PUTTING UV DISINFECTION UNDER THE SPOTLIGHT
Nathan Delaney, Light Link Operations Director
Keeping staff and customers safe is the number one priority for businesses right now, and people are searching for effective ways to ensure wellbeing. Since COVID-19, there have been fundamental changes to office design that impact how we work and interact in the workplace, in particular for collaboration areas and communal spaces due to social distancing guidelines. One example of immediate change is the introduction of clear screens between desks.
A weapon we’re hearing a lot about in the lighting industry is ultraviolet light and its potential for killing coronavirus. In fact, this technology has been used to kill viruses in hospitals for many years, so UV as a disinfection tool is nothing new. But what has changed is how it’s being discussed as a mainstream option to keep workplaces clean, with a host of new products, making some pretty big claims, exploding onto the market.
Similar to UVA and UVB rays from the sun, UVC is incredibly potent, meaning the right training and product knowledge is vital. Yes, we should explore all options for safer spaces, but does the integration of UVC sterilising products into lighting solutions make sense? And should lighting companies with no specialist experience be selling products that are dangerous if not used correctly? We spoke to two of our partners to delve deeper into the topic.
What is UV light disinfection?
Ultraviolet radiation is a proven process – documented since the early days of research in biology and the physics of light waves – for disinfecting water, air, or solid surfaces that are microbiologically contaminated. UV light penetrates the cell wall of a microorganism and causes a reaction in its DNA, breaking it down, killing the cells, and preventing it from growing and multiplying.
How has it been used previously?
Most recently in a hospital setting for disinfecting operating rooms, as well as overnight cleaning in laboratories and meatpacking facilities. Before that, using UV light for disinfecting drinking water dates back to 1910 in Marseille, France. In 1955, UV water treatment systems were applied in Austria and Switzerland; by 1985 about 1,500 plants were employed in Europe. In 1998, it was found that protozoa, such as cryptosporidium and giardia were more vulnerable to UV light than previously thought, which paved the way for wide-scale use for water treatment in North America. By 2001, over 6,000 UV water treatment plants were operating in Europe.
People are very curious about UV light products, how they work, and their effectiveness, and we have definitely seen a growing appetite for them. Some examples of products for commercial disinfection purposes include germicidal UV light bulbs, UV sanitiser wands, portable UV sterilisers, and even UV disinfection robots. Educating clients on how they can be used to combat the spread of COVID-19 is very important as this could be one of the long-term preventive measures, making them a common addition to fit-outs. That said, they should always be sourced through the proper channels to ensure safety.
Risks and considerations
Although the FDA hasn’t received any problem reports associated with using UV light products, excessive exposure to UV light during cleaning may put a user at risk of eye injury, skin burns, or even an increased risk of skin cancer. Effectiveness is another issue. Clients need to understand that although the efficiency of UV Lights has been proven to kill certain pathogens, all UVC solutions need accurate deactivation (fluence) response curves to determine the UV exposure required for the desired level of disinfection. If this isn’t done properly, it won’t work.
Mark Cunningham, Trinity Lighting (makers of Air~Lume)
Regrettably, we’re seeing an influx of very dangerous UVC products, with virtually no safety or performance regulations. People are buying products at very high prices that aren’t capable of fulfilling the claims and put users at risk. The suggestion that one bare mercury lamp will disinfect a large space, for example, is not feasible and creates a false sense of security. If an area is shielded from the light, it’s not irradiated. Where residual bacteria and pathogens remain on surfaces, they will rapidly recolonise irradiated areas as there is no lasting residual effect once the light is removed. Similarly, with air disinfection, UVC irradiation can disinfect air that is within the UVC zone of contact but, once the light is off, any air entering the circulation area is not sterilised. As there can be no human occupation during irradiation, as soon as someone enters the space or opens the door, contaminated air can re-enter the atmosphere. This is why, when we developed Air~Lume two years ago, we focused on the safe integration of the UVC source and the ability for it to operate continuously in occupied spaces.
Is it a cure-all?
There needs to be a wider evaluation of office and commercial building air quality and general cleaning regimes because UVC, whilst very effective, is not a panacea. It can be considered an extremely useful tool in combination with a holistic approach. With regard to products such as robotic towers, we need to understood that these only irradiate surfaces in line of sight; if it’s not seen it’s not cleaned. Manual cleaning cannot be replaced by UVC, and is still essential. As in hospitals, manual deep cleaning remains the best method, supplemented in surgical areas with UVC. We should also recognise that in conventional premises, the surfaces and furnishings are not resilient enough against high-power UV irradiation and will get progressively damaged by photodegradation (as we see with the yellowing of surfaces by the sun), leading to hefty redecorating bills.
What to look for
The UVC market has been largely unregulated, as medical-grade products were governed by an industry code of ethics and liabilities. The explosion of interest in other areas has resulted in professional bodies, such as IES, CIE, and GLA, all issuing professional guidance and safety recommendations, and we expect a formal regulatory documentation to be ready within 12 months. In the interim, clients should seek genuine advice supported by scientific information. As always, if it sounds too good to be true, it probably is. UVC is not a quick fix, it is a very powerful tool to be used with the appropriate application and consumption. For mainstream surface disinfection, the risks still outweigh the benefits.