Source: Service Management
UV-C light, you read and hear more and more about it. We as Service Management messages about this with some regularity. But what is it really? What are its advantages and disadvantages? And will it replace traditional disinfection methods? We asked Mike van der Kamp, co-owner of UVSence, and Marcel van Duinen, founder of ClearSafeProducts.
UV-C is a form of ultraviolet radiation that severely damages the DNA and RNA of micro-organisms. This damage prevents the micro-organisms, such as bacteria, viruses and fungi, from dividing and causes them to die. “UV-C is in that sense a disinfectant just like chlorine,” says Van Duinen. “Chlorine inactivates bacteria and viruses and so does UV-C. And so are other disinfectants.”
When we enter somewhere and you smell a chlorine odour, we often think it is clean. But it doesn't have to be.
Knowledge on use of UV-C is lacking
Chlorine knows no secrets, but there is still a lot of confusion about UV-C. Van Duinen: “Every cleaner is used to working with wet disinfectants. This has been commonplace for decades. Everyone knows how to apply it. For the use of UV-C, that knowledge is as yet lacking. Yet it has been used for years, for example, for static solutions in the food industry. There, they have UV-C lines and tunnels through which packaging is passed and disinfected. The knowledge on how to disinfect offices with UV-C is often lacking, which is why it is not yet widely used.”
Van der Kamp adds: “Most cleaners need a 30-second soaking time to be effective. This is almost not achieved in practice. Whether or not because some substrates cannot handle this either. So there is almost never any real disinfection. Yet we often think when we enter somewhere and you smell a chlorine odour that it is clean. But it doesn't have to be that way.”
UV-C works much faster
“If you have a room to clean and you spray a little chlorine three times, nothing happens. Then you can say that chlorine disinfects 99.99 per cent, but only if you apply it properly. If you want to disinfect a door handle with a chlorine wipe, you need 30 seconds of contact time if you want to arrive at a log 4 reduction (99.99 per cent disinfection). You have to take that into account.”
“With a UV-C device, depending on the UV-C wattage, this works much faster. If you hold such a device within ten centimetres of a door handle, log 3 reduction (99.9 per cent disinfection) is a reality after two seconds. That's a big difference from chlorine, but you have to know how to apply it.”
Many devices fail
The effectiveness of UV-C has been proven for years, both gentlemen argue. So how come it is not yet commonplace in the cleaning industry? Van Duinen: “Many devices come on the market that contain UV-C, but that does not mean that such a device works well. If I market a cleaning product and I say it has chlorine in it, it doesn't mean it's a good product. There may be too little chlorine in it or the composition may be wrong. There's more to it and that includes UV-C. There is a big flaw there. A number of products currently on the market are, in our opinion, of insufficient quality to establish a good disinfection protocol. In addition, users are often not properly supervised when using UV-C.”
The greater the distance between the lamp and the surface, the longer the lamp should be on.
The distance of a UV-C lamp from a surface to be disinfected is close, Van Duinen stresses. “If you double the distance, the UV-C power, i.e. the disinfection power, decreases by a factor of four. The greater the distance between the lamp and the surface, the longer the lamp has to be on. This is not a problem if you have an hour. But it doesn't work if you have little time to disinfect between, say, two visits in a dental office. So if you use UV-C, you have to do it close to the surface. This knowledge is still insufficient in the market.”
Combine both worlds
According to Van der Kamp, the ideal disinfection protocol consists of a combination of traditional cleaning and the use of UV-C. “Cleaning is ultimately a cost item. It is therefore important as a cleaning company to take stock of where you can easily use UV-C and where the traditional method is better. It's a waste of money to bet only on UV-C because it's not always suitable. You have to find the balance in that, where disinfection is actually done. Then you end up creating a win-win situation. A cleaning company should actually advise a client how they can do it better. That it doesn't always work to run an extra wipe over something.”
What do cleaning, disinfection and coronavirus have to do with each other?
The real added value of UV-C over traditional disinfection comes around the corner for surfaces to be disinfected manually. Van Duinen: “The more complicated it is and the longer you spend disinfecting it, the more attractive UV-C becomes. You can save money and the result is better. In the food industry, if you want to disinfect a whole wall, you can go a long way with a good foam lance and UV-C is not cost-effective there. As soon as it comes to smaller, complicated forms, as you see a lot in offices, laboratories, hotel rooms and hospitals, the advantages of UV-C come around the corner. You know that in advance.”
Ecological disinfection with UV-C
According to Van de Kamp, UV-C is an environmentally friendly solution, compared to many disinfectants, because it does not involve chemicals. “Many disinfectants emit harmful gases and/or are downright harmful to the environment and the staff using them. You have to ask yourself whether the end justifies the means.”
“Moreover, it saves a lot of empty plastic bottles,” Van de Kamp continued. “It is also common for car dealers to detonate an ‘ozone bomb’ before delivering a car. The car is thus perfectly disinfected, but an ozone residue also remains somewhere and you, the user, get it. But it also happens in hotel rooms. We know that's harmful. And how desirable is it then?”
Look for critical spots
There is no single answer to these questions. Van Duinen: “Above all, look at it practically. Use UV-C where it is cost-effective and/or where current disinfection falls short. And look carefully at the most critical areas, where many different people have contact with the same surface. Fitting UV-C into an existing protocol is not that difficult. If you just take your time and review the current routine with practical knowledge about UV-C, you will soon save time and disinfection levels will be improved. And a final tip: critically review the technical specifications of UV-C devices you are offered, or get good advice.”
English (UK)