozone. A quick visit to the manufacturer's website says the UVc light penetrates thin-walled viruses and bacteria altering the DNA. I can't speak for this method, so I have to assume the time exposed and the power generating the UVc light isn't sufficient enough to create the ozone. I see this as a reduction in effectiveness compared to my experiences with commercial applications of UVc. Granted, you don't want accumulated quantities of ozone confined in an indoor space and this product prevents that.
Rating: 3 stars