UV-C Lighting Is A Technology Whose Time Has Come
Signify is expanding its UV lighting offering. It is increasing its UV-C lighting capacity eight-fold and recently announced 12 new families of products and systems aimed at professional markets. But what exactly is UV lighting, how does it work and where can it be applied?
First, some science. UV light is that part of the electromagnetic spectrum that spans 100-400 nanometers (nm). Basically, it is divided into three different types, A, B and C. UV-A and UV-B is found in sunlight. It’s what gives you a suntan or sunburn. UV-B is well known for medical applications such as the treatment of psoriasis and is also responsible for the formation of bone-strengthening vitamin D.
Then there’s UV-C, which is an invisible light, spanning the range of 100-280 nm, and has powerful germicidal properties.
“When designed properly, installed correctly with safety instructions followed, is a safe and highly effective form of disinfection”
UV-C from the sunlight is filtered out by the Earth’s atmosphere. We should be thankful for this as exposure to certain wavelengths of UV-C radiation is hazardous to the skin and eyes of humans and animals. Despite this, UV-C lighting, when designed properly, installed correctly with safety instructions followed, is a safe and highly effective form of disinfection.
Proven Track Record
Signify has been involved in UV-C lighting for more than 35 years. Their conventional Philips UV-C lamps have the same familiar shape as our well-known fluorescent tubes. Their peak wavelength of 254 nm is close to the 260-265 nm germicidal peak and proven to be extremely effective in breaking down the DNA (and RNA) of bacteria, viruses, fungi and mold spores, rendering them inactive and harmless.
For years, UV-C has been used to disinfect drinking water, wastewater, air, pharmaceutical products, and surfaces against a whole suite of pathogens. In fact, it has rendered inactive all bacteria and viruses tested to date (many hundreds over the years including coronaviruses).
Disinfection of surfaces is performed through direct exposure to the UV-C radiation from lamps, luminaires or disinfection carts that are activated when people are not present. They can be brought into a workplace or bus or train when people have left. An extra level of safety may be provided by remote on-off switches and sensors which can shutdown systems if people or animals are detected.
Typical surface disinfection lamps are 55W and depending on the dose, disinfection can be done in seconds or a matter of minutes.
Signify also offers a range upper-room air disinfection systems thanks to its recent acquisition of the assets of Germicidal Lamps & Applications (GLA). Its ceiling-mounted units rely on natural or mechanical ventilation in the room. Contaminated air, at an upper level, passes through a ‘UV-zone’ where it’s disinfected. Such systems can be used in rooms with people present as the light source is shielded from those below and located at a height of at least 2.3m.
Signify cut its UV-C teeth in providing lamps for water disinfection. They are used all over the world in both water treatment plants and residential drinking water purification systems. Applications include disinfecting and purifying drinking water, wastewater, process water, swimming pools, and ponds. UV-C lamps are available in wattages from 4W up to 1000W depending on the application, which varies from large municipal installations in which several hundred lamps are used to small units that fit inside household sinks to disinfect drinking water. These domestic units are popular in India and China.
UV-C Lighting To Fight Germs
Going forward, the applications for UV-C are as huge as they are diverse. Let’s take a look at just one market, supermarkets.
Research has proven that shopping trolleys can harbor 361 times more bacteria than a bathroom doorknob, while supermarket fridge doors can have 1,235 times more bacteria than the surface of your cell phone.
As shoppers browse the aisles, air disinfection systems can eradicate tiny airborne droplets, while lights fitted under check-out conveyer belts can disinfect them and remove unpleasant odors. And after closing, luminaire systems or wheelable carts could disinfect the store’s surfaces, whilst special UV-C tunnels disinfect shopping trolleys.
Today, companies and institutions are waking up to a new normal where germ and virus-free spaces are no longer ‘nice to haves’. UV-C lighting, which has been around for more than 40 years, is a well-tested, yet relatively unsung technology. It has taken a terrible pandemic for it to emerge out of the shadows. A technology whose time has surely come.