UV lamps and COVID-19
Can UV lamps kill the COVID-19 coronavirus? After some research that the coronavirus cannot live long in the sunlight people started wondering whether UV lights can help in disinfecting indoor spaces and even people themselves.
The idea that you can disinfect your skin, clothing or other objects with UV light has proved extremely popular .
There’s only one type of UV that can reliably inactivate Covid-19 – and it’s extremely dangerous, comments for BBC Dan Arnold from UV Light Technology. The company provides disinfecting equipment to hospitals, pharmaceutical companies and food manufacturers across the UK.
In the global anxiety about Covid-19 situation, Dan Arnold has recently received some unusual requests as that to install UV light lamp on the exit to the supermarket
You would literally be frying people,” comments Dan Arnold, in disbelief.
Three types of UV rays
Sunlight contains three types of UV. UVA is capable of penetrating deep into the skin and is thought to be responsible for up to 80% of skin ageing. The UVB can damage the DNA in our skin, leading to sunburn and eventually skin cancer. Both can be blocked out by most good sun creams.
There is also a third type of rays: UVC. They consist of a shorter, more energetic wavelength of light that is very good at destroying genetic material – whether in humans or viral particles. It’s filtered out by ozone in the atmosphere long before it reaches our fragile skin.
Artificially produced UVC
In 1878 scientists discovered that they could harness UVC to kill microorganisms. Since then artificially produced UVC has become a staple method of sterilisation – one used in hospitals, airplanes, offices, and factories every day. Crucially, it’s also fundamental to the process of sanitising drinking water; some parasites are resistant to chemical disinfectants such as chlorine, so it provides a failsafe.
In a recent study which looked at whether UVC could be used to disinfect PPE – the authors found that, while it is possible to kill the virus this way, in one experiment it needed the highest exposure out of hundreds of viruses that have been looked at so far. The amount of ultraviolet required varied widely, depending on factors such as the shape and type of material the virus was on.
UVC to disinfect buses and money
Nevertheless, a concentrated form of UVC is now on the front line in the fight against Covid-19. Buses in China are being didinfected each night by the ghostly blue light each night, while UVC-emitting robots have been cleaning floors in hospitals. Banks have even been using the light to disinfect their money.
UVC - efficient but dangerous for people
But for people UVC can be really dangerous. “You shouldn't be exposed to it,” comments Arnold. It canburn your skin and eyes in secondsq warns he.
To use UVC safely, you need specialist equipment and training. The World Health Organization (WHO) has issued a stern warning against people using UV light to sterilise their hands or any other part of their skin.
Recently, scientists have discovered a promising new type of UVC which is less dangerous to handle, and still lethal to viruses and bacteria, BBC reports. Far-UVC has a shorter wavelength than regular UVC, and so far, experiments with human skin cells in the lab have shown that it doesn’t damage their DNA (more research is needed to be sure).
"It has been used for quite a while in surface decontamination by bringing very bright lights into, say, the hospital room between patients to do a quick surface decontamination. But that means having lights so bright you can't have people in the room because it will hurt their eyes", explains to CNN prof. Donald Milton, at his laboratory at the University of Maryland, US.
Despite all the dangers for people the has increased offers to sell people ultraviolet decontamination lights for offices and even homes. These rods won’t kill germs immediately, warned the Illuminating Engineering Society, a non-profit industry group.
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.
The group says that lamps installed in ceilings at least 7 feet high can safely decontaminate air, but also warns that the light can irritate people's eyes. "Germicidal UV is also being applied for disinfection of some personal protective equipment (PPE) for limited reuse during the pandemic," the group added.