UVC lamps against corona - disinfection with ultraviolet radiation

Ultraviolet (UV) light has been used for years in various fields for physical disinfection. The UV light damages the nucleic acids (DNA) of bacteria, viruses and other microorganisms during irradiation.

The effect depends on the wavelength, the duration of irradiation and the distance from the radiation source to the irradiated surface. Due to the global pandemic caused by the coronavirus, interest in UV disinfection is increasing strongly and the demand for its use in hospitals, doctors' offices, nursing homes, etc. is significantly higher. Disinfection by UV light is an effective method by killing coronaviruses and other pathogens in addition to surface cleaning and chemical disinfection.

SHOULD UV RADIATION BE USED FOR DISINFECTION?

Ultraviolet light is a form of light invisible to the human eye that exists in the electromagnetic spectrum between X-rays and visible light. We are exposed to a small amount of ultraviolet light from the sun's rays every day, although much of it is absorbed by the ozone layer. Ultraviolet radiation is divided into three wavelength ranges: 

• UV-A: wavelength range 400-315 nm 
• UV-B: wavelength range 315-280 nm 
• UV-C: wavelength range 280-100 nm 


At a wavelength of approx. 265 nm, bacteria, viruses and other microorganisms are particularly severely damaged. The UV-C radiation causes irreparable destruction of the DNA, so that replication and thus reproduction of the pathogen cannot occur.

WHAT ARE THE AREAS OF APPLICATION? 

UV light has been used for disinfection for a long time. Be it in food production, in storage rooms, in waste water and drinking water treatment or in the pharmaceutical industry. In hospitals and medical practices, permanently installed UV lamps are used for disinfecting storage rooms or in ventilation systems for air disinfection. Meanwhile, UV disinfection is increasingly used in the form of mobile systems for room disinfection. The areas of application for this are diverse and flexible: fitness studios, hospitals, hotels, retirement and nursing homes, offices, elevators, rehabilitation centers, shopping malls, showrooms - basically in all places where people meet.

IS THERE ALREADY APPLICATION IN OTHER COUNTRIES?

In addition to the global application in the areas of food production, drinking water treatment and the pharmaceutical industry, the interest of the healthcare system in UV systems for disinfection has increased. In many countries, currently especially in China, Italy and the USA, disinfection with UV-C light is increasingly used. Due to the corona crisis, mobile disinfection units and robots that independently disinfect treatment and patient rooms, operating rooms and laboratories with UV-C light are being used, especially in hospitals.

WHAT IS THE EFFECTIVENESS AND WHAT ARE THE DANGERS OF UV LIGHT?

Several studies have shown that UV-C radiation inactivates 99,99 % (e.g. 2016 Cambridge University Study) of vegetative bacteria (MRSA) and viruses (SARS-CoV) on the directly irradiated surface as well as behind objects after only 3-15 minutes.

After 50 minutes of irradiation, even spores of C. difficile (one of the most common hospital germs) were eliminated. In addition to the surfaces, the room air is also disinfected, so that a UV-C system can close disinfection gaps that remain after wipe cleaning and chemical disinfection.


When used correctly, UV-C radiation is not harmful to humans. It does not penetrate into deeper skin layers and is almost completely absorbed by horny skin already at the surface. The possible clouding of the cornea in the human eye can be prevented by wearing simple protective goggles. In the case of direct skin contact, sunscreen with a high sun protection factor prevents possible sunburn. In addition, UV-C radiation does not penetrate materials such as plastics or glass and is therefore harmless to people outside the room.

CONCLUSIONS:

Ultraviolet light to kill viruses, bacteria and fungi is already the tool of choice in the food industry. Although the technology has been around for decades, it has not yet been able to establish itself outside of industrial applications. Thanks to autonomous robots, however, the solution is now also finding its way into hygienic building cleaning.

The JKS HERO21 is a disinfection robot developed in partnership with both OMRON and ICA. It achieves a disinfection level of 99.99 percent with 360-degree coverage. The robot moves autonomously through the rooms to be disinfected. Once the device is turned on, it can be remotely moved into the contaminated rooms via app. The HERO21 scans all room data and stores it. Its special sensor system detects whether a person is still in the room. If this is the case, the robot does not activate, but sends a danger message.

The HERO21 is funded by the German Federal Ministry for Economic Affairs and Energy through a resolution of the German Bundestag and has been nominated for the 2020 FOCUS Innovation Award.

SEE THE HERO21 LIVE IN ACTION?