UV-C technology’s wide-ranging applications are largely unknown to the general public. But that is likely to change soon. Because UV-C radiation could make a significant contribution to reducing the COVID-19 pandemic. After all, the invisible lifesaver has been effectively protecting people around the world from harmful pathogens for decades.

Here, we’ll explain how public health is maintained every day thanks to the disinfecting effect of UV-C lamps and how UV-C itself is Coronavirus’ worst enemy.

UV-C radiation, with a wavelength of between 205 and 280 nanometres, damages the DNA of bacteria and viruses so badly, that they are killed or rendered inactive. A UV-C lamp takes advantage of this effect and sterilises water, air and surfaces. Even Coronavirus can be rendered harmless with UV-C radiation. Incidentally, UV-C radiation itself is not visible.

Ultraviolet radiation, or UV radiation for short, owes its disinfecting properties to its short wavelength and the associated high energy. As a type of electromagnetic radiation, UV-C’s wavelength lies between 100 and 280 nanometres. Is therefore much shorter than the light we see – by comparison, this lies between 380 and 780 nanometres. If a UV-C lamp emits a wavelength of less than 280 nanometres, the radiation breaks down micro-organisms’ chemical bonds. The damage to their RNA or DNA means bacteria and viruses are unable to multiply. As a result, they are no longer infectious. The highest sterilisation levels are estimated to be at around 265 nanometres. And as the artificially-generated radiation does not occur naturally on Earth, pathogens are unable to develop to UV-C radiation. That’s why UV-C technology disinfects so effectively. Whether it’s fungi, bacteria or viruses; UV-C lamps render all kinds of pathogens inert in the shortest possible time – with no chemicals, residues or discolouration.

Pool and aquarium owners are familiar with UV-C lamps in their day to day lives as they are an ideal alternative to chlorine and traditional aquarium filters for disinfecting pools. What works on a small scale will also work on a large one. So UV-C technology is used in chemical-free wastewater treatment, for instance. In many developing countries, where accessible drinking water is heavily contaminated with microbes, UV-C water disinfection devices are used for water treatment. The main advantage: Such solutions are cost-effective and very easy to use. There is often no alternative to UV-C-based water disinfection devices, particularly in remote areas with very poor infrastructure.

UV-C technology is an indispensable part of everyday hospital life. UV-C technology is used successfully against microbes of any kind and significantly reduces the risk of infection – particularly with direct/indirect contact infections and cross-contamination. In particular, it is an important weapon in the fight against Methicillin-resistant Staphylococcus aureus (MRSA), which remains resistant to most antibiotics. MRSA is especially dangerous for people with weakened defences. It is therefore important to stop its spread in hospitals and medical facilities at an early stage.

UV-C lamps can not only be used to prevent infections in hospitals but also in our everyday lives. This is a fact that has become enormously important in the wake of the Corona pandemic. As part of a recent study , PD Dr Adalbert Krawczyk and Dr Christiane Heilingloh, members of the Clinic for Infectiology’s Medical Faculty at the University Medical Centre Essen (Universitätsklinikum Essen) have demonstrated the high efficacy of UV-C radiation against the SARS-CoV-2 virus.

There are many ways UV-C lamps can protect us against pathogen infection. Here are some examples:

• Air sterilisation: Airplanes, offices, restaurants: In enclosed rooms, the finest virus-laden particles, known as aerosols, play an important role in the transmission of SARS-CoV-2. Regularly disinfecting the air with UV-C lamps can therefore significantly reduce the risk of infection.
• Disinfection in public areas: In public spaces, in addition to droplets, direct/indirect contact is responsible for many infections. Lift buttons, escalator handrails and shopping trolley handles, for example, pose a high risk of infection. With its UV-C solutions, the German start-up UVIS aims to prevent infections in just these kinds of situations.
• Smartphone disinfection: We handle our smartphones several times a day. It will probably come as no surprise that the germ load of smartphones is many times higher than any other everyday object. Bespoke UV-C solutions to disinfect smartphones help to minimize the risk of infection. For example, the LEDVANCE UV-C Sterilisation BOX. This practical device disinfects smartphones in just a few minutes. What’s more, it can be used to disinfect numerous other everyday objects such as glasses or keys.

Of course, the use of disinfecting UV-C radiation is not limited to the recent Coronavirus. Flu viruses, which are also responsible for scores of deaths every year, can also be inactivated with the technology.

The COVID-19 pandemic has increasingly shone a spotlight on the importance of UV-C solutions to the wider public. It is clear that UV-C radiation makes SARS-CoV-2 viruses inert on surfaces and thus prevents their spread. Up to now, appropriate solutions have been used, especially in the field of disinfection. But UV-C radiation could soon play a much more active role in the fight against COVID-19.

Funded by the German Federal Ministry of Research, the “Advanced UV for life ” research consortium at the Charité Hospital in Berlin is currently investigating how irradiation using UV-C technology affects the skin and mucous membrane. The hope is that short-wave UV-C radiation could eventually be used to significantly reduce the viral concentration in the anterior nasal cavity and throat.

As valuable as UV-C devices are for humanity, caution is always required in their use. As they can damage the skin and eyes, they should never be used directly on the body.

The LEDVANCE UV-C Sterilisation BOX is therefore equipped with a built-in safety mechanism. When the box is opened, the UV-C radiation stops automatically, thereby preventing damage to the eyes and skin. Generally, the following rules apply to open UV-C devices:

• Only point UV-C lamps at the surface to be disinfected. It is essential to avoid radiation to the skin or eyes.
• Leave the room when using UV-C devices in an open environment.
• Switch off UV-C devices immediately after disinfection.
• Do not allow UV-C devices to get into the hands of children.

As a rule, UV-C technology for personal use should only be used in closed devices, so that the safety risks are correspondingly low when used correctly. Read the manufacturer's instructions carefully before use. Then the UV-C device will disinfect as if by magic.