How UV Technology is Used to Prevent the Spread of Viruses

Everybody on the planet knows by now that viruses can spread in several ways. The main path of transmission is person-to-person contact via droplets and aerosols, which are emitted when an infected person talks, sings, coughs, or even breaths. Viruses can also be transmitted when people touch their faces right after touching surfaces that have been contaminated by infected individuals. This is a huge concern in healthcare facilities, retail spaces where people frequently merchandise, and all kinds of public transportation. 

What is Ultraviolet Light?

The definition of light is that it is a form of energy that travels in rhythmic waves. The distance between two waves is called the wavelength. Electromagnetic radiation is the type of radiation that includes radio waves, visible light, and X-rays. These are most commonly measured in nanometers. Light wavelengths that consist between 100 and 400 nm are considered ultraviolet (UV), which lies just beyond the violet part of the visible light spectrum, which means they are invisible to the human eye. Ultraviolet light waves are divided into the UV-A, UV-B, and UV-C regions. Respectively their wavelengths are 315-400 nanometers, 280-315 nanometers, and 200-280 nanometers. 

Why is UV Effective in Killing Viruses?

UV light particles called photons between 200 and 300 nanometers are absorbed quite efficiently by the nucleic acids that build DNA and RNA and besides that, photons below 240 nanometers are very well absorbed by proteins. These essential biomolecules are being damaged by the absorbed energy from the photons, destroying the genetic material inside a virus or any other microorganism, turning them unable to replicate or cause an infection, thus inactivating the pathogen. It typically takes a low dose of UV light to inactivate a pathogen. The dose is determined by two factors – the intensity of the light source and duration of exposure to the light. For a given required dose, lower intensity sources require longer exposure times, while higher intensity sources require shorter exposure times.

Use of UV Lights in Disinfection Technologies

The market for UV disinfection devices has been already established, and it has found use in many different fields. Germicidal ultraviolet technology has been in use for about 100 years now and has had success. Hospitals have been using devices that emit UV light for years for disinfection of the patient rooms, surfaces, operating rooms, and other areas where bacterial infection can be spread. Goes the same for the dentist’s offices. It is probably something that you have seen at the dentist’s, attached to a ceiling, but had no idea what it is used for. They usually turn the UV light on when they are done for a day and leave them doing their job over the night. There are even robots made that emit UV-C and can enter empty rooms and roam around remotely emitting high-power UV irradiation, and that way disinfect surfaces. 

A Modern Approach to UV Technologies 

Regarding the unlucky situation in the world this year, UV technologies and their use in the disinfection of objects and surfaces are getting more and more attention. UV is being tested for its use in disinfecting buses, trains, planes, and pretty much everything. However, the main focus is on using this type of technology to provide modern solutions to prevent HAI transmission, especially considering how hospitals might be a susceptible source of virus spread. It is even possible to use UV to disinfect the air, as well as the parts of our clothing which can spread the virus almost unnoticed, like our shoes for example.

Is UV Safe for Humans?

Everything that was said about the efficiency of the use of UV light as the universal disinfection system is making us all think, how great and simple this idea sounds, and why aren’t we using it more. That raises another concern – how does it affect humans? If it’s that easily lethal for viruses, how safe is it for us to even be exposed to it, and for how long? As mentioned above, as the wavelength decreases, the ability of the photons to get into the skin decreases. The top skin layer absorbs these shorter-wavelength photons, which results in minimizing DNA damage to the active skin cells which are present in the deeper layers of the skin. Theoretically, it works something like that, but in real life, eye safety and long-term exposure have not been well studied yet, and these types of devices surely need to be validated for effectiveness before being used in public settings

Even though the more specific testings on the modern technology of this kind have not been conducted yet, it is possible that trusted and validated UV light systems installed in public places could help control virus transmission and other potential viral pathogens, today and in the future.