Hospitals have embraced ultraviolet (UV) lights as a cleaning tool for many years, utilizing large, and industrial-grade equipment to decontaminate rooms. Now, smaller versions of UV sanitation lights are available to customers looking to clean pretty much anything, from phones to toilet seats.
The three major types of UV rays are UVC, UVA, and UVB. Since UVC rays have the shortest wavelength and the highest energy, they are capable of destroying bacteria and viruses, also known as pathogens. UVC light has a wavelength of about 200 and 400 nanometers (nm). It is highly effective at decontamination since it destroys the molecular bonds that hold together the DNA of viruses and bacteria, as well as “superbugs,” which have developed a stronger resistance to antibiotics.
Powerful UVC light has been frequently used to decontaminate surgical tools and hospital rooms. Research that included 21,000 patients who stayed overnight in a room where someone had been previously treated found that sanitizing a hospital room with UV light and conventional cleaning methods cut transmission of drug-resistant bacteria by 30%. This is partial because UVC light can effectively sanitize hard-to-clean nooks and crannies. UVC light also works by removing the DNA of pathogens, making it effective against “superbugs.”
But this broad-spectrum light is also a health hazard associated with diseases like skin cancer and cataracts — and humans cannot be in the room when employed. Recently, nevertheless, researchers have been working with narrow-spectrum UVC rays (207-222 nm). This kind of UVC light kills bacteria and viruses without penetrating the outermost cell layer of human skin.
A 2017 study indicated that 222 nm UVC light destroyed methicillin-resistant Staphylococcus aureus (MRSA) bacteria just as effectively as a 254 nm UVC light, which would be toxic to humans. This research was repeated in 2018 on the H1N1 virus, and narrow-spectrum UVC light was again found to be effective at eliminating the virus. This has a particularly important effect on public health since the possibility of non-toxic overhead UV lighting in public spaces could drastically reduce the transmission of diseases.
Destroying bacteria and viruses with UV light is particularly effective since it kills germs irrespective of drug resistance and without toxic chemicals. It is also effective against all viruses, even newly-emerging pathogen strains.
How to Employ a UV Light to Kill Germs at Home
UVC lights available to consumers come in various forms, as well as boxes, bottles, and covered wands. Each has its own set of instructions for how to employ the light to kill germs, with specifics on things like how long the sanitation takes and, in the case of wands, how close it has to be to the object are attempting to sanitize. Larger box-shaped versions fit, baby bottles, and toys.
One 2008 study tested the efficacy of the VIOlight, a toothbrush sanitizer that claims to rid your toothbrush of disease-forming germs. The research found that, compared to a toothbrush that had not been treated with ultraviolet light, the VIOlight got rid of 86% more colony-forming units of S. salivarius, lactobacilli, and E. coli. These bacteria can result in strep throat, digestive problems, and many other illnesses.
Sanitizing wands enables you to wave UVC light over anything you might want to disinfect, as well as counters, bedding, and steering wheels. The wands can be employed anywhere, claim to work within seconds, and are often marketed to travelers concerned about things such as hotel room sanitation. A 2014 research tested the efficacy of these portable wands and found that they destroyed 100% of commonly-found bacteria within five seconds and inactivated 90% of spore-forming bacteria, which are harder to kill, within 40 seconds.
Besides surfaces, UVC light can purify water, too — when employed properly. Companies that sell UVC pen-like devices and UVC bottles claim to eliminate 99.99% of bacteria and viruses from water. Such products are usually valuable to hikers and travelers to remote areas, both of whom more commonly encounter unpurified water sources.
A 2015 research in Travel Medicine and Infectious Disease looked precisely at a handheld UVC light device called SteriPEN. The researchers established that the number of bacteria and virus reduction depended on how the device was employed.