Bryan is joined by his sister in law Shaunda to demonstrate a UV light and Petri Dish Demo.
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All right, so this quick video is just a test that I wanted to do and there's a couple different angles on it. One is is that some people will say that UV doesn't do anything which I don't believe at all. I think that UV has been demonstrated. Uvc specifically, has been demonstrated to be effective against living organisms like bacteria and fungus, as well as viruses that contain genetic material.
They have been shown to be effective to deactivate that genetic material. So what we did was take some of this agar gel and we put it into a petri dish. This is sort of a standard thing that you can do in a customer's house to demonstrate what's in their air now it doesn't show specifically what it is. It's not a real test, but it does show whether or not there is something growing in their air.
So you take this dish, you pour the agar and you leave the dish open for five minutes and you close it tape. It shut and wait five days to see what grows, but what we did instead was. We did two of them. We took one that we did the normal way and we did another one and we ran this little very inexpensive, it's about as cheap as you get UV one.
That's powered with USB. It's very low-power, a 3 watt power consumption and it shows a intensity of 120 micro watts at 2 to 5 centimetres. So this is very low power, and so I thought well, you know 20 seconds. That's a decent amount of time.
Let's just see if it has an impact, so this is the test that we did. You can see. We poured them both in as actually my sister-in-law Shonda doing it at her house and did the test sealed him up. I brought him back out and you can actually see that there is a difference between the two.
The UV clearly had an effect on the one that that was shown on the issue with UV, isn't that it doesn't work. It's that there is a level of intensity and a level of dwell time required in order to have the desired effect and, depending on specifically what type of live organism that it's hitting. There are different deactivation times. So it's not to say that UV doesn't work.
It does work on surfaces where there is more dwell time. We know that when you shine a UV, see lamp close to an evaporator coil, it has an effect on that of a protocol. The question is more, so what does it do on the air around? So again, point of this is just to kind of introduce you to this idea of using a total count, agar gel and a petri dish, and also the show that a UV light does have some impact on, and actually you know enough that you can. You can see the difference.
Okay, so here's a quick petri dish demo with one UV light and one non UV light. It's the same solution in both of these basically just a host we're gon na. Let it sit for five minutes and on the Left, we're gon na take the UV light and hover it over for roughly 20 seconds covering them both up gon na tape, the side, so no new air particles can get in there and then store it in a Drawer for about five days and check back on it so exactly five days later, this is what it looks like. The left is the UV and the right is non-treated. Definitely some more growth there. This was done in a home with no indoor air quality products. If you do try this, I recommend not taking the lid off because it smells rancid. I don't know exactly what you get from that, but hopefully you found it interesting, we'll catch you in the next one.
Where do you get the solution from?
You not even suppose to be exposed to these uv at all Are you in Barrhaven ?
There are a lot of cheap USB powered UVC lamps you can buy off Amazon that don't do anything. So be aware if you're buying a hand held device.
The rgf Halo is a fantastic device I personally have the iwave-r in my house I would like to have the rgf Halo in there. I have put those basic Honeywell UV lights in air handlers above the coil and the mold that was growing on the slant coil was dead the next year and her air handler looked almost brand-new .
I love this test. However, I think another test I would like to see is the growth from before and after a UVC light installed in an airhandler
Thank You Service area Orleans??
Interestingly, UV light was both shown to be effective on airborne infectious organisms in the 1930s, but the same experiment proved infections spread via the airborne route. However, since the 1930s, the official recognition was of only the large droplets we've heard so much about recently and long-range airborne nuclei, such as happens with measles. This current virus has force the grudging recognition by the CDC and WHO of close-range aerosol transmission in indoor areas, with prolonged exposure, but no transmission at a distance or apparently via HVAC ducting (likely due to dilution) in non-healthcare settings.
I found this survey on UV disinfection of air from 2010:
" In 1935, using aerosolized B. coli, 254 nm radiation, and carefully controlled conditions, Wells went on to demonstrate that airborne infectious organisms could be effectively killed in a short period of time.42 The use of UVGI not only inactivated the infectious organisms in the air, but proved the very concept that infections can be spread via the airborne route. Sharp was the first to confirm these results and documented an example of airstream disinfection, foreshadowing the use of UVGI in in-duct HVAC systems"
Reed NG. The history of ultraviolet germicidal irradiation for air disinfection. Public Health Rep. 2010;125(1):15‐27. doi:10.1177/003335491012500105
Pretty cool and simple test
Now everybody wants to pretend what they've used for years is not true anymore so they can still be buddies with their friends in the media😒.
Definitely informative as always
Don't remove the lid!!!
Exactly..if the extended duct is long enough, a 'GAUNLET' of Uv c can be constructed with no shadows at a pressure drop to slow the air passing (dwell, or exposure time) and transition back into a duct to re establish velocity for delivery.. consider a tube and shell configuration. If uv C can fry flesh, I am sure it can sterilize viral cells..
Thank you for bringing this back..my 40 watt uv c 198nm lamp burns over my a coil 27/7. annual if not sooner tube changes to maintain 100 % power of the lamp. 👍🏼 Service area Nepean??
Good stuff
Awesome explanation and demonstration of what uv can do.