UVC light disinfection is a form of sterilisation that can successfully inactivate all known microorganisms. For nearly 100 years, UVC disinfection has evidenced it’s capabilities to be an effective killer of germs and viruses and be a very useful tool in fighting the spread of infections. As the pressures on longterm, sustainable ways of hygienic living continue, UVC disinfection offers a solution which takes reliance away from chemical or water based sterilisation methods, as well as other throw-away resources. The Covid-19 pandemic has naturally accelerated the level of technology and use of UVC light and how it can play a part in protecting us now and in the future. This article explores some of the science behind UVC disinfection and why your business should consider swapping to it!
How does UVC light disinfect?
The way UVC light disinfects is by “agitating” microorganisms. When UVC light comes into contact with a microorganism, the light penetrates through their cell wall and this causes an agitation to the Uracil or Thymine, depending on whether the microogainsm is a RNA or DNA structure. This agitation provokes a change to the molecular structure and this change inactivates the pathogen and stops it from multiplying and causing infection. UVC Light forms part of the ultraviolet light spectrum and can be used as a method of disinfection. Ultraviolet light (UV light) comes in three separate forms;
Name Wavelength
- UV A (315-399nm)
- UV B (280-314nm)
- UV C (100-279nm)
UVA and UVB light is what we are all familiar with as this is what is emitted from the Sun. UVC light incidentally is also emitted from the Sun, but is blocked out by the Earth’s ozone layer. As a result, the UVC wavelengths, also known as UVGI (ultraviolet germicidal irradiation) that are produced are “man-made” and designed to achieve disinfection outcomes
Within the spectral range of UVC light, there is an optimal disinfection curve relating to the wavelength. The optimal wavelengths are between 240 - 280nm, with most UVC bulbs generating wavelengths of 254nm. UVC LEDs emit wavelengths within the range of 260-280nm, and are also extremely effective at disinfecting.
How UVC light affects DNA What does it disinfect?
UVC light is laboratory proven to successfully inactive all known microorganisms. Each microorganism comes with it’s own rate of resistance, and part of the challenge of disinfecting bacteria and viruses with UVC light is understanding the microorganism in question to then create a sufficient UVC dosage required to inactivate it. Not only do the rates of resistance vary across microorganisms, but their resistance also varies if you are trying to inactive the pathogen on surfaces, in the air or in water. Typically, the easiest location to disinfect bacteria and virus is in the air, because there are less other molecules.
One of the biggest questions is whether UVC light can be used to kill Covid-19 (SARS-CoV-2). The answer is yes. The SARS-CoV-2 virus is extremely susceptible to UVC disinfection as well as other historic coronaviruses. The BBC discusses how this is possible here!
Not only does UVC disinfection inactive all microoginisms, but as a result this reduces the risks of transmission amongst people. For example, in the 1950’s, the use of UVC air disinfection helped reduced transmission of the Influenza pandemic in Asia.
How long for?
The process of UVC disinfection can happen in a matter of seconds. Studies have shown that a 99% disinfection rate of SARS-CoV-2 virus can be achieved in just a few seconds.
UVC surface disinfection is calculated by looking at the proximity of a UVC bulb, the power of that bulb and how long that bulb is disinfecting for. As a result, the longer the bulb is disinfecting for, the greater percentage of microorganisms you will inactivate.
When looking at UVC air disinfection, you are considering other factors such as the volume of air in a room and it’s level of movement. This is known as the Fluence rate. UVC air disinfection works in two ways. One, by sucking air into a closed unit, treating the air with UVC light then pushing out disinfected air. Or two, by having a partially open unit, typically installed in the upper areas of a room, that can UVC can travel through and inactive the pathogens in the air.
Our Philips UV-C air disinfection technology has been proven to inactivate 99.99% of SARS-COV-2, in the air of a room within 10 minutes. At 20 minutes, the virus was below detectable levels.
How do I know it's working safely?
There are lots of different product mechanisms which help show you that the UVC disinfection process is working. Even though UVC light is invisible, a purple glow is typically added so you can visibly see that the UVC disinfection is in process. In units with the UVC bulbs are enclosed, then a notifying signal on the product is provided to tell you that the UVC process is in action.
Like all wavelengths of UVC light, too much exposure can be harmful to humans. As a result, each UVC disinfection product by regulation comes with multiple safety features. Whether this be motion detecting radar, alarms, timers, child-locks or anti-gravity sensors. When UVC units are being installed, part of the responsibility of the provider is to ensure there is sufficient safeguarding in place and that the units are fit for purpose.
Not only have all of Dakro’s products gone through certification testing to scientifically prove the bacteria and virus killing rates, but you can easily test whether your UVC disinfection unit is working. From a surface disinfection point of view, we can place ‘dosage meters’ under the UVC bulbs and leave for a period of time. We can then obtain a reading to establish the UVC dosage that the bulbs are generating.
For testing UVC air disinfection, you can measure the air quality of a space. By treating the air with UVC light, you are improving the air quality by disinfecting the airborne pathogens. You can see the dramatic differences in air quality before and after using UVC within a room.
Why is it useful for businesses?
The biggest asset of any business is their staff. By keeping your staff healthy and protected, you in turn create a safer place to work and help reduce sickness in your workplace. In the UK, employees lose an average of 30.4 working days a year due to sickness or absenteeism. By having UVC technology proven to inactive airborne pathogens, it can help in the efforts to reduce this time lost to sickness and minimise the risk of infections spreading in your workplace. Not only that, but be part of strategy to help encourage staff to happily come back into the office!
Equally, because of the effective use of this technology and the benefits it can have; it’s also a great tool in reducing the fear factor amongst customers and acts as a tool in gravitating custom back to your business. This is especially pertinent for those businesses in hospitality who rely on the willingness of the general public to mix again.
UVC is also considered a green technology as it takes the reliance off the use of chemicals, bleach, water and throw-away sterilisation methods. As a result of this level of longevity, it’s rapid effectiveness and ability to operate as part of the infrastructure of a building, it takes time off manual cleaning efforts and acts a long-term, cost-effective disinfection solution. What is more, it is a very cost effective and time effective way to cleanse air compared to other methods such as opening the windows and having the heating turned up, as well as disinfection fogging.
How do I change from my existing service?
Ultimately you want a UVC solution that is fit for your environment to help ensure you are achieving the best cost-effective and germicidal irradiation outcomes. This comes off the back of government advice in the context of reducing bacteria and virus transmission within buildings. The government notes that UVC air cleaning devices can be an effective tool in improving air quality and reducing the risk of infections spreading through buildings.
To do this effectively, there are several key variables that need to be considered such as room size and levels of occupancy. We can work with you to provide expert recommendations on which UVC disinfection products are best suited for your sterilisation and hygiene needs. Our team of UVC disinfection technicians are certified in designing and installing UVC disinfection solutions through our partnership with Philips and Signify.
The maintenance on these products are very limited, because it’s the light which is the form of disinfection, not any filters. With your typical UVC bulb lasting for 9,000 hours, we recommend a maintenance review after at least 2 years. If you were to use a UVC product for 10 hours a day, 5 days a week, every day of the year that would equate to 2,600 hours. Based of this example, the UVC bulb would last at least 3 years.
UVC solutions can be easily fitted into any building, as well as be designed to fit into newly constructed builds as well. Equally, this technology is also available in the form of portable units of varying sizes, which can be particularly valuable for spaces which have variable levels of occupancy.
What UVC Disinfection product should I buy?
By understanding your hygiene objectives; we can work with you to guide you towards the best disinfection solution that is going to work best for your business. For instance, smaller meeting rooms would benefit from portable UVC air purifiers to use when the room is in use. Where as high traffic shared working areas could benefit from an installed upper-air UVC solution to help target areas of higher risks of transmission due to the concentration of people.
You might also be experiencing a transmission risk at shared touch points across your building such as hand-held devices and keyboards. Investing in object or surface UVC disinfection would then look to treat these surfaces and inactive any lasting pathogens.
Speak to one of our trained UVC technicians today to find out how this technology could work best for you and your business on enquiries@dakro.co.uk or 0121 5549 6134
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