How UV-C light is fighting COVID-19
What is it, how is it being used, and how reliable is it in the fight against coronavirus?
Before the pandemic stuck a great big spanner in the proverbial works, terms like ‘social distancing’, ‘shielding’ and ‘quarantine’ were either unheard of or confined to the pages of a dystopian novel. Well, we can add UV-C light to that list of things most of us have never heard of but are suddenly very important now.
Here’s a brief lowdown on UV-C light and how some companies are harnessing its power to make the world a safer place.
What is it?
To start with, you’ve more than likely heard of UV — or ultraviolet — light. It’s the slightly eerie purple glow you see in crime scene investigation shows that reveals blood stains. If you’re a keen sunbather, you’ll also be aware of the harmful effects of ultraviolet on the skin.
Sunlight contains three types of UV light. First, there’s UV-A, which makes up the vast majority of the ultraviolet radiation reaching the Earth’s surface. It can penetrate deep into the skin and is thought to be responsible for up to 80% of skin ageing. Powerful stuff, but nothing most humans are not used to.
Next there’s UV-B, which is strong enough to damage the DNA in our skin. Persistent exposure to UV-B radiation can cause skin cancer, but it can be largely blocked out by most sun creams.
Then we come to UV-C, the third and most harmful type of UV radiation. UV-C is capable of destroying genetic material and would — if you excuse the graphic imagery — fry our fragile skin if we were exposed to it. Luckily for us, we don’t have to be; the vast majority of UV-C rays are absorbed by the Earth’s ozone layer.
So, how is it used?
Because of the dangers, humans steered well clear of UV-C light for decades. But that all changed in 1878 when scientists discovered that they could harness UV-C to kill microorganisms. Today, UV-C has become a staple method of sterilisation – one used in hospitals, airplanes, offices, and factories every day. It’s also a crucial element of the water sanitisation process.
Using UV-C light to combat viruses is considered highly effective, but only when applied correctly. At the right dosage, the radiation warps the structure of their genetic material and prevents the viral particles from making more copies of themselves. It’s led to some of the biggest companies in the world investing in UV-C technology.
Signify, the global leader in lighting technology, has released a range of products designed for sterilising air, surfaces and water. Their lamps and luminaires are already being used in hospitals, supermarkets, hotels, and other high-risk public areas.
One example is the UV-C disinfection batten range, released by Signify under its Philips brand. These luminaires can be mounted on walls, ceilings or disinfection chambers, and they can inactivate 99% of viruses that pass under them — a figure validated by tests carried out at Boston University. Popular uses so far have been disinfecting shopping trolleys, mobile phones and even medical equipment, as these kind of surfaces are hotbeds for viruses, bacteria and germs.
OK, it can kill viruses, but what about COVID-19?
Scientists have always been certain that UV-C light is effective against pretty much every virus known to man, but up until recently, the results on whether it can inactivate COVID-19 were inconclusive. That was until studies at Columbia University in the US confirmed what everyone had been hoping for: UV-C light is effective against the SARS-CoV-2 virus that causes COVID-19.
Despite the study being in its relatively early stages, the results are encouraging. They will no doubt spark a clamour as companies race to develop their own solutions for battling COVID-19 and play their part in getting the global economy back up and running.
Check out how some of the Point 6 team have coped during lockdown!