We use UV lights to sanitize medical equipment already. I’ve heard of some offices implementing some UV solutions for cleaning desks and other office surfaces, but nothing new since. Why aren’t we using it in more places? It seems to me to be a cost effective, chemical free, generally *easy* way to disinfect surfaces and objects.
Some examples I thought of would be inside of a refrigerator. These can be full of germs if not properly and regularly cleaned (which many people don’t do) so why not have a UV bulb in there that turns on for a few seconds after the doors close? Or even a cycle that can be scheduled to run each night?
Another would be under cabinet lights in a kitchen. Kitchen counters can be notorious bacteria breeding grounds (the vast majority of food poising cases come from within your own home after all) so why not have some UV light strips underneath that could annihilate all the bacteria automatically?
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UV light can cause burns and skin cancer. It distrupts all sorts of cells, both those of germs and those of our bodies. Large doses of UV light should only be used in human-free areas or in controlled environment by specialists. I remember one case when unattended UV light source at hospital caused heavy burns to someone (they didn’t see device was working – it did not emit visible light).
UV light kills bacteria etc by essentially blasting it with light until it breaks apart.
To do this, you need the UV light to be of sufficient intensity and duration to kill the bacteria. That means that all surfaces of the object to be sanitized need to be in direct, intense light for a period of time.
The kind of intensity required to sanitize a kitchen counter from cabinet height would be cost-prohibitive at best and likely to blind you at worst.
It would have to be a very bright bulb, in terms of UV. A [tanning bed](https://www.familyleisuremedia.com/images/detailed/11/Tanning-Bed-Systems-18-Select-24724.jpg) damages *some* of your skin cells over a period of a few hours. By contrast “disinfection” is defined as killing 99.9% (1000) cells per 10 minutes, and “sterilization” as killing 1 million – 1 billion cells per 10 – 30 minutes. The light bulb would have to be super-bright to accomplish this.
UV also doesn’t “penetrate” too deeply past the first layer of cells, so it’s effective for disinfecting a flat surface for example, but it will NOT disinfect a “blob” of bio-material (a droplet of yogurt for example) because it doesn’t penetrate.
And finally, the biggest issue with UV is that [UV light degrades plastics](https://www.essentracomponents.com/en-us/news/product-resources/uv-and-its-effect-on-plastics-an-overview), and we have A LOT of plastics in our daily objects, including the interior of the refrigerator.
Left out in the sun, plastics yellow out due to the UV from the sun, and eventually become brittle and flake out / break apart / decompose into base chemicals. The effect would be even more pronounced at the UV levels required for disinfection, and you’d have to have special UV-resistant plastics not just in the fridge materials, but also in all the tupperware and food containers that are typically made of plastics. Because you don’t want chemicals from the plastics to be decomposed by the UV light and leach into your food.
‘New type of ultraviolet light’ kills 98% of airborne microbes in a room and could help prevent the next pandemic, scientists claim
https://www.dailymail.co.uk/sciencetech/article-10643177/New-type-UV-light-kills-98-microbes-room-help-prevent-pandemic.html
I think this explanation needs to be up a level, medical settings are really the only places that need to be sterile, sure you could sterilise every surface humans interact with, this might reduce issues short term but it will lead to an overall drop in peoples immunity to basic microbes.
The basic fact is that microbes in offices, homes, workplaces, shops etc don’t present a big risk so there’s very little reason to fight them.
>Kitchen counters can be notorious bacteria breeding grounds (the vast majority of food poising cases come from within your own home after all)
Not to mention, sure you just killed the bacteria, but the physical contamination remains. You still have a smear of chicken juice or whatever it might be on the counter that needs to be cleaned regardless.
I don’t know about the other reason, but it degrades banana faster, and that’s a no-no for me.
Search banana UV test.
I work in HVAC and install uv lights in furnaces. It’s generally viewed as a gimmick. Getting a high quality air filter and routinely changing it makes a bigger difference.
How often to change the filter depends on the home (smoking, animals, general cleaning upkeep, how often the furnace is used etc)
For work I operate Hydrogen Peroxide Vapor Decontamination equipment in hospitals. This system is advantageous due to the fact that it has almost 100% coverage. It can get inside and out, above and below most anything in the room as long as we have set up the room to maximize penetration. This in combination with the fact that it is safe for use with almost all electronics makes it highly effective. Cooling fans on a PC tower will actually draw the vapor inside the tower and sterilize the interior components. In addition, when optimized, HPV has a higher kill rate than UV and is uniform throughout the majority of the space. With UV, you have to worry about shadows, as well as beam degradation. Like any light, the further from the source you get, the weaker the beam concentration. UV seems like a great solution when high degrees of decontamination aren’t required. However, in a medical setting, there is practically zero margin for error when it comes to sterilization.
Special UV lights are available, but are currently cost prohibitive.
GE made them for surgery rooms, but COVID has presented a new opportunity for growth.. https://www.gecurrent.com/brands/365disinfx-disinfection-lighting
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