Wyze Air Filter and UV

Was looking for info on the Wyze Air Purifier and if it can be affective against the Covid virus but did not find much here.
The filters out there that advertise effectiveness against Covid have a UV bulb which is proven technology that Wyze does not have. I’ve installed a UV bulb in my home air handler duct which is a great way to help prevent infections.
So I thought, why not rig up a little box on top of my Wyze Air Purifier and install a UV bulb in it instead of paying hundreds more for a UV filter…any thoughts on this?

Welcome to the community…

To be honest, after perusing some of the research (I don’t profess to be an expert), I personally am leaning toward the opinion that in general most of the air purifier UV devices sold to consumers is more of a marketing gimmick than doing anything effective. For example, consider the following:

researchers estimated that, when applied to current regulatory standards, far-UVC light could kill 99.9 percent of airborne coronaviruses in about 25 minutes. They believe that these findings would extend to SARS-CoV-2 as well.

25-minute exposure? That’s a long time…I am confident the air and virus circulates in and out of their machine much faster than 25 seconds, let alone 25 minutes.

Some do say 30 seconds:

looked at using a specific type of UVC light to kill SARS-CoV-2 on laboratory surfaces. The study found that the UVC light reduced the live coronavirus by 99.7 percent in 30 seconds.

But still, there’s no way it’s sitting still for 30 seconds before pushing that air back out. Which means, it’s probably not doing as much as those companies want us to believe.

study found that UVC light exposure completely inactivated the virus in 9 minutes

Some warnings I read about people considering using UV for Covid cleansing…

most types of UV light can be harmful to people. Exposure can result in skin irritation, damage, or burns.

So be careful how it is aimed if attempted. They recommend mostly using it for disinfecting surfaces, not the air where humans are currently actively present. Here is a what they said Hospitals use to disinfect the air:

hospitals use a UVC-emitting robot that’s about the size of a dorm room refrigerator to sterilize entire rooms…Once people leave the room, the device gets to work emitting UV rays, self-adjusting to the size of the room and variables (i.e. shadows, hard-to-reach places) to administer the light for as long as it deems necessary. This could 4-5 minutes for smaller rooms such as bathrooms or 15-25 minutes for larger rooms, according to Tru-D, one type of this device. (FWIW, this is done in tandem with manual cleaning using EPA-approved disinfectants.)

So even with a super refrigerator-sized professional UV machine, it still takes 4-5 minutes to clean a small bathroom, or 25 minutes for more patient-sized rooms. So, a little consumer UV air filter that has a virus go through it and back out with less than a second of exposure? I have my doubts about the effectiveness. I guess this researcher sums it up pretty well:

“Most home UV light disinfection devices that we have examined and tested [through our research at the University of New Hampshire] do not achieve the levels of germ-killing that they claim in their advertisements. Most are under-powered, poorly designed, and might claim to kill 99.9 percent of germs, but when we test them they often achieve less than a 50 percent kill of germs.” [Note: not necessarily Covid either]

Barty agrees, saying that the devices do in fact emit UVC, but “not enough to really do anything in the amount of time claimed.” Remember, for UV light to really kill germs, it needs to be shining for a certain period of time and at a certain wavelength — and, when it comes to effectively killing COVID-19, both of these measurements are still TBD, according to the FDA.

Anyway, I’d recommend not even bothering with UV, but that’s just my opinion. We are much better off focussing on filtering out the viruses which is proven to be effective. According to the EPA:

In order for an air cleaner to be effective in removing viruses from the air, it must be able to remove small airborne particles (in the size range of 0.1-1 um).

OK, so what about Wyze’s filters? Wyze’s standard Filter is HEPA 13 (Considered Medical Grade). This means it filters out 99.95% of all particles as small as 0.1 microns (um) in size. Therefore it’s perfect based on what the EPA says you need. The other 2 filters are HEPA 12 which means they can trap 99.5% of 0.1um, so they’re still great too.

If you’re worried about cleaning the air that you are present in, then focus more on the filter than the UV…the UV air purifiers are somewhat misleading and a lot of independent researchers that test them say their claims are not accurate. UV does have a scientific basis, but not in the context they’ve implemented it.

But again, just my thoughts on the matter and why I don’t worry about UV for air (it is much more effective for killing surface gerns, like shining it slowly over a counter-top or putting your phone in one, or whatever). To each their own. In full-disclosure I have 3 Wyze Air Purifiers using the HEPA 13 filter.

4 Likes

:clap::clap: Wow! You did a lot of research for that answer! Great information, I didn’t know any of that before!

1 Like

Yes wow, thank you for the detailed response. I’m an engineer and really appreciate the data, awesome! I have spoken with a business who claims to have positive real life experience with UV in AC vs years with it. However, they purchased a high end system compared to my $100 amazon bulb. So no way for me to prove it is working which is frustrating.
At the very least you convinced me to get the Wyze Air Purifier for when my kids go back to school (aka the germ factory). Thanks again.

3 Likes

Don’t take anyone’s word about UVC here, look it up yourself on reperable sources. People quote stuff all the time doesn’t mean it’s actual fact. And I’m not saying what was quoted above isn’t scientific fact, just saying don’t rely on anything from a forum, do your own research.