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Do UV light devices kill COVID-19? Here’s what experts say
By Lisa Prevost
August 9, 2020
Salons, hotels, and even public transit are investing in devices that emit ultraviolet light to protect against the coronavirus, but some gadgets work better than others, and experts warn UV isn’t the magic bullet many hope it is.
Ultraviolet light can burn the skin and damage the eyes, but studies show it can also kill COVID-19 in the air and on surfaces, given enough time, according to the University of Pennsylvania.
There’s no evidence to show, however, that UV does anything to prevent infection, or can destroy the virus in an already infected person, according to the University of Pennsylvania.
The germ-killing form of electromagnetic radiation is being offered in plenty of different packages, big and small, including handheld wands, overhead lamps, UV-based air filtration systems, phone cleaners that look like tiny tanning beds, and more.
Upon reopening, a La Jolla, California salon installed three air-purifying UV systems, Fox 5 reported. “My thought is we can’t get shut down again,” Janie Snyder, a hairstylist with the salon told Fox 5. “So, we’ll do anything possible to make everything as safe as possible.”
New York’s Metropolitan Transit Authority is testing UV’s potential as well, The Verge reported, cleansing the city’s subway system using lamps and 150 “mobile devices,” as part of a pilot program launched in May.
Those with deeper pockets are taking it a few steps further. The Beverly Hilton Hotel in California now has a three-foot tall robot named Kennedy that goes into unoccupied rooms shooting UV at all visible surfaces, ABC News reported.
It retails at $125,000, according to the manufacturer.
UV HAS LONG HISTORY AS DISINFECTANT
Robotic hotel maids may be a fairly 21st century development, but ultraviolet’s impact on a host of bacteria and viruses is well established.
“UV light disinfection has been around about 100 years,” James Malley, professor of civil and environmental engineer at the University of New Hampshire, told the outlet. “Done well, it can be a great tool in the toolbox, because it’s an extremely rapid physical disinfectant that is chemical free and it literally works at the speed of light.”
But with so many UV-related products on the market amid pandemic, much of what’s available is ineffective or unproven.
“The safety and efficacy of many UV light devices sold to the public are not routinely reviewed, so these should be used with caution,” the University of Pennsylvania warns.
Illuminating Engineering Society, an industry trade group, spoke out on the issue to CNN.
“Ultraviolet disinfecting ‘wands’ or other ultraviolet products for residential use — as they are inadequately proven and unregulated — may pose a safety hazard and are unlikely to provide the protection expected,” the group said in a statement sent to CNN.
It’s important to note that it takes time for ultraviolet light to kill COVID- 19, and until those particles are destroyed, they’re capable of infecting.
MASKS, SOCIAL DISTANCE TOP TOOLS
Xenex Disinfection Services, the manufacturer of the “LightStrike” cleaning robot in use by the Beverly Hilton Hotel, says the machine eradicates more than 99% of the virus in 2 minutes at a distance of about 3 feet, a claim verified through testing by the Texas Biomedical Research Center.
And a recent study measuring the effects of sunlight on coronavirus spread found that it takes approximately 34 minutes of exposure to summertime sunlight to inactivate 90% of the virus, McClatchy News reported.
Still, social distancing and face masks likely remain the most valuable tools for avoiding person-to-person spread, especially indoors and in crowds, Cory Merow, co-author of “Seasonality and Uncertainty in COVID- 19 Growth Rates,” told The New York Times.
“If everybody sits next to one another on the bus and coughs,” he said, “ultraviolet light is not going to protect you.”