Disinfection with UV light

Dangerous germs are everywhere. UV light inactivates them. How? The Heraeus Blog tells you more

An incredible number of viruses, bacteria and other dangerous germs colonize doorknobs, faucets and also the air. They easily get into the mouth via the hands or are simply inhaled. Many viruses, such as the SARS-CoV-2 virus, are mainly transmitted via aerosols. The risk of infection is therefore high when many people are in close proximity to each other and the air cannot be exchanged well.

UVC light helps to clean the air and surfaces.

Read more about scientific findings, trends, new products and exciting application examples here.

UV light is an effective weapon against viruses

UV light is an effective weapon against viruses

UV light in the range between about 200 to 280 nm wavelength, more precisely UVC light, is very effective against viruses, bacteria and fungi.

The UV light easily penetrates the envelope of the viruses and hits the genetic material inside. There it causes dimer formation, which prevents the virus from replicating. UVC light inactivates viruses immediately and permanently, they are no longer infectious.

How effective is UV light against viruses, bacteria and germs?

Independent studies have demonstrated the effectiveness of UV-C radiation in inactivating SARS-CoV-2 (coronavirus).

UV light destroys dangerous germs, this has been confirmed in many tests and studies. UV light is able to inactivate microorganisms up to 99.9999%, which corresponds to a reduction of Log 6.

This property has been used for decades in the treatment of drinking water. UV disinfection is also used in food packaging, making dairy products or bread last longer.

Since the beginning of the Corona pandemic, many independent studies have demonstrated the effectiveness of UV-C radiation in inactivating SARS-CoV-2 (coronavirus). UV disinfection is reliably effective on surfaces and in air.

Devices for UV disinfection of surfaces and of air were tested. Surrogate viruses and real coronaviruses were used. It was repeatedly demonstrated that viruses were reliably inactivated even at high air flow rates. For the first time, tests were carried out under real conditions in a classroom: UV-C light can reduce viruses by up to 99%.

UV light inactivates them all - whether coronaviruses or flu viruses

UV light inactivates them all - whether coronaviruses or flu viruses

UV light inactivates the RNA or DNA of dangerous germs. It does not matter to the UV light whether a virus is called corona or omicron - or flu or cold. They all have genetic information and this is inactivated.

The effective and reliable effect of UV disinfection makes it sustainable.

Germs cannot develop resistances. Mutated viruses are inactivated just like the original germ.

UV air purifiers are thus an efficient additional protection against flu and cold waves even without a pandemic.

Why air filters with UV light instead of HEPA filters?

Filters that remove hazardous substances from the air already exist. They are proven for filtering pollen or dust particles and thus help allergy sufferers. Virus filters, however, have higher requirements. In order for filters to really get viruses out of the air, they must be so-called HEPA (High Efficient Particulate Air) filters.

Air filters suck in the room air and get the viruses out. The cleaned air then flows back into the room. What is the difference between UV and HEPA?

HEPA air filter

In HEPA filters, the trapped viruses are collected in the filter. When the filter is full, it must be replaced. Otherwise, the device can no longer collect viruses.

Filters must be changed regularly. This is expensive.

Air filter with UV light

A UV air purifier inactivates the passing viruses. The UV light acts on the genetic information of the virus. As a result, the virus is no longer infectious.

This works over and over again as long as the UV lamp stays on. And UV lamps are very long-lasting.

Why Indoor Air Quality (IAQ) is a key component for healthy buildings

Air purification with UVGI is important for IAQ

Building owners, property managers and facility managers want to ensure they provide healthy buildings that protect and even improve the wellbeing of occupants. In the past this focused primarily on interior design elements such as sound dampening, space planning, colors and furniture, as well as creating outdoor spaces. However, following the COVID-19 pandemic and the knowledge that the virus spreads from person to person primarily through the air, there is a new focus on improving indoor air quality (IAQ).

IAQ addresses unpleasant odors, harmful particles, such as allergens and dust, and especially now, airborne viruses. Studies show that poor IAQ reduces productivity and learning, and can cause headaches, fatigue, and enable airborne virus transmission. As many property managers discovered, increasing outdoor air in an effort to reduce virus spread significantly increases energy costs.

Most existing commercial building HVAC systems include particulate air filtration. Some facility managers upgraded these particulate filters to higher MERV ratings or even HEPA grade filters to catch airborne COVID pathogens. However, the fan capacity in many HVAC systems often prevents using a particulate filter effective against viruses. A more effective and efficient solution that doesn’t impact fan capacity is to install UVC direct airstream disinfection devices. Using either in-duct or in-room UVC, also referred to as germicidal (UVGI), devices can dramatically reduce the germ load in a building or room to ensure the wellbeing of occupants.