Takeaways from the International Conference on UV Disinfection for Air and Surfaces

October 6, 2020

Germicidal ultraviolet irradiation is a proven methodology for inactivating viruses on solid surfaces, in water and in air. UV-C technology has found many valuable applications, for example in disinfecting hospital rooms, aircrafts, and drinking water. As such it is expected to be a useful tool in the fight against the COVID-19 pandemic. UV-C is a category of ultraviolet light with wavelengths between 100-280 nm and is the most effective UV light for disinfection

With the pandemic helping to intensify challenges in air and surface disinfection systems, the 2020 International Conference on UV Disinfection for Air and Surfaces (ICUDAS) was both timely and relevant. Industry leaders, scientist and physicians gathered and participated in the two-day event, which covered UV-C technology, standards, lights sources, and challenges.

This was the first ICUDAS hosted by the International UV Association (IUVA). The vision for this conference was to bring together industry leaders involved in all aspects of air and surface UV disinfection to spur communication and networking. The first day of the conference began with industry and regulatory perspectives followed by technical sessions addressing key validation aspects of optics, radiometry, and photobiology. The second day of the conference explored the current state of the art in UV-LEDS and FAR UV-C followed by wrap up sessions exploring commercial and consumer applications from healthcare acquired infections to the COVID-19 pandemic. Between session there were multiple roundtable breakout sessions to network, discuss, and debate.

My Key Takeaways from the Conference

There is a lack of standardization for testing air and surface systems.
The only rules today are the levels of exposure needed to achieve log3 or greater disinfection, but not how to prove it.  I liken this status to the time when high power LEDs and solid-state lighting was in its infancy in the early 2000s. Then the industry saw the potential for LEDs disrupting the lighting industry with energy efficient lighting. However, there was no uniformity in testing or reporting or even agreement on nomenclature to use to communicate. Because of this, consumers were seeing many false claims of performance, much like now with some UV disinfection devices with false claims to wipe out bacteria from air and surfaces. With time and with the leadership of industry groups like the Illuminating Engineering Society (IES) and testing procedures committee volunteers working with government bodies created measurement guides, standards, and regulations for the industry. Today consumers are ensured that the lighting products they purchase are ENERGY STAR® rated for energy efficient lighting and easy to understand lighting facts. It took more than a decade, but today it is the norm.  I envision a similar road ahead, but much quicker for UV-C air and surface disinfection regulation. Which leads me to my next take away.

What is being done for standardization?
Earlier this year the UVGA announced a Memorandum of Understanding (MOU) with the Illumination Engineers Society to assemble experts in the measurement of UV-C emissions to develop ANSI standards for measurements and characterization of UV-C devices. At this conference Alex Baker and Cameron Miller presented the challenges and the work being done towards this effort which includes four new methods for electrical and UV Measurement of low-pressure mercury sources, solid state sources, excimer sources/discharge sources and UVC disinfection products and another standard on Calibration and Characterization of UV-C detectors. Dr William Bahnfleth reported on an Epidemic and Germicidal UV task force he is chairing through the American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASRAE). The task force was formed in March 2020 and they are recommending UV-C only for air cleaning technologies supported by strong efficacy and safety. There is much work to be done, but we can expect to see the new standards for the measurement of UV light sources in the coming year followed by the UV detector standard.

UV Sources: go short or go deep?
There was much discussion on UV light sources. There were discussions on traditional mercury pressure lamps which have the advantages of high irradiance levels but can generate a lot of heat, have a relative short life, and off course the mercury disposal thing. Then there are UV-C LEDs which promise longer life based on LM-70 data, flexibility in directionality and design, and relatively lower heat generation, but are limited (for now) to relatively low irradiance levels good for closer proximity irradiation applications. These solid-state sources tend to be adopted into newer products being introduced in the UV-C air and surface disinfection systems. The other light source technology discussed was the FAR UV excimer sources which offer disinfection and safety at wavelength harmless to human skin when appropriately filtering out the harmful UV wavelengths. 

And finally, who or what will drive innovation?
UV-C for air and surface disinfection is not new to those in the industry, particularly in hospital settings where disinfection is critical. However, it took a pandemic for the masses to understand the potential of infections from surface and airborne viruses. History has shown with disruption comes innovation. Companies need to transition to grow. As Ginni Rometty, Executive Chairman of IBM said, “Growth and comfort do not coexist.” So, who is going to drive the demand and pay for the technology advancements?

Author Greg McKee is Chief Technologist and Product Market Manager for Labsphere. Greg served over 20 years on the IES Testing Procedures Committee and 9 years as an Executive Director on the Council for Optical Radiometric Measurements (CORM).