This article first appeared on Mashable for a US readership and has been tailored for the UK audience.
Smartphones are quite unclean. You may have come across comparisons to toilet seats: The typical phone is said to be seven to 10 times more polluted than most restrooms, depending on the source, and one in six allegedly has traces of faecal matter. If you’re checking your phone as frequently as many, about once every 10 minutes, that’s quite a bit of exposure to a host of dirt and germs.
Brands like Apple suggest using a soft, lint-free cloth, a touch of warm soapy water, and a bit of rubbing alcohol to clean your phone. However, cleaning any electronic device must be done with care: Too much moisture can harm the device if it seeps into a port or crack. There’s also the possibility of damaging the screen’s protective coating, making it more susceptible to smudges and fingerprints.
Furthermore, keep in mind that there’s really no way to ensure you’ve cleaned every area when you quickly wipe down your phone — those germs could still be lingering while you text, chat, and watch TikTok. Surely, there must be a better solution, right? That’s the fundamental concept behind ultraviolet (UV) phone sanitizers.
What is a UV phone sanitiser?
Devices that use UV light to eliminate pathogens and superbugs have existed in the medical domain for many years, but consumer-friendly versions are a more recent innovation that have surged in popularity during COVID-19.
A UV phone sanitiser is basically a compact plastic or metal box fitted with a couple of UV bulbs or lamps, which illuminate your device during the cleaning process. Apart from avoiding moisture, fumes, and residues, the biggest advantage is the convenience: You simply place your phone in the sanitiser’s chamber, close the lid, and allow it to function for about five to 10 minutes. For optimal results, ensure you remove your device from its case before sanitising — you can clean that separately.
How does UV light kill germs?
UV light is a type of electromagnetic radiation commonly associated with sunlight, although it can also be replicated using artificial lighting. There are three categories of UV rays:
UV-A rays are the longest in wavelength. They can be found in tanning beds, bug zappers, and the blacklights at local clubs.
UV-B rays possess slightly shorter wavelengths. These assist skin in producing Vitamin D3 (but can also lead to sunburn) and are primarily utilized in tanning beds alongside UV-A rays.
UV-C rays have the shortest wavelengths. These are generally employed for disinfection, as they can damage the DNA of microbes. This either kills them or inhibits their function and reproduction.
Note: All references to UV light henceforth pertain specifically to UV-C rays.
Is UV light dangerous?
While UV light poses more of a threat to microbes than to humans, the U.S. Food and Drug Administration advises caution: “Direct exposure of skin and eyes to UV-C radiation from certain UVC lamps may result in painful eye injuries and skin reactions similar to burns. Never look directly at a UVC lamp source, even momentarily.”
The FDA also mentions that UV light can deteriorate plastics and polymers, but don’t worry: You would need hours of constant exposure to inflict any significant damage to your phone.
Do UV phone sanitisers really work?
PCMag has already delved into this subject comprehensively, which you can explore here. (For full transparency: PCMag is owned by Mashable’s publisher, Ziff Davis.) We won’t reiterate everything, but the summary is this: Sort of.
While UV light is effective in eradicating and halting the spread of specific bacteria (such as E. coli and Salmonella), the types of UV sanitizers being marketed to consumers are considerably less powerful than those employed in medical facilities. Although most producers assert that their phone sanitizers are 99.99% effective against common germs, very few substantiate their claims with independent lab testing.