Can 253.7 and similar wavelengths go through glass? Is it safe to view a UVC bulb through a 1/4 piece of glass?
No expert here, but NO. Polycarbonate safety glasses are recommended for blocking some wavelengths. But this is something that needs research or a knowledgeable member speaking up. But please be safe.
I found this on the internet, cant find it discussed commonly
Use of safety goggles and gloves is recommended as a precaution during installation to protect the eyes and skin. UVC light cannot pass through glass. There is no harm to look through an air handling unit access window at UVC lighting.Apr
This topic is way over my head. UV light from the sun, UV from various applications, there are variables. If no one answers, you might post a thread with a title like UVC protection or something and include the range and power of your situation, just to insure your eyes are safe. But I do not know what I am talking about here.
thru quarts glass yes, regular glass not really, or you would be getting suntan behind windows, polycarbonate will stop anything below 400nm. acrylic 375nm
I was under the impression simple polycarbonate was not effective for 365nm, which contradicts your post.
And regular glass definitely lets UV pass, you can easily suntan behind windows.
what about this for things like phone and keys and headphones so I don’t have keep wiping them with lysol things.
Astrolux® MF01 Mini UVC Disinfection Flashlight 99.9% Sterilization Rate Phone Face Mask UV LED Sterilizer UVC Germicidal Light - Black
look if you turbo direct fet that boi it’ll die in mere seconds
Suntan is done by UVA, in tanning salons the tubes emit only UVA
The get protection from sunburns the skin needs to be exposed by UVB, so even with tanning salons brown skin you can easily get a sunburn
UVC is the evil radiation that ionizes and let DNA decay damaging the skin very badly, UVB or UVA also does it but a lot less
I find it terrifying that UV-C flashlights are or were offered. Hope those are only fake.
i doubt that battery power puts enough light power out, to do anything, including damage to human skin or corona-stuff
A battery powered UV-C LED can cause enough damage to your skin and eyes.
ok
i guess it helps me that i have never seen one
A “germicidal bulb” (fluorescent tube minus the phosphor coating) is way way more cost-efficient.
That big bulb in the sky 
probably kills a lot of virus cells, but it won’t fit in a holster let alone a pocket.