How long does it take a UV light to kill bacteria?
A UVC light is very commonly used in a woodshop or metal shop eye protection
cabinet. It's also used in certain air conditioner air purifiers. The time of exposure to UVC depends upon the size of the bulbs. The ones in the school cabinet recommend 15 minutes. The ones that I made by taking two 30 watt bulbs 3 ft long using an ordinary fluorescent fixture with an electronic ballast puts out a total of 60 watts of type-c shortwave radiation. I wanted to see if I could use the light to give me a suntan! I wore suntan goggles and stood in front of that contraption for 1 minute. I didn't think one minute would even make my skin the slightest bit tan! But the next day I was red as a lobster from head to toe! Worst sunburn I had ever gotten in my life. Yes type c ultraviolet can destroy your eyes and burn the crap out of your skin in record time. Don't put one of my room sterilizing homemade lights in a room with a fish tank or a canary or a dog or a cat or a person or a plant it'll kill it dead as doornail. My 60-watt contraption well sterilize the crap out of your bedroom in about an hour. It's excellent to have one of these contraptions made up for when you have a cold or the flu. Or just keep your room healthful let the thing go off 1 hour a day by a timer when you're not there. And your entire room will smell Sunshine fresh.
By now, you may already know that there is UV-A, UV-B, and UV-C light. For years, hospitals and laboratories have used UVC Test Cards to determine how long it takes their high powered UVC lights to kill bacteria and viruses on surfaces and tools of the trade. The UVC Test Card is much easier than calculating the mathematical formula that depends on the size of the light, how many watts, and the distance away from the surface. The UVC lights sold online are not trustworthy of producing proper “Germicidal UVC exposure. if any at all” And if you decide to buy one online? But remember, unless you’ve tested the lamp with the proper device, such as a simple UVC Test Card yourself, there is really no way of knowing for sure if it will kill viruses and bacteria. For me, I am so happy I tested my device. I never really felt that relaxed and assured feeling, using and trusting something i bought online, until I tested it myself. The first little white UVC phone sanitizer box was fake and I was seriously mad! But my other UVC light actually worked properly. And after seeing it work properly with my own eyes, I felt a weight of worry lift off me. Now I feel really good using it every day and it’s one less thing I have to worry about. SInce one hospital grade UVC Test Card is relatively cheap (UVCTestCard dot com), I truly feel everyone who buys a UVC Germicidal light should test it.